Origin of stable flies (Diptera: Muscidae) on west Florida beaches: electrophoretic analysis of dispersal.

Stable fly adults were collected from 16 locations within the state of Florida and from locations in six other states in an attempt to determine the source of stable fly populations along Florida beaches on the Gulf of Mexico. Electrophoretic analyses were made of a minimum of 10 enzymes in each of 37 separate populations. Extremely low heterozygosity resulted in an inability to use standard genetic identity and distance procedures for determining the divergence of allopatric populations to establish the source of flies captured from beach areas where reproduction was unlikely. Comparisons of rare alleles in populations grouped geographically, computations of number of possible migrants, and analysis of conditional average frequency of alleles led to the conclusion that flies captured on Florida beaches come from a variety of sites, with locations northwest of the beaches contributing the majority of flies in outbreaks.