UNIT 4 



NORTHEAST INVERTEBRATE FISHERIES 



32 



INTRODUCTION 



Several invertebrate species (i.e., lobsters, 

 mollusks, and shrimps) have long sus- 

 tained the region's most valuable Fisheries. 

 Some of them are quite sensitive to oce- 

 anic temperature changes, and popula- 



tions and catches have fluctuated accord- 

 ingly. While squids are also invertebrates, 

 they are covered in Unit 2 with other "pe- 

 lagic" Fishes. 



SPECIES AND STATUS 



The region's major invertebrate fisheries 

 target five species: American lobster, surf 

 clam, ocean quahog, sea scallop, and 

 northern shrimp (Table 4-1). In 1990 the 

 total value of these five species was $359 

 million. Lobster ($154 million) and sea 



scallop ($148 million) were the most valu- 

 able of all northeast Fisheries landings. To- 

 gether, these five species are valued 

 highest of all northeast commercial fisher- 

 ies. 



Long-term potential yield (LTPY) ■- 

 Current potential yield (CPY) = 

 Recent average yield (RAY) 1 = 



Table 4-1— Average annual, 

 current potential, and long-term 

 potential yields in metric tons (t), 

 and status of utilization of 

 northeast invertebrate fisheries. 

 The LTPY, CPY, and RAY for the 

 unit equals the sum of the 

 species' LTPY's, CPY's, and RAY's. 

 Where the species' LTPY is 

 unknown, the species' CPY is 

 substituted in the sum. 



67,700 t 



104,700 t 



95,300 t 



198&90 average. 

 2 Data for bivalve species are in shucked meat weights. 

 3 Ptovisional LTPY, based on historical landings patterns 



American Lobster 



American lobsters are caught primarily 

 with baited traps; only a small fraction of 

 U.S. landings come from trawling. Lobsters 

 are partially regulated under a Northeast 

 Fisheries Management Council (NEFMC) 

 Fishery Management Plan (FMP). Because 

 most lobsters are caught within state wa- 

 ters, state catch rules usually apply. Amer- 

 ican lobsters are regulated primarily by a 

 minimum carapace length of 3 9 /)2-inch (83 

 mm) in the EEZ and 3'/i-inch in most state 



waters. Fishing mortality rates for both in- 

 shore and offshore populations far exceed 

 the level which would maximize the weight 

 of the catch. One management goal is to 

 increase the size and age of lobsters 

 caught. This would allow many more juve- 

 niles to mature and thereby increase pro- 

 duction of new lobsters. At the same time 

 the larger juveniles caught would increase 

 the landings (Fig. 4-1). 



surf clam and 

 Ocean Quahog 



Surf clams and ocean quahogs are har- 

 vested with hydraulic dredging vessels; the 

 majority of EEZ landings occur off New 

 Jersey and the Delmarva Peninsula. Small 

 quantities of surf clams and ocean qua- 

 hogs are landed from southern New En- 



gland and the Gulf of Maine waters. Fisher- 

 ies for these species are still closed on 

 Georges Bank because of paralytic shell- 

 fish poisoning (PSP) contamination. Surf 

 clams and ocean quahogs are managed 

 under the Surf Clam and Ocean Quahog 



