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CALAMOS CONVERTIBLE OPPORTUNITIES & INCOME FUND

Regulatory Filings Jun 24, 2011

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N-CSRS 1 c63809nvcsrs.htm FORM N-CSRS nvcsrs PAGEBREAK

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT INVESTMENT COMPANIES

INVESTMENT COMPANY ACT FILE NUMBER: 811-21080

EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER: Calamos Convertible Opportunities and Income Fund

ADDRESS OF PRINCIPAL EXECUTIVE OFFICES: 2020 Calamos Court, Naperville,
Illinois 60563-2787
NAME AND ADDRESS OF AGENT FOR SERVICE: John P. Calamos, Sr., President,
Calamos Advisors LLC
2020 Calamos Court
Naperville, Illinois
60563-2787

REGISTRANT’S TELEPHONE NUMBER, INCLUDING AREA CODE: (630) 245-7200

DATE OF FISCAL YEAR END: October 31, 2011

DATE OF REPORTING PERIOD: November 1, 2010 through April 30, 2011

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ITEM 1. REPORTS TO SHAREHOLDERS

Include a copy of the report transmitted to stockholders pursuant to Rule 30e-1 under the Act (17 CFR 270. 30e-1).

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Letter to Shareholders

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Letter to Shareholders

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we were able to achieve a higher return than our borrowing costs. We intend to continue to utilize leverage judiciously, as long as we believe it will serve the fund’s shareholders well.

As part of our emphasis on risk management, we employed interest rate swaps as a hedge against a potential rise in interest rates. We use these swaps to manage the borrowing costs associated with our leverage activities. Through these swaps, we essentially lock down an interest rate that we believe to be attractive. Currently, interest rates are at historically low levels throughout much of the fixed income market. However, given the current economic landscape, we believe that it is possible that rates could surge very quickly, even over a period of weeks, as was the case in the 1970s and 1980s. We believe the fund’s interest rate swaps could be a valuable tool to help protect the fund from increasing borrowing costs, should rates rise.

The Market and Economic Environment: Resilience Amid Volatility

During the reporting period, the global markets were unsettled by unexpected events. These included the earthquake and tsunami in Japan, as well as political turmoil and violence in the Middle East and North Africa. Other longer-running considerations persisted, such as the debt burdens of developed nations, commodity prices, inflationary pressures, and evolving geopolitical relationships between established and rising powers.

While volatility spikes persisted, investors seemed to focus on more positive influences. There were also continued signs of improving economic conditions within the United States. For example, we saw many instances of improving corporate profits and balance sheets, as well as gains in private sector job growth. Credit markets remained open and strong, providing good access to capital for large cap and mid cap companies, in particular.

In this environment, the U.S. convertible and high yield markets demonstrated resilience. For the six-month period ending April 30, 2011, convertible securities gained 11.69%, as measured by the BofA Merrill Lynch U.S. All Convertible Ex-Mandatory Index. High yield securities earned 6.01%, as measured by the Credit Suisse High Yield Index. Within both the convertible and high yield marketplace, the most speculative tiers led, as investors sought yield. However, as investors became increasingly attentive to the potential long-term implications of government debt and dollar devaluation, the broad bond market lagged, with the Barclays Capital U.S. Government/Credit Index returning -0.61%.

Given the prevailing low interest rate environment and investors’ determined quest for yield, high yield issuance remained robust, driven in large measure by debt refinancing activity. Defaults remained low against a backdrop of improving capital market conditions and abundant liquidity. Convertible securities issuance lagged, as companies favored issuing non-convertible debt in a low-rate environment.

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Letter to Shareholders

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Opportunities Across Asset Classes

As we will discuss in the Q&A section, our team continues to find high yield corporate bonds and convertible securities that we believe meet our criteria. We have sought credits that offer attractive yields, as well as reliable debt servicing prospects and the opportunity for credit upgrades. Because we consider income within the context of total return, our approach to the most speculative credits remains particularly selective.

Where possible, we are maintaining a focus on U.S. businesses with global footprints, global management and global revenue streams. We have sought to position the fund to benefit from global secular trends, such as the growth of a middle class in emerging markets, corporations’ focus on productivity enhancements and consumers’ continued appetite for technology innovations. In a global economy, these are trends that U.S. companies can participate in.

In Closing

We believe that innovation thrives in all market environments. Our investment team continues to find many businesses that are guided by a spirit of creativity and entrepreneurship—companies that we have seen adapt and change as the global economy evolves.

While I believe that globalization presents a very exciting backdrop for U.S. companies and investors, the opportunity potential does vary considerably from company to company and industry to industry. Because of this, we believe that an active investment approach is particularly important. We believe our decades of experience, our selective, risk-aware approach and our unwavering commitment to our shareholders will continue to differentiate CHI as an enhanced fixed income offering.

If you would like additional information about this fund or our other closed-end offerings, please contact your financial advisor or our client services team at 800.582.6959 (Monday through Friday from 8:00 a.m. to 6:00 p.m., Central Time). We also invite you to visit us at www.calamos.com.

We thank you for your continued trust. It is an honor to partner with you to help you achieve your financial goals.

Sincerely,

John P. Calamos, Sr. CEO and Co-CIO Calamos Advisors LLC

This report is for informational purposes only and should not be considered investment advice.

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CALAMOS CONVERTIBLE OPPORTUNITIES AND INCOME FUND SEMIANNUAL REPORT 3

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The Calamos Closed-End Funds: An Overview

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In our closed-end funds, we draw upon decades of investment experience, including a long history of opportunistically blending asset classes in an attempt to capture upside potential while managing downside risk. We launched our first closed-end fund in 2002.

Closed-end funds are long-term investments. Most focus on providing monthly distributions, but there are important differences among individual closed-end funds. Calamos closed-end funds can be grouped into two broad categories: (1) enhanced fixed income and (2) total return. Funds in both groups provide a monthly distribution stream and invest in a combination of asset classes.

| OBJECTIVE: ENHANCED FIXED
INCOME | OBJECTIVE: TOTAL
RETURN |
| --- | --- |
| Portfolios Positioned to Pursue High Current Income from
Income and Capital Gains | Portfolios Positioned to Seek Current Income, with Increased
Emphasis on Capital Gains Potential |
| Calamos Convertible Opportunities and Income Fund (Ticker:
CHI) | Calamos Global Total Return Fund (Ticker: CGO) |
| Invests in high-yield and convertible securities, primarily in
U.S. markets | Invests in equities and higher-yielding convertible securities
and corporate bonds, in both U.S. and non-U.S. markets |
| Calamos Convertible and High Income Fund (Ticker CHY) | Calamos Strategic Total Return Fund (Ticker: CSQ) |
| Invests in high-yield and convertible securities, primarily in
U.S. markets | Invests in equities and higher-yielding convertible securities
and corporate bonds, primarily in U.S. markets |
| Calamos Global Dynamic Income Fund (Ticker: CHW) | |
| Invests in global fixed-income securities, alternative
investments and equities | |

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Our Level Rate Distribution Policy

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Investors often choose a closed-end fund because they seek a steady stream of income. In recognition of this, all five Calamos closed-end funds have adopted a level distribution policy. Our policy is to pay a distribution reflective of the funds’ past results and projected earnings potential through income as well as capital gains. Our team is focused on delivering an attractive monthly distribution, while maintaining a long-term focus on risk management. The level of the funds’ distributions can be greatly influenced by market conditions, including the interest rate environment. The funds’ distributions will depend on the individual performance of positions the funds hold, our view of the benefits of retaining leverage, fund tax considerations, and maintaining regulatory requirements.

For more information about any of these funds, we encourage you to contact your financial advisor or Calamos Investments at 800.582.6959 (Monday through Friday from 8:00 a.m. to 6:00 p.m., Central Time). You can also visit us at www.calamos.com.

For more information on our level rate distribution policy, please see page 33.

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Investment Team Discussion

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Investment Team Discussion

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As of the end of the reporting period, the fund’s shares traded at a 2.50% premium to net asset value, a slight increase from the start of the reporting period, when the premium was 1.95%. We believe that this indicates favorable recognition of the fund’s income stream and long-term record within the marketplace.

Q. How do NAV and market price return differ?

A. Closed-end funds trade on exchanges, where the price of shares may be driven by factors other than the value of the underlying securities. The price of a share in the market is called market value. Market price may be influenced by factors unrelated to the performance of the fund’s holdings.

A fund’s NAV return measures the return of the individual securities in the portfolio, less fund expenses. It also measures how a manager was able to capitalize on market opportunities. Because we believe closed-end funds are best utilized as a long-term holding within asset allocations, we believe that NAV return is the better measure of a fund’s performance.

Q. Please discuss the fund’s distributions during the annual period.

A. As we discussed in the opening letter, we employ a level rate distribution policy within this fund with the goal of providing shareholders with a consistent distribution stream. The fund provided a steady distribution stream over the period. Monthly distributions were $0.0950 per share. The fund’s annual distribution rate was 8.41% of market price as of April 30, 2011.

We believe that both the fund’s distribution rate and level remained attractive and competitive, as low interest rates limited yield opportunities in much of the marketplace. For example, as of April 30, 2011, the dividend yield of S&P 500 Index stocks averaged 1.8%. Yields also remained low within the U.S. government bond market, with 10-Year Treasurys and 30-Year Treasurys yielding 3.5% and 4.5%, respectively. Moreover, we believe the fund’s distribution rate is particularly compelling in that the fund also captured much of the equity market’s return, demonstrating the potential merits of a total return approach.

Q. What factors influenced performance over the reporting period?

A. Both the fund’s convertible securities stake and high yield corporate bond holdings contributed positively to performance. To some extent, the fund’s performance was moderated by our emphasis on quality as well as income. Broadly speaking, many of the most speculative grade issues in the convertible securities market were particularly well rewarded by investors in their hunt for yield. However, because we take a total return approach that focuses on avoiding downside risk, we took a very selective approach to lower rated issues, particularly those rated CCC.

From a sector perspective, security selection within the financials sector benefited performance relative to the Credit Suisse High Yield Index. The fund’s holdings in the asset management industry performed particularly well. Within financials, we are favoring areas such as asset management over areas such as banks, which we believe may struggle due to increasing regulatory requirements. The fund’s performance was further enhanced by security selection within the energy sector. Here, holdings in the oil-and-gas exploration-and-production industry contributed notably. In our positioning decisions in the energy sector, we have sought to balance return considerations with a thorough assessment of potential risks, such as increased regulatory risks and volatility associated with commodity prices.

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Our use of leverage was also beneficial to the fund’s performance. We were able to borrow at low rates and then invest the proceeds in securities that generated higher returns. As we discussed in the opening letter, we utilized interest rate swaps to lock in an interest rate we believe to be attractive and to provide a hedge against a potential rise in interest rates.

Q. How is the fund positioned?

A. We have found securities across asset classes that we believe are appropriate for the fund’s enhanced fixed income approach. As of April 30, 2011, the fund’s largest allocation, based on total investments, was to corporate bonds, followed by convertible securities. As of the close of the reporting period, the majority of securities were rated BB, which is one of the higher tiers of the high yield universe. We also found opportunities in investment grade credits (those rated BBB and above); these totaled about 27% of portfolio holdings (excluding equities) as of the end of the reporting period. This reflects our view that while economic recovery is underway, there still may be challenges to growth. In this environment, we believe that companies with better financial health and more reliable debt servicing are the appropriate choices on the whole. Where possible, we have favored larger U.S.-based global businesses with diversified revenues and strong brands. We believe that these companies may be particularly well positioned to capitalize on the growth trends we see around the world, including those related to emerging markets.

Q. What is your outlook for Calamos Convertible Opportunities and Income Fund?

A. We believe that the markets provide ample opportunities for this fund’s enhanced fixed income approach, and we maintain high conviction in its strategy. In our view, the fund’s use of convertible securities and high yield corporate bonds remains an attractive choice, both in the current low rate environment as well as in an environment where rates could rise, perhaps quite suddenly. Because of this approach, this fund may be less susceptible to interest rate changes that could result from dollar devaluation or debt burdens, compared to those closed-end funds that rely primarily on U.S. Treasury bonds or municipal securities for yield.

In our view, active, multi-faceted risk management will remain very important. As we noted, although recovery appears to be underway in the U.S., we do not believe that the current environment is one in which “a rising tide will lift all boats.” We do expect continued spikes in volatility and, in this environment, we believe that our ability to utilize a broad range of securities will remain an important differentiator of our enhanced fixed income approach.

Our conviction in the portfolio is furthered by our view of the growth potential we see in the global economy and the different ways innovative companies are participating in these opportunities. We believe that our preference for U.S.-based companies with global strategies and global reach will allow this fund to participate in the exciting long-term trends we see in many parts of the global economy, and will support its pursuit of a high stream of income and steady distributions with a secondary focus on capital gains.

