Seascape modeling of southern giant petrels from Patagonia during different life-cycles

SÁNCHEZ-CARNERO; GABRIELA S. BLANCO; FLAVIO QUINTANA; JUAN P. PISONI

MARINE BIOLOGY

SPRINGER

Lugar: Berlin; Año: 2017 vol. 164

0025-3162

Presence-only models such as Ecological NicheFactor Analysis (ENFA) compare distributions of environmentalvariables and species, generating habitat suitability(HS) maps. Here, we determined the factors affectingdistribution of southern giant petrels (SGP) from northernPatagonian colonies (Isla Arce: 45° 00ʹS; 65°29′W, and IslaGran Robredo: 45°08ʹS; 66°03′W) using ENFA, improvingestimates of their potential year-round feeding habitats.Data on movements of 17 adult and 9 first-year juvenileSGP were gathered using satellite telemetry. Model ecogeographicalvariables (EGV) overlapped the tracked animals.The resulting HS maps included most of the trackinglocations along the Argentinean Shelf and reflectedcharacteristics that congregate procellariiformes elsewhere.Wind conditions and primary productivity shaped foragingHS of petrels over the year. However, different EGVs influencedthis population differently depending on the requirementsof their life stage. For example, juveniles showedhigh marginality (values of EGVs different from the meanvalues available). Breeding adults´ HS was determined bya small range of values within those available, showinghigh specializations. Contrarily, wintering petrels showed plasticity in the selection of their foraging environmentsbeing distribution of fisheries one of the variables influencingtheir distribution. This study highlights the importanceof the Argentinean Shelf for conservation of the marineenvironment.