New information on close encounters between albatrosses and fishing boats – sciencedaily

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New analysis of encounters between albatrosses and commercial fishing vessels in the North Pacific Ocean offers researchers important new understanding of seabird-vessel interactions that could help reduce harmful encounters.

The new research method, which combines location data from GPS-tagged albatrosses and commercial fishing vessels, allows researchers to accurately identify bird-vessel encounters and better understand bird behavior, environmental conditions and characteristics that influence these encounters.

“It’s hard to conceptualize how often birds encounter vessels on the high seas, but with this new data it’s becoming really obvious,” said Rachael Orben, assistant professor in the College of Science’s Department of Fisheries and Wildlife. Agriculture at Oregon State University. and the lead author of the study. “Some of these birds are in an environment where they see ships all the time, while others are in an environment where they rarely encounter ships.”

The results have just been published in the Journal of Applied Ecology. Co-authors include Leigh Torres, Associate Professor at OSU’s Marine Mammal Institute, and David Kroodsma, Director of Research and Innovation for Global Fishing Watch, a nonprofit dedicated to advancing the governance of the oceans through increased transparency of human activity at sea.

Albatrosses are large, long-lived seabirds that roam widely over the ocean. Three species of albatross are found in the North Pacific: the black-footed albatross, the Laysan albatross, and the short-tailed albatross. All three species are of high conservation concern and the Short-tailed Albatross is listed as Endangered under the Endangered Species Act.

Fishing can provide foraging opportunities for birds, but not without risks, including the threat of bycatch. Bycatch refers to unintentionally caught fish, birds or other animals and includes interactions with fishing vessels and gear.

Researchers have used biologging, the practice of attaching data logging devices to animals, to track individual bird movements at sea for more than 20 years. But they didn’t have a lot of information on the location of the vessels, which is a critical part of understanding the puzzle of the interaction between seabirds and fishing, Torres said.

Torres learned that Global Fishing Watch processes and makes data available from the Automatic Identification System, or AIS, an automatic tracking system that uses transceivers on vessels. The data includes information on vessel size, movement, fishing method and more. Access to data has “changed the game,” she said.

“With their data, you can track individual vessels,” Torres said. “You can get specific information about a vessel’s location, size, type of fishing gear it uses and the vessel’s flag country.”

Global Fishing Watch’s goals include making commercial deep-sea fishing more transparent to the public, improving fishing regulations and ensuring the sustainability of ocean resources.

“This study represents a new frontier in our ability to understand the impact of fishing on marine life,” said David Kroodsma, director of research and innovation at Global Fishing Watch. “Vessel tracking data, collected by satellites and processed through machine learning, can be a powerful tool for analyzing how biodiversity and fishing vessels interact at sea.”

Members of the research team had previously collected tracking data for adult black-footed albatrosses and Laysan albatrosses breeding in the Papah? Naumoku? Kea Marine National Monument in the Northwest Islands. from Hawaii; Laysan Albatross breeding on Oahu, Hawaii; and young short-tailed albatrosses from their colonies in Japan.

Researchers were able to marry data from fishing vessels with tracking data from GPS-tagged albatrosses over the same time periods to identify and locate interactions between birds and vessels in the North Pacific Ocean.

When the birds were within 30 kilometers of a ship, researchers assumed the albatross was aware of the ship’s presence, Orben said. When the bird was within two miles of the ship, researchers assumed a close encounter between the two. The research team then modeled the drivers of these close encounters.

“With these models, we can begin to understand why birds sometimes and sometimes don’t interact with a fishing boat,” Torres said. “This information can help identify how and when efforts should be made to ensure that these interactions do not go badly for the bird. As we begin to identify patterns, we can potentially help mitigate these take events. accessories.”

Among the researchers’ findings:

  • When birds are in a state of transit – where they travel directly from one place to another – they are not likely to stop and engage with a vessel. But when they are in a foraging state, they are more likely to stop.
  • The characteristics of the vessel, including the method of fishing and the nation of the vessel’s flag, did not appear to be factors determining the interaction of a bird with a vessel.
  • In areas where there is a lot of fishing, the Short-tailed Albatross and Laysan’s Albatross are more frequently associated with fishing boats.
  • Short-tailed albatrosses were more likely to stay on a ship longer in light winds.

“These results indicate that it may be more important to use mitigation methods for a fishing vessel‘s bycatch in light wind conditions,” Torres said. “Things like these can help guide efforts to reduce seabird bycatch. The best regulations are the ones that are the least onerous on fishermen and the most effective.

The analytical framework developed by the researchers could be used to study encounters between fishing vessels and other seabirds or marine mammals. The information gathered from studying these interactions could also help inform fisheries management decisions, the researchers said.

“Our study is truly one of the first to examine the small-scale overlap between fishing vessels and marine animals on the high seas, in international waters,” said Torres. “This opens up a whole new understanding of the dynamics between animals and vessels. This work can help the fishing community fish better and help these seabirds survive and thrive.”

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