UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 4)*

Gulf Island Fabrication, Inc.

(Name of Issuer)

Common Stock, no par value per share

(Title of Class of Securities)

402307 10 2

(CUSIP Number)

Alden J. Laborde

400 Poydras Street, Suite 1560

New Orleans, Louisiana 70130

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

October 14, 2005

(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 that 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  ¨.

Note:  Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

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CUSIP No. [402307 10 2]

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CUSIP No. [402307 10 2]

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The purpose of this amendment is to reflect in Item 5

(1) recent sales of shares of Common Stock, of which Alden J. Laborde is a beneficial owner, representing more than 1% of the outstanding shares of Common Stock of the Issuer, by Almar Foundation, a charitable Louisiana trust, pursuant to a Rule 10b5-1 Plan; and

(2) recent sales of shares of Common Stock by certain Members and their family members.

Item 5. Interest in Securities of the Issuer.

The amended Item 5 shall read as follows:

(a), (b), and (d) As of the date hereof, Alden J. Laborde is the beneficial owner of 1,129,000 shares of Common Stock, which is approximately 9.32% of the outstanding shares of Common Stock. Alden J. Laborde has the sole power to vote or to direct the vote and the sole power to dispose or to direct the disposition of 9,300 of such shares and shares the power to vote or to direct the vote and shares the power to dispose or to direct the disposition of 1,119,700 of such shares. Of such 1,119,700 shares as to which Alden J. Laborde shares voting and investment power, 924,700 are held directly by the LLC, 20,000 are held directly by All Aboard and 175,000 are held directly by the Almar Foundation, a charitable Louisiana trust. Alden J. Laborde shares voting and investment power with the other Members of the LLC over the 924,700 shares of Common Stock held by the LLC, which is approximately 7.55% of the outstanding shares of Common Stock, he shares voting and investment power with the other directors of All Aboard over the 20,000 shares of Common Stock held by All Aboard and he shares voting and investment power with the other trustees of the Almar Foundation over the 175,000 shares of Common Stock held by the Almar Foundation, which is approximately 1.42% of the outstanding shares of Common Stock. Each Member of the LLC is also a trustee of the Almar Foundation. The LLC, All Aboard and the Almar Foundation have the right to receive and the power to direct the receipt of dividends from, and the proceeds from the sale of, the shares of Common Stock held directly by them, respectively.

The answer to Item 2 of this Schedule 13D is incorporated by reference in partial response to this Item 5(a), (b), and (d).

Set forth below with respect to each of the Members other than Alden J. Laborde is such person’s name, the total number of shares of Common Stock beneficially owned by such Member as of the date hereof, the number of such shares as to which such Member has sole voting and dispositive power, and the number of such shares as to which such Member has shared voting and dispositive power. Each such Member beneficially owns less than 5% of the outstanding shares of Common Stock. For purposes of the response to this Item 5(a), (b), and (d), beneficial ownership is determined in accordance with Rule 13d-3 of the Securities and Exchange Commission based on information furnished by each such Member.

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(c) No Reporting Person or Member has engaged in any transactions involving Common Stock during the past sixty days not previously reported on this Schedule 13G, except the following:

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Sales by Susan Laborde Couvillon and family members:

Sales by Stephanie B. Laborde

Sales by Jane Laborde Roussel and family members:

(e) Not applicable.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct as of November 11, 2005.