Hunt et al.: Movement of Gadus morhua in the Gulf of Maine area 



859 



some indication of the neeti for revising model for- 

 mulations. For example, changes in apparent natu- 

 ral mortality or unexplained changes in fishing mor- 

 tality could be evaluated as the result of losses due 

 to emigration or increases due to immigration. How- 

 ever, stock definition may be further confounded if 

 cod movements have a temporal element and shifts 

 in distribution occur without permanent loss or gain. 



Acknowledgments 



The authors express their appreciation to the many 

 individuals who participated in the at-sea tagging 

 operations and in particular to Francois D'Entrement, 

 a fisherman who joined the 1994 survey. We also thank 

 the individuals finding and returning tags for their 

 interest and co-operation. Don Clark and Jay Burnett 

 provided valuable comments on an earlier version of 

 the manuscript. John Neilson provided many help- 

 ful suggestions from a fisheries management perspec- 

 tive. Suggestions from two anonymous reviewers 

 improved the analysis and clarity of the report. 



Literature cited 



Clark, D. E. 



1996. Assessment of cod in Division 4X in 1996. Cana- 

 dian Department of Fisheries and Oceans (DFO) Atl. Fish. 

 Res. Doc. 96/101, 44 p. 

 Clay, D., W. T. Stobo, B. Beck, and P. C. F. Hurley. 



1989. Growth of juvenile pollock (Pollachius iirc/is) along the 

 Atlantic coast of Canada with inferences of inshore-offshore 

 movements. J. Northwest Atl. Fish. Sci. 9:37-43. 

 Gavaris, S. 



1988. An adaptive framework for the estimation of popula- 

 tion size. Can. Atl. Fish. Sci. Adv. Com. Res. Doc. 88/29, 

 12 p. 



Gavaris, S., L. VanEeckhaute, M-I. Buzeta, and J. Hunt. 

 1993. Yield projections for the transboundary cod and had- 

 dock resources on Eastern Georges Bank. DFO Atl. Fish. 

 Res. Doc. 93/71, 19 p. 

 GuUand, J. A. 



1983. Fish stock assessment: a manual of basic methods. 

 Wiley, Chichester, UK. 

 Halliday, R. G. 



1973. Int. Comm. NW. Atl. Fish., Res. Doc. 73/7, serial no. 

 2909, 19 p. 

 Halliday, R. G and A. T. Pinhorn. 



1990. The delimitation of fishing areas in the Northwest 

 Atlantic. .J. Northwest Atl. Fish. Sci. 10:1-50 

 Halliday, R. G., J. McGlade, R. Mohn, R. N. O'Boyle, and 

 M. Sinclair. 



1986. Resource and fishery distributions in the Gulf of 

 Maine area in relation to the Subarea 4/5 boundary. North 

 Atl. Fish. Org. Sci. Council. Studies 10:67-92 

 Hunt, J. J. 



1996. Rates of sexual maturation of Atlantic cod in NAFO 

 Division 5Ze and commercial fishery implications. J. 

 Northwest Atl. Fish. Sci. 18:61-75 

 Hunt, J. J., and M-I Buzeta. 



1989. Status of the Atlantic cod stock on Georges Bank in 

 Unit areas 5Zj and 5Zm. Can. Atl. Fish. Sci. Adv. Com. 

 Res. Doc. 89/47, 26 p. 

 1996. Biological update of Georges Bank cod in Unit Areas 

 5Zj,m for 1978-95. DFO Atlantic Fisheries Res. Doc. 96/23, 

 37 p. 

 Hunt, J. J., and J. D. Neilson. 



1993. Is there a separate stock of Atlantic cod in the west- 

 ern side of the Bay of Fundy? North Am. J. Fish. Man- 

 age. 13:421-436 



McCracken, F. D. 



1956. Cod and haddock tagging off Lockport, Nova Scotia. 

 Fish. Res. Board Can., Prog. Rep. Atl. Coast Stns. no. 64, 

 p. 10-15. 

 McKenzie, R. A. 



1956. Atlantic cod tagging off the southern Canadian 

 mainland. Bull. Fish. Res. Board Can. 105, 93 p. 

 NEFSC (Northeast Fisheries Science Center). 



1994. Report of the 18th Northeast Regional Stock Assess- 

 ment Workshop. U.S. Dep. Commer., NOAA/NMFS/ 

 NEFSC, Woods Hole, MA. NEFSC Ref Doc. 94-23. 



