About 40 percent of all avocet and 
stilt eggs at the Barrens were taken by 
predators, and another 8 percent of 
nests failed because an adult was killed 
by a predator while incubating. The 
main culprits seemed to be California 
gulls and red foxes, preying on eggs, 
and foxes and great homed owls, prey- 
ing on adults. While the birds can re- 
nest if they lose a clutch early in the 
season, I suspect that the very large gull 
population may be swamping their de- 
fense system. The avocets and stilts 
cannot chase all the gulls and must re- 
turn to their nests without having suc- 
cessfully driven them off. Both the 
American avocet and the black-necked 
stilt formerly nested along the East 
Coast as far north as New Jersey, but 
these eastern breeding populations 
were shot out in times of unrestricted 
gunning. Neither species has reoccu- 
pied this area, but a stilt population has 
survived in Florida. Currently, stilts 
appear to be expanding their breeding 
range north along the coast from Flori- 
da, a few nonbreeding avocets are sum- 
mering regularly along the coast, and 
state wildlife agencies are attempting to 
reestablish a breeding population of avo- 
cets. But burgeoning gull populations in 
these areas could have a significant ef- 
fect on the avocet and stilt recolonizing 
ventures. In the future the remarkable 
antipredator adaptations of avocets and 
stilts may be severely tested. □ 
