The predation pressures on Black-browed Albatross have been thoroughly researched in remote oceanic areas, but field visits to the colony in the inner waters of Tierra del Fuego revealed a surprising predator-prey relationship.
As the archipelago forms part of the southern tip of South America, the albatrosses on the south side of Tierra del Fuego are within the range of a much wider variety of predators than oceanic colonies. A total of 17 field trips were undertaken there between 2017 and 2020 to monitor the productivity of the colony and observe the role that predation has to play in albatross breeding success.
Direct observations and camera traps revealed the regular occurrence of Andean Condor, Southern Crested Caracara, Chimango Caracara and Turkey Vulture around the colony.
Andean Condors were seen taking albatross chicks on camera trap images (Chris Darby).
The observations made and footage collected revealed that Andean Condor was, alongside Southern Caracara, the principle avian predator affecting the breeding success of Black-browed Albatross in Tierra del Fuego.
Albatross pairs peaked at 64 in 2017 and just three in 2019.
The study of predation at the Black-browed Albatross colony is the first of its kind in the Sub-Antarctic fjords (Richard Collier).
Black-browed Albatross is a conservation priority in the area, with the colony on Islote Albatros forming part of the Seno Almirantazgo Marine Protected Area.
The researchers said that gathering this baseline information on interactions between species is crucial for the conservation of the colony, especially considering that the field trips revealed that one of the main predators, Andean Condor, is a threatened species globally. It is listed as Vulnerable on the IUCN Red List and has suffered from habitat loss and poisoning across much of its range stretching along the west side of South America.
Andean Condor is primarily a scavenger with a preference for large carcasses, but it is known to take eggs and live birds from seabird colonies.
Reference
Droguett, D, Arredondo, C, & 4 others. 2023. Native avian predators for the world’s Black-browed Albatross (Thalassarche melanophrys) breeding colony in inner waters of Tierra del Fuego, Chile. Polar Biology. DOI: https://doi.org/10.1007/s00300-022-03107-3
