Journal Article

Sub-Antarctic fur seal, Arctocephalus tropicalis, crossing hemispheres far offshore at São Pedro and São Paulo archipelago, Brazil

Oliveira, Larissa R, Sousa-Lima, Renata S, Bassoi, Manuela, dos Santos, Fernando José, Lins Oliveira, Jorge E

2022

Overview

Unusual records of marine organisms beyond their known distribution range aid the identification of dispersal capabilities, health issues, changing oceanographic patterns and/or anomalies, and may drive attention to underlying shifts in the polar marine environment. Here we report on an adult male sub-Antarctic fur seal, Arctocephalus tropicalis, sighted at Saint Peter and Saint Paul archipelago, also known as Arquipélago de São Pedro e São Paulo (ASPSP) (00° 56′ N; 29° 22′ W), Brazil, on January 18–21, 2022. The animal appeared healthy and stayed in the rocky islands of the archipelago making frequent incursions to sea. We have compiled information from wandering individuals A. tropicalis and found that this is the first indisputable record for the species in the ASPSP, crossing the ecuador to the Northern Hemisphere. We suggest that it comes from Gough or Tristan da Cunha islands which are the closest breeding locations of this species. Therefore, this male traveled at least ~ 5500 km from the natal area and was 1931 km north from the second northernmost sighting of this species in Ascension Island. We speculate that this species may be using currents and/or shallower mid-ocean ridges to guide dispersal routes from subpolar regions to the North.

• Publisher: Springer Nature B.V
• Subject: Anomalies / Aquatic mammals / Archipelagoes / Arctocephalus tropicalis / Biological surveys / Biology / Breeding / Dispersion / Islands / Males / Marine environment / Marine mammals / Marine organisms / Mid-ocean ridges / Northern Hemisphere / Ocean currents / Offshore / Polar environments / Ridges / Species