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Schedule of Investments April 30, 2011 (Unaudited)

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PRINCIPAL — AMOUNT VALUE
CORPORATE BONDS (70.9%)
Consumer Discretionary (12.6%)
1,917,000 American Axle & Manufacturing, Inc. 7.875%, 03/01/17 $ 1,979,303
3,286,000 Asbury Automotive Group, Inc.µ 7.625%, 03/15/17 3,376,365
5,737,000 Cooper Tire & Rubber Companyµ 8.000%, 12/15/19 6,160,104
1,729,000 Dana Holding Corp. 6.750%, 02/15/21 1,752,774
DISH Network Corp.µ
5,915,000 7.875%, 09/01/19 6,432,562
4,952,000 7.125%, 02/01/16 5,298,640
5,633,000 Exide Technologiesµ* 8.625%, 02/01/18 6,069,557
2,347,000 Express, LLC 8.750%, 03/01/18 2,578,766
1,106,000 GameStop Corp. 8.000%, 10/01/12 1,130,885
Goodyear Tire & Rubber Company
4,694,000 8.250%, 08/15/20 5,239,677
808,000 7.000%, 03/15/28µ 779,720
5,398,000 Hanesbrands, Inc.µ‡ 3.831%, 12/15/14 5,424,990
3,755,000 Hasbro, Inc.µ 6.600%, 07/15/28 3,979,650
1,061,000 Interpublic Group of Companies, Inc.µ 10.000%, 07/15/17 1,270,548
J.C. Penney Company, Inc.
2,924,000 6.375%, 10/15/36 2,646,220
2,694,000 7.125%, 11/15/23 2,788,290
5,502,000 Jarden Corp.µ 7.500%, 05/01/17 5,935,282
2,816,000 Liberty Media Corp.µ 8.250%, 02/01/30 2,745,600
Limited Brands, Inc.
2,816,000 7.600%, 07/15/37 2,794,880
1,453,000 6.625%, 04/01/21 1,511,120
737,000 6.950%, 03/01/33 687,253
2,816,000 Live Nation Entertainment, Inc.* 8.125%, 05/15/18 2,886,400
4,225,000 Macy’s Retail Holdings, Inc.µ 5.900%, 12/01/16 4,589,406
4,009,000 NetFlix, Inc.µ 8.500%, 11/15/17 4,550,215
Royal Caribbean Cruises, Ltd.
4,694,000 7.500%, 10/15/27 4,705,735
1,878,000 7.250%, 06/15/16µ 2,014,155
939,000 7.000%, 06/15/13µ 1,015,294
Service Corp. International
6,572,000 7.500%, 04/01/27µ 6,415,915
939,000 7.625%, 10/01/18µ 1,056,375
939,000 7.000%,
05/15/19 ~ 1,002,383
1,408,000 Speedway Motorsports, Inc. 8.750%, 06/01/16 1,548,800
3,228,000 Vail Resorts, Inc.* 6.500%, 05/01/19 3,308,700
4,065,000 Wynn Las Vegas, LLCµ 7.750%, 08/15/20 4,461,338
108,136,902
Consumer Staples (2.1%)
3,286,000 Chiquita Brands International, Inc.µ 8.875%, 12/01/15 3,401,010
Constellation Brands, Inc.
1,878,000 7.250%, 09/01/16µ 2,056,410
704,000 8.375%, 12/15/14 804,320
2,652,000 Darling International, Inc.µ* 8.500%, 12/15/18 2,903,940
116,000 Elizabeth Arden, Inc. 7.375%, 03/15/21 122,670
870,000 Kraton Polymers LLC* 6.750%, 03/01/19 889,575
3,828,000 Perry Ellis International, Inc. 7.875%, 04/01/19 4,009,830
3,223,000 Reynolds American, Inc.µ 7.250%, 06/15/37 3,522,420
17,710,175
Energy (15.1%)
Arch Coal, Inc.
5,361,000 7.250%, 10/01/20 5,809,984
704,000 8.750%, 08/01/16 792,000
3,091,000 Arch Western Finance, LLC 6.750%, 07/01/13 3,125,774
Basic Energy Services, Inc.
6,357,000 7.750%, 02/15/19* 6,690,742
1,573,000 7.125%, 04/15/16 1,614,291
Berry Petroleum Company
4,957,000 8.250%, 11/01/16 5,266,813
1,878,000 10.250%, 06/01/14 2,192,565
2,054,000 Boart Longyear Management Pty., Ltd.* 7.000%, 04/01/21 2,136,160
3,755,000 Brigham Exploration Company 8.750%, 10/01/18 4,205,600
7,698,000 Bristow Group, Inc.µ 7.500%, 09/15/17 8,159,880
7,041,000 Calfrac Holdings, LP* 7.500%, 12/01/20 7,393,050
6,501,000 Carrizo Oil & Gas, Inc.* 8.625%, 10/15/18 6,972,322
782,000 Clayton Williams Energy, Inc.* 7.750%, 04/01/19 785,910
3,755,000 Complete Production Services, Inc.µ 8.000%, 12/15/16 3,980,300
5,915,000 Comstock Resources, Inc.µ 8.375%, 10/15/17 6,269,900

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
4,544,000 Concho Resources, Inc.µ 8.625%, 10/01/17 $ 5,043,840
4,694,000 EXCO Resources, Inc.µ 7.500%, 09/15/18 4,782,013
Frontier Oil Corp.
5,708,000 8.500%, 09/15/16µ 6,221,720
765,000 6.875%, 11/15/18 803,250
2,910,000 GulfMark Offshore, Inc.µ 7.750%, 07/15/14 2,982,750
5,257,000 Helix Energy Solutions Group, Inc.µ* 9.500%, 01/15/16 5,598,705
1,906,000 Holly Corp.µ 9.875%, 06/15/17 2,158,545
2,751,000 Hornbeck Offshore Services, Inc.µ 8.000%, 09/01/17 2,854,163
3,755,000 Pride International, Inc.µ 8.500%, 06/15/19 4,724,128
3,755,000 SEACOR Holdings, Inc. 7.375%, 10/01/19 4,064,712
6,102,000 SESI, LLCµ 6.875%, 06/01/14 6,262,177
3,583,000 SM Energy Company* 6.625%, 02/15/19 3,708,405
Swift Energy Companyµ
5,070,000 8.875%, 01/15/20 5,577,000
2,347,000 7.125%, 06/01/17 2,417,410
4,225,000 Trinidad Drilling, Ltd.µ* 7.875%, 01/15/19 4,499,625
2,236,000 Whiting Petroleum Corp.µ 6.500%, 10/01/18 2,347,800
129,441,534
Financials (2.7%)
2,254,000 AON Corp. 8.205%, 01/01/27 2,558,531
1,972,000 Janus Capital Group, Inc.µ 6.700%, 06/15/17 2,161,805
Leucadia National Corp.µ
7,276,000 8.125%, 09/15/15 8,112,740
1,156,000 7.125%, 03/15/17 1,219,580
4,225,000 Nuveen Investments, Inc. 10.500%, 11/15/15 4,420,406
OMEGA Healthcare Investors, Inc.
2,957,000 7.500%, 02/15/20µ 3,171,382
1,878,000 6.750%, 10/15/22* 1,917,908
23,562,352
Health Care (7.3%)
1,878,000 Bio-Rad Laboratories, Inc. 8.000%, 09/15/16 2,098,665
1,878,000 Community Health Systems, Inc. 8.875%, 07/15/15 1,924,950
5,105,000 DaVita, Inc.µ 6.625%, 11/01/20 5,264,531
7,041,000 Endo Pharmaceuticals Holdings, Inc.µ* 7.000%, 12/15/20 7,252,230
7,041,000 Giant Funding Corp.µ* 8.250%, 02/01/18 7,340,243
2,816,000 HCA, Inc.* 7.750%, 05/15/21 2,956,800
HealthSouth Corp.µ
2,582,000 7.750%, 09/15/22 2,753,058
2,065,000 7.250%, 10/01/18 2,188,900
Mylan, Inc.*
4,056,000 7.625%, 07/15/17 4,461,600
3,051,000 7.875%, 07/15/20 3,386,610
4,225,000 Talecris Biotherapeutics Holdings Corp.µ 7.750%, 11/15/16 4,668,625
Valeant Pharmaceuticals International, Inc.*
5,821,000 7.000%, 10/01/20 5,748,237
3,286,000 7.250%, 07/15/22 3,249,033
986,000 6.750%, 10/01/17 986,000
8,321,000 Warner Chilcott Company, LLC* 7.750%, 09/15/18 8,809,859
63,089,341
Industrials (10.9%)
2,816,000 Abengoa Finance SAU* 8.875%, 11/01/17 2,872,320
BE Aerospace, Inc.
4,225,000 8.500%, 07/01/18µ 4,721,437
316,000 6.875%, 10/01/20 334,170
Belden, Inc.
3,990,000 7.000%, 03/15/17µ 4,139,625
939,000 9.250%, 06/15/19 1,054,028
2,394,000 Clean Harbors, Inc.* 7.625%, 08/15/16 2,573,550
Deluxe Corp.µ
5,164,000 7.000%, 03/15/19* 5,228,550
4,361,000 7.375%, 06/01/15 4,540,891
3,887,000 Dycom Investments, Inc.* 7.125%, 01/15/21 4,037,621
2,216,000 Esterline Technologies Corp.µ 7.000%, 08/01/20 2,376,660
2,112,000 FTI Consulting, Inc.* 6.750%, 10/01/20 2,164,800
2,816,000 Gardner Denver, Inc. 8.000%, 05/01/13 2,826,560
GEO Group, Inc.
2,347,000 6.625%, 02/15/21* 2,352,867
704,000 7.750%, 10/15/17 756,800
3,715,000 GeoEye, Inc.µ 8.625%, 10/01/16 3,956,475
4,225,000 Great Lakes Dredge & Dock Corp.µ* 7.375%, 02/01/19 4,341,187

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
1,502,000 H&E Equipment Services, Inc.µ 8.375%, 07/15/16 $ 1,567,713
Huntington Ingalls Industries, Inc.*
235,000 6.875%, 03/15/18 248,513
224,000 7.125%, 03/15/21 236,880
4,050,000 Interline Brands, Inc.µ 7.000%, 11/15/18 4,191,750
1,878,000 Manitowoc Company, Inc. 8.500%, 11/01/20 2,065,800
Oshkosh Corp.
2,816,000 8.500%, 03/01/20 3,153,920
1,878,000 8.250%, 03/01/17 2,082,232
7,276,000 Spirit AeroSystems Holdings, Inc.µ 7.500%, 10/01/17 7,930,840
2,291,000 SPX Corp.µ 7.625%, 12/15/14 2,545,874
7,041,000 Terex Corp. 8.000%, 11/15/17 7,481,062
Triumph Group, Inc.
2,347,000 8.625%, 07/15/18µ 2,608,104
1,925,000 8.000%,
11/15/17 ~ 2,064,563
6,102,000 Tutor Perini Corp.µ* 7.625%, 11/01/18 6,254,550
3,262,000 WESCO Distribution, Inc.µ 7.500%, 10/15/17 3,384,325
94,093,667
Information Technology (8.7%)
Advanced Micro Devices, Inc.µ
5,633,000 7.750%, 08/01/20 5,900,568
4,572,000 8.125%, 12/15/17 4,857,750
Amkor Technology, Inc.
7,041,000 9.250%, 06/01/16µ 7,428,255
2,816,000 7.375%, 05/01/18 2,970,880
1,314,000 Anixter International, Inc.µ 5.950%, 03/01/15 1,330,425
2,910,000 Equinix, Inc.µ 8.125%, 03/01/18 3,164,625
469,000 Fidelity National Information Services, Inc. 7.875%, 07/15/20 520,590
188,000 Hynix Semiconductor, Inc.* 7.875%, 06/27/17 199,994
7,511,000 iGATE Corp.* 9.000%, 05/01/16 7,736,330
Jabil Circuit, Inc.µ
5,164,000 8.250%, 03/15/18 5,951,510
939,000 7.750%, 07/15/16 1,070,460
3,408,000 Lender Processing Services, Inc.µ 8.125%, 07/01/16 3,527,280
2,347,000 Lexmark International, Inc.µ 6.650%, 06/01/18 2,550,579
6,294,000 MEMC Electronic Materials, Inc.* 7.750%, 04/01/19 6,569,362
5,164,000 Sanmina-SCI Corp.*† 7.000%, 05/15/19 5,144,635
3,286,000 Seagate Technology* 6.875%, 05/01/20 3,351,720
3,051,000 ViaSat, Inc. 8.875%, 09/15/16 3,298,894
8,919,000 Xerox Corp. 8.000%, 02/01/27 9,070,338
74,644,195
Materials (6.3%)
2,582,000 Allegheny Ludlum Corp. 6.950%, 12/15/25 2,811,679
817,000 Ashland, Inc. 9.125%, 06/01/17 948,741
1,408,000 Ball Corp. 7.375%, 09/01/19 1,532,960
1,682,000 Boise Cascade Holdings, LLC 7.125%, 10/15/14 1,686,205
4,569,000 Clearwater Paper Corp.* 7.125%, 11/01/18 4,774,605
6,018,000 Greif, Inc.µ 7.750%, 08/01/19 6,634,845
2,601,000 Nalco Holding Company 8.250%, 05/15/17 2,844,844
2,661,000 Neenah Paper, Inc. 7.375%, 11/15/14 2,714,220
7,511,000 Sealed Air Corp.µ* 6.875%, 07/15/33 7,578,336
3,436,000 Silgan Holdings, Inc.µ 7.250%, 08/15/16 3,715,175
Steel Dynamics, Inc.
7,548,000 7.750%, 04/15/16µ 8,114,100
939,000 7.625%, 03/15/20 1,032,900
2,347,000 Texas Industries, Inc. 9.250%, 08/15/20 2,540,628
Union Carbide Corp.µ
3,755,000 7.500%, 06/01/25 4,181,666
2,910,000 7.875%, 04/01/23 3,336,635
54,447,539
Telecommunication Services (4.4%)
4,422,000 CenturyLink, Inc.µ 6.875%, 01/15/28 4,264,754
Frontier Communications Corp.
5,727,000 9.000%, 08/15/31µ 5,927,445
2,347,000 8.250%, 04/15/17 2,555,296
7,002,000 MetroPCS Wireless, Inc.µ 7.875%, 09/01/18 7,579,665
5,633,000 Qwest Communications International, Inc.µ 7.750%, 02/15/31 6,041,392
Windstream Corp.
6,384,000 7.750%, 10/15/20µ 6,798,960
1,878,000 7.750%, 10/15/20µ* 2,000,070

