Cultured aquatic animals and plants can be genetically altered either individually (these are termed "genetically modified organisms", or GMOs) or collectively, as a brood or group. GMOs are created by manipulation of the natural genome of individuals. Groups or broods can be genetically altered, compared to conspecific wild populations, by inbreeding, using only a few broodstock individuals, or selection in aquaculture hatcheries. For both of these cases, careful management of the cultured organisms is required because any that escape or are released and subsequently interbreed with wild conspecifics or individuals of closely related species can contribute foreign genes to, or alter the genetic diversity of, the wild individuals.

Widespread farming of genetically modified aquatic animals (principally fish, mollusks, and crustaceans) will be a reality in the not-so-distant future. In a series of presentations, the speakers in this session address a broad spectrum of the types of genetic alterations possible in aquaculture and the interactions of cultured, genetically altered organisms with native populations.

Dr. Anne Kapuscinski will initiate the session with a presentation in which she describes the state of research on the risks associated with aquacultured, transgenic organisms, the procedures for assessing the ecological and human health effects of transgenic organisms as described in an interdisciplinary manual, and research priorities needed in this area.

Dr. Bill Muir will follow with a description of a mathematical model that provides for an assessment of the environmental risks that transgenics would have if they escape or are released and he gives an example risk assessment using the model.

Dr. Uthairat Na-Nakorn will then present a case study of hybridization in which, via inadvertent escapes of culture fish, the genes of the cultured fish species are introgressing into a native, closely related fish species, and the actions implemented to try to stop further interbreeding between the cultured and the wild species.

Dr. Mario Estrada will next describe a comprehensive series of experiments designed to address many diverse potential problems, ranging from ecological damage to human acceptance of the fish for use as food, associated with the culture of a genetically modified exotic species; these studies were conducted prior to the official consideration of the fish for culture.

Lastly, Dr. Theresa Bert will outline a comprehensive program to monitor the genetic impacts of aquaculture-based stock enhancement programs; the program is designed to monitor numerous components of genetic impacts, ranging from severe reductions in the genetic diversity of hatchery broods to the outcome of the stock enhancement program.

Saturday 30 September, 3:50 pm

(This special session has been arranged and sponsored by the International Union of Biological Sciences.)

IUBS-1 Kapuscinski AR
Anne R Kapuscinski
Biosafety assessment of genetically engineered marine organisms: status and needs

IUBS-2 Muir WM
William M Muir and Richard D Howard
Models to access environmental risk from genetically modified organisms (GMO)

IUBS-3 Na-Nakorn U
Uthairat Na-Nakorn and Wongpathom Kamonrat
Genetic impacts of aquaculture stocks on natural stocks of Clarias macrocephalus and Puntius gonionotus in Thailand

IUBS-4 Estrada MP
Mario P Estrada, Rebecca Martinez and Isabel Guillén
Ecological and human-health-effects evaluation of Tilapia genetically modified for growth improvement

IUBS-5 Bert TM
Theresa M Bert, Michael D Tringali, Charles Crawford and Seifu Seyoum
Effects of hatchery-based stock enhancement on the genetic diversity of wild populations