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                                                                    EXHIBIT 10.5

                                                                        Hackett

                                VOTING AGREEMENT

         VOTING AGREEMENT ("Agreement") dated as of November 24, 1998 between
Ocean Energy, Inc., a Delaware corporation ("OEI"), and James T. Hackett (the
"Stockholder").

                              W I T N E S S E T H:

         WHEREAS, as of the date hereof the Stockholder owns an aggregate of
131,000 shares (together with any shares acquired after the date hereof, the
"Shares") of Common Stock, par value $.10 per share ("Seagull Common Stock"), of
Seagull Energy Corporation, a Texas corporation (the "Seagull").

         WHEREAS, OEI is prepared to enter into an Agreement and Plan of Merger
with Seagull (as amended from time to time, the "Merger Agreement") providing
for the merger of OEI with and into Seagull (the "Merger") with Seagull being
the surviving entity;

         WHEREAS, in order to encourage OEI to enter into the Merger Agreement
with Seagull, the Stockholder is willing to enter into certain arrangements with
respect to the Shares;

         NOW, THEREFORE, in consideration of the premises set forth above, the
mutual promises set forth below, and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

         1. Stockholder's Support of the Merger. From the date hereof until the
earliest to occur of (i) the termination of the Merger Agreement, and (ii) the
consummation of the Merger:

                  (a) The Stockholder beneficially owns the Shares and will not,
         directly or indirectly, (i) sell, transfer, pledge or otherwise dispose
         of any Shares to any person other than OEI or its designee unless such
         person shall have agreed in writing to be bound by the terms of this
         Agreement, or (ii) grant a proxy with respect to any Shares to any
         person other than OEI or its designee, or grant an option with respect
         to any of the foregoing, or enter into any other agreement or
         arrangement with respect to any of the foregoing.

                  (b) The Stockholder will not initiate, solicit or encourage
         (including by way of furnishing information or assistance), or take any
         other action to facilitate, any inquiries or the making of any proposal
         relating to, or that may reasonably be expected to lead to, any merger,
         consolidation, share exchange, business combination or similar
         transaction involving Seagull or any of its subsidiaries or the
         acquisition in any manner, directly or indirectly, of a material equity
         interest in any voting securities of, or a substantial portion of the
         assets of, Seagull or any of its Subsidiaries, other than the
         transactions contemplated by this Agreement or the Merger Agreement (a
         "Competing Transaction"), or enter into discussions


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         or negotiate with any person or entity in furtherance of such inquiries
         or to obtain a Competing Transaction, or agree to, or endorse, any
         Competing Transaction, or authorize or permit any investment banker,
         financial advisor, attorney, accountant or other representative
         retained by the Stockholder to take any such action. The Stockholder
         shall promptly notify OEI of all relevant terms of any such inquiries
         or proposals received by the Stockholder or by any such investment
         banker, financial advisor, attorney, accountant or other representative
         relating to any of such matters and if such inquiry or proposal is in
         writing, the Stockholder shall deliver or cause to be delivered to OEI
         a copy of such inquiry or proposal.

                  (c) The Stockholder agrees that it will vote all Shares (i) in
         favor of approval of the Merger Agreement and the Merger and the
         election of directors contemplated by the Merger Agreement and (ii)
         subject to the provisions of paragraph (d) below, against any
         combination proposal or other matter that may interfere or be
         inconsistent with the Merger (including without limitation a Competing
         Transaction).

                  (d) The Stockholder agrees that, if requested by OEI, the
         Stockholder will not attend and the Stockholder will not vote the
         Shares at any annual or special meeting of stockholders at which a
         Competing Transaction is being considered, or execute any written
         consent of stockholders relating directly or indirectly to a Competing
         Transaction, during such period.

                  (e) The Stockholder acknowledges that the terms of this
         Agreement will be required to be described, and this Agreement will be
         required to be filed, in certain securities law filings relating to the
         Merger.

                  (f) To the extent inconsistent with the provisions of this
         Section 1, the Stockholder hereby revokes any and all proxies with
         respect to the Shares or any other voting securities of Seagull held by
         the Stockholder.

         Notwithstanding anything to the contrary set forth herein, this
Agreement shall not restrict the Stockholder from acting in accordance with his
fiduciary duties as an officer or director of Seagull.

         2.       Miscellaneous

                  (a) The Stockholder, on the one hand, and OEI, on the other,
         acknowledge and agree that irreparable damage would occur if any of the
         provisions of this Agreement were not performed in accordance with
         their specific terms or were otherwise breached. It is accordingly
         agreed that the parties shall be entitled to an injunction or
         injunctions to prevent breaches of the provisions of this Agreement and
         to enforce specifically the terms and provisions hereof in any court of
         the United States or any state thereof having jurisdiction, in addition
         to any other stockholder to which they may be entitled at law or
         equity.


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                  (b) Descriptive headings are for convenience only and shall
         not control or affect the meaning or construction of any provision of
         this Agreement.