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
2,816,000 7.500%, 04/01/23* $ 2,872,320
38,039,902
Utilities (0.8%)
Calpine Corp.*
3,521,000 7.875%, 07/31/20 3,811,482
3,051,000 7.500%, 02/15/21 3,241,688
7,053,170
TOTAL CORPORATE BONDS (Cost $579,506,097) 610,218,777
CONVERTIBLE BONDS (24.0%)
Consumer Discretionary (3.4%)
Interpublic Group of Companies, Inc.µ
4,490,000 4.750%, 03/15/23 5,539,537
2,500,000 4.250%, 03/15/23 2,825,000
10,000,000 Liberty Media Corp. (Time Warner, Inc.)µ§ 3.125%, 03/30/23 12,300,000
10,620,000 Liberty Media Corp. (Viacom, CBS Corp. - Class B)µ§ 3.250%, 03/15/31 8,973,900
29,638,437
Energy (2.0%)
Chesapeake Energy Corp.
8,500,000 2.250%, 12/15/38 7,990,000
5,000,000 2.750%, 11/15/35µ 5,850,000
2,000,000 SM Energy Companyµ 3.500%, 04/01/27 2,900,000
16,740,000
Financials (0.8%)
3,000,000 Affiliated Managers Group, Inc.µ 3.950%, 08/15/38 3,491,250
2,850,000 Health Care REIT, Inc.µ 3.000%, 12/01/29 3,238,313
6,729,563
Health Care (3.4%)
16,000,000 Life Technologies Corp.µ 3.250%, 06/15/25 18,240,000
7,250,000 LifePoint Hospitals, Inc.µ 3.500%, 05/15/14 7,848,125
3,000,000 Salix Pharmaceuticals, Ltd.µ 2.750%, 05/15/15 3,442,500
29,530,625
Industrials (1.6%)
2,150,000 Alliant Techsystems, Inc. 3.000%, 08/15/24 2,405,312
10,500,000 Trinity Industries, Inc.µ 3.875%, 06/01/36 11,536,875
13,942,187
Information Technology (9.0%)
1,450,000 GBP Autonomy Corp., PLC 3.250%, 03/04/15 2,740,513
3,000,000 Blackboard, Inc.µ 3.250%, 07/01/27 3,030,000
5,500,000 Euronet Worldwide, Inc.µ 3.500%, 10/15/25 5,520,625
500,000 Hynix Semiconductor, Inc. 2.650%, 05/14/15 612,590
Intel Corp.µ
23,250,000 2.950%, 12/15/35 24,906,562
3,500,000 3.250%, 08/01/39 4,471,250
18,800,000 Linear Technology Corp.µ 3.000%, 05/01/27 20,421,500
4,000,000 ON Semiconductor Corp.µ 2.625%, 12/15/26 4,930,000
1,974,000 Rovi Corp. 2.625%, 02/15/40 2,435,423
6,250,000 Xilinx, Inc.* 2.625%, 06/15/17 8,132,813
77,201,276
Materials (3.8%)
4,300,000 Anglo American, PLC 4.000%, 05/07/14 8,480,261
6,100,000 AngloGold Ashanti, Ltd. 3.500%, 05/22/14 7,693,619
8,010,000 Newmont Mining Corp. 3.000%, 02/15/12 10,503,113
2,000,000 Sino-Forest Corp.* 5.000%, 08/01/13 2,722,500
2,620,000 Steel Dynamics, Inc.µ 5.125%, 06/15/14 3,294,650
32,694,143
TOTAL CONVERTIBLE BONDS (Cost $186,688,097) 206,476,231
U.S. GOVERNMENT AND AGENCY SECURITIES (0.6%)
United States Treasury
Note ~
3,286,000 1.000%, 03/31/12 3,309,123
1,690,000 0.875%, 01/31/12 1,698,913
TOTAL U.S. GOVERNMENT AND AGENCY SECURITIES (Cost $5,006,633) 5,008,036
SOVEREIGN BONDS (1.4%)
Federal Republic of Brazil
1,343,000 BRL 10.000%, 01/01/12 8,677,528
563,000 BRL 10.000%, 01/01/13 3,553,281
TOTAL SOVEREIGN BONDS (Cost $11,124,441) 12,230,809

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
SYNTHETIC CONVERTIBLE SECURITIES (5.6%)
Corporate Bonds (4.6%)
Consumer Discretionary (0.8%)
125,000 American Axle & Manufacturing, Inc. 7.875%, 03/01/17 $ 129,063
214,000 Asbury Automotive Group, Inc.µ 7.625%, 03/15/17 219,885
374,000 Cooper Tire & Rubber Companyµ 8.000%, 12/15/19 401,582
113,000 Dana Holding Corp. 6.750%, 02/15/21 114,554
DISH Network Corp.µ
385,000 7.875%, 09/01/19 418,687
323,000 7.125%, 02/01/16 345,610
367,000 Exide Technologiesµ* 8.625%, 02/01/18 395,442
153,000 Express, LLC 8.750%, 03/01/18 168,109
72,000 GameStop Corp. 8.000%, 10/01/12 73,620
Goodyear Tire & Rubber Company
306,000 8.250%, 08/15/20 341,572
53,000 7.000%, 03/15/28µ 51,145
352,000 Hanesbrands, Inc.µ‡ 3.831%, 12/15/14 353,760
245,000 Hasbro, Inc.µ 6.600%, 07/15/28 259,658
69,000 Interpublic Group of Companies, Inc.µ 10.000%, 07/15/17 82,628
J.C. Penney Company, Inc.
190,000 6.375%, 10/15/36 171,950
175,000 7.125%, 11/15/23 181,125
358,000 Jarden Corp.µ 7.500%, 05/01/17 386,192
184,000 Liberty Media Corp.µ 8.250%, 02/01/30 179,400
Limited Brands, Inc.
184,000 7.600%, 07/15/37 182,620
95,000 6.625%, 04/01/21 98,800
48,000 6.950%, 03/01/33 44,760
184,000 Live Nation Entertainment, Inc.* 8.125%, 05/15/18 188,600
275,000 Macy’s Retail Holdings, Inc.µ 5.900%, 12/01/16 298,719
261,000 NetFlix, Inc.µ 8.500%, 11/15/17 296,235
Royal Caribbean Cruises, Ltd.
306,000 7.500%, 10/15/27 306,765
122,000 7.250%, 06/15/16µ 130,845
61,000 7.000%, 06/15/13µ 65,956
Service Corp. International
428,000 7.500%, 04/01/27µ 417,835
61,000 7.625%, 10/01/18µ 68,625
61,000 7.000%,
05/15/19 ~ 65,118
92,000 Speedway Motorsports, Inc. 8.750%, 06/01/16 101,200
210,000 Vail Resorts, Inc.* 6.500%, 05/01/19 215,250
265,000 Wynn Las Vegas, LLCµ 7.750%, 08/15/20 290,838
7,046,148
Consumer Staples (0.1%)
214,000 Chiquita Brands International, Inc.µ 8.875%, 12/01/15 221,490
Constellation Brands, Inc.
122,000 7.250%, 09/01/16µ 133,590
46,000 8.375%, 12/15/14 52,555
173,000 Darling International, Inc.µ* 8.500%, 12/15/18 189,435
8,000 Elizabeth Arden, Inc. 7.375%, 03/15/21 8,460
57,000 Kraton Polymers LLC* 6.750%, 03/01/19 58,283
249,000 Perry Ellis International, Inc. 7.875%, 04/01/19 260,827
210,000 Reynolds American, Inc.µ 7.250%, 06/15/37 229,509
1,154,149
Energy (1.0%)
Arch Coal, Inc.
349,000 7.250%, 10/01/20 378,229
46,000 8.750%, 08/01/16 51,750
201,000 Arch Western Finance, LLC 6.750%, 07/01/13 203,261
Basic Energy Services, Inc.
414,000 7.750%, 02/15/19* 435,735
102,000 7.125%, 04/15/16 104,678
Berry Petroleum Company
323,000 8.250%, 11/01/16 343,187
122,000 10.250%, 06/01/14 142,435
134,000 Boart Longyear Management Pty., Ltd.* 7.000%, 04/01/21 139,360
245,000 Brigham Exploration Company 8.750%, 10/01/18 274,400
502,000 Bristow Group, Inc.µ 7.500%, 09/15/17 532,120
459,000 Calfrac Holdings, LP* 7.500%, 12/01/20 481,950
424,000 Carrizo Oil & Gas, Inc.* 8.625%, 10/15/18 454,740
51,000 Clayton Williams Energy, Inc.* 7.750%, 04/01/19 51,255
245,000 Complete Production Services, Inc.µ 8.000%, 12/15/16 259,700

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
385,000 Comstock Resources, Inc.µ 8.375%, 10/15/17 $ 408,100
296,000 Concho Resources, Inc.µ 8.625%, 10/01/17 328,560
306,000 EXCO Resources, Inc.µ 7.500%, 09/15/18 311,737
Frontier Oil Corp.
372,000 8.500%, 09/15/16µ 405,480
50,000 6.875%, 11/15/18 52,500
190,000 GulfMark Offshore, Inc.µ 7.750%, 07/15/14 194,750
343,000 Helix Energy Solutions Group, Inc.µ* 9.500%, 01/15/16 365,295
124,000 Holly Corp.µ 9.875%, 06/15/17 140,430
179,000 Hornbeck Offshore Services, Inc.µ 8.000%, 09/01/17 185,713
245,000 Pride International, Inc.µ 8.500%, 06/15/19 308,232
245,000 SEACOR Holdings, Inc. 7.375%, 10/01/19 265,208
398,000 SESI, LLCµ 6.875%, 06/01/14 408,447
233,000 SM Energy Company* 6.625%, 02/15/19 241,155
Swift Energy Companyµ
330,000 8.875%, 01/15/20 363,000
153,000 7.125%, 06/01/17 157,590
275,000 Trinidad Drilling, Ltd.µ* 7.875%, 01/15/19 292,875
146,000 Whiting Petroleum Corp.µ 6.500%, 10/01/18 153,300
8,435,172
Financials (0.2%)
147,000 AON Corp. 8.205%, 01/01/27 166,861
128,000 Janus Capital Group, Inc.µ 6.700%, 06/15/17 140,320
Leucadia National Corp.µ
474,000 8.125%, 09/15/15 528,510
75,000 7.125%, 03/15/17 79,125
275,000 Nuveen Investments, Inc. 10.500%, 11/15/15 287,719
OMEGA Healthcare Investors, Inc.
193,000 7.500%, 02/15/20µ 206,992
122,000 6.750%, 10/15/22* 124,593
1,534,120
Health Care (0.5%)
122,000 Bio-Rad Laboratories, Inc. 8.000%, 09/15/16 136,335
122,000 Community Health Systems, Inc. 8.875%, 07/15/15 125,050
333,000 DaVita, Inc.µ 6.625%, 11/01/20 343,406
459,000 Endo Pharmaceuticals Holdings, Inc.µ* 7.000%, 12/15/20 472,770
459,000 Giant Funding Corp.µ* 8.250%, 02/01/18 478,507
184,000 HCA, Inc.* 7.750%, 05/15/21 193,200
HealthSouth Corp.µ
168,000 7.750%, 09/15/22 179,130
135,000 7.250%, 10/01/18 143,100
Mylan, Inc.*
264,000 7.625%, 07/15/17 290,400
199,000 7.875%, 07/15/20 220,890
275,000 Talecris Biotherapeutics Holdings Corp.µ 7.750%, 11/15/16 303,875
Valeant Pharmaceuticals International, Inc.*
379,000 7.000%, 10/01/20 374,263
214,000 7.250%, 07/15/22 211,593
64,000 6.750%, 10/01/17 64,000
542,000 Warner Chilcott Company, LLC* 7.750%, 09/15/18 573,842
4,110,361
Industrials (0.7%)
184,000 Abengoa Finance SAU* 8.875%, 11/01/17 187,680
BE Aerospace, Inc.
275,000 8.500%, 07/01/18µ 307,312
21,000 6.875%, 10/01/20 22,208
Belden, Inc.
260,000 7.000%, 03/15/17µ 269,750
61,000 9.250%, 06/15/19 68,473
156,000 Clean Harbors, Inc.* 7.625%, 08/15/16 167,700
Deluxe Corp.µ
336,000 7.000%, 03/15/19* 340,200
284,000 7.375%, 06/01/15 295,715
253,000 Dycom Investments, Inc.* 7.125%, 01/15/21 262,804
144,000 Esterline Technologies Corp.µ 7.000%, 08/01/20 154,440
138,000 FTI Consulting, Inc.* 6.750%, 10/01/20 141,450
184,000 Gardner Denver, Inc. 8.000%, 05/01/13 184,690
GEO Group, Inc.
153,000 6.625%, 02/15/21* 153,382
46,000 7.750%, 10/15/17 49,450
242,000 GeoEye, Inc.µ 8.625%, 10/01/16 257,730

