Cage-Associated Wild Fish Assemblages at Tuna Fish Farms in the Gulf of Antalya (Turkey’s Western Mediterranean coast)

Cage-Associated Wild Fish Assemblages at Tuna Fish Farms
in the Gulf of Antalya (Turkey’s Western Mediterranean coast)
Mehmet Gokoglu*1
, Halil Colak1
1 Faculty of Fisheries, Akdeniz University, TR-07058 Antalya, Turkey
*Corresponding author: E-mail: [email protected] Fax: +90 242 226 20 13
Received 1
st November 2010, Accepted 27th November 2010
Abstract
The aim of this study was to determine the cage-associated wild fish species beneath the tuna fattening cages in
the Gulf of Antalya. The composition of fishes associated within a 50 meter radius surrounding outside and inside
the cages were recorded by SCUBA divers equipped with underwater video and digital photo camera. Cages and the
mooring systems are observed to attract large numbers of both pelagic and demersal wild fish as feed lost from the
farm and profuse fouling increase the cages’ draw as Fish Attraction Devices (FADs). During the study, 53 fish
species belonging to 27 families were recorded around the cages and groups of fish were not seen more than 50m
away from cages. Wild fish were observed to reduce environmental impact on the benthic communities by feeding
on the lost fish and fish pieces. Also, wild fish aggregation around tuna cages could have positive effects for local
fisheries since the farm area may act as small pelagic no-take zone. The number of fish species and their abundance
were reduced after the harvest of the tuna in the cages.
Key Words: Wild fish, cage culture, tuna