Omega Protein Corporation (OME) Is A Good Buy At $17 Says Hedge Fund Manager

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

(Amendment No. 4)

Under the Securities Exchange Act of 1934

OMEGA PROTEIN CORPORATION 

 (Name of Issuer)

Common Stock, $0.01 par value

 (Title of Class of Securities)

68210P107

( CUSIP Number)

Wynnefield Partners Small Cap Value,
L.P. I

450 Seventh Avenue, Suite 509

New York, New York 10123

Attention: Mr. Nelson Obus

Copy to:

Jeffrey S. Tullman, Esq.

Kane Kessler, P.C.

1350 Avenue of the Americas, 26^th
Floor

New York, New York 10019

(212) 541-6222

(Name, Address and Telephone
Number of Person Authorized to Receive Notices and Communications)

March
28, 2016 

 (Date of Event which requires Filing
of this Statement)

If the filing person has previously filed
a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because
of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ¨

Item 1. Security and Issuer.

This Amendment No. 4 amends
the Statement of Beneficial Ownership on Schedule 13D originally filed with the Securities and Exchange Commission
(the “Commission”) on August 11, 2015 and as amended by Amendment No. 1, filed on October 8, 2015, as amended
by Amendment No. 2, filed on November 17, 2015, and as further amended by Amendment No. 3, filed on March 1, 2016
(collectively, the “Schedule 13D”) by the Wynnefield Reporting Persons (as defined in the Schedule 13D) with
respect to shares of common stock, $0.01 par value per share (the “Common Stock”) of Omega Protein Corporation, a
Nevada corporation (the “Issuer”). The Issuer maintains its principal executive office at 2105 City West Blvd.,
Suite 500, Houston, Texas 77042. Unless specifically amended hereby, the disclosures set forth in the Schedule 13D shall
remain unchanged. Capitalized terms used but not otherwise defined herein shall have the meanings set forth in the Schedule
13D.

Item 3. Source and Amount of Funds or
Other Consideration.

Item 3 of the Schedule 13D is hereby amended and restated
as follows:

The securities reported in this Schedule
13D/A as directly beneficially owned by the Wynnefield Reporting Persons were acquired with funds of approximately $20,872,731 (including
brokerage commissions). All such funds were provided from the working capital or personal funds of the Wynnefield Reporting Persons
who directly beneficially own such securities.

Item 4. Purpose of the Transaction

Item 4 of the Schedule 13D is hereby amended by the addition
of the following:

This Amendment No. 4 to Schedule 13D is being filed to
disclose that the Wynnefield Reporting Persons have increased their beneficial ownership in the Issuer’s Common
Stock due to the Wynnefield Reporting Persons’ belief that the Issuer’s Common Stock is currently undervalued.

Item 5. Interest in Securities of the Issuer.

Item
5 of the Schedule 13D is hereby amended and restated as follows:

(a), (b) and (c) As of March 28, 2016, the Wynnefield Reporting Persons beneficially owned in the
aggregate 1,713,051 shares of Common Stock, constituting approximately 7.7% of the outstanding shares of Common Stock. The
percentage of shares of Common Stock reported as being beneficially owned by the Wynnefield Reporting Persons is based upon
22,204,451 shares outstanding as of February 29, 2016, as set forth in the Issuer’s Annual Report on Form 10-K for
the fiscal year ended December 31, 2015, filed with the Commission on March 9, 2016.

The following table
sets forth certain information with respect to shares of Common Stock directly beneficially owned by the Wynnefield Reporting Persons
listed below:

WCM is the sole general
partner of Wynnefield Partners and Wynnefield Partners I and, accordingly, may be deemed to be the indirect beneficial owner (as
that term is defined under Rule 13d-3 under the Exchange Act) of the Common Stock that Wynnefield Partners and Wynnefield Partners
I beneficially own. WCM, as the sole general partner of Wynnefield Partners and Wynnefield Partners I, has the sole power to direct
the voting and disposition of the Common Stock that Wynnefield Partners and Wynnefield Partners I beneficially own. Messrs. Obus
and Landes are the co-managing members of WCM and, accordingly, each of Messrs. Obus and Landes may be deemed to be the indirect
beneficial owner (as that term is defined under Rule 13d-3 under the Exchange Act) of the Common Stock that WCM may be deemed to
beneficially own. Each of Messrs. Obus and Landes, as co-managing members of WCM, share the power to direct the voting and disposition
of the shares of Common Stock that WCM may be deemed to beneficially own.

WCI is the sole investment
manager of Wynnefield Offshore and, accordingly, may be deemed to be the indirect beneficial owner (as that term is defined under
Rule 13d-3 under the Exchange Act) of the Common Stock that Wynnefield Offshore beneficially owns. WCI, as the sole investment
manager of Wynnefield Offshore, has the sole power to direct the voting and disposition of the Common Stock that Wynnefield Offshore
beneficially owns. Messrs. Obus and Landes are executive officers of WCI and, accordingly, each may be deemed to be the indirect
beneficial owner (as that term is defined under Rule 13d-3 under the Exchange Act) of the Common Stock that WCI may be deemed to
beneficially own. Messrs. Obus and Landes, as executive officers of WCI, share the power to direct the voting and disposition of
the shares of Common Stock that WCI may be deemed to beneficially own.

The Plan is an employee
profit sharing plan. Messrs. Obus and Landes are the co-trustees of the Plan and accordingly, Messrs. Obus and Landes
may be deemed to be the indirect beneficial owner (as that term is defined under Rule 13d-3 under the Exchange Act) of the shares
of Common Stock that the Plan may be deemed to beneficially own. Each of Messrs. Obus and Landes, as the trustees
of the Plan, shares with the other the power to direct the voting and disposition of the shares of Common Stock beneficially owned
by the Plan.

Beneficial ownership of the Common Stock shown on the cover pages of and set
forth elsewhere in this Schedule 13D for each member of the Wynnefield Reporting Persons assumes that they have not formed a
group for purposes of Section 13(d)(3) under the Exchange Act, and Rule 13d-5(b)(1) promulgated thereunder. If the members of
the Wynnefield Reporting Persons were deemed to have formed a group for purposes of Section 13(d)(3) and Rule 13d-5(b)(1),
the group would be deemed to own beneficially (and may be deemed to have shared voting and dispositive power over) in the
aggregate 1,713,051 shares of Common Stock, constituting approximately 7.7% of the outstanding shares of Common Stock. The
percentage of shares of Common Stock reported as being beneficially owned by the Wynnefield Reporting Persons is based upon
22,204,451 shares outstanding as of February 29, 2016, as set forth in the Issuer’s Annual Report on Form 10-K for the
fiscal year ended December 31, 2015, filed with the Commission on March 9, 2016.

The filing of this
Schedule 13D and any future amendment by the Wynnefield Reporting Persons, and the inclusion of information herein and therein
with respect to WCM, WCI and Messrs. Obus and Landes, shall not be considered an admission that any of such persons, for the purpose
of Section 16(b) of the Exchange Act, are the beneficial owners of any shares in which such persons do not have a pecuniary interest.
Each of WCM, WCI and Messrs. Obus and Landes disclaims any beneficial ownership of the shares covered by this Schedule 13D.

The Wynnefield Reporting Persons
have acquired or sold shares of Common Stock since the filing of Amendment No. 3 to Schedule 13D with the Commission on March
1, 2016 as follows:

(d) and (e). Not Applicable.

SIGNATURE

After reasonable inquiry and to the best
of their knowledge and belief, the undersigned certify that the information set forth in this Schedule 13D is true, complete and
correct.