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
275,000 Great Lakes Dredge & Dock Corp.µ* 7.375%, 02/01/19 $ 282,562
98,000 H&E Equipment Services, Inc.µ 8.375%, 07/15/16 102,288
Huntington Ingalls Industries, Inc.*
15,000 7.125%, 03/15/21 15,863
15,000 6.875%, 03/15/18 15,863
264,000 Interline Brands, Inc.µ 7.000%, 11/15/18 273,240
122,000 Manitowoc Company, Inc. 8.500%, 11/01/20 134,200
Oshkosh Corp.
184,000 8.500%, 03/01/20 206,080
122,000 8.250%, 03/01/17 135,267
474,000 Spirit AeroSystems Holdings, Inc.µ 7.500%, 10/01/17 516,660
149,000 SPX Corp.µ 7.625%, 12/15/14 165,576
459,000 Terex Corp. 8.000%, 11/15/17 487,687
Triumph Group, Inc.
153,000 8.625%, 07/15/18µ 170,021
125,000 8.000%,
11/15/17 ~ 134,063
398,000 Tutor Perini Corp.µ* 7.625%, 11/01/18 407,950
213,000 WESCO Distribution, Inc.µ 7.500%, 10/15/17 220,987
6,131,291
Information Technology (0.5%)
Advanced Micro Devices, Inc.µ
367,000 7.750%, 08/01/20 384,433
298,000 8.125%, 12/15/17 316,625
Amkor Technology, Inc.
459,000 9.250%, 06/01/16µ 484,245
184,000 7.375%, 05/01/18 194,120
86,000 Anixter International, Inc.µ 5.950%, 03/01/15 87,075
190,000 Equinix, Inc.µ 8.125%, 03/01/18 206,625
31,000 Fidelity National Information Services, Inc. 7.875%, 07/15/20 34,410
12,000 Hynix Semiconductor, Inc.* 7.875%, 06/27/17 12,766
489,000 iGATE Corp.* 9.000%, 05/01/16 503,670
Jabil Circuit, Inc.µ
336,000 8.250%, 03/15/18 387,240
61,000 7.750%, 07/15/16 69,540
222,000 Lender Processing Services, Inc.µ 8.125%, 07/01/16 229,770
153,000 Lexmark International, Inc.µ 6.650%, 06/01/18 166,271
410,000 MEMC Electronic Materials, Inc.* 7.750%, 04/01/19 427,937
336,000 Sanmina-SCI Corp.*† 7.000%, 05/15/19 334,740
214,000 Seagate Technology* 6.875%, 05/01/20 218,280
199,000 ViaSat, Inc. 8.875%, 09/15/16 215,169
581,000 Xerox Corp. 8.000%, 02/01/27 590,858
4,863,774
Materials (0.4%)
168,000 Allegheny Ludlum Corp. 6.950%, 12/15/25 182,944
53,000 Ashland, Inc. 9.125%, 06/01/17 61,546
92,000 Ball Corp. 7.375%, 09/01/19 100,165
110,000 Boise Cascade Holdings, LLC 7.125%, 10/15/14 110,275
298,000 Clearwater Paper Corp.* 7.125%, 11/01/18 311,410
392,000 Greif, Inc.µ 7.750%, 08/01/19 432,180
169,000 Nalco Holding Company 8.250%, 05/15/17 184,844
173,000 Neenah Paper, Inc. 7.375%, 11/15/14 176,460
489,000 Sealed Air Corp.µ* 6.875%, 07/15/33 493,384
224,000 Silgan Holdings, Inc.µ 7.250%, 08/15/16 242,200
Steel Dynamics, Inc.
492,000 7.750%, 04/15/16µ 528,900
61,000 7.625%, 03/15/20 67,100
153,000 Texas Industries, Inc. 9.250%, 08/15/20 165,623
Union Carbide Corp.µ
245,000 7.500%, 06/01/25 272,838
190,000 7.875%, 04/01/23 217,856
3,547,725
Telecommunication Services (0.3%)
288,000 CenturyLink, Inc.µ 6.875%, 01/15/28 277,759
Frontier Communications Corp.
373,000 9.000%, 08/15/31µ 386,055
153,000 8.250%, 04/15/17 166,579
456,000 MetroPCS Wireless, Inc.µ 7.875%, 09/01/18 493,620
367,000 Qwest Communications International, Inc.µ 7.750%, 02/15/31 393,607
Windstream Corp.*

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Schedule of Investments April 30, 2011 (Unaudited)

PRINCIPAL — AMOUNT VALUE
538,000 7.750%, 10/15/20µ $ 572,970
184,000 7.500%, 04/01/23 187,680
2,478,270
Utilities (0.1%)
Calpine Corp.*
229,000 7.875%, 07/31/20 247,892
199,000 7.500%, 02/15/21 211,438
459,330
TOTAL CORPORATE BONDS 39,760,340
U.S. Government and Agency Securities (0.0%)
United States Treasury
Note ~
214,000 1.000%, 03/31/12 215,506
110,000 0.875%, 01/31/12 110,580
TOTAL U.S. GOVERNMENT AND AGENCY SECURITIES 326,086
Sovereign Bonds (0.1%)
Federal Republic of Brazil
87,000 BRL 10.000%, 01/01/12 562,133
37,000 BRL 10.000%, 01/01/13 233,519
TOTAL SOVEREIGN BONDS 795,652
NUMBER OF
CONTRACTS VALUE
Purchased Options (0.9%)#
Consumer Discretionary (0.2%)
260 Amazon.com, Inc. Call, 01/19/13, Strike $180.00 1,091,350
Information Technology (0.7%)
150 Apple, Inc. Call, 01/19/13, Strike $290.00 1,414,875
2,650 EMC Corp. Call, 01/19/13, Strike $25.00 1,503,875
2,400 Oracle Corp. Call, 01/19/13, Strike $30.00 2,076,000
1,250 QUALCOMM, Inc. Call, 01/19/13, Strike $55.00 1,128,125
6,122,875
TOTAL PURCHASED OPTIONS 7,214,225
TOTAL SYNTHETIC CONVERTIBLE SECURITIES (Cost $44,478,935) 48,096,303
NUMBER OF
SHARES VALUE
CONVERTIBLE PREFERRED STOCKS (14.7%)
Consumer Discretionary (0.5%)
38,966 Stanley Black & Decker, Inc. 4.750% 4,596,040
Consumer Staples (3.4%)
460,000 Archer-Daniels-Midland Companyµ 6.250% 21,537,200
76,000 Bunge, Ltd. 4.875% 8,113,000
29,650,200
Energy (1.5%)
180,000 Apache Corp. 6.000% 12,668,400
Financials (5.5%)
350,000 Affiliated Managers Group, Inc. 5.150% 15,640,625
15,500 Bank of America Corp.µ 7.250% 16,182,000
64,000 MetLife, Inc. 5.000% 5,602,560
9,100 Wells Fargo & Companyµ 7.500% 9,823,268
47,248,453
Materials (2.6%)
237,800 Vale, SA 6.750% 22,596,118
Utilities (1.2%)
190,000 NextEra Energy, Inc. 7.000% 9,861,000
TOTAL CONVERTIBLE PREFERRED STOCKS (Cost $112,112,676) 126,620,211
NUMBER OF
UNITS VALUE
STRUCTURED EQUITY-LINKED SECURITIES (2.5%)+*
Energy (1.3%)
225,000 Barclays Capital, Inc. (Nabors Industries, Ltd.) 12.000%, 06/04/11 5,670,000
173,000 Deutsche Bank, AG (Chesapeake Energy Corp.)† 8.000%, 01/24/12 5,709,000
11,379,000
Materials (1.2%)
97,000 Credit Suisse Group (Barrick Gold Corp.) 11.000%, 05/24/11 4,939,240

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Schedule of Investments April 30, 2011 (Unaudited)

NUMBER OF — UNITS VALUE
107,500 Goldman Sachs Group, Inc. (Goldcorp, Inc.) 12.000%, 07/20/11 $ 5,057,875
9,997,115
TOTAL STRUCTURED EQUITY-LINKED SECURITIES (Cost $20,086,697) 21,376,115
NUMBER OF
SHARES VALUE
COMMON STOCKS (2.4%)
Financials (0.1%)
13,850 American International Group, Inc.# 431,427
Health Care (1.5%)
354,765 Merck & Company, Inc.µ 12,753,802
Industrials (0.8%)
175,608 Avery Dennison Corp.µ 7,329,878
TOTAL COMMON STOCKS (Cost $22,278,595) 20,515,107
SHORT TERM INVESTMENT (6.8%)
58,417,794 Fidelity Prime Money Market Fund - Institutional Class (Cost $58,417,794) 58,417,794
TOTAL INVESTMENTS (128.9%) (Cost $1,039,699,965) 1,108,959,383
LIABILITIES, LESS OTHER ASSETS (-28.9%) (248,315,513 )
NET ASSETS APPLICABLE TO COMMON SHAREHOLDERS (100.0%) $ 860,643,870

NOTES TO SCHEDULE OF INVESTMENTS

| µ | Security, or portion of security, is held in a segregated
account as collateral for note payable aggregating a total value
of $595,042,418. $189,665,592 of the collateral has been
re-registered by the counterparty. |
| --- | --- |
| * | Securities issued and sold pursuant to a Rule 144A
transaction are excepted from the registration requirement of
the Securities Act of 1933, as amended. These securities may
only be sold to qualified institutional buyers
(“QIBs”), such as the fund. Any resale of these
securities must generally be effected through a sale that is
registered under the Act or otherwise exempted from such
registration requirements. At April 30, 2011, the value of
144A securities that could not be exchanged to the registered
form is $94,415,594 or 11.0% of net assets applicable to common
shareholders. |
| ‡ | Variable rate or step bond security. The rate shown is the rate
in effect at April 30, 2011. |
| ~ | Security, or portion of security, is segregated as collateral
(or potential collateral for future transactions) for written
options and swaps. The aggregate value of such securities
aggregate a total value of $7,532,789. |
| † | Security or a portion of the security purchased on a delayed
delivery or when-issued basis. |
| § | Securities exchangeable or convertible into securities of one or
more entities that are different than the issuer. Each entity is
identified in the parenthetical. |
| # | Non-income producing security. |
| + | Structured equity-linked securities are designed to simulate the
characteristics of the equity security in the parenthetical. |

FOREIGN CURRENCY ABBREVIATIONS

BRL Brazilian Real
GBP British Pound Sterling

Note: Value for securities denominated in foreign currencies is shown in U.S. dollars. The principal amount for such securities is shown in the respective foreign currency. The date on options represents the expiration date of the option contract. The option contract may be exercised at any date on or before the date shown.

INTEREST RATE SWAPS

FIXED RATE FLOATING RATE TERMINATION NOTIONAL UNREALIZED — APPRECIATION/
COUNTERPARTY (FUND PAYS) (FUND RECEIVES) DATE AMOUNT (DEPRECIATION)
BNP Paribas, SA 2.4300% quarterly 3 month Libor 04/14/14 $ 80,000,000 $ (2,972,894 )
BNP Paribas, SA 1.8650% quarterly 3 month Libor 04/14/12 55,000,000 (847,288 )
BNP Paribas, SA 1.8525% quarterly 3 month Libor 09/14/12 38,700,000 (819,125 )
$ (4,639,307 )

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Statement of Assets and Liabilities April 30, 2011 (Unaudited)

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ASSETS — Investments in securities, at value (cost $1,039,699,965) $ 1,108,959,383
Receivables:
Accrued interest and dividends 14,386,445
Investments sold 174,595
Fund shares sold 1,105,070
Prepaid expenses 432,182
Other assets 355,754
Total assets 1,125,413,429
LIABILITIES
Unrealized depreciation on interest rate swaps 4,639,307
Payables:
Note payable 234,000,000
Investments purchased 25,020,887
Affiliates:
Investment advisory fees 707,291
Deferred compensation to trustees 161,126
Financial accounting fees 10,077
Trustees’ fees and officer compensation 15,977
Other accounts payable and accrued liabilities 214,894
Total liabilities 264,769,559
NET ASSETS APPLICABLE TO COMMON SHAREHOLDERS $ 860,643,870
COMPOSITION OF NET ASSETS APPLICABLE TO COMMON
SHAREHOLDERS
Common stock, no par value, unlimited shares authorized
65,081,098 shares issued and outstanding $ 882,716,880
Undistributed net investment income (loss) (29,426,313 )
Accumulated net realized gain (loss) on investments, foreign
currency transactions and interest rate swaps (57,267,149 )
Unrealized appreciation (depreciation) of investments, foreign
currency translations and interest rate swaps 64,620,452
NET ASSETS APPLICABLE TO COMMON SHAREHOLDERS $ 860,643,870
Net asset value per common shares based upon
65,081,098 shares issued and outstanding $ 13.22

