Behavior of sterile adult screwworms (Diptera:Calliphoridae) on flowering trees and shrubs [Cochliomyia hominivorax, Texas]

In a south Texas shrub and brush community, sterile adult screwworms, Cochliomyia hominivorax Coquerel (Diptera: Calliphoridae), were observed or collected on 19 of the 23 sampled species of flowering shrubs and trees. Flies were observed feeding, mating, and resting on flowering shrubs and trees. Most of the flies were found on tenaza, coyotillo, and certain Acacia spp., but not on flowering cacti, herbaceous wild flowers, or grasses. Fly activity on a given plant species appeared to be related to blooming patterns and possibly flower color, but activity was not correlated to the density, frequency, or percent coverage of a plant species. Fewer females were collected (46.1%), and less than half (42.5%) were mated. Flies appeared to aggregate, feed, and mate at local flowering vegetation for up to 5 days after eclosion and then disperse or die.