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sustain year-round populations of sunfish, especially

through dry years, because of the low tolerance of these

species to hypoxia and their vulnerability to predation in

drying ponds.

 Predator fish, which usually have lower rates of

 intrinsic increase than prey fish, do not repopulate ponds

 in which no fish survive the dry season as quickly as prey

 fish.. Therefore, because of lower predation, population of

 prey species may become greater in such ponds than in ponds

 that do not dry completely. A series of years of greater

 than average rainfall will encourage the expansion of the

 predator population, causing prey populations to decline.

 The lowland ponds in the sloughs and marshes often

retain water throughout the year and maintain a sizeable

population of predator fish. Although prey species

populations build up in the flooded marsh during the wet

season, they are rapidly reduced by fish predation as they

are forced into the pond during the dry-down. This loss to

predation was apparent at Mud Lake Pond during the sampling

study.

 Drainage has increased the number of ponds that dry

completely but reduced the frequency with which upland

ponds are connected by migration routes to source areas for

fish, which probably has reduced considerably the number of

ponds that can provide food to Wood Storks and other wading

birds. In the aerial study of 1973-74 it was observed that

numerous ponds in south-central Lee County were not