Different techniques of underwater visual censuses were used to evaluate the presence of alien marine fishes in the Canary Islands (central-eastern atlantic) introduced through oil rigs

Abstract

Volunteer observers (SCUBA divers, professional and recreational fishermen) reported sightings and/or catches of non-native fish species along the north, east, and south-east coasts of Gran Canaria. The number of sightings/catches and the total number of individuals are given for each non-indigenous fish species. For each fish (observed or caught), collection information (locality, coordinates, date, depth, type of substratum, among others) was recorded. Most non-native specimens collected by spearfishing or professional fishing gear were examined at the laboratory for taxonomic identification and determination of sex and maturity condition.