Connectivity of marine predators over the Patagonian Shelf during the highly pathogenic avian influenza (HPAI) outbreak

Abstract

Animal movement and population connectivity are key areas of uncertainty in efforts to understand and predict the spread of infectious disease. The emergence of highly pathogenic avian influenza (HPAI) in South America poses a significant threat to globally significant populations of colonial breeding marine predators in the South Atlantic. Yet, there is a poor understanding of which species or migratory pathways may facilitate disease spread. Compiling one of the largest available animal tracking datasets in the South Atlantic, we examine connectivity and inter-population mixing for colonial breeding marine predators tagged at the Falkland Islands. We reveal extensive connectivity for three regionally dominant and gregarious species over the Patagonian Shelf. Black browed albatrosses (BBA), South American fur seals (SAFS) and Magellanic penguins (MAG) used coastal waters along the Atlantic coast of South America (Argentina and Uruguay). These behaviours were recorded at or in close proximity to breeding colonies and haul-out areas with dense aggregations of marine predators. Transit times to and from the Falkland Islands to the continental coast ranged from 0.2 – 70 days, with 84% of animals making this transit within 4 days - a conservative estimate for HPAI infectious period. Our findings show the incursion of HPAI to the Falkland Islands marine predator community is a highly credible threat, which may be facilitated by BBA, SAFS and MAG connectivity with South America. This information is vital in supporting HPAI disease surveillance, risk assessment and marine management efforts across the region.SignificanceThe recent emergence of highly pathogenic avian influenza (HPAI) in South America poses a major threat to globally significant marine predator populations in the South Atlantic. There is extensive connectivity over the southern Patagonian Shelf between regionally dominant seal and seabird populations, with potential for large-scale pathogen spread. Despite this connectivity, outbreaks of HPAI are unevenly distributed across the region. Connectivity information is integral for regional disease surveillance, predictive modelling and population viability assessments.