Pomphorhynchus heronensis and restricted movement of Lutjanus carponotatuson the Great Barrier Reef

Samples of Lutjanus carponotatus (Lutjanidae) from reef flat (shallow) and reef slope (deep) sites around Heron and Wistari reefs on the southern Grea t Barrier Reef were examined for Pomphorhynchus heronensis (Acanthocephala) . Individual fish from the reef slope had 0-9 (2.6) worms as compared with 1-122 (39.6) worms for individuals from the reef flat (P<0.0001). Other var iables (year, season, size of fish) made little contribution to the variati on. Reef flat and reef slope sites were separated by as little as 300 m. Th ese results imply both that the fish have very limited local movement and t hat transmission of the parasite is concentrated locally.