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Statement of Operations Six Months Ended April 30, 2011 (Unaudited)

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INVESTMENT INCOME — Interest $ 25,633,228
Dividends 5,784,485
Securities lending income 45,438
Total investment income 31,463,151
EXPENSES
Investment advisory fees 4,076,058
Interest expense and related fees 1,599,547
Deferred debt structuring fee 371,917
Financial accounting fees 58,021
Audit fees 56,289
Printing and mailing fees 43,989
Accounting fees 36,016
Registration fees 35,605
Trustees’ fees and officer compensation 34,927
Custodian fees 30,540
Transfer agent fees 15,113
Legal fees (9,271 )
Other 33,500
Total expenses 6,382,251
NET INVESTMENT INCOME (LOSS) 25,080,900
REALIZED AND UNREALIZED GAIN (LOSS)
Net realized gain (loss) from:
Investments, excluding purchased options (10,051,422 )
Purchased options (618,016 )
Foreign currency transactions 26,496
Interest rate swaps (1,602,034 )
Change in net unrealized appreciation/(depreciation) on:
Investments, excluding purchased options 44,281,878
Purchased options 1,445,633
Foreign currency translations (12,916 )
Interest rate swaps 2,134,018
NET GAIN (LOSS) 35,603,637
NET INCREASE (DECREASE) IN NET ASSETS APPLICABLE TO COMMON
SHAREHOLDERS RESULTING FROM OPERATIONS $ 60,684,537

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Statements of Changes in Net Assets

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(UNAUDITED) — SIX MONTHS YEAR ENDED
ENDED OCTOBER 31,
APRIL 30, 2011 2010
OPERATIONS
Net investment income (loss) $ 25,080,900 $ 52,876,350
Net realized gain (loss) (12,244,976 ) 484,320
Change in unrealized appreciation/(depreciation) 47,848,613 71,251,957
Net increase (decrease) in net assets applicable to common
shareholders resulting from operations 60,684,537 124,612,627
DISTRIBUTIONS TO COMMON SHAREHOLDERS FROM
Net investment income (36,079,315 ) (57,534,444 )
Return of capital — (8,429,372 )
Net decrease in net assets from distributions to common
shareholders (36,079,315 ) (65,963,816 )
CAPITAL STOCK TRANSACTIONS
Proceeds from common shares sold 29,820,432 81,812,245
Offering costs on common shares (92,902 ) (115,957 )
Reinvestment of distributions resulting in the issuance of
common stock 4,956,754 9,302,173
Net increase (decrease) in net assets from capital stock
transactions 34,684,284 90,998,461
TOTAL INCREASE (DECREASE) IN NET ASSETS APPLICABLE TO COMMON
SHAREHOLDERS 59,289,506 149,647,272
NET ASSETS APPLICABLE TO COMMON SHAREHOLDERS
Beginning of period $ 801,354,364 $ 651,707,092
End of period 860,643,870 801,354,364
Undistributed net investment income (loss) $ (29,426,313 ) $ (18,427,898 )

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Statement of Cash Flows Six Months Ended April 30, 2011 (Unaudited)

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CASH FLOWS FROM OPERATING ACTIVITIES: — Net increase/(decrease) in net assets from operations $ 60,684,537
Adjustments to reconcile net increase/(decrease) in net assets
from operations to net cash used for operating activities:
Purchase of investment securities (299,187,678 )
Net proceeds from disposition of short term investments (36,361,759 )
Proceeds from disposition of investment securities 276,639,674
Amortization and accretion of fixed-income securities (833,750 )
Net realized gains/losses from investments, excluding purchased
options 10,051,422
Net realized gains/losses from purchased options 618,016
Change in unrealized appreciation or depreciation on
investments, excluding purchased options (44,281,878 )
Change in unrealized appreciation or depreciation on purchased
options (1,445,633 )
Change in unrealized appreciation or depreciation on interest
rate swaps (2,134,018 )
Net change in assets and liabilities:
(Increase)/decrease in assets:
Accrued interest and dividends receivable (608,876 )
Prepaid expenses (211,316 )
Other assets (218,443 )
Increase/(decrease) in liabilities:
Payables to affiliates 81,403
Other accounts payable and accrued liabilities (161,098 )
Net cash provided by/(used in) operating activities $ (37,369,397 )
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from common shares sold 29,995,937
Offering costs related to common shares sold (92,902 )
Distributions to common shareholders (31,122,561 )
Net increase/(decrease) in due to custodian bank (2,411,077 )
Proceeds from note payable 41,000,000
Net cash provided by/(used in) financing activities $ 37,369,397
Cash at beginning of period $ —
Cash at end of period $ —
Supplemental disclosure
Cash paid for interest and related fees $ 1,615,154
Non-cash financing activities not included herein consists of
reinvestment of dividends and distributions of common stock: $ 4,956,754

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Notes to Financial Statements

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Note 1 – Organization and Significant Accounting Policies

Organization. Calamos Convertible Opportunities and Income Fund (the “Fund”) was organized as a Delaware statutory trust on April 17, 2002 and is registered under the Investment Company Act of 1940 (the “1940 Act”) as a diversified, closed-end management investment company. The Fund commenced operations on June 26, 2002. The Fund’s investment objective is to provide total return through a combination of capital appreciation and current income. Under normal circumstances, the Fund will invest at least 80% of its managed assets in a diversified portfolio of convertibles and non-convertible income securities. “Managed assets” means the Fund’s total assets (including any assets attributable to any leverage that may be outstanding) minus total liabilities (other than debt representing financial leverage).

Fund Valuation. The valuation of the Fund’s securities is in accordance with policies and procedures adopted by and under the ultimate supervision of the board of trustees.

Fund securities that are traded on U.S. securities exchanges, except option securities, are valued at the last current reported sales price at the time a Fund determines its net asset value (“NAV”). Securities traded in the over-the-counter market and quoted on The NASDAQ Stock Market are valued at the NASDAQ Official Closing Price, as determined by NASDAQ, or lacking a NASDAQ Official Closing Price, the last current reported sale price on NASDAQ at the time the Fund determines its NAV.

When a last sale or closing price is not available, equity securities, other than option securities, that are traded on a U.S. securities exchange and other equity securities traded in the over-the-counter market are valued at the mean between the most recent bid and asked quotations in accordance with guidelines adopted by the board of trustees. Each option security traded on a U.S. securities exchange is valued at the mid-point of the consolidated bid/ask quote for the option security, also in accordance with guidelines adopted by the board of trustees. Each over-the-counter option that is not traded through the Options Clearing Corporation is valued based on a quotation provided by the counterparty to such option under the ultimate supervision of the board of trustees.

Fixed income securities, certain convertible preferred securities, and non-exchange traded derivatives are normally valued by independent pricing services or by dealers or brokers who make markets in such securities. Valuations of such fixed income securities, certain convertible preferred securities, and non-exchange traded derivatives consider yield or price of equivalent securities of comparable quality, coupon rate, maturity, type of issue, trading characteristics and other market data and do not rely exclusively upon exchange or over-the-counter prices.

Trading on European and Far Eastern exchanges and over-the-counter markets is typically completed at various times before the close of business on each day on which the New York Stock Exchange (“NYSE”) is open. Each security trading on these exchanges or over-the-counter markets may be valued utilizing a systematic fair valuation model provided by an independent pricing service approved by the board of trustees. The valuation of each security that meets certain criteria in relation to the valuation model is systematically adjusted to reflect the impact of movement in the U.S. market after the foreign markets close. Securities that do not meet the criteria, or that are principally traded in other foreign markets, are valued as of the last reported sale price at the time the Fund determines its NAV, or when reliable market prices or quotations are not readily available, at the mean between the most recent bid and asked quotations as of the close of the appropriate exchange or other designated time. Trading of foreign securities may not take place on every NYSE business day. In addition, trading may take place in various foreign markets on Saturdays or on other days when the NYSE is not open and on which the Fund’s NAV is not calculated.

If the pricing committee determines that the valuation of a security in accordance with the methods described above is not reflective of a fair value for such security, the security is valued at a fair value by the pricing committee, under the ultimate supervision of the board of trustees, following the guidelines and/or procedures adopted by the board of trustees.

The Fund also may use fair value pricing, pursuant to guidelines adopted by the board of trustees and under the ultimate supervision of the board of trustees, if trading in the security is halted or if the value of a security it holds is materially affected by events occurring before the Fund’s pricing time but after the close of the primary market or exchange on which the security is listed. Those procedures may utilize valuations furnished by pricing services approved by the board of trustees, which may be based on market transactions for comparable securities and various relationships between securities that are generally recognized by institutional traders, a computerized matrix system, or appraisals derived from information concerning the securities or similar securities received from recognized dealers in those securities.

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Notes to Financial Statements

When fair value pricing of securities is employed, the prices of securities used by a Fund to calculate its NAV may differ from market quotations or official closing prices. In light of the judgment involved in fair valuations, there can be no assurance that a fair value assigned to a particular security is accurate.

Investment Transactions. Investment transactions are recorded on a trade date basis. Net realized gains and losses from investment transactions are reported on an identified cost basis. Interest income is recognized using the accrual method and includes accretion of original issue and market discount and amortization of premium. Dividend income is recognized on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information becomes available after the ex-dividend date.

Foreign Currency Translation. Values of investments and other assets and liabilities denominated in foreign currencies are translated into U.S. dollars using a rate quoted by a major bank or dealer in the particular currency market, as reported by a recognized quotation dissemination service.

The Fund does not isolate that portion of the results of operations resulting from changes in foreign exchange rates on investments from the fluctuations arising from changes in market prices of securities held. Such fluctuations are included with the net realized and unrealized gain or loss from investments.

Reported net realized foreign currency gains or losses arise from disposition of foreign currency, the difference in the foreign exchange rates between the trade and settlement dates on securities transactions, and the difference between the amounts of dividends, interest and foreign withholding taxes recorded on the ex-date or accrual date and the U.S. dollar equivalent of the amounts actually received or paid. Net unrealized foreign exchange gains and losses arise from changes (due to the changes in the exchange rate) in the value of foreign currency and other assets and liabilities denominated in foreign currencies held at period end.

Allocation of Expenses Among Funds. Expenses directly attributable to the Fund are charged to the Fund; certain other common expenses of Calamos Advisors Trust, Calamos Investment Trust, Calamos Convertible Opportunities and Income Fund, Calamos Convertible and High Income Fund, Calamos Strategic Total Return Fund, Calamos Global Total Return Fund and Calamos Global Dynamic Income Fund are allocated proportionately among each fund to which the expenses relate in relation to the net assets of each fund or on another reasonable basis.

Use of Estimates. The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from those estimates.

Other Assets. Other assets include amounts of deferred compensation to trustees and certain recoverable legal expenses under an insurance policy.

Income Taxes. No provision has been made for U.S. income taxes because the Fund’s policy is to continue to qualify as a regulated investment company under the Internal Revenue Code of 1986, as amended, and distribute to shareholders substantially all of its taxable income and net realized gains.

Dividends and distributions paid to shareholders are recorded on the ex-dividend date. The amount of dividends and distributions from net investment income and net realized capital gains is determined in accordance with federal income tax regulations, which may differ from U.S. generally accepted accounting principles. To the extent these “book/tax” differences are permanent in nature, such amounts are reclassified within the capital accounts based on their federal tax-basis treatment. These differences are primarily due to differing treatments for foreign currency transactions, contingent payment debt instruments and methods of amortizing and accreting on fixed income securities. The financial statements are not adjusted for temporary differences.

The Fund recognized no liability for uncertain tax positions. A reconciliation is not provided as the beginning and ending amounts of unrecognized benefits are zero, with no interim additions, reductions or settlements. Tax years 2007 – 2009 remain subject to examination by the U.S. and the State of Illinois tax jurisdictions.

Indemnifications. Under the Fund’s organizational documents, the Fund is obligated to indemnify its officers and trustees against certain liabilities incurred by them by reason of having been an officer or trustee of the Fund. In addition, in the normal course of business, the Fund may enter into contracts that provide general indemnifications to other parties. The Fund’s maximum exposure under

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Notes to Financial Statements

these arrangements is unknown as this would involve future claims that may be made against the Fund that have not yet occurred. Currently, the Fund’s management expects the risk of material loss in connection to a potential claim to be remote.

Note 2 – Investment Adviser and Transactions With Affiliates Or Certain Other Parties

Pursuant to an investment advisory agreement with Calamos Advisors LLC (“Calamos Advisors”), the Fund pays an annual fee, payable monthly, equal to 0.80% based on the average weekly managed assets.

Pursuant to a financial accounting services agreement, during the period the Fund paid Calamos Advisors a fee for financial accounting services payable monthly at the annual rate of 0.0175% on the first $1 billion of combined assets, 0.0150% on the next $1 billion of combined assets and 0.0110% on combined assets above $2 billion (for purposes of this calculation “combined assets” means the sum of the total average daily net assets of Calamos Investment Trust, Calamos Advisors Trust, and the total average weekly managed assets of Calamos Convertible and High Income Fund, Calamos Strategic Total Return Fund, Calamos Convertible Opportunities and Income Fund, Calamos Global Total Return Fund and Calamos Global Dynamic Income Fund). Financial accounting services include, but are not limited to, the following: managing expenses and expense payment processing; monitoring the calculation of expense accrual amounts; calculating, tracking and reporting tax adjustments on all assets; and monitoring trustee deferred compensation plan accruals and valuations. The Fund pays its pro rata share of the financial accounting services fee payable to Calamos Advisors based on its relative portion of combined assets used in calculating the fee.

