Maine and as far south as Cape Cod (Groom 1978, pers. com- 

 mun. 5 ) further substantiate this southwesterly movement 

 undertaken by some lobsters (usually the larger mature 

 individuals). 



Another factor likely to be related to movement, particu- 

 larly in view of this study's high return rate, is the time lobsters 

 were at large prior to being recaptured. Mean times (days) at 

 large varied markedly from long (86. 1 ± 3 .4) ( ± 1 SE) at Boothbay 

 Harbor, to medium (70.5 ±2.6) at Kennebunkport, and short 

 (51.8 ± 1.4) at Jonesport. Considering that recaptured lobsters 

 tagged and released at Boothbay Harbor were at large the 

 longest and also traveled the farthest (mean = 4.6 n.mi., 8.5 

 km) (Table 5), the degree of movement seems to be dependent 



Table 5. — Average distances moved by recaptured American lobsters at each 

 tagging area. Sexes were combined since there were no statistical differences 

 between the distances moved by males and females (r = 0.594, 0.301, and 0.677 

 for Kennebunkport, Boothbay Harbor, and Jonesport, respectively; />>0.05). 









A 



«rage 









Number 



nautical miles 





Area 



Sex 



recaptured 



moved (km) 



SE 



Kennebunkport 



Male 



314 



2.33 



(4.32) 



±0.21 





Female 



398 



2.63 



(4.87) 



±0.47 





Combined 



712 



2.50 



(4.63) 



±0.28 



Boothbay Harbor 



Male 



307 



4.62 



(8.56) 



±0.17 





Female 



317 



4.54 



(8.41) 



±0.21 





Combined 



624 



4.60 



(8.52) 



±0.14 



Jonesport 



Male 



351 



3.07 



(5.69) 



±0.39 





Female 



468 



2.80 



(5.19) 



±0.10 





Combined 



819 



2.92 



(5.41) 



±0.18 



upon time at large. However, an examination of the plots of 

 average distances traveled (nautical miles) against time at large 

 (weeks) indicates that after an 8-10 wk postrelease period, dur- 

 ing which time lobsters apparently dispersed from the point of 

 release, there was little if any association between the time 

 lobsters were at large and the extent of movement (Fig. 8). For 

 example, tagged lobsters recaptured near Boothbay Harbor 

 that had been free 6 mo to 1 yr had moved no farther than 

 those lobsters caught after only 2 mo of liberty. Furthermore, 

 8 of 30 (27%) lobsters recaptured after being at large at least 1 yr 

 were caught within 1 n.mi. (1.9 km) of the three release areas. 

 Similarly, Fogarty et al. (1981) reported that lobsters tagged 

 and recaptured along the coast of Rhode Island moved greater 

 distances as the time at large increased to 90 d, after which 

 movement appeared to level off. 



Average distances traveled by recaptured lobsters were 

 calculated for each tagging area (Table 5). Lobsters at 

 Boothbay Harbor moved the farthest (mean = 4.6 n.mi., SE = 

 ±0.14), followed by Jonesport (mean = 2.9 n.mi., SE = ±0.18), 

 and then by Kennebunkport (mean = 2.5 n.mi., SE = ±0.28). 

 These variations in distances moved at each tagging area 

 appear to be associated with the proximity of the release site to 

 neighboring trap fields, the configuration of the immediate 

 coastline, and, possibly, to where the lobsters were originally 

 caught. For instance, at Boothbay Harbor where lobster 

 movement was the most extensive, the liberation area was not 

 only farther from shore relative to the other areas, but also 

 more removed from zones of moderate to intense fishing 

 pressure. Of course these factors, particularly the latter, also 



KENNEBUNKPORT 



20 30 tO 50 60 70 



90 OO 



« 7 













BOOTHBAY HARBOR 





















































































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» 



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o o OO 





u 4 













o o O 





















en 3 









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50 GO 



JONESPORT 



TIME AT LARGE < *••*■) 



5 W. Groom, Fishery Biologist, New Brunswick Department of Fisheries, 

 Fredericton, New Brunswick, Canada, pers. commun. March 1980. 



Figure 8. — Average distances (nautical miles, 1.9 km) traveled by tagged 

 American lobsters during weekly time intervals prior to recapture. Mean 

 distances were calculated by dividing total miles moved by tagged lobsters recap- 

 tured during a given week by the number of recaptures that week. 



explain why Boothbay Harbor recaptures were at large the 

 longest. 



Most tagged lobsters remained in the vicinity of the release 

 areas as indicated by the fact that 74, 92, and 98°/o of the returns 

 at Boothbay Harbor, Jonesport, and Kennebunkport, respec- 

 tively, were caught within a 5 n.mi. (9.3 km) radius of the 

 release site and only about 1 % of the recaptures wandered > 10 

 n.mi. (18.5 km) (Table 6). Even more restricted movement pat- 

 terns were observed by Harriman (see footnote 3) and Cooper 

 (1970) who reported that most lobsters tagged near Monhegan 

 Island were recaptured within 2 n.mi. (3.7 km) of the island. 

 Similarly, based on observations made by scuba divers and 

 from research submersibles on lobsters near Boothbay Har- 

 bor, Cooper et al. (1975) concluded that large-scale seasonal 

 movements on and off the shallow (<24 m) inshore fishing 

 grounds (notion of many fishermen) do not occur. More 

 recently, Fogarty et al. (1981) noted that the majority of tag- 

 ged lobsters released along the Rhode Island coast were 

 recovered within 3.2 n.mi. (6 km) of the release site. 



The association of lobster size with movement was evaluated 

 by averaging the miles moved by lobsters in 5 mm CL 

 increments and then plotting these values against carapace 

 length (Fig. 9). Although there appears to be no relationship 

 between size and movement, it should be noted that only 2.2% 

 of the lobsters tagged in this study were > 100 mm CL, and 

 according to the studies of Dow (1974) and Groom (see foot- 

 note 5) the majority of major migrants along the Maine coast 

 exceeded 100 mm CL. Aside from the fact that relatively few 

 large lobsters (>100 mm CL) were tagged in this study, it 

 should also be mentioned that only 19(34.5%) of 55 recaptures 

 > 100 mm CL were at large more than 3 mo and only 4 (7.3%) 



