low number of recaptured new-shell lobsters may be attributed 

 primarily to the high rate of return during the first 3 mo before 

 the peak of the molting period. Accordingly, a decidedly 

 higher proportion of those lobsters recovered after 4 mo had 

 molted (Table 1). In fact, of 46 lobsters recaptured after the 

 first season (1975) at all release areas, 28 (60.9%) had molted. 



Molt increments in weight ranged from 21 .9 to 64.4% (40.9% 

 mean) at Boothbay Harbor, 21.3 to 52.8% (39.8% mean) at 

 Kennebunkport, and 27.3 to 67.5% (46.2% mean) at Jonesport 

 (these values exclude lobsters with missing chelipeds). 

 Increases in carapace length were 7.3-18.1% (12.7% mean) at 

 Boothbay Harbor, 11.5-16.0% (13.1% mean) at Kennebunkport, 

 and 10.6-18.5% (15.1% mean) at Jonesport. Variations between 

 area molt increments are reflected by the analysis of 

 covariance which indicated significant differences (P = 0.05) 

 between the coefficients of the linear regressions of postmolt 

 carapace length on premolt carapace length (Fig. 4). Despite 

 these differences in growth increments by area, which might be 

 resolved with additional data, the overall increase in carapace 

 length (areas combined) approximates Dow's (1964) estimate 

 of 14% for Maine lobsters. 



Estimates of von Bertalanffy growth parameters (Gulland 

 1969) were not realistic (negative K and very low Z,„ values) 

 due to the highly variable growth increments, small sample 

 sizes, and the limited range of sizes and ages represented by the 

 data. 



I20r 



no 



100- 



KENNEBUNKPORT 



+ \.o** 



N--I0 

 r=0.93 



120 



< 100 



cr 



< 



90 - 



90 



BOOTHBAY HARBOR 



100 



.A* 



+ \2** 



N= 25 

 r= 0.94 



85 



90 



95 



100 



I- 



\zo 





















JONESPORT 





no 



. 









•-----"" 



100 

 90 



— u 



j_ 



' 



' 



N=23 

 r = 0.94 



l 1 



Figure 4.- 



85 90 95 100 



PREMOLT CARAPACE LENGTH (mm) 



-Premolt-postmolt carapace length relations of recaptured tagged 

 American lobsters that molted at each release site. 



Movement 



Before movement trends of recaptured tagged lobsters can 

 be thoroughly analyzed, it is necessary to consider the inten- 

 sity, distribution, and seasonality of fishing effort at each 

 release site. Unfortunately, sufficient data were not available 

 to quantify effort by area; however, in view of catch and effort 

 information of the Maine commercial lobster fishery collected 

 coastwise by DMR's Lobster Research Project personnel, it 

 was apparent that fishing pressure was extremely intense at all 

 tagging areas. Seasonal changes in fishing intensity and loca- 

 tion of lobster trap fields are well-known occurrences along 

 the Maine coast (Dow 1961; Thomas 1973; Cooper et al. 

 1975). During the summer-fall period when the most intense 

 fishing activity occurs, most traps are rather uniformly 

 distributed along the shores of the mainland, around islands 

 and ledge outcroppings where usually rough, rocky substrates 

 provide ideal lobster habitat. In winter and spring when fishing 

 effort is minimal, most traps are moved to deeper water (>30 

 m) (Cooper et al. 1975) where 1) traps are less apt to be 

 damaged or lost due to severe winter storms, 2) warmer water 

 temperatures cause lobsters to be more active and subse- 

 quently more catchable, and 3) lobsters are now more abun- 

 dant due to the fact that most traps are fished in shoaler water 

 (<30 m) during the warmer months. 



Another factor which should be considered when assessing 

 movement trends of this study was the release of tagged 

 lobsters at locations differing from those of original capture. 

 Nevertheless, as mentioned previously, all lobsters tagged and 

 released at a certain site were caught within that general area. 



Movement patterns were initially assessed by plotting the 

 points of recapture at each release site (Figs. 5-7). Of the Ken- 

 nebunkport releases (Fig. 5), most lobsters were recaptured in 

 close proximity to shore within a 5 n.mi. (9.3 km) radius of the 

 release site. Only 14 recaptures traveled >5 n.mi. and 10 of 

 these lobsters moved in a southerly direction. The most 

 notable movements were by a male (90 mm CL) which was at 

 large 369 d and traveled 63 n.mi. (116.7 km) to Boston and a 

 female (88 mm CL) which was allegedly caught near Tiverton, 

 R.I. (185 n.mi., 342.6 km), 199 d after release. 



At Boothbay Harbor (Fig. 6), most lobsters were recovered 

 between the mouths of the Kennebec and Damariscotta Rivers. 

 Only one lobster was recaptured in the Damariscotta River, 

 while none was reported from the Kennebec River. By con- 

 trast, numerous tagged lobsters were returned from the 

 Sheepscot River estuary. Twelve lobsters traveled ^.10 n.mi. 

 (18.5 km) up this estuary. Significant easterly and southerly 

 movement was limited to a female (87 mm CL), at large 23 d, 

 that traveled 14 n.mi (25.9 km) to Monhegan Island; a male 

 (107 mm CL), at large 88 d, which moved 42 n.mi. (77.8 km) 

 to Cape Porpoise; and a female (99 mm CL) caught at Jeffreys 

 Ledge (61 n.mi., 113.0 km) after 197 d at liberty. 



In comparison with other areas, directional movement of 

 Jonesport recaptures appeared to be less restricted (Fig. 7). 

 Although several lobsters were recaptured seaward of the 

 release locations, most were taken inshore. The greatest 

 movements (^.20 n.mi., 37.0 km) were by three lobsters that 

 traveled southwesterly. The farthest distance moved was 134 

 n.mi. (248.2 km) (to Kennebunkport) by an 89 mm CL male at 

 large 405 d, followed by a 29 n.mi. (53.7 km) trek to Great 

 Duck Island by a small male (81 mm CL) at large 49 d, and a 



