Koeller: Influence of temperature and effort changes on lobster catches 



69 



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6 





— I 1 1 — 



50 100 150 



Distance from recorder (km) 



200 



Figure 6 



(Top) Average daily temperatures from temperature recorders deployed by in- 

 dex fishermen on their traps during 1994. for the southern (south of Murphy 

 Cove), middle (Murphy Cove to Liscomb) and northern (north of Liscomb) sec- 

 tions of the eastern shore. (Bottom) Pearson correlation coefficients of first 

 differenced temperature data from all temperature recorders deployed by in- 

 de,x fishermen versus distance between instruments in 1994. 



tances greater than about 25 km, the samples should 

 be more closely spaced. On the eastern shore, where 

 the annual average number of fishermen providing 

 information is about 20, the resulting 10-km spac- 

 ing at this sampling level should be adequate to pro- 

 vide a representative sample. 



Although these results have not eliminated the 

 possibility of temperature-induced changes in 

 catchability, they do indicate that quantifying these 



changes with fishermen's data would be extremely 

 difficult. 



Acknowledgments 



I wish to thank the Nova Scotia lobster fishermen 

 who provided information used in this study, espe- 

 cially those who have collected data since the begin- 



