Spatial use of multiple jurisdictions by Magellanic penguins and assessment of potential conflicts in the face of changing trawl fisheries scenarios

YORIO, P; SUÁREZ, N; DELL'ARCIPRETE, P; MARINAO, C; GÓNGORA, ME; PICHEGRU, L; PROSDOCIMI, L; KASINSKY, T

MARINE ECOLOGY PROGRESS SERIES

INTER-RESEARCH

Año: 2021 vol. 658 p. 219 - 236

0171-8630

Seabirds often have wide distribution ranges and may travelrelatively long distances to breeding  grounds,  often crossing  jurisdictional  boundaries. When  engaged  in foraging  behaviour, seabirds areprone to interact with different fisheries and suffer incidental mortality. We assessedthe spatial use of foraging Magellanic penguins Spheniscus magellanicusbreeding at 3 colonies within the Patagonia Austral Marine Park (San JorgeGulf, Argentina) in relation to different jurisdictions. We also quantifiedtheir spatial overlap with 3 trawl fisheries and bycatch (incidentalmortality), an interaction previously reported in the region. BreedingMagellanic penguins ainly used waters under provincial jurisdiction within thegulf, with some use of federal waters depending on the breeding season andcolony location. Spatial use by breeding penguins resulted in a variable butrelatively low overlap with the operations of the 3 fishing fleets in 2014−2016(1.1−26.3%). Changes in the spatial distribution of fishing operations inrecent years resulted in a lower overlap than in 2005−2007 (12.1−60.8%).Incidental mortality during 2008−2014 was also variable and relatively low(0.0−0.363 birds per haul). Breeding Magellanic penguins foraged outsideprotected area boundaries where they can spatially overlap with and facepotential threats from different fishing fleets that operate in waters ofprovincial and/or federal jurisdiction. Despite the current low spatialoverlap, the relatively fast changes in fishing patterns in the recent past drawattention to the need for continuous monitoring. Data obtained in this studymay prove valuable in case the implementation of spatial and temporal closuresof fishing operations is needed.