KROUSE and THOMAS: EFFECTS OF TRAP SELECTIVITY ON LOBSTERS 



RECOMMENDATIONS 



Based on the foregoing analysis of the effects 

 different lath spacings have on the size composi- 

 tion of lobster catches, we recommend that all 

 lobster traps fished along the Maine coast have an 

 escape vent of 1% inches. Of course, if the 

 minimum legal size (81 mm) is increased then the 

 vent size should be altered accordingly. 



We emphasize that it is not necessary for the 

 entire trap to consist of the desired lath spacing; 

 but rather, only one lath spacing either on the side 

 or end (preferably near the bottom) of the parlor 

 section of the trap. The remaining laths could be 

 spaced at the fisherman's discretion. 



We believe an escape port (vent) fabricated 

 from some type of durable material and manufac- 

 tured to our specifications could be incorporated 

 into any conventional lobster trap (Figure 1). 

 Merits of this vent would be: 1) easy installation in 

 both new and old traps without requiring drastic 

 modification; 2) modest cost to the fishermen; and 

 3) retention of its original dimensions over time 

 (unlike wooden laths which eventually wear, caus- 

 ing a larger opening, thus permitting escapement 

 of legal lobsters). 



If this recommendation of venting traps is 

 adopted as a conservation measure, we would ex- 

 pect reductions in: 1) the number of culls (which in 

 turn would increase the weight of the total land- 

 ings) and, if of consequence, the natural mortality; 

 2) time expended by lobstermen in sorting their 

 catches; 3) perhaps the illicit trade of sublegal 

 lobsters (shorts) which is considered by some 

 dealers and fishermen to be of an alarming mag- 

 nitude; and 4) if a real problem, the number of 

 lobsters imprisoned in lost traps. 



ACKNOWLEDGMENTS 



We thank the fishermen who allowed us, often at 

 inconvenience to themselves, to accompany them 

 on their fishing trips. Cecil Pierce, a fisherman 

 from Southport, Maine, designed the plastic vent. 

 Gary Robinson, Louis Kazimer, Curt Crosby, 

 Andrew Dolloff, and William Sheldon of the Maine 

 Extension Service made many of these trips. Their 

 comments and experience aided greatly in collect- 



ing meaningful data. We express gratitude to 

 Gareth Coffin, formerly with the Northeast 

 Fisheries Center, National Marine Fisheries Ser- 

 vice, West Boothbay Harbor, Maine, for his pho- 

 tographic work. 



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