Rocío Mariano-Jelicich (Grupo Vertebrados, Instituto de Investigaciones Marinas y Costeras CONICET – UNMdP, Mar del Plata, Argentina) and colleagues from the same institution have looked at the contribution of fishery discards to the diet of Black-browed Albatrosses Thalassarche melanophris during the non-breeding in the South Atlantic. Their findings have been published recently in the online version of the journal Marine Biology.
The paper's English abstract follows:
“Black-browed albatrosses (Thalassarche melanophris) disperse over the Argentinean Continental Shelf and neighboring waters during their non-breeding season. It is one of the most frequent seabirds attending fishing vessels and also the most common Procellariform [sic] in the bycatch of longliners and trawlers in the area. Understanding the use of fishery discards by this species is an important issue when assessing the potential effect of strategic discard management in decreasing the abundance, interactions, and mitigating mortality. In the present study, we analyzed carbon and nitrogen stable isotope compositions in the blood of Black-browed albatrosses to assess the relative contribution of discards from different fisheries to the diet of this species in winter. Samples were obtained in winter 2011 from fishing vessels operating between 41–43°S and 57–59°W. No sex differences in δ13C and δ15N were observed. Results indicate that during their nonbreeding season, isotopic signatures of Black-browed albatrosses are closer to discards and offal generated by fisheries and in particular by trawlers. The large fishing effort of trawl fisheries in Argentina highlights the urgency of an exhaustive analysis to find practical and effective ways to reduce the number of seabirds attending trawlers”.
Black-browed Albatrosses gather behind a trawler in the South Atlantic
Photograph by Graham Parker
Reference:
Mariano-Jelicich, R., Copello, S., Seco Pon, J.P. & Favero, M. 2013. Contribution of fishery discards to the diet of the Black-browed Albatross (Thalassarche melanophris) during the non-breeding season: an assessment through stable isotopes analysis. Marine Biology DOI 10.1007/s00227-013-2320-7.
Juan Pablo Seco Pon, South American ACAP News Correspondent, 28 November 2013