18 Sep 2018

Going for Green: Chile purse seine project nominated for conservation award

Modifying purse seine nets in Chile seems to offer a promising new way to reduce seabird bycatch. This year, the project has received prestigious recognition from the Latin American Green Awards.

A purse seine vessel off the coast of Chile © Luis Cabezas
A purse seine vessel off the coast of Chile © Luis Cabezas
By Margaret Sessa-Hawkins

In October, the Pink-footed Shearwaters begin to arrive on Robinson Crusoe and Mocha Islands, off the coast of Chile.

Having travelled on an incredible migration up the Western coast of the Americas all the way to Alaska and then back down again, they settle on the small island to lay their eggs and raise their young. Some will succeed in this endeavour, flying out to sea to catch fish which will sustain them and their young over the breeding season. Others, however, will not be so fortunate. While diving for a tasty fish, they will collide with a trawl cable or be caught in a large fishing net. This process, where seabirds are accidentally killed by industrial fishing operations is known as ‘bycatch’, and it is one of the biggest threats to seabirds.

“These [fishing fleets] are fishing in the same areas as these birds. They are capturing the very fish these seabirds eat,” said Cristian Suazo, a member of the Albatross Task Force Chile, which is working to combat bycatch. “The fleets are also out at the same time these birds, many of which are migratory, have the greatest need for food to both refuel and to feed their young.”

Fortunately, efforts over the past decade to lower the numbers of seabirds caught as bycatch have been extremely successful. In 2006, BirdLife and the RSPB (BirdLife Partner, UK) launched the Albatross Task Force (ATF), a partnership dedicated to reducing bycatch in some of the deadliest fisheries for Albatrosses.

The new nets reduce bycatch by 98%, benefiting species like the Pink-footed Shearwater © Mike Baird
In Chile, the ATF has been working since 2007, where it began by trying to reduce bycatch in pelagic longline fisheries. The team used Bird Scaring Lines to prevent birds like Albatrosses from being hooked on lines set for swordfish. The Bird Scaring Lines were a success, substantially reducing bycatch.

In 2013 though, the team noted that there was also bycatch coming from purse seine fisheries, and began working to reduce bycatch in this industry as well. In purse seine fishing, a large net — weighted at the bottom while the top floats along the surface — is spread over a large area. Then, the bottom edges of the net are drawn together, trapping any fish who happen to be inside. The method is extremely useful in catching fish that school, like the sardines, mackerel and anchovies that are so abundant in the Humbolt Current off the coast of Chile, but it can also accidentally catch diving birds, such as the Pink-footed Shearwater, which fly into the nets hoping to eat the fish inside, and then are trapped and drown.

In order to determine how best to reduce bycatch the team began going out to sea with purse seiners, looking for ways fishing could become more seabird-friendly. Thanks to voluntary collaboration with fishermen, members of the ATF were able to observe how birds were getting caught in nets, and also work with fishermen to figure out the best ways to reduce bycatch without affecting their livelihoods.

“We realized we needed to change the way the net’s buoys were installed,” Suazo said. “We also needed to reduce the excess netting that some of the purse seines have, which can create a layer over the water that drowns birds.”

The team therefore created ‘Modified Purse Seines’ or MPSs. Several boats have adopted the new nets, and, experimentally, the nets have reduced seabird bycatch by 98 percent. The success of the MPS has not gone unnoticed as this year, it was listed as one of the best 500 environmental initiatives in Latin America by Premios Latinoamérica Verde (The Latin American Green Awards). The biggest prize for the team, however, is knowing that more Pink-footed Shearwaters, and other seabrids like them, will make it home safe now.