Bycatch is one of the main sources of anthropogenic mortality of species of conservation concern worldwide. Between January 2011 and May 2012, ISPRA coordinated a monitoring programme of cetacean bycatch in Italian pelagic trawlers (BYCATCH III extension 2011), funded in compliance with the Regulation (EC) No.812/2004. Other 3 partners participated in the monitoring, data collection and analyses: CoNISMa, CNR ISMAR of Ancona and the University of Florence. Thirteen independent observers monitored a total of 2,735 hauls. The average observation coverage was 2.4% during the duration of the entire project, ranging between 3.4-4.4 % of the regional fishing effort in 2011. Almost all bycatch events were recorded in the northern Adriatic Sea. Bycatch rates of bottlenose dolphins (Tursiops truncatus) and loggerhead turtles (Caretta caretta) were 0,001 (3 events) and 0,010 (18 events) specimen/haul, respectively. The 2011 estimated annual number of bycaught bottlenose dolphins in this fishery for the GSA 17 was 72 specimens (CV=0.55; 95% CIs=39-104). Despite the high degree of uncertainty, this estimate rise some concern about the sustainability of this accidental captures at the Adriatic level. It is urgent to determine whether or not the scale of this mortality, in addition to that caused by all other fishing gears, is sufficient to pose a threat at the population level. The 2011 estimated annual number of bycaught sea turtles in this fishery for the GSA 17 was 358 specimens (CV=0.29; 95% CIs=296-402), 99% of which released alive. The extent of lethal interactions for common thresher shark (Alopias vulpinus), eagle ray (Myliobatis aquila) and bull rays (Pteromylaesus bovinus) should also be evaluated. Bycatch of elasmobranchs commercial species (e.g. Squalus acanthias and Mustelus spp) should also be carefully considered.
La cattura accidentale è universalmente riconosciuta come una delle principali cause di mortalità prodotte dalle attività antropiche a specie d'interesse conservazionistico. Tra gennaio 2011 e maggio 2012, l'ISPRA ha coordinato un programma di monitoraggio di catture accidentali di cetacei durante la pesca a traina pelagica italiana (BYCATCH III - estensione 2011), finanziato in conformità con il Regolamento (EC) No.812/2004. Altri tre partner hanno partecipato al programma di ricerca e monitoraggio: CoNISMa, CNR ISMAR di Ancona e l'Università di Firenze. Tredici osservatori indipendenti hanno monitorato un totale di 2.735 cale. La copertura media di osservazione è stata del 2,4% durante la durata del progetto, con una copertura regionale che andava dal 3,4-4,4 % dello sforzo di pesca nel 2011. Quasi tutti gli eventi di cattura accidentale sono stati registrati nel Mare Adriatico settentrionale. I tassi di cattura accidentale dei tursiopi (Tursiops truncatus) e delle tartarughe marine (Caretta caretta) sono stati, rispettivamente, di 0,001 (3 eventi) e 0,010 (18 eventi) individui per cala. La stima 2011 del numero di tursiopi catturati accidentalmente in questo attrezzo da pesca per la GSA 17 era di 72 individui (CV=0.55; 95% LF=39-104). Nonostante il suo alto grado d'incertezza, questa stima solleva delle preoccupazioni circa la sostenibilità delle catture accidentali di questa specie, a livello di Adriatico. È urgente determinare se la scala di questa mortalità, sommata a quella causata da altri attrezzi da pesca, è sufficiente a porre una minaccia a livello di popolazione. La stima 2011 del numero di tartarughe catturate in questo attrezzo per la GSA 17 era di 358 individui (CV=0.29; 95% LF=296-402), il 99% delle quali rilasciata viva. Anche il grado d'interazione letale per squalo volpe (Alopias vulpinus), aquila di mare (Myliobatis aquila) e vaccarella (Pteromylaesus bovinus) dovrebbe essere valutato; così come la cattura accessoria di elasmobranchi commerciali (per es., Squalus acanthias e Mustelus spp).
Valutazione delle catture accidentali di specie protette nel traino pelagico (BYCATCH IV, estensione 2011)
De Carlo F;Lucchetti A;Notti E;Sala A;Virgili M;
2012
Abstract
Bycatch is one of the main sources of anthropogenic mortality of species of conservation concern worldwide. Between January 2011 and May 2012, ISPRA coordinated a monitoring programme of cetacean bycatch in Italian pelagic trawlers (BYCATCH III extension 2011), funded in compliance with the Regulation (EC) No.812/2004. Other 3 partners participated in the monitoring, data collection and analyses: CoNISMa, CNR ISMAR of Ancona and the University of Florence. Thirteen independent observers monitored a total of 2,735 hauls. The average observation coverage was 2.4% during the duration of the entire project, ranging between 3.4-4.4 % of the regional fishing effort in 2011. Almost all bycatch events were recorded in the northern Adriatic Sea. Bycatch rates of bottlenose dolphins (Tursiops truncatus) and loggerhead turtles (Caretta caretta) were 0,001 (3 events) and 0,010 (18 events) specimen/haul, respectively. The 2011 estimated annual number of bycaught bottlenose dolphins in this fishery for the GSA 17 was 72 specimens (CV=0.55; 95% CIs=39-104). Despite the high degree of uncertainty, this estimate rise some concern about the sustainability of this accidental captures at the Adriatic level. It is urgent to determine whether or not the scale of this mortality, in addition to that caused by all other fishing gears, is sufficient to pose a threat at the population level. The 2011 estimated annual number of bycaught sea turtles in this fishery for the GSA 17 was 358 specimens (CV=0.29; 95% CIs=296-402), 99% of which released alive. The extent of lethal interactions for common thresher shark (Alopias vulpinus), eagle ray (Myliobatis aquila) and bull rays (Pteromylaesus bovinus) should also be evaluated. Bycatch of elasmobranchs commercial species (e.g. Squalus acanthias and Mustelus spp) should also be carefully considered.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
