W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 1985 A bioeconomic model of the middle Atlantic surf clam (Spisula solidissima) fishery Thomas M. Armitage College of William and Mary - Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Fresh Water Studies Commons, Marine Biology Commons, and the Oceanography Commons Recommended Citation Armitage, Thomas M., "A bioeconomic model of the middle Atlantic surf clam (Spisula solidissima) fishery" (1985). Dissertations, Theses, and Masters Projects. Paper 1539616551. https://dx.doi.org/doi:10.25773/v5-a3d5-we79 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a manuscript sent to us for publication and microfilming. While the most advanced technology has been used to pho- tograph and reproduce this manuscript, the quality of the reproduction Is heavily dependent upon the quality of the material submitted. Pages in any manuscript may have Indistinct print. In all cases the best available copy has been filmed. The following explanation of techniques is provided to help clarify notations which may appear on this reproduction. I. Manuscripts may not always be complete. When it is not possible to obtain missing pages, a note appears to Indicate this. 2 When copyrighted materials are removed from the manuscript, a note ap­ pears to Indicate this. 3. Oversite materials (mops, drawings, and charts) are photographed by sec­ tioning the original, beginning at the upper left hand comer and continu­ ing from left to right In equal sections with small overlaps. Bach oversize page Is also filmed as one exposure and Is available, for an additional charge, as a standard 35mm slide or in black and white paper format.* 4. Most photographs reproduce acceptably on positive microfilm or micro­ fiche but lack clarity on xerographic copies made from the microfilm. For an additional charge, all photographs are available in black and white standard 35mm slide format.* *|br more information about black and white slides or enlarged paper reproductions, please contact the Dissertations Customer Services Department "U nharafy Mkroflhm _ ififrrmdiiwuil 6604205 Aimllagi, Thom ti Marshall A BIOECONOMIC MODEL OF THE MIDDLE ATLANTIC SURF CUM (SPISULA SOLIDISSIMA) FISHERY The of William and Mary in Virginia Ph.O. 1985 University Microfilms International 300 N. Ze«b Road, Ann Artur. Ml 46106 Copyright 1986 by Armitage, Thomas Marshall All Rights Reserved PLEASE NOTE; In ftM cue* this material has b u n filmed in the beat possible way from the available copy. Problems encountered with this document have been identified here with a check mark __ i. Glossy photographs or page*. 2. Colored Illustrations, paper or prl nt ______ 3. Photographs with dark background _____ 4. Illustrations are poor copy_______ 5. Pages with black marks, not original copy „ 6. Print shows through u there is text on both sides of page, 7. Indistinct, broken or small print on several paces B. Print exceeds margin requirem ents ______ 9. Tightly bound copy with print lost in spine _______ 10. Computer printout pages with indistinct print 11. Psgats) lacking when material received, and not available from school or author, 12. Psgets)____________ seem to be missing In numbering only as text follows. 13. Two pages numbered . Text follows. 14. Curling and wrinkled pages _______ 15. Dissertation contains pages with prim at a slant, filmed as received __________ 16. Other __________ _________________ _ ____________________________________ University Microfilms International i 3IOECOHOHIC MODEL OF THE MIDDLE ATLANTIC SURF CLAM <3PISULA SOLI PI SSI HA) FISHERY A Dissertation Presented to The Faculty of the School of Marine Science The College of William and Mary in Virginia In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy by Thornes Marshall Armitage 1 985 APPROVAL SHEET This dissertation L> submitted in partial fulfillment of the requirement* for tha degree oT Doctor of Philosophy Thomas N. Armitsge Approved, December 1965 Herbert M. Austi n. Ph. D. ( Chai rman) m/B ar tie tt Thebarga, LL. H. Jr. - Ph. D. Hi 111am D. DuPaul, Ph. D. Robert J. Byrhe, Ph. D. J2ja Ivar B, Strand, Ph. D. University of Maryland <S>1S60 THOMAS MARSHALL ARMITAGE All Mights Rawrved TABLB OF C0MT6HT3 Page fable of Contents. .......................... , r . , . ............................................i i i icknowl edgements. ........................., . , . ......................................... v List of Tables. ..................................... vi List of Figures. .............................................................................................vi i A bstract ...................................................................................................................v iii Chapter I. Introduction and Hypothesis - Objective of the Study ......................................................................................... 2 Chapter II. Methods - The Surf Clam Fishery as a Bioeconomic System ........................................................................ 8 Concept of the Fishery Simulation Model.... 8 Harvesting and Processing Sectors ........................... 13 Life History and Population Dynamics .................. 16 Chapter III. Methods - Demand Analysis. .................. 39 Variables in the Price Equation............ 39 Mechanism of Price Formation. .................. 47 Market Area. .......................................................... 49 Statistical Estimation Procedure. ..................... 51 Results of Demand Analysis. ....................................... - - 54 Discussion. .............................................................................. 61 Problems and Future Research Heeds.. .................. 64 Chapter IV. Methods - Cost Analysis. .......................................... 68 Sources of Fishing Sector Data. ................. 69 Identification and Quantification of Pishing Costs ............................. 70 Sources of Processing Sector Data. ............... 90 Identification and Quantification or Processing Costs ...................................................................... 91 Processing Plant Charactariat 1csr r . r .................. 95 Production Capacity and drouth Potential. 102 Chapter V. Methods - Model Construction ..............................................107 A Unique Modeling Approach ..................................................107 Model s tr u c tu r e ...................................................................................110 Chapter 1/1. Results - Ceee Studies ................................................................119 Chapter VII. Discussion and Conclusions ....................................................154 Abilities or Potential of This Approach. 154 Discussion oT Case S tu d ie s .............. 155 iii Literature Cited ..............., .............., ..........................r ................................... 1 60 Glossary, , . , ....................167 Appendix A - Modal Subroutines, Variables, and Program C o d a , ...................................................................................170 Appendix B - Survey Questionnaires. , , . r , „ . , , , . 253 V ita.......................................................................................................................................263 i v ACKtiONLBDOBHfcHTS I Wish to tx p ra ss my a p p re c ia tio n to Drs. Herbert H. Austin and William J. Hargis Tor their guidance and encouragement during the course of thia study. I am particularly indebted to Or. Hargis for financial support received through a research asaiatantship in hia 1abora tor y. I would also like to thank Professor N. B Theberge and the other members of my dissertation committee Tor their critical revise of the manuscript. Finally, 1 wish to thank my wife Louise for her patience, support and encouragement during my graduate s t ud ies. LIST or TABLES Page Table 1. van Bertalanffy Growth of Surf Cl im l.......................... 26 Table 2. Length-Drained Neat Height Relationship in SurT Clams ......................................................... 28 Table 3. Estimated Recruitment Size in Height and Numbers of Middle A tlantic Surf Clams ( 1965-1 975) .................... 31 Table 4. Population Structure of Mid-Atlantic Surf Clams............................. 33 Table 5, Fishing Power C oefficients in the SurT Clam In d u stry .................... 36 Table 6, Regression Coefficients Describing the Ex-vessel Pries Modal for Middle Atlantic Surf Clams. ................................. 59 Table 7. Mean Characteristics of Vessels Sampled in the Surf Clam Fishing Industry Survey ................. 73 Table S. Mean Vessel Charscteristice Obtained From Vessel Licenses ................. 74 Table 9, Summary of Average Reported Fixed Fishing Costs. ................. 77 Table 10. Electronic Equipment Required for SurT Fishing Vessel Operation ............................................. 78 Table 11. Average Annual Fixed Costs of Vessel Operation ................................... 79 Table 12. Summary of Average Variable Pishing