Biological Sciences

Environmental Biology of Marine Teolost Fish

A number of projects are underway examining the environmental biology of marine teleosts.

Hamed Al-Gheilani is examining the effects of upwelling off the coast of the Sultanate of Oman on local fish species. There have been occasional mass fish kills noticed off the Omani coastline, which had been thought to be due to blooms of toxic dinoflagellates. However, recent oceanographic data has suggested that one of the main reasons for the mass fish kills is due to hypoxia. Therefore, Hamed is investigating the tolerances of Omani coastal fish to hypoxic water and also monitoring the physiological and biochemical effects of hypoxic water on these species. The work mostly involves laboratory based studies.

Alberto Kavadellas is examining the effects of the aquaculture environment on the health and disease status of a cultured Pacific species of fish, the white seabass. The culture of this species is relatively new and has arisen because of the depletion of wild populations due to overfishing. The aquaculture of this species has involved a combination of culturing through to harvesting and also some ranching and release of farmed juveniles. Alberto has been investigating what types of parasites are present in the cultured fish and also the health status of various organs in the fish at different stages of the farming process. Moreover, he has been comparing the disease status and health of ranched fish with that of wild fish in the coastal areas off California.

Past projects have involved examining the effects of environmental pollutants on the early life stages of marine fish. These early life stages (embryos and larvae) are commonly thought to be the most vulnerable stage of fish to environmental pollutants and other variables. We have been studying the effects of a variety of pollutants (oestrogenic compounds) and Industrial wastewaters on the embryos and larvae of the turbot (Scophthalmus maximus). Turbot embryos and larvae are available virtually all year round from farmed sources and they can be easily cultured in the laboratory.

Turbot larvae a few days after hatching	Section through a head of a turbot larva

Some of the endpoints measured have been protein metabolism and also the effects of environmental conditions on organogenesis and also growth.