The Fund reimburses Calamos Advisors for a portion of compensation paid to the Fund’s Chief Compliance Officer. This compensation is reported as part of “Trustees’ fees and officer compensation” expense on the Statement of Operations.

A trustee and certain officers of the Fund are also officers and directors of Calamos Advisors. Such trustee and officers serve without direct compensation from the Fund.

The Fund has adopted a deferred compensation plan (the “Plan”). Under the Plan, a trustee who is not an “interested person” (as defined in the 1940 Act) and has elected to participate in the Plan (a “participating trustee”) may defer receipt of all or a portion of his compensation from the Fund. The deferred compensation payable to the participating trustee is credited to the trustee’s deferral account as of the business day such compensation would have been paid to the participating trustee. The value of amounts deferred for a participating trustee is determined by reference to the change in value of Class I shares of one or more funds of Calamos Investment Trust designated by the participant. The value of the account increases with contributions to the account or with increases in the value of the measuring shares, and the value of the account decreases with withdrawals from the account or with declines in the value of the measuring shares. Deferred compensation of $161,126 is included in “Other assets” on the Statement of Assets and Liabilities at April 30, 2011. The Fund’s obligation to make payments under the Plan is a general obligation of the Fund and is included in “Payable for deferred compensation to trustees” on the Statement of Assets and Liabilities at April 30, 2011.

Note 3 – Investments

The cost of purchases and proceeds from sale of long-term investments, for the period ended April 30, 2011 were as follows:

Cost of purchases 257,417,252
Proceeds from sales 188,089,377

The following information is presented on a federal income tax basis as of April 30, 2011. Differences between the cost basis under U.S. generally accepted accounting principles and federal income tax purposes are primarily due to temporary differences.

The cost basis of investments for federal income tax purposes at April 30, 2011 was as follows:

Cost basis of investments $
Gross unrealized appreciation 67,016,787
Gross unrealized depreciation (23,020,005 )
Net unrealized appreciation (depreciation) $ 43,996,782

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Note 4 – Income Taxes

The Fund intends to make monthly distributions from its income available for distribution, which consists of the Fund’s dividends and interest income after payment of Fund expenses, and net realized gains on stock investments. At least annually, the Fund intends to distribute all or substantially all of its net realized capital gains, if any. Distributions are recorded on the ex-dividend date. The Fund distinguishes between distributions on a tax basis and a financial reporting basis. Accounting principles generally accepted in the United States of America require that only distributions in excess of tax basis earnings and profits be reported in the financial statements as a return of capital. Permanent differences between book and tax accounting relating to distributions are reclassified to paid-in-capital. For tax purposes, distributions from short-term capital gains are considered to be from ordinary income. Distributions in any year may include a return of capital component.

The tax character of distributions for the period ended April 30, 2011 will be determined at the end of each Fund’s current fiscal year. Distributions during the fiscal period ended October 31, 2010 were characterized for federal income tax purposes as follows:

YEAR ENDED
OCTOBER 31, 2010
Distributions paid from:
Ordinary income $ 57,534,444
Long-term capital gains —
Return of Capital 8,429,372

As of October 31, 2010, the components of accumulated earnings/(loss) on a tax basis were as follows:

Undistributed ordinary income $
Undistributed capital gains —
Total undistributed earnings —
Accumulated capital and other losses (47,064,354)
Net unrealized gains/(losses) 511,393
Total accumulated earnings/(losses) (46,552,961)
Other (125,271)
Paid-in capital 848,032,596
Net assets applicable to common shareholders $ 801,354,364

As of October 31, 2010, the Fund had capital loss carryforwards which, if not used, will expire as follows:

2017 (45,276,397)
2018 (1,787,957)

Note 5 – Common Shares

There are unlimited common shares of beneficial interest authorized and 65,081,098 shares outstanding at April 30, 2011. Calamos Advisors owned 16,280 of the outstanding shares at April 30, 2011. Transactions in common shares were as follows:

APRIL 30, 2011 OCTOBER 31, 2010
Beginning shares 62,431,622 55,104,427
Shares sold 2,265,859 6,567,190
Shares issued through reinvestment of distributions 383,617 760,005
Ending shares 65,081,098 62,431,622

Notice is hereby given in accordance with Section 23(c) of the Investment Company Act of 1940 that the Fund may from time to time purchase its shares of common stock in the open market.

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Notes to Financial Statements

The Fund also may offer and sell common shares from time to time at an offering price equal to or in excess of the net asset value per share of the Fund’s common shares at the time such common shares are initially sold. Transactions for the first six months of the fiscal year had net proceeds received in excess of net value of $354,312.

Note 6 – Derivative Instruments

Foreign Currency Risk. The Fund engaged in portfolio hedging with respect to changes in currency exchange rates by entering into foreign currency contracts to purchase or sell currencies. A forward foreign currency contract is a commitment to purchase or sell a foreign currency at a future date at a negotiated forward rate. Risks associated with such contracts include, among other things, movement in the value of the foreign currency relative to the U.S. dollar and the ability of the counterparty to perform. The net unrealized gain, if any, represents the credit risk to the Fund on a forward foreign currency contract. The contracts are valued daily at forward foreign exchange rates and an unrealized gain or loss is recorded. The Fund realizes a gain or loss when a position is closed or upon settlement of the contracts. There were no open forward currency contracts at April 30, 2011.

Equity Risk. The Fund engages in option transactions and in doing so achieves the similar objectives to what it would achieve through the sale or purchase of individual securities. A call option, upon payment of a premium, gives the purchaser of the option the right to buy, and the seller of the option the obligation to sell, the underlying security, index or other instrument at the exercise price. A put option gives the purchaser of the option, upon payment of a premium, the right to sell, and the seller the obligation to buy, the underlying security, index, or other instrument at the exercise price.

To seek to offset some of the risk of a potential decline in value of certain long positions, the Fund may also purchase put options on individual securities, broad-based securities indexes or certain exchange traded funds (“ETFs”). The Fund may also seek to generate income from option premiums by writing (selling) options on a portion of the equity securities (including securities that are convertible into equity securities) in the Fund’s portfolio, on broad-based securities indexes, or certain ETFs.

When a Fund purchases an option, it pays a premium and an amount equal to that premium is recorded as an asset. When a Fund writes an option, it receives a premium and an amount equal to that premium is recorded as a liability. The asset or liability is adjusted daily to reflect the current market value of the option. If an option expires unexercised, the Fund realizes a gain or loss to the extent of the premium received or paid. If an option is exercised, the premium received or paid is recorded as an adjustment to the proceeds from the sale or the cost basis of the purchase. The difference between the premium and the amount received or paid on a closing purchase or sale transaction is also treated as a realized gain or loss. The cost of securities acquired through the exercise of call options is increased by premiums paid. The proceeds from securities sold through the exercise of put options are decreased by the premiums paid. Gain or loss on written options and purchased options is presented separately as net realized gain or loss on written options and net realized gain or loss on purchased options, respectively.

Interest Rate Risk. The Fund engages in interest rate swaps primarily to hedge the interest rate risk on the fund’s borrowings (see Note 7—Borrowings). An interest rate swap is a contract that involves the exchange of one type of interest rate for another type of interest rate. If interest rates rise, resulting in a diminution in the value of the Fund’s portfolio, the Fund would receive payments under the swap that would offset, in whole or in part, such diminution in value; if interest rates fall, the Fund would likely lose money on the swap transaction. Unrealized gains are reported as an asset, and unrealized losses are reported as a liability on the Statement of Assets and Liabilities. The change in value of swaps, including accruals of periodic amounts of interest to be paid or received on swaps, is reported as change in net unrealized appreciation/depreciation on interest rate swaps in the Statement of Operations. A realized gain or loss is recorded in net realized gain (loss) from interest rate swaps in the Statement of Operations upon payment or receipt of a periodic payment or termination of the swap agreements. Swap agreements are stated at fair value. Notional principal amounts are used to express the extent of involvement in these transactions, but the amounts potentially subject to credit risk are much smaller. In connection with these contracts, securities may be identified as collateral in accordance with the terms of the respective swap contracts in the event of default or bankruptcy of the Fund.

Premiums paid to or by a Fund are accrued daily and included in realized gain (loss) when paid on swaps in the accompanying Statement of Operations. The contracts are marked-to-market daily based upon third party vendor valuations and changes in value are recorded as unrealized appreciation (depreciation). Gains or losses are realized upon early termination of the contract. Risks may exceed amounts recognized in the Statement of Assets and Liabilities. These risks include changes in the returns of the underlying instruments, failure of

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Notes to Financial Statements

the counterparties to perform under the contracts’ terms, counterparty’s creditworthiness, and the possible lack of liquidity with respect to the contracts.

As of April 30, 2011, the Fund had outstanding interest rate swap agreements as listed on the Schedule of Investments.

Below are the types of derivatives in the Fund by gross value as of April 30, 2011:

ASSETS — STATEMENT OF ASSETS & LIABILITIES — STATEMENT OF ASSETS &
LIABILITIES LOCATION VALUE LIABILITIES LOCATION VALUE
Derivative Type:
Equity-Purchased options Investments in securities $ 7,214,225
Interest Rate Swaps Unrealized appreciation Unrealized depreciation on
on swaps — swaps $ 4,639,307

Volume of Derivative Activity for the Six Months Ended April 30, 2011*

Equity:
Purchased options 6,560
  • Activity during the period is measured by opened number of contracts for options and opened notional amount for swap contracts.

Note 7 – Borrowings

The Fund, with the approval of its board of trustees, including its independent trustees, has entered into a financing package that includes a Committed Facility Agreement (the “Agreement”) with BNP Paribas Prime Brokerage, Inc. (as successor to Bank of America N.A.) (“BNP”) that allows the Fund to borrow up to an initial limit of $300,000,000 and a Lending Agreement, as defined below. Borrowings under the Agreement are secured by assets of the Fund that are held with the Fund’s custodian in a separate account (the “pledged collateral”). Interest is charged at the quarterly LIBOR (London Inter-bank Offered Rate) plus .65% on the amount borrowed and .55% on the undrawn balance. For the period ended April 30, 2011, the average borrowings and the average interest rate were $208,176,796 and 1.18%, respectively. As of April 30, 2011, the amount of such outstanding borrowings is $234,000,000. The interest rate applicable to the borrowings on April 30, 2011 was 0.92%.

The Lending Agreement is a separate side-agreement between the Fund and BNP pursuant to which BNP may borrow a portion of the pledged collateral (the “Lent Securities”) in an amount not to exceed the outstanding borrowings owed by the Fund to BNP under the Agreement. The Lending Agreement is intended to permit the Fund to significantly reduce the cost of its borrowings under the Agreement. BNP may re-register the Lent Securities in its own name or in another name other than the Fund, and may pledge, re-pledge, sell, lend or otherwise transfer or use the Lent Securities with all attendant rights of ownership. (It is the Fund’s understanding that BNP will perform due diligence to determine the creditworthiness of any party that borrows Lent Securities from BNP.) The Fund may designate any security within the pledged collateral as ineligible to be a Lent Security, provided there are eligible securities within the pledged collateral in an amount equal to the outstanding borrowing owed by the Fund. During the period in which the Lent Securities are outstanding, BNP must remit payment to the Fund equal to the amount of all dividends, interest or other distributions earned or made by the Lent Securities.

Under the terms of the Lending Agreement, the Lent Securities are marked to market daily, and if the value of the Lent Securities exceeds the value of the then-outstanding borrowings owed by the Fund to BNP under the Agreement (the “Current Borrowings”), BNP must, on that day, either (1) return Lent Securities to the Fund’s custodian in an amount sufficient to cause the value of the outstanding Lent Securities to equal the Current Borrowings; or (2) post cash collateral with the Fund’s custodian equal to the difference between the value of the Lent Securities and the value of the Current Borrowings. If BNP fails to perform either of these actions as required, the Fund will recall securities, as discussed below, in an amount sufficient to cause the value of the outstanding Lent Securities to equal the Current Borrowings. The Fund can recall any of the Lent Securities and BNP shall, to the extent commercially possible, return such security or equivalent security to the Fund’s custodian no later than three business days after such request. If the Fund recalls a Lent Security pursuant to the Lending Agreement, and BNP fails to return the Lent Securities or equivalent securities in a timely fashion, BNP shall remain liable to the Fund’s custodian for the ultimate delivery of such Lent Securities, or equivalent securities, and for any buy-in costs

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that the executing broker for the sales transaction may impose with respect to the failure to deliver. The Fund shall also have the right to apply and set-off an amount equal to one hundred percent (100%) of the then-current fair market value of such Lent Securities against the Current Borrowings.

