Scientists put GPS on albatross, seems they like ships

The findings of the recently published use of radar detectors to track attendance of albatrosses at fishing vessels offers scientists a new way of looking at fisheries risk to seabirds.

The study followed the foraging patterns of tagged wandering albatrosses from the Crozet Islands and found widespread attendance of foraging birds at fisheries vessels.

Use of radar detectors to track attendance of albatrosses at fishing vessels was authored by Henri Weimerskirch and Julien Collet from the Centre d’Etudes Biologiques de Chize, France, Samantha Patrick from the School of Environmental Sciences at University of Liverpool, Dominique Filippi of Sextant Technology, and Susan Waugh from Museum of New Zealand Te Papa Tongarewa.

The research funded by the French Polar Institute (IPEV) and the European Research Council (ERC) took place in Possession Island in the Crozet Islands, southern Indian Ocean, from January to March in 2015 and 2016 and used newly developed technology to log bird activity.

Fifty-three incubating wandering albatross were fitted with XGPS radar loggers in the field. The radar signals emitted from vessels were detected by an omnidirectional micro strip antenna integrated with the bird’s geo-positional GPS device.

Henri Weimerskirch from the Centre d’Etudes Biologiques de Chize says this study is incredibly important, as albatrosses are well-known ship followers and their populations have been severely impacted through accidental mortality due to their encounters with fishing vessels.

“The wandering albatross seek discarded fishery waste from vessels, with potential deleterious effects on worldwide populations,” he says.

Te Papa Senior Curator, Sciences Susan Waugh explains that the newly developed XGPS radar loggers detect vessel radar signals and were used to study the extent of overlap between the albatrosses and fisheries vessels.

“Being able to detect the presence of vessels throughout a species’ range is essential to derive comprehensive encounter, attendance and mortality rates and detect changes in foraging behaviour triggered by the presence of vessels,” she says.

The research found that during breeding, tagged Crozet wandering albatrosses patrolled over an area of more than 10 million square kilometres and as much as 79.5% of birds equipped with the loggers detected vessels, at distances up to 2500 kilometres from the colony.

“This high rate of encounter shows that a far higher proportion of the population are exposed to fisheries mortality risk than previously supposed. The tagged birds showed varying patterns of encounter and attendance at vessels that challenge our perception of foraging behaviour of seabirds,” Waugh says.

An estimated 300,000 seabirds are killed annually in longline fishing. These include critically endangered species, such as Tristan and Amsterdam albatrosses, as well as threatened species such as the wandering albatross researched in this study, or New Zealand’s endemic, threatened Antipodean albatross. The new technology will allow researchers to identify which fleets these very rare species interact with, and enable bycatch mitigation actions to be targeted in those fisheries.

Albatrosses are one of the most threatened families of birds internationally, with 15 of the 22 species in the group threatened with extinction. For all the threatened species, longline mortality is listed as a threat to the populations.

Currently the programme is tracking juvenile birds as they make their first flights after leaving the nest. The trip the juvenile Crozet wandering albatrosses take after leaving the nest takes them across the Indian Ocean, into the Tasman Sea and Pacific Ocean, before they return to their breeding site in Sub-Antarctic Crozet Islands in four to five years’ time.

“Research programmes like this mean that we can track encounters and understand the real level of risk posed by fishing in different life stages,” says Weimerskirch.

Use of radar detectors to track attendance of albatrosses at fishing vessels is published on the Conservation Biology online journal.

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