(5) Probability modes and 14% groupings of 

 length are comparable and possibly indi- 

 cate age or molt groups. 



(6) The cluster samples show (a) fairly uni- 

 form mean lengths by day, month, and 

 year; this mean length is approximately 

 89-mm (3.5 inches) carapace length, (b) 

 the mean weight is more variable but is 

 explained, to some extent, by the per- 

 centage of culls, (c) the percentage of 

 females is usually around 50% on a 

 monthly and yearly basis, (d) the sub- 

 jective measure of the percent shedders 

 shows a proportionate increase usually 

 from July through October in each year. 



(7) The catch in numbers per trap -haul -set- 

 over-day is a better indicator of stock 

 density than any other known ratio, pro- 

 vided it is carefully analyzed. 



(8) Fishing effectiveness has increased from 

 1955 to 1970. 



(9) Trap limitations as proposed by some 

 fishermen and legislators will not di- 

 minish the effective effort. 



(10) The solved von Bertalanffy Growth Equa- 

 tion is: 



l t = 266.77 [ / 



0.04785 (( + 0.77250) 



ACKNOWLEDGMENTS 



I find it a pleasure to commend others who 

 have played an integral part in an investiga- 

 tion. 



Specifically, I would like to thank the fisher- 

 men and dealers who allowed, often at an 

 inconvenience to themselves, "bug-hunters" to 

 gather the information for this report. 



The sampling crew, Paul J. DeRocher (who 

 worked from 1966 to 1970), Clarence C. Burke, 

 Gary A. Robinson, and Louis M. Kazimer, has 

 my deepest appreciation. These men not only 

 traveled great distances but also worked many 

 overtime hours including weekends and holidays 

 to collect the data. They were also instrumental 

 in the compilation and summarization of this 

 material at the laboratory. 



Jack Watson, National Marine Fisheries 

 Service, Boothbay Harbor, critically evaluated 

 the manuscript and provided many helpful 

 suggestions. In the same agency, Gareth W. 

 Coffin photographed many of the figures in 

 this report. Sheilagh J. Foss, Isabel Barter, 

 and Phyllis Carnahan, Maine Department of 

 Sea and Shore Fisheries, had the tedious task 

 of typing the manuscript and the tables. 



I sincerely thank everyone who assisted me 

 and hope that this paper justifies their endeavors. 



(11) The solved weight-length relationship for 

 the sexes combined is: 



W = 0.001682 L 2 - 82826 . 



(12) Depending on the methodology, the in- 

 stantaneous total mortality ranges from 

 1.1363 (67.9% ) to 2.9188 (94.6% ) while the 

 instantaneous natural mortality ranges 

 from 0.0202 (2.0%) to 0.3467 (29.3%). 

 Therefore, the estimates of the instantan- 

 eous fishing mortality range from 0.7896 

 (54.6%) to 2.8986 (94.5%). An instantan- 

 eous natural mortality of 0.1054 (10%) 

 and an instantaneous fishing mortality 

 of 2.3026 (90%) are more plausible. 



(13) By using the binomial and cubic expan- 

 sion of the simple yield equation with 

 reasonable parameters, the legal mini- 

 mum size should be raised to at least 

 89-mm (3-V2 inches) carapace length. 



LITERATURE CITED 



ABRAMSON, N., and J. TOLLADAY. 



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 BEVERTON, R. J. H., and S. J. HOLT. 



1957. On the dynamics of exploited fish popula- 

 tions. Fish. Invest. Minist. Agric. Fish. Food 

 (G.B.).Ser. II, 19, 533 p. 

 CASSIE, R. M. 



1954. Some uses of probability paper in the 

 analysis of size frequency distributions. Aust. 

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COOPER, R. A. 



1970. Retention of marks and their effects on 

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 CUSHING. D. H. 



1968. Fisheries biology. Univ. Wis. Press, Madi- 

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1955. Lobster maximum size restrictions. Maine 

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56 



