Kinorhynch communities from Alabama coastal waters

Abstract

ABSTRACT Recent studies have increased the known diversity and distribution of kinorhynchs in the Gulf of Mexico. For this study, sediment was sampled from Alabama coastal waters at shallow depths ranging from 11 to 26 metres. The 13 stations were positioned to the west and east of the mouth of Mobile Bay as well as at central locations. A total of 320 animals were collected. Animal densities ranged from 0 to 66 ind./10 cm2, with an average of 9.6 ind./10 cm2. The majority of the identified animals (97%) belonged to four species. Animal densities were highest at stations clustered at the mouth of Mobile Bay and correlated positively with higher levels of most trace metals, organic matter and silt/clay. Animal density correlated negatively with total sand, surface salinity and water depth. These data revealed a surprisingly low abundance of animals to the east and west of Mobile Bay compared to higher densities at the mouth of the Bay, suggesting that their populations are heavily influenced by the water entering the Gulf from the Bay. Efflux from the Bay provides a source for finer sediment, which is likely an important driving factor influencing higher kinorhynch diversity and density.