(2) The pipeline used to carry the sediments to the beach ran paral- 
lel to the base of the dunes and could have acted as a physical barrier 
to the crabs" movement to the beach, thus preventing them from acquiring 
needed food and water. 
(3) Spring recruitment to the ghost crab stock from pelagic sources 
could have been prevented by the increased load of suspended solids in 
the surf zone during nourishment. 
(4) Ghost crabs may have emigrated from the area in response to 
lowered densities of their major prey species, F. talpotda and Donax spp. 
It is not likely that the crabs would be severely affected by the direct 
deposition of beach nourishment materials. Most overwintering burrows lay 
beyond the nourishment zone and thus would not have been covered by the nourish- 
ment. Ghost crabs that were buried would probably have been able to dig through 
the material to the surface since burrows are probably covered naturally by 
winter storms. 
Leber (1977) and Wolcott (1978) have established that the normal behavior 
of ghost crabs is to emerge from their burrows in the upper dunes at dusk and 
then move down to the swash zone to moisten their gills and feed. The pipe- 
line (the route shown in Fig. 5) could have acted as a physical barrier to the 
active ghost crabs; however, several nighttime surveys of the pipeline did not 
reveal aggregations of trapped ghost crabs. Instead it was discovered that 
windblown sand had provided a natural bridge over the pipeline in many places, 
while elsewhere the crabs had simply tunneled under the pipe. Numerous crabs 
were encountered during these surveys, and several were observed to escape 
over the pipeline with no difficulty when they were frightened. These factors, 
coupled with the fact that ghost crabs were collected at the high tide drift 
line, seemed to indicate that the pipeline did not act as an effective deter- 
rent to ghost crab nocturnal activities. 
Insufficient information concerning the ghost crab breeding cycle is avail- 
able to postulate whether the turbidity associated with nourishment may have 
prevented ghost crab larvae from pelagic sources from colonizing the beach. 
In fact, very few larvae were collected during the entire study and none were 
found following nourishment. (Those found were usually taken during corings.) 
A plausible explanation for the decreased number of ghost crabs on the 
nourishment beach is that the crabs left the area in search of food. Ghost 
crabs have been reported to travel great distances in a single night in search 
of food (Wolcott, 1978). Their major food source during warm weather is £. 
talpotda and Donax spp., and populations of these were severely reduced during 
and after the nourishment. 
b. Migrating Consumers of the Surf Zone. Migrating decapods found in the 
surf zone were: speckled crabs, Arenaeus crtbrartus; the lady crab, Ovaltpes 
ocellatus; the ghost crab, Ocypode quadrata; and the blue crab, Callinectes 
sapidus. The blue crab was found infrequently and never represented by more 
than one individual per transect. The speckled crab was reported as the most 
important surf zone decapod by Leber (1977) and by Anderson, et al. (1977); but 
at Fort Macon its abundance was markedly lower than that of the lady crab. 
30 
