Batoids discard in the botton trawl fishery at Puerto Quequén (Buenos Aires Province, Argentina).

CHIARAMONTE, G.; TAMINI, L. L.; PEREZ, J. E.; CAPPOZZO, H.L

Pennsylvania, USA

Congreso; 15th Annual Meeting of the American Elasmobranch Society.; 1999

The Pennsylvania State University

From the 439 coastal vessels working in Argentina, 25 are at Puerto Quequéñ(38o  37' S, 58o  50' W). Bottom trawl (BT), in multispecific fishery, is the most common kind of gear used and the fishing discard is composed by invertebrates, elasmobranchs and finfishes. This work describes the by-catch composition of batoids in BT at Puerto Quequéñ, studied during 1998 winter-spring seasons by on board observed in 24 gear operations. Eleven batoid species were recognized and 599 specimens were weighted and measured disc width. The commercial species were  Raja castelnaui,  R. flavirostris  and  R. cyclophora  . Vessels worked in the same fishing area during winter and spring and each gear operation spent 2.2 Ò 0.3 hours. Batoids was 56 % of the total catch with an average of 220.13 Ò 156.80 kg per operation (83.6 Ò 60.5 kg of commercial biomass) in winter and 309.22 Ò 201.99 kg (56.9 Ò 39.1 kg) in spring. Batoids was 57.2% of the discard in winter and 72% in spring. Electric ray,  Discopyge stchudii, was 78,5% of the race captured (sex ratio 1:0.9; mature males and females 87 and 90%) and all the individuals were discarded . For the electric ray populations and other diferent taxa, BT fishery impact might by important and its effect on benthonic communities has not been measured yet.