UNIT 4 

 NORTHEAST INVERTEBRATE FISHERIES 



within the closed groundfish areas tripled during 

 the first 20 months of closure. Sea scallop popula- 

 tions are characterized by wide variability in year- 

 class strength and little relationship among domi- 

 nant cohorts between the Mid-Atlantic Bight and 

 Cicorges Bank. Several strong year classes resulted 

 in record high U.S. landings in 1990-91 of about 

 17,000 t (Figure 4-2), but landings dropped 

 abruptly in 1993 to only 7,400 t, remaining at 

 about that level during 1 994-96. Sea scallop land- 

 ings declined further to about 6,000 t in 1997, 

 reflecting much poorer recruitment in recent years. 

 Fisheries in all areas depend almost entirely on the 

 growth ot new recruits into the exploitable size 

 range. In the Mid-Atlantic Bight, current land- 

 ings are dependent on poor 1996 and 1997 year 

 classes. Additional areas in the Mid-Atlantic Bight 

 were closed in April 1998 under the authoriry ol 

 the Secretary of Commerce. Given the rapid 

 growth, low natural mortality rates, and early age 

 at entry into the fishery by this species, consider- 

 able yield is currently being foregone because of 

 growth overfishing. 



Atlantic Surfclams 

 and Ocean Quahogs 



These shellfish are harvested with hydtaulic 

 dredges in the U.S. Exclusive Economic Zone 

 (FEZ). The majority of surfclams are taken off 

 New Jersey, while the majorit)'of landings of ocean 

 quahogs now come from Southern New England 

 and Long Island waters. Small quantities of ocean 

 quahogs are also taken off the coast of Maine and 

 sold at a higher price to the raw seafood restau- 

 rant trade (halfshell market). Fisheries for both of 

 these species have been closed on Georges Bank 

 since late 1989 due to the risk of paralytic shell- 

 fish poisoning. Fhey are managed under the 

 Surfclam and Ocean Quahog Fishery Management 

 Plan of the Mid-Atlantic Fisheries Management 

 Council. The primary management tool is a sys- 

 tem of individual transferable quotas allocated on 

 the basis of historical participation in the fisher- 

 ies. 



Surfclam landings increased steadily during the 

 1960's and early 1970's, peaking in 1974. Subse- 

 quently, a succession of poor year classes, com- 

 bined with a large die-off of the surfclam resource 



Landings 

 (:« 1.000 tl 



United States 



I   



I 



_1_ 



_1_ 



_1_ 



1940 1945 1950 1955 I960 1965 1970 1975 1980 1985 1990 1995 



Year 



off the New Jersey coast in 1 976, led to a very low 

 stock biomass and reduced landings. Since 1977, 

 a fishery management plan has regulated total an- 

 nual surfclam landings from the 200-mile Federal 

 zone (where most landings are derived) and has 

 addressed the earlier significant overcapitalization 

 in the fishery. Large year classes spawned in 1976 

 and 1977 off New Jersey and the Delmarva Pen- 

 insula supported the fishery throughout the 1 980's. 

 Evidence from the most recent assessment (North- 

 east Fisheries Science Center, 1998a,h) suggests 

 consistent but modest levels of recruitment. New 

 incoming year classes have supported the fishery 

 in the 1990's. Based on surfclam biomass produc- 

 tion off New Jersey, where most harvesting takes 

 place, there are adequate resources to support the 

 fishery at the current harvest level in the near fu- 

 ture. Recent annual landings from state and Fed- 

 etal waters averaged 27,700 t ('Fable 4-1). 



Ocean quahog landings increased rapidly as 

 the surfclam resource declined in the mid 1970's, 

 and a matket substitute for processed clam prod- 

 ucts developed. Ocean quahogs inhabit relatively 

 deep waters of the Mid-Atlantic continental shelf 

 and Georges Bank. In the Gulf of Maine, they are 

 found relatively near the shore in these cooler wa- 

 ters. Ocean quahogs are one of the longest living 

 (> 100 years) and slowest growing marine bivalves 

 in the world. Current annual landings (recent av- 



Figure 4-2 



Atlantic sea scallop landings 

 by the United States and 

 Canada, 1940-97. 



1 1 1 