                  (c) All notices, consents, requests, instructions, approvals
         and other communications provided for herein shall be validly given,
         made or served, if in writing and delivered personally, by telecopy or
         sent by registered mail, postage prepaid:

                  If to OEI:

                           Ocean Energy, Inc.
                           1201 Louisiana, Suite 1400
                           Houston, Texas  77002
                           Attention: Robert K. Reeves
                           Facsimile No.:  (713) 420-1182

                           With copies to:

                           Akin, Gump, Strauss, Hauer & Feld, L.L.P.
                           1700 Pacific Avenue, Suite 4100
                           Dallas, Texas 75201-4675
                           Attention: Michael E. Dillard, P.C.
                           Facsimile No.:  (214) 969-4343

                           Seagull Energy Corporation
                           1001 Fannin, Suite 1700
                           Houston, Texas  77002
                           Attention: General Counsel
                           Facsimile No.:  (713) 210-2194

                           Vinson & Elkins L.L.P.
                           2300 First City Tower
                           1001 Fannin
                           Houston, Texas  77002-6760
                           Attention:  J. Mark Metts
                           Facsimile No.:  (713) 615-5605


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                  If to the Stockholder:

                           James T. Hackett
                           c/o Seagull Energy Corporation
                           1001 Fannin, Suite 1700
                           Houston, Texas 77002
                           Facsimile No.:  713-951-4790

         or to such other address or telecopy number as any party may, from time
         to time, designate in a written notice given in a like manner. Notice
         given by telecopy shall be deemed delivered on the day the sender
         receives telecopy confirmation that such notice was received at the
         telecopy number of the addressee. Notice given by mail as set out above
         shall be deemed delivered three days after the date the same is
         postmarked.

                  (d) From and after the termination of this Agreement, the
         covenants of the parties set forth herein shall be of no further force
         or effect and the parties shall be under no further obligation with
         respect thereto.

                  (e) Definitions. For purposes of this Agreement, the following
         terms shall have the following meanings:

                           (i) Affiliate. "Affiliate" shall have the meaning
                  ascribed to it in Rule 12b-2 of the General Rules and
                  Regulations under the Exchange Act, as in effect on the date
                  hereof.

                           (ii) Merger. "Merger" shall mean the transaction
                  referred to in the second whereas clause of this Agreement, or
                  any amendment to or modification that does not adversely
                  affect the economic value of the Merger to the Stockholder
                  pursuant to the transaction set forth in the Merger Agreement.

                           (iii) Person. A "person" shall mean any individual,
                  firm, corporation, partnership, trust, limited liability
                  company or other entity.

                  (f) Due Authorization; No Conflicts. The Stockholder hereby
         represents and warrants to OEI as follows: the Stockholder has full
         power and authority to enter into this Agreement. Neither the execution
         or delivery of this Agreement nor the consummation of the transactions
         contemplated herein will (a) conflict with or result in a breach,
         default or violation of any agreement, proxy, document, instrument,
         judgment, decree, order, governmental permit, certificate, license,
         law, statute, rule or regulation to which the Stockholder is a party or
         to which it is subject, (b) result in the creation of any lien, charge
         or other encumbrance on any Shares or (c) require the Stockholder to
         obtain the consent of any private nongovernmental third party. No
         consent, action, approval or authorization of, or registration,
         declaration or filing with, any governmental department, commission,
         agency

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         or other instrumentality or any other person or entity is required to
         authorize, or is otherwise required in connection with, the execution
         and delivery of this Agreement or the Stockholder's performance of the
         terms of this Agreement or the validity or enforceability of this
         Agreement.

                  (g) Successors and Assigns. This Agreement shall be binding
         upon, and inure to the benefit of, the parties hereto and their
         respective heirs, personal representatives, successors and assigns,
         but, except as contemplated pursuant to paragraph 1(a), shall not be
         assignable by any party hereto without the prior written consent of the
         other parties hereto.

                  (h) Waiver. No party may waive any of the terms or conditions
         of this Agreement except by a duly signed writing referring to the
         specific provision to be waived.

                  (i) Governing Law. This Agreement shall be governed by, and
         construed and enforced in accordance with, the laws of the State of
         Texas.

                  (j) Entire Agreement. This Agreement constitutes the entire
         agreement, and supersedes all other and prior agreements and
         understandings, both written and oral, among the parties hereto and
         their Affiliates.

                  (k) Counterparts. This Agreement may be executed in two or
         more counterparts, each of which shall be deemed an original but all of
         which shall constitute one and the same instrument.

                  (l) Effectiveness. This Agreement shall not become effective
         until Seagull has amended the Seagull Rights Plan (as defined in the
         Merger Agreement) to provide that OEI will not become an "Acquiring
         Person" thereunder as a result of its entering into this Agreement and
         the other Voting Agreements to be entered into by OEI in connection
         with the Merger.


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         IN WITNESS WHEREOF, the Stockholder and OEI have each caused this
Agreement to be duly executed as of the day and year first above written.

                                 OCEAN ENERGY, INC.


                                 By: /s/ JAMES C. FLORES
                                    ---------------------------------------
                                      James C. Flores
                                      President and Chief Executive Officer


                                 JAMES T. HACKETT

                                 /s/ JAMES T. HACKETT
                                 ------------------------------------------











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