Parasitism of Larval Fishes in a Riverine Overflow Habitat

Parasite loads of 4 larval fish species in a lower Mississippi River overflow pond were compared. Differences in parasite loads appeared to be related to adult spawning locations and larval fish habitat preferences. Allacanthochasmus sp. was the only parasite found in larval fishes, with maximum infestations of I metacercarial cyst in bluegill and 2 cysts in shad and inland silverside. No parasitism was observed in crappie. Total percent parasitism was highest in silverside (mean ± SE, 2.2 ± 0.5%), followed by bluegill (0.9 ± 0.2%) and shad (0.9 ± 0.3%). Results indicated that adult reproductive tactics, larval fish habitat preferences, and cercarial development of Allacanthochasmus sp. may influence rates of parasitism in larval fishes.