Note 8 – Synthetic Convertible Securities

The Fund may establish a “synthetic” convertible instrument by combining separate securities that possess the economic characteristics similar to a convertible security, i.e., fixed-income securities (“fixed-income component”), which may be a convertible or non-convertible security and the right to acquire equity securities (“convertible component”). The fixed-income component is achieved by investing in fixed income securities such as bonds, preferred stocks, and money market instruments. The convertible component is achieved by investing in warrants or purchased options to buy common stock at a certain exercise price, or options on a stock index. In establishing a synthetic instrument, the Fund may pool a basket of fixed-income securities and a basket of warrants or purchased options that produce the economic characteristics similar to a convertible security. Within each basket of fixed-income securities and warrants or options, different companies may issue the fixed-income and convertible components, which may be purchased separately and at different times.

The Fund may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. Convertible structured notes are fixed-income debentures linked to equity. Convertible structured notes have the attributes of a convertible security; however, the investment bank that issued the convertible note assumes the credit risk associated with the investment, rather than the issuer of the underlying common stock into which the note is convertible. Purchasing synthetic convertible securities may offer more flexibility than purchasing a convertible security.

Note 9 – When-Issued and Delayed Delivery Securities

The Fund may purchase securities on a when-issued or delayed-delivery basis. Although the payment and interest terms of these securities are established at the time the Fund enters into the commitment, the securities may be delivered and paid for a month or more after the date of purchase, when their value may have changed. The Fund makes such commitments only with the intention of actually acquiring the securities, but may sell the securities before the settlement date if Calamos Advisors deems it advisable for investment reasons. The Fund may utilize spot and forward foreign currency exchange transactions to reduce the risk inherent in fluctuations in the exchange rate between one currency and another when securities are purchased or sold on a when-issued or delayed-delivery basis.

At the time when the Fund enters into a binding obligation to purchase securities on a when-issued basis, liquid assets (cash, U.S. Government securities or other “high-grade” debt obligations) of the Fund having a value at least as great as the purchase price of the securities to be purchased will be segregated on the books of the Fund and held by the custodian throughout the period of the obligation. The use of this investment strategy may increase net asset value fluctuation.

Note 10 – Structured Equity-Linked Securities

The Fund may also invest in structured equity-linked securities created by third parties, typically investment banks. Structured equity-linked securities created by such parties may be designed to simulate the characteristics of traditional convertible securities or may be designed to alter or emphasize a particular feature. Traditional convertible securities typically offer stable cash flows with the ability to participate in capital appreciation of the underlying common stock. Because traditional convertible securities are exercisable at the option of the holder, the holder is protected against downside risk. Structured equity-linked securities may alter these characteristics by offering enhanced yields in exchange for reduced capital appreciation or less downside protection, or any combination of these features. Structured equity-linked instruments may include structured notes, equity-linked notes, mandatory convertibles and combinations of securities and instruments, such as a debt instrument combined with a forward contract. Income received from these securities is recorded as dividends on the Statement of Operations.

Note 11 – Valuations

Various inputs are used to determine the value of the Fund’s investments. These inputs are categorized into three broad levels as follows:

• Level 1 – Prices are determined using inputs from unadjusted quoted prices from active markets (including securities actively traded on a securities exchange) for identical assets.

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| • | Level 2 – Prices are determined using significant
observable market inputs other than unadjusted quoted prices,
including quoted prices of similar securities, fair value
adjustments to quoted foreign securities, interest rates, credit
risk, prepayment speeds, and other relevant data. |
| --- | --- |
| • | Level 3 – Prices reflect unobservable market
inputs (including the Fund’s own judgments about
assumptions market participants would use in determining fair
value) when observable inputs are unavailable. |

Debt securities (including U.S. government and government agency obligations) are valued based upon evaluated prices received from an independent pricing service or from a dealer or broker who makes markets in such securities. Pricing services utilize various observable market data and as such, debt securities are generally categorized as Level 2. The levels are not necessarily an indication of the risk or liquidity of the Fund’s investments.

The following is a summary of the inputs used in valuing the Fund’s holdings at fair value:

| | CONVERTIBLE OPPORTUNITIES AND
INCOME FUND — LEVEL 1 | LEVEL 2 | LEVEL 3 | TOTAL |
| --- | --- | --- | --- | --- |
| Assets: | | | | |
| Corporate Bonds | $ — | $ 610,218,777 | $ — | $ 610,218,777 |
| Convertible Bonds | | 206,476,231 | | $ 206,476,231 |
| U.S. Government and Agency Securities | | 5,008,036 | | $ 5,008,036 |
| Sovereign Bonds | | 12,230,809 | | $ 12,230,809 |
| Synthetic Convertible Securities (Corporate Bonds) | | 39,760,340 | | $ 39,760,340 |
| Synthetic Convertible Securities (U.S. Government and Agency
Securities) | | 326,086 | | $ 326,086 |
| Synthetic Convertible Securities (Sovereign Bonds) | | 795,652 | | $ 795,652 |
| Synthetic Convertible Securities (Purchased Options) | 7,214,225 | | | $ 7,214,225 |
| Convertible Preferred Stocks | 102,866,586 | 23,753,625 | | $ 126,620,211 |
| Structured Equity-Linked Securities | | 21,376,115 | | $ 21,376,115 |
| Common Stocks | 20,515,107 | | | $ 20,515,107 |
| Short Term Investment | 58,417,794 | | | $ 58,417,794 |
| | $ 189,013,712 | $ 919,945,671 | $ — | $ 1,108,959,383 |
| Liabilities: | | | | |
| Interest Rate Swaps | | 4,639,307 | | $ 4,639,307 |
| Total | $ — | $ 4,639,307 | $ — | $ 4,639,307 |

Note 12 – Legal Proceedings

The Fund, the Fund’s Board of Trustees, Calamos Advisors LLC (the “Adviser”), and the corporate parent of the Adviser have been named as defendants in putative class action complaints filed by plaintiffs in the Circuit Court of Cook County, Illinois and removed by the defendants to the United States District Court for the Northern District of Illinois or pending on appeal to the United States Court of Appeals for the Seventh Circuit related to the Fund’s redemption of its previously outstanding Auction Rate Cumulative Preferred Shares (the “ARPS”) at their liquidation preference. The complaints, captioned Brown v. Calamos, et al. and Bourrienne v. Calamos, et al., generally allege that the Fund’s Board of Trustees breached certain fiduciary duties owed to the common shareholders of the Fund by approving the redemption of the Fund’s ARPS at their liquidation preference, and by recapitalizing the Fund with debt-based borrowings that were allegedly less advantageous to the Fund’s common shareholders. The complaints also allege that Calamos and the corporate parent of Calamos aided and abetted the Trustees’ alleged breaches of fiduciary duty and were unjustly enriched as a result, while the Brown complaint also alleges that the Fund itself aided and abetted these actions and was similarly unjustly enriched as a result. Both complaints allege identical causes of action and encompass materially identical putative classes and class periods. The suits seek indeterminate monetary and punitive damages from the named defendants, as well as injunctive relief. On March 14, 2011, the judge assigned to the Brown case dismissed it, and the plaintiff filed a Notice of Appeal in the United States Court of Appeals for the Seventh Circuit, where the case is currently pending. The Bourrienne case remains pending in the United States Court for the Northern District of

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Illinois. The defendants believe that the complaints are without merit, and intend to defend themselves vigorously against these allegations.

Calamos and the corporate parent of Calamos, among other persons, also have been named as defendants in a putative class action complaint captioned Rutgers v. Calamos, et al. , which relates to the redemption of ARPS by Calamos Convertible & High Income Fund (“CHY”). The complaint, which is similar to the Brown and Bourrienne complaints, is also currently pending in the United States District Court for the Northern District of Illinois. The Rutgers complaint generally alleges that CHY’s Board of Trustees breached certain fiduciary duties owed to the common shareholders of CHY by approving the redemption of CHY’s ARPS at their liquidation preference, and by recapitalizing CHY with debt-based borrowings that were allegedly less advantageous to CHY’s common shareholders. The complaints also allege that Calamos, the corporate parent of Calamos, and CHY itself aided and abetted the Trustees’ alleged breaches of fiduciary duty and were unjustly enriched as a result. The suit seeks indeterminate monetary and punitive damages from the named defendants, as well as injunctive relief. The defendants believe that the Rutgers complaint is without merit, and intend to defend themselves vigorously against these allegations.

The Fund believes that the litigation does not have any present material adverse effect on the Fund or on the ability of Calamos to perform its obligations under its investment advisory contract with the Fund.

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Financial Highlights

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Selected data for a share outstanding throughout each period were as follows:

Six Months Ended
April 30, Year Ended October 31,
2011 2010 2009 2008 2007 2006
Net asset value, beginning of period $12.84 $11.83 $8.26 $16.38 $16.42 $16.59
Income from investment operations:
Net investment income (loss) 0.40 ** 0.91 ** 0.84 ** 1.16 ** 1.44 ** 1.50
Net realized and unrealized gain (loss) 0.54 1.22 3.88 (7.31 ) 0.97 0.81
Distributions to preferred shareholders from:
Net investment income (common share equivalent basis) — — (0.01 ) (0.13 ) (0.41 ) (0.36 )
Net realized gains (common share equivalent basis) — — — (0.12 ) (0.02 ) (0.03 )
Total from investment operations 0.94 2.13 4.71 (6.40 ) 1.98 1.92
Less distributions to common shareholders from:
Net investment income (0.57 ) (1.00 ) (0.94 ) (1.41 ) (1.55 ) (1.61 )
Net realized gains — — (0.02 ) (0.31 ) (0.47 ) (0.48 )
Return of capital — (0.14 ) (0.18 ) — — —
Capital charge resulting from issuance of common and preferred
shares and related offering costs — (a) — (a) — (a) — (a) — —
Premiums from shares sold in at the market offerings 0.01 0.02 — — — —
Net asset value, end of period $13.22 $12.84 $11.83 $8.26 $16.38 $16.42
Market value, end of period $13.55 $13.09 $11.40 $9.10 $16.90 $19.73
Total investment return based on:(b)
Net asset value 7.59% 19.12% 62.00% (42.58% ) 11.51% 10.47%
Market value 8.17% 26.02% 41.70% (38.69% ) (4.25% ) 12.81%
Net assets, end of period (000) $860,644 $801,354 $651,707 $409,035 $784,997 $771,994
Preferred shares, at redemption value ($25,000 per share
liquidation preference) (000’s omitted) $104,000 $384,000 $384,000
Ratios to average net assets applicable to common shareholders:
Net expenses(c) 1.57% (d) 1.67% 2.87% 1.92% 1.08% 1.04%
Gross expenses prior to expense and earnings credits(c) 1.57% (d) 1.71% 2.98% 2.16% 1.43% 1.42%
Net expenses, excluding interest expense 1.18% (d) 1.19% 2.36% 1.30% 1.08% 1.04%
Net investment income (loss)(c) 6.17% (d) 7.48% 8.79% 8.38% 8.83% 9.17%
Preferred share distributions —% —% 0.10% 0.92% 2.51% 2.18%
Net investment income (loss), net of preferred share
distributions from net investment income 6.17% (d) 7.48% 8.69% 7.46% 6.32% 6.99%
Portfolio turnover rate 20% 37% 30% 53% 52% 48%
Average commission rate paid $0.0104
Asset coverage per preferred share, at end of period(e) $123,350 $76,142 $75,291
Asset coverage per $1,000 of loan outstanding(f) $4,678 $5,152 $4,377 $3,745

| ** | Net investment income allocated
based on average shares method. |
| --- | --- |
| (a) | Amount equated to less than $0.005
per common share. |
| (b) | Total investment return is
calculated assuming a purchase of common stock on the opening of
the first day and a sale on the closing of the last day of the
period reported. Dividends and distributions are assumed, for
purposes of this calculation, to be reinvested at prices
obtained under the Fund’s dividend reinvestment plan. Total
return is not annualized for periods less than one year.
Brokerage commissions are not reflected. NAV per share is
determined by dividing the value of the Fund’s portfolio
securities, cash and other assets, less all liabilities, by the
total number of common shares outstanding. The common share
market price is the price the market is willing to pay for
shares of the Fund at a given time. Common share market price is
influenced by a range of factors, including supply and demand
and market conditions. |
| (c) | Does not reflect the effect of
dividend payments to Preferred Shareholders. |
| (d) | Annualized. |
| (e) | Calculated by subtracting the
Fund’s total liabilities (not including Preferred Shares)
from the Fund’s total assets and dividing this by the
number of Preferred Shares outstanding. |
| (f) | Calculated by subtracting the
Fund’s total liabilities (not including Note payable) and
preferred shares from the Fund’s total assets and dividing
this by the amount of note payable outstanding, and by
multiplying the result by 1,000. |

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Report of Independent Registered Public Accounting Firm

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To the Shareholders and Board of Trustees of Calamos Convertible Opportunities and Income Fund

We have reviewed the accompanying statement of assets and liabilities, including the schedule of investments, for Calamos Convertible Opportunities and Income Fund (the “Fund”) as of April 30, 2011, and the related statements of operations, changes in net assets, and cash flows and the financial highlights for the semi-annual period then ended. These interim financial statements and financial highlights are the responsibility of the Fund’s management.

We conducted our review in accordance with standards of the Public Company Accounting Oversight Board (United States). A review of interim financial information consists principally of applying analytical procedures and making inquiries of persons responsible for financial and accounting matters. It is substantially less in scope than an audit conducted in accordance with standards of the Public Company Accounting Oversight Board (United States), the objective of which is the expression of an opinion regarding the financial statements and financial highlights taken as a whole. Accordingly, we do not express such an opinion.

