Phenological comparison of two braconid parasitoids of the Caribbean fruit fly (Diptera: Tephritidae)

Two species of Braconidae, Diachasmimorpha longicaudata (Ashmead) and Doryctobracon areolatus (Szepligeti), commonly attack the Caribbean fruit fly. Anastrepha suspensa (Loew), in central Florida. There are temporal changes in the relative abundance of the 2 parasitoids, with a tendency for D. longicaudata to become more common as the fruiting periods of various host trees progress. An exception occurs when D. longicaudata declines relative to D. areolatus during the late-autumn and winter fruiting of the citrus fruit calamundin, chi Citrofortuella mitis J. Ingram and H. E. Moore. During the year there is a spring rise and then an autumn decline in the relative abundance of D. longicaudata. This pattern is not explained by any within-tree changes in fruit size or host larval densities. Many changes in relative abundance are consistent with D. areolatus being superior to D. longicaudata in finding host patches, but inferior at exploiting hosts (counter-balanced competition). Seasonal changes in maximum temperatures are also correlated to changes in the relative abundance of D. longicaudata to D. areolatus. It appears that the outcome of the competition between the 2 species is influenced by climatic conditions