Attraction of wild coastal fishes to an Atlantic subtropical cage fish farms, Gran Canaria, Canary Islands

Abstract

We assessed the influence of two commercial fish farms on the local aggregation of coastal wild fishes through a 'post-impact' sampling design at Gran Canaria Island (Canary Islands). At each farm, we established two controls and one impact location and estimated fish abundance bimonthly by means of SCUBA diving. Results provide evidence of local aggregation in the associated fish assemblages around sea-cage fish farms. Dissimilarities between control and impact locations for both fish farms were due to differences on the abundance of a few species. However, we detected significant differences by means of some assemblages between controls in one fish farm, as a consequence of the removal and re-location of cages. Moreover, we also detected significant within location small-scale variability for several fish assemblages around both sea-cages farms. Otherwise, we did not observe any effect of sampling times.