Based on our review, we are not aware of any material modifications that should be made to such interim financial statements and financial highlights for them to be in conformity with accounting principles generally accepted in the United States of America.

We have previously audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the statement of changes in net assets of the Fund for the year ended October 31, 2010 and the financial highlights for each of the five years then ended; and in our report dated December 17, 2010, we expressed an unqualified opinion on such statement of changes in net assets and financial highlights.

Chicago, Illinois

June 20, 2011

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About Closed-End Funds

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What is a Closed-End Fund?

A closed-end fund is a publicly traded investment company that raises its initial investment capital through the issuance of a fixed number of shares to investors in a public offering. Shares of a closed-end fund are listed on a stock exchange or traded in the over-the-counter market. Like all investment companies, a closed-end fund is professionally managed and offers investors a unique investment solution based on its investment objective approved by the fund’s Board of Directors.

Potential Advantages of Closed-End Fund Investing

| • | Defined Asset Pool Allows Efficient Portfolio
Management —Although closed-end fund shares trade
actively on a securities exchange, this doesn’t affect the
closed-end fund manager because there are no new investors
buying into or selling out of the fund’s portfolio. |
| --- | --- |
| • | More Flexibility in the Timing and Price of
Trades —Investors can purchase and sell shares of
closed-end funds throughout the trading day, just like the
shares of other publicly traded securities. |
| • | Lower Expense Ratios —The expense ratios of
closed-end funds are oftentimes less than those of mutual funds.
Over time, a lower expense ratio could enhance investment
performance. |
| • | Closed-End Structure Makes Sense for Less-Liquid Asset
Classes —A closed-end structure makes sense for
investors considering less-liquid asset classes, such as
high-yield bonds or micro-cap stocks. |
| • | Ability to Put Leverage to Work —Closed-end funds may
issue senior securities (such as preferred shares or debentures)
or borrow money to “leverage” their investment
positions. |
| • | No Minimum Investment Requirements |

OPEN-END MUTUAL FUNDS VERSUS CLOSED-END FUNDS

OPEN-END FUND CLOSED-END FUND
Issues new shares on an ongoing basis Generally issues a fixed number of shares
Issues common equity shares Can issue common equity securities and senior securities such as
preferred shares and bonds
Sold at NAV plus any sales charge Price determined by the marketplace
Sold through the fund’s distributor Traded in the secondary market
Fund redeems shares at NAV calculated at the close of business
day Fund does not redeem shares

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Level Rate Distribution Policy

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Using a Level Rate Distribution Policy to Promote Dependable Income and Total Return

The goal of the level rate distribution policy is to provide investors a predictable, though not assured, level of cash flow, which can either serve as a stable income stream or, through reinvestment, contribute significantly to long-term total return.

We understand the importance that investors place on the stability of dividends and their ability to contribute to long-term total return, which is why we have instituted a level rate distribution policy for the Fund. Under the policy, monthly distributions paid may include net investment income, net realized short-term capital gains and, if necessary, return of capital. In addition, a limited number of distributions per calendar year may include net realized long-term capital gains. There is no guarantee that the Fund will realize capital gains in any given year. Distributions are subject to re-characterization for tax purposes after the end of the fiscal year. All shareholders with taxable accounts will receive written notification regarding the components and tax treatment for distributions via Form 1099-DIV.

Distributions from the Fund are generally subject to Federal income taxes. For purposes of maintaining the level rate distribution policy, the Fund may realize short-term capital gains on securities that, if sold at a later date, would have resulted in long-term capital gains. Maintenance of a level rate distribution policy may increase transaction and tax costs associated with the Fund.

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Automatic Dividend Reinvestment Plan

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Maximizing Investment with an Automatic Dividend Reinvestment Plan

The Automatic Dividend Reinvestment Plan offers a simple, cost-efficient and convenient way to reinvest your dividends and capital gains distributions in additional shares of the Fund, allowing you to increase your investment in the Fund.

Potential Benefits

| • | Compounded Growth: By automatically reinvesting with the
Plan, you gain the potential to allow your dividends and capital
gains to compound over time. |
| --- | --- |
| • | Potential for Lower Commission Costs: Additional shares
are purchased in large blocks, with brokerage commissions shared
among all plan participants. There is no cost to enroll in the
Plan. |
| • | Convenience: After enrollment, the Plan is automatic and
includes detailed statements for participants. Participants can
terminate their enrollment at any time. |

Pursuant to the Plan, unless a shareholder is ineligible or elects otherwise, all dividend and capital gains on common shares distributions are automatically reinvested by BNY Mellon Asset Servicing, as agent for shareholders in administering the Plan (“Plan Agent”), in additional common shares of the Fund. Shareholders who elect not to participate in the Plan will receive all dividends and distributions payable in cash paid by check mailed directly to the shareholder of record (or, if the shares are held in street or other nominee name, then to such nominee) by Plan Agent, as dividend paying agent. Shareholders may elect not to participate in the Plan and to receive all dividends and distributions in cash by sending written instructions to Plan Agent, as dividend paying agent, at: Dividend Reinvestment Department, P.O. Box 1958, Newark, New Jersey 07101-9774. Participation in the Plan is completely voluntary and may be terminated or resumed at any time without penalty by giving notice in writing to the Plan Agent; such termination will be effective with respect to a particular dividend or distribution if notice is received prior to the record date for the applicable distribution.

The shares are acquired by the Plan Agent for the participant’s account either (i) through receipt of additional common shares from the Fund (“newly issued shares”) or (ii) by purchase of outstanding common shares on the

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Automatic Dividend Reinvestment Plan

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open market (“open-market purchases”) on the NYSE or elsewhere. If, on the payment date, the net asset value per share of the common shares is equal to or less than the market price per common share plus estimated brokerage commissions (a “market premium”), the Plan Agent will receive newly issued shares from the Fund for each participant’s account. The number of newly issued common shares to be credited to the participant’s account will be determined by dividing the dollar amount of the dividend or distribution by the greater of (i) the net asset value per common share on the payment date, or (ii) 95% of the market price per common share on the payment date.

If, on the payment date, the net asset value per common share exceeds the market price plus estimated brokerage commissions (a “market discount”), the Plan Agent has a limited period of time to invest the dividend or distribution amount in shares acquired in open-market purchases. The weighted average price (including brokerage commissions) of all common shares purchased by the Plan Agent as Plan Agent will be the price per common share allocable to each participant. If, the Plan Agent is unable to invest the full dividend amount in open-market purchases during the purchase period or if the market discount shifts to a market premium during the purchase period, the Plan Agent will cease making open-market purchases and will invest the uninvested portion of the dividend or distribution amount in newly issued shares at the close of business on the last purchase date.

The automatic reinvestment of dividends and distributions will not relieve participants of any federal, state or local income tax that may be payable (or required to be withheld) on such dividends even though no cash is received by participants.

There are no brokerage charges with respect to shares issued directly by the Fund as a result of dividends or distributions payable either in shares or in cash. However, each participant will pay a pro rata share of brokerage commissions incurred with respect to the Plan Agent’s open-market purchases in connection with the reinvestment of dividends or distributions. If a participant elects to have the Plan Agent sell part or all of his or her common shares and remit the proceeds, such participant will be charged his or her pro rata share of brokerage commissions on the shares sold, plus a $15 transaction fee. There is no direct service charge to participants in the Plan; however, the Fund reserves the right to amend the Plan to include a service charge payable by the participants.

A participant may request the sale of all of the common shares held by the Plan Agent in his or her Plan account in order to terminate participation in the Plan. If such participant elects in advance of such termination to have the Plan Agent sell part or all of his shares, the Plan Agent is authorized to deduct from the proceeds a $15.00 fee plus the brokerage commissions incurred for the transaction. A participant may re-enroll in the Plan in limited circumstances.

The terms and conditions of the Plan may be amended by the Plan Agent or the Fund at any time upon notice are required by the Plan.

This discussion of the Plan is only summary, and is qualified in its entirety to the Terms and Conditions of the Dividend Reinvestment Plan filed as part of the Fund’s registration statement.

For additional information about the Plan, please contact the Plan Agent, The Bank of New York, at 800.432.8224. If you wish to participate in the Plan and your shares are held in your own name, simply call the Plan Agent. If your shares are not held in your name, please contact your brokerage firm, bank, or other nominee to request that they participate in the Plan on your behalf. If your brokerage firm, bank, or other nominee is unable to participate on your behalf, you may request that your shares be re-registered in your own name.

We’re pleased to provide our shareholders with the additional benefit of the Fund’s Dividend Reinvestment Plan and hope that it may serve your financial plan.

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A description of the Calamos Proxy Voting Policies and Procedures and the Fund’s proxy voting record for the 12 month period ended June 30, 2010, are available free of charge upon request by calling 800.582.6959, by visiting the Calamos website at www.calamos.com, by writing Calamos at: Calamos Investments, Attn: Client Services, 2020 Calamos Court, Naperville, IL 60563. The Fund’s proxy voting record is also available free of charge by visiting the SEC website at http://www.sec.gov.

The Fund files its complete list of portfolio holdings with the SEC for the first and third quarters each fiscal year on Form N-Q. The Forms N-Q are available free of charge, upon request, by calling or writing Calamos Investments at the phone number or address provided above or by visiting the SEC website at http://www.sec.gov. You may also review or, for a fee, copy the forms at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 800.732.0330.

On June 21, 2010, the Fund submitted a CEO annual certification to the NYSE on which the Fund’s chief executive officer certified that he was not aware, as of that date, of any violation by the Fund of the NYSE’s corporate governance listing standards. In addition, the Fund’s report to the SEC on Form N-CSR contains certifications by the fund’s principal executive officer and principal financial officer as required by Rule 30a-2(a) under the 1940 Act, relating to, among other things, the quality of the Fund’s disclosure controls and procedures and internal control over financial reporting.

FOR 24 HOUR AUTOMATED SHAREHOLDER ASSISTANCE: 800.432.8224

TO OBTAIN INFORMATION ABOUT YOUR INVESTMENTS: 800.582.6959

VISIT OUR WEBSITE: www.calamos.com

INVESTMENT ADVISER:

Calamos Advisors LLC 2020 Calamos Court Naperville, IL 60563-2787

CUSTODIAN AND FUND ACCOUNTING AGENT:

State Street Bank and Trust Company 225 Franklin Street Boston, MA 02111

TRANSFER AGENT:

The Bank of New York Mellon P.O. Box 11258 Church Street Station New York, NY 10286 800.524.4458

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM:

Deloitte & Touche LLP Chicago, IL

LEGAL COUNSEL:

K&L Gates LLP Chicago, IL

2020 Calamos Court

Naperville, IL 60563-2787

800.582.6959

www.calamos.com

© 2011 Calamos Holdings LLC. All Rights Reserved.

Calamos ® and Calamos Investments ® are registered

trademarks of Calamos Holdings LLC.

CHISAN 1790 2011

XBRL Pagebreak Begin

END PAGE WIDTH PAGEBREAK

TOC /TOC link2 "ITEM 2. CODE OF ETHICS"

ITEM 2. CODE OF ETHICS.

Not applicable.

link2 "ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT"

ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT.

Not applicable.

link2 "ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES"

ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES.

Not applicable.

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PAGEBREAK

link2 "ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS"

ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS.

Not applicable.

link2 "ITEM 6. SCHEDULE OF INVESTMENTS"

ITEM 6. SCHEDULE OF INVESTMENTS

Included in the Report to Shareholders in Item 1.

link2 "ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES"

ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

Not applicable.

link2 "ITEM 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES"

ITEM 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

Not applicable.

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PAGEBREAK

link2 "ITEM 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS"

ITEM 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS.

Not applicable

link2 "ITEM 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS"

ITEM 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

No material changes.

link2 "ITEM 11. CONTROLS AND PROCEDURES"

ITEM 11. CONTROLS AND PROCEDURES.

a) The registrant’s principal executive officer and principal financial officer have evaluated the registrant’s disclosure controls and procedures within 90 days of this filing and have concluded that the registrant’s disclosure controls and procedures were effective, as of that date, in ensuring that information required to be disclosed by the registrant in this Form N-CSR was recorded, processed, summarized, and reported timely.

b) There were no changes in the registrant’s internal controls over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) that occurred during the second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

link2 "ITEM 12. EXHIBITS"

ITEM 12. EXHIBITS.

(a)(1) Code of Ethics — Not applicable.

(a)(2)(i) Certification of Principal Executive Officer.

(a)(2)(ii) Certification of Principal Financial Officer.

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PAGEBREAK

link1 " SIGNATURES"

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Calamos Convertible Opportunities and Income Fund

By: /s/ John P. Calamos, Sr.
Name: John P. Calamos, Sr.
Title: Principal Executive Officer
Date: June 24, 2011
By: /s/ Nimish S. Bhatt
Name: Nimish S. Bhatt
Title: Principal Financial Officer
Date: June 24, 2011

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By: /s/ John P. Calamos, Sr.
Name: John P. Calamos, Sr.
Title: Principal Executive Officer
Date: June 24, 2011
By: /s/ Nimish S. Bhatt
Name: Nimish S. Bhatt
Title: Principal Financial Officer
Date: June 24, 2011

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