------------------------------
                               UNITED STATES                                OMB APPROVAL
                    SECURITIES AND EXCHANGE COMMISSION             ------------------------------
                          Washington, D.C. 20549                   OMB Number 3235-0145
                                                                   ------------------------------
                                                                   Expires:   January 31, 2006
                                                                   ------------------------------
                                                                   Estimated average burden
                                                                   hours per response . . . 11


                              INITIAL SCHEDULE 13G


                    Under the Securities Exchange Act of 1934


                             Petroquest Energy, Inc.
-------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
-------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    716748108
-------------------------------------------------------------------------------
                                 (CUSIP Number)

                                December 31, 2005
-------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

        |x|       Rule 13d-1(b)

                  Rule 13d-1(c)

                  Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in 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).








                                PAGE 1 OF 9 PAGES





----------------------                                    ---------------------
CUSIP No. 716748108                 13G                   Page  2  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           Manulife Financial Corporation

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada

-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiaries, MFC
           Global Investment Management (U.S.A.) Limited, John Hancock Advisers,
           LLC and Independence Investments, LLC
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9 above.
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           HC
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 2 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No. 716748108                 13G                   Page  3  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           MFC Global Investment Management (U.S.A.) Limited

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada

-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              14,495
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             14,495
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           14,495
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           .03%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 3 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No. 716748108                 13G                   Page  4  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           Independence Investments, LLC

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             3,074,900
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 3,074,900
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           3,074,900
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           6.5%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 4 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No. 71674810                  13G                   Page  5  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Advisers, LLC

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             487,600
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             487,600
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           487,600
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           1.0%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 5 OF 9 PAGES



Attention:  Intentional  misstatements  or omissions of fact constitute  Federal
            criminal violations (See 18 U.S.C. 1001)

   Item 1(a)    Name of Issuer:
                ---------------
                Petroquest Energy, Inc.

   Item 1(b)    Address of Issuer's Principal Executive Offices:
                ------------------------------------------------
                400 E. Kaliste Saloom Rod., Suite 6000
                Lafayette, Louisiana 70508

   Item 2(a)    Name of Person Filing:
                ----------------------
                This filing is made on behalf of Manulife Financial  Corporation
                ("MFC"),  and  MFC's  indirect,  wholly-owned  subsidiaries  MFC
                Global  Investment  Management  (U.S.A.) Limited ("MFC Global"),
                Independence Investments,  LLC ("IIA") and John Hancock Advisers
                LLC ("JHA").

   Item 2(b)    Address of the Principal Offices:
                ---------------------------------
                The principal  business  office of MFC and MFC Global is located
                at 200 Bloor Street,  East, Toronto,  Ontario,  Canada, M4W 1E5;
                IIA is located at 53 State Street,  Boston,  MA 02109 and JHA is
                located at 601 Congress Street, Boston, Massachusetts 02210.

   Item 2(c)    Citizenship:
                ------------
                MFC and MFC Global  are  organized  and exist  under the laws of
                Canada.  IIA and JHA are  organized  and exist under the laws of
                the State of Delaware.

   Item 2(d)    Title of Class of Securities:
                -----------------------------
                Common Stock

   Item 2(e)    CUSIP Number:
                -------------
                716748108

   Item 3       If the Statement is being filed pursuant to Rule 13d-1(b),
                or 13d-2(b), check whether the person filing is a:

                MFC:        (g) (X) Parent Holding Company, in accordance
                                    with ss.240.13d-1(b)(ii)(G).

                MFC Global: (e) (X) Investment Adviser registered under
                                    ss.203 of the Investment Advisers Act
                                    of 1940.

                IIA:        (e) (X) Investment Adviser registered under
                                    ss.203 of the Investment Advisers Act
                                    of 1940.

                JHA:        (e) (X) Investment Adviser registered under
                                    ss.203 of the Investment Advisers Act
                                    of 1940.

   Item 4       Ownership:
                ----------

                (a) Amount   Beneficially   Owned:  MFC  Global  has  beneficial
                    ownership  of  14,495  shares  of  Common  Stock,   IIA  has
                    beneficial ownership of 3,074,900 shares of Common Stock and
                    JHA has  beneficial  ownership  of 487,600  shares of Common
                    Stock.  Through its  parent-subsidiary  relationship  to MFC
                    Global,  IIA and JHA,  MFC may be deemed to have  beneficial
                    ownership of all of the shares held by these entities.


                                PAGE 6 OF 9 PAGES



                (b) Percent of Class:
                    Of the 47,293,490 shares  outstanding as of October 25, 2005
                    according to the issuer's  quarterly report on form 10-Q for
                    the period ended  September 30, 2005,  MFC Global held .03%,
                    IIA held 6.5% and JHA held 1%.

