typically occur in higher salinities than P. pugio. 



• American lobster: After mating, the female holds the 

 spermatophore for about one year before fertilizing the 

 eggs and extruding them onto her pleopods for brood- 

 ing (berried female) . The mating period is not identified 

 by the ELMR Program; instead, spawning (S) for this 

 species is defined as the period of egg fertilization and 

 extrusion. The egg (E) stage is defined as the period 

 when berried females are generally encountered. Fe- 

 males may brood the eggs for up to 1 1 months before 

 they hatch as larvae. 



• Blue crab: Life stages considered are adults (A), 

 mating (M), juveniles (J), larvae (L), and eggs(E). The 

 ELMR Program identifiesthe mating (M) period, but not 

 the spawning period. Mating usually takes place in the 

 low salinities of the upper reaches of estuaries. After 

 mating, females move to higher salinities, while males 

 often remain in the upper reaches of the estuary. The 

 female holds the spermatophore for up to two years 

 before fertilizing the eggs and extruding them onto her 

 pleopods for brooding (sponge female phase). The 

 egg stage is defined as the period when sponge 

 females are generally encountered. Females typically 

 brood the eggs for 1 -2 weeks before they hatch as 

 larvae. Development through the late zoeal stages 

 occurs offshore, then megalopae are transported back 

 into the estuary and disperse throughout the salinity 

 zones. Zoea and megalopae are considered as larvae 

 (L). As they approach maturity, blue crabs seek lower 

 salinities. 



Fishes. Compiling information by salinity zone uses a 

 single fundamental habitat parameter. However, a 

 combination of habitat characteristics, such as bottom 

 type, water temperature, and bathymetry, would more 

 accurately describe the spatial and temporal distribu- 

 tions of many species. Some life history characteristics 

 of ELMR fish species are provided below. 



• Skates: Lifestagesconsideredareadults (A), mating 

 (M), juveniles (J), and eggs(E). Following mating, eggs 

 are extruded in leather-like, horny cases for incubation. 

 Hatching occurs several months after egg extrusion, 

 and the egg stage refers to the period from egg extru- 

 sion to hatching. Upon hatching, young skates are 

 considered juveniles, therefore the ELMR Program 

 does not identify a larval stage for these species. Raja 

 species in Mid-Atlantic estuaries include R. eglanteria 

 (clearnose skate), R. erinacea (little skate), R. ocellata 

 (winter skate), and R. laevis (barndoor skate), 



• Atlantic stingray and cownose ray: Life stages 

 considered are adults (A), mating (M), juveniles (J), 

 and parturition (P). Mating refers to the period of 

 copulation/internal fertilization. Both species are be- 



lieved to be ovoviviparous, i.e. they incubate eggs 

 internally (without maternal nourishment) and liberate 

 live young (parturition). Hence, the ELMR Program 

 identifiesthe parturition stage, but does not identify egg 

 or larval stages for these species. Cownose rays are 

 known to form large schools that enter estuaries to 

 feed. 



• Shortnose and Atlantic sturgeons: Shortnose stur- 

 geon is considered an endangered species throughout 

 its range, and Atlantic sturgeon has been listed as a 

 protected species by the States of New Jersey, Con- 

 necticut, and Rhode Island (Johnson 1987, USFWS 

 1993). Both species are anadromous, occur primarily 

 in large river systems, are slow growing, and long- 

 lived. Spawning may occur in fresh or brackish water, 

 and presumably does not occur every year for indi- 

 vidual females. Atlantic sturgeon eggs are demersal 

 and adhesive, and larvae drift downstream. Juvenile 

 Atlantic sturgeon remain in fresh or brackish water for 

 their first summer, then migrate seaward. 



• American eel: Spawning occurs in the Sargasso Sea, 

 and the pelagic larvae (leptocephali) may spend over 

 a year in marine waters before being transported 

 shoreward. As leptocephali reach the continental 

 shelf, they metamorphose into transparent "glass eels". 

 As glass eels migrate into estuaries and fresh water, 

 they develop pigment and are considered "elvers", 

 which then grow into "yellow eels". Yellow eels inhabit 

 estuarine and fresh waters for years before maturing 

 into "silver eels" and migrating seaward (Fahay 1978). 

 The ELMR program considers silver eels as adults (A), 

 elvers and yellow eels as juveniles (J), and glass eels 

 and leptocephali as larvae (L). Although the egg (E) 

 stage is identified, it is not found in estuarine waters. 



• Blueback herring and alewife: Spawning occurs in 

 the spring, primarily in fresh water above and below 

 head-of-tide. Alewives, however, generally enter riv- 

 ers earlier, ascend farther, and spawn in slower moving 

 water than do blueback herring. Adults of both species 

 typically move seaward after spawning. These two 

 species can be difficult to distinguish, and they are 

 often referred to collectively as "river herring". 



• American shad: An anadromous species with a fairly 

 strong natal homing tendency. Adults spawn in fresh- 

 water rivers and typically die afterwards. Juveniles use 

 low salinity estuarine waters as a nursery area, then 

 move seaward in the fall. 



• Atlantic menhaden: Spawning occurs in the seawa- 

 ter zones of many Mid-Atlantic estuaries. Larvae move 

 inshore, and juveniles use estuaries as a nursery area. 



14 



