171

 Interior Geological Survey, 1975 and 1976) for the same

 period indicates that conditions in the study area were

 representative for the entire marsh between the lake and

 the pond. According to a USGS quadrangle sheet, the rim of

 Lake Trafford is less than 20 ft (6.1 m) HSL, suggesting

 that the lake is connected to Corkscrew marsh-strand system

 when water levels are above approximately 19 ft (5.8 m).



 Area of Attraction

 The area of attraction of a pond is that area which

provides f6od for maintenance and growth of the fish that

concentrate in the pond during the dry season. The area of

attraction of the study pond is estimated to be 218 acres

(88.2 ha). Figure 40 is a copy of the photographic overlay

used to make this estimate.



Species Composition and Relative Contribution to Biomass

 The most important species in the study area were

Mosquitofish (Gambusia affinis), crayfish (Procambarus

alleni), Bluegill and Redear sunfish (Lepomnis macrochirus

and Lepomis microlophus), and Florida gar (Lepisosteus

platyrhincus). Mosquitofish and crayfish were the most

frequent and abundant species in the collections from the

marsh, and had the greatest biomass for the area of

attraction. Florida gar made up most of the weight of the

combined samples for all collecting dates because of the

heavy concentration in the pond during the dry-down. Table