                (c) Number of shares as to which the person has:

                    (i) sole power to vote or to direct the vote:
                        IIA and JHA each has sole power to vote or to direct the
                        voting of the shares of Common Stock  beneficially owned
                        by each of them.

                   (ii) shared power to vote or to direct the vote:
                        MFC  Global  has  shared  power to vote or to direct the
                        voting of the shares it beneficially owns.

                  (iii) sole power to dispose or to direct the disposition of:
                        IIA  has  sole   power  to  dispose  or  to  direct  the
                        disposition   of  the   shares   of   Common   Stock  it
                        beneficially owns.

                   (iv) shared power to dispose or to direct the disposition of:
                        MFC Global  and JHA each has shared  power to dispose or
                        to direct the  disposition  of the  shares  beneficially
                        owned by each of them.


   Item 5       Ownership of Five Percent or Less of a Class:
                ---------------------------------------------
                Not applicable.

   Item 6       Ownership of More than Five Percent on Behalf of Another Person:
                ----------------------------------------------------------------
                Not applicable.

   Item 7       Identification and Classification of the Subsidiary which
                Acquired the Security Being Reported on by the Parent
                Holding Company:
                ---------------------------------------------------------
                See Items 3 and 4 above.

   Item 8       Identification and Classification of Members of the Group:
                ----------------------------------------------------------
                Not applicable.

   Item 9       Notice of Dissolution of a Group:
                ---------------------------------
                Not applicable.

   Item 10      Certification:
                --------------
                By signing below the undersigned  certifies that, to the best of
                its knowledge and belief, the securities  referred to above were
                acquired  and are held in the  ordinary  course of business  and
                were not  acquired  and are not held for the  purpose of or with
                the effect of changing or influencing  the control of the issuer
                of the  securities  and  were not  acquired  and are not held in
                connection  with or as a participant in any  transaction  having
                that purpose or effect.

                                PAGE 7 OF 9 PAGES




                                    SIGNATURE

     After reasonable inquiry and to the best of its knowledge and belief,  each
of the undersigned certifies that the information set forth in this statement is
true, complete and correct.

                               Manulife Financial Corporation

                               By:      /s/ Angela Shaffer
                                        ----------------------
                                        Name:   Angela Shaffer
                                        Title:  Vice President and
Dated:  February 8, 2006                        Corporate Secretary


                               MFC Global Investment Management (U.S.A.) Limited

                               By:      /s/ Gordon Pansegrau
                                        --------------------
                                        Name:   Gordon Pansegrau
                                        Title:  General Counsel, Secretary and
Dated:  February 8, 2006                        Chief Compliance Officer


                               Independence Investments, LLC

                               By:      /s/ Patricia Thompson
                                        ---------------------
                                        Name:   Patricia Thompson
Dated:  February 8, 2006                Title:  Chief Compliance Officer


                               John Hancock Advisers, LLC

                               By:      /s/Al Ouellette
                                        ---------------
                                        Name:   Al Ouellette
                                        Title:  Assistant Vice President and
Dated:  February 8, 2006                        Senior Counsel




                                PAGE 8 OF 9 PAGES




EXHIBIT A

                             JOINT FILING AGREEMENT
                             ----------------------

      Manulife Financial Corporation,  MFC Global Investment Management (U.S.A.)
Limited, Independence Investments, LLC and John Hancock Advisers, LLC agree that
the Initial  Schedule 13G to which this  Agreement is attached,  relating to the
Common Stock of Petroquest Energys, Inc. is filed on behalf of each of them.


                               Manulife Financial Corporation

                               By:      /s/ Angela Shaffer
                                        ----------------------
                                        Name:   Angela Shaffer
                                        Title:  Vice President and
Dated:  February 8, 2006                        Corporate Secretary


                               MFC Global Investment Management (U.S.A.) Limited

                               By:      /s/ Gordon Pansegrau
                                        --------------------
                                        Name:   Gordon Pansegrau
                                        Title:  General Counsel, Secretary and
Dated:  February 8, 2006                        Chief Compliance Officer


                               Independence Investments, LLC

                               By:      /s/ Patricia Thompson
                                        ------------------
                                        Name:   Patricia Thompson
Dated:  February 8, 2006                Title:  Chief Compliance Officer


                               John Hancock Advisers, LLC

                               By:      /s/Al Ouellette
                                        ---------------
                                        Name:   Al Ouellette
                                        Title:  Assistant Vice President and
Dated:  February 8, 2006                        Senior Counsel




                                PAGE 9 OF 9 PAGES