100


A modification of Snedaker's drop net, a floating frame

version easier to erect and move and causing less bottom

disturbance, was designed by sampling assistant E. Sroka

and built by C. Adams. This version of the net was used in

the pond for August and September collections.



Analysis of Data

 Lengths (standard length of fish and carapace length

of crustaceans), sex (of Gambusia only), reproductive

condition, and wet and dry weights were recorded for

individual specimens in small collections. In large

collections, specimens were divided into species and size

classes, which were weighed as units. These data were

compiled to provide the following information for each

sampling date and location: dry weight per square meter,

average dry weight of individuals of each species, number

of individuals of each species per square meter, number of

females per square meter, and number of gravid females per

square meter.

 Standard statistical parameters of the normal

distribution (Sokal and Rohlf, 1969) and Morista's index of

distribution (Southwood, 1971) were computed; and analysis

of variance, the G-test, and the Mann Whitney U-test (Sokal

and Rohlf, 1969) were used to help interpret the data.

Stomach contents of representative specimens of Gambusia,

gar and sunfish were examined and recorded.