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                                         Filed by Bellwether Exploration Company
                           Pursuant to Rule 425 under the Securities Act of 1933

                                           Subject Company: Bargo Energy Company
                                                              File No. 333-54798




                         BELLWETHER EXPLORATION COMPANY
                             1331 LAMAR, SUITE 1455
                            HOUSTON, TEXAS 77010-3039
                                 (713) 495-3000



To the Stockholders of Bellwether Exploration Company:

         On April 26, 2001, we mailed a joint proxy/prospectus/annual report
soliciting your proxy to vote on the matters to be acted upon at our annual
meeting of stockholders, including our proposed merger with Bargo Energy
Company. The proxy card enclosed with these materials contained a printing
error, incorrectly stating that the date of the meeting is May 11, 2001 instead
of May 16, 2001.

         Bellwether will accept the proxy card with the incorrect date at the
annual meeting for purposes of voting your shares. Therefore, if you have
already mailed your proxy card there is no need for you to take further action
for your shares to be voted as provided on the proxy card. We have enclosed a
proxy card with the correct date for your use if you have not yet voted.

         If you require any assistance to vote, please call MacKenzie Partners,
Inc. at 1-800-322-2885 or Lance Weaver at (713) 495-3000.

                                                     Yours truly,

                                                     /s/ ROLAND E. SLEDGE

                                                     Roland E. Sledge
                                                     General Counsel
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INVESTOR NOTICE

         Investors and security holders are urged to read the joint proxy
statement/prospectus/annual report included in the Registration Statement on
Form S-4 filed with the SEC in connection with the proposed merger because it
contains important information. Bellwether and Bargo have filed the joint proxy
statement/prospectus/annual report with the SEC. Investors and security holders
may obtain a free copy of the joint proxy statement/prospectus/annual report and
other documents filed by Bellwether and Bargo with the SEC at the SEC's web site
at www.sec.gov. The joint proxy statement/prospectus/annual report and such
other documents (relating to Bellwether) may also be obtained for free from
Bellwether by directing such request to: Bellwether Exploration Company, 1331
Lamar, Suite 1455, Houston, Texas 77010, Attention: Lance Weaver; telephone:
(713) 495-3061; e-mail: weaverl@bellwetherexp.com. The joint proxy
statement/prospectus/annual report and such other documents (relating to Bargo)
may also be obtained for free from Bargo by directing such request to: Bargo
Energy Company, 700 Louisiana, Suite 3700, Houston, Texas 77002, Attention:
Jerry Sears; telephone: (713) 236-9792; e-mail: jsears@bargo.com.

         Bellwether, its directors, executive officers and certain members of
management and employees may be considered "participants in the solicitation" of
proxies from Bellwether's stockholders in connection with the merger.
Information regarding such persons and a description of their interests in the
merger is contained in the Registration Statement on Form S-4.

         Bargo, its directors, executive officers and certain members of
management and employees may be considered "participants in the solicitation" in
connection with the merger. Information regarding such persons and a description
of their interests in the merger is contained in the Registration Statement on
Form S-4.

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