The distribution pattern of the three dominant species (i.e., F. talpotda 
in the swash zone, D. parvula absent from the beach, and D, vartabilts present 
on the upper reaches of the intertidal zone) remains until falling temperatures 
in winter force both £. talpotda and D. vartabtlts into deeper nearshore waters 
(Leber, 1977). The fact that these animals do not just die at the end of the 
season is demonstrated by the total absence of empty carapaces and shells during 
the time when the population starts to dwindle. In addition, several investi- 
gators have reported increased numbers of the animals in the nearshore-offshore 
waters at this time (Saloman, 1976; Matta, 1977), and the return in spring of 
adults rather than juveniles (Leber, 1977), 
Emertta talpotda, D. parvula, and D. variabilts are the three most impor- 
tant organisms in the intertidal zone on these beaches. They are numerically 
dominant (Cox, 1976; Saloman, 1976; Matta, 1977; McLachlan, 1977a; Leber, 1977) 
and they also represent the largest component of the total biomass of the 
system (Leber, 1977). Functionally, they provide an efficient system for har- 
vesting planktonic primary production and other forms of particulate organic 
matter for higher level consumers. Thus, they constitute the important first 
link in energy flow through the intertidal system (Matta, 1977; Leber, 1977). 
The high-energy sandy beach intertidal zone has no indigenous higher order 
consumers, and the great amount of secondary production there is largely 
untouched during the daylight hours. After dark, several different migrating 
consumers enter the area to feed. Ghost crabs, 0. quadrata (Fabricius), move 
from their burrows in the upper beach and dune areas. Wolcott (1978) stated 
that the ghost crabs are the top carnivores in a simple food chain based on 
filter feeding. However, Leber (1977) asserted that there are other equally 
important consumers. He stated that the predation by two portunid crabs 
(A. ertbrarius and 0. ocellatus) that migrate in from the nearshore is nearly 
as important as that of ghost crabs. 
The importance of the nearshore and surf zone as recreational areas for 
sport fishermen and as nursery grounds for both sport and commercial species, 
such as pompano, Trachinotus spp., mullet, Mugil spp., whiting, Menticirrhus 
spp., and flounder, Paralichthys spp., has been established (Tagatz and 
Dudley, 1961; Miller and Jorgenson, 1969; Dahlberg, 1972; Cupka, 1972; 
Anderson, et al., 1977). Anderson, et al. (1977) showed the importance 
of these species of fish in terms of biomass, and Leber (1977) demonstrated 
by gut content analysis that these fishes, at least when in the surf zone, 
consume £. talpotda and Donax spp. almost exclusively. The studies cited 
above indicate that EZ. talpotda and Donax spp. serve as important food sources 
for other consumers in addition to ghost crabs. 
Other organisms that occur less frequently than either EF. talpotda or 
Donax spp. include three species of amphipods: 4H. canadensis, a fairly abun- 
dant burrowing amphipod inhabiting the wetter parts of the beach; 7. mega- 
lopthalma, a very active amphipod inhabiting the drier sands near the high 
tide drift line; and A. virgintana, an uncommon inhabitant of the lower swash 
zone. Two species of polychaetes occur commonly on the sandy beach in North 
Carolina also. One is the selective indirect deposit-feeding spionid worm, 
5S. squamata, which occurs interstitially on all parts of the intertidal zone 
(J. McDermott, personal communication, 1978). The other is a slightly larger 
deposit-feeding polychaete, W. ptcta, which Leber (1977) reported as occurring 
at times in the swash and surf zones. The idoteid isopod, C. coeca is the only 
isopod found on the beach. 
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