Sea lion death sparks call for science review

As another endangered sea lion is killed by the squid fishery, Otago scientists have reiterated their calls for the science behind the fishery's management to be reviewed.

It is the fourth known sea lion capture by the Auckland Islands squid fishery in the past four seasons - three were captured in 2013 and none in 2011 and 2012.

Government-employed observers were on 90% of the squid boats, up from about 80% last year.

University of Otago zoologist Bruce Robertson said sea lion deaths were to be expected as trawl fishing was dangerous to the species and although many in the fishery used sea lion exclusion devices (SLEDs), research questioned their effectiveness.

''The Government needs to show leadership. While it [squid] is an important resource, it needs to also value sea lions and the marine environment.''

A review of the five-year management plan released last year raised questions about the inputs and assumptions used in the model on which sea lion management was based, he said.

The review panel said delaying reassessment of the situation and management for five years ''appears inherently risky, in the face of the unknown uncertainty around the model's predictions''.

''It rang alarm bells,'' Mr Robertson said.

''The review of the modelling needs to be done urgently, not dependent on MPI's (Ministry for Primary Industry) budget.''

The five-year plan also needed to be revoked until there was clear evidence that exclusion devices worked, he said.

Added to the concerns were worries the number of pups born in the Auckland Islands was down this year, but that had not been confirmed by the Department of Conservation.

New Zealand Sea Lion Trust spokesman Steve Broni said Otago's sea lions did not appear to have had a successful breeding season either. Many females could not be found, despite intensive searching by volunteers.

''As the recent sea lion population model review suggested, we need a more cautious approach to by-catch and reviewing the by-catch limit every five years for such an endangered species is unacceptable.''

Forest and Bird wanted the squid fishing industry to start using more sustainable methods.

''We would like the industry to change from trawling, in which sea lions can get caught in the giant nets and drown, to jigging, which uses hooks. Jigging is safe for sea lions and would still allow the fishing industry to catch high-quality squid,'' Forest and Bird marine conservation advocate Katrina Subedar said.

Squid nets have exclusion devices, which were meant to allow sea lions to exit the nets but sea lions could suffer injuries when escaping or they could drown.

''We simply do not know whether sea lions survive when they are ejected through the exit holes.''

An MPI spokesman said no triggers had been breached with the recent sea lion death so MPI would continue to implement the SQU6T operational plan.

''But we continuously monitor developments and, if any new information triggers any of the current management settings, we will revisit them.''

The management framework aimed to minimise interactions between fishing vessels and sea lions, but recognised a small number of captures might still occur. Seafood New Zealand Deepwater Group fisheries specialist Richard Wells said it was regrettable a sea lion had been caught but the fishery was using exclusion devices, the ''best available mitigation'' to prevent doing so.

Squid fishing was not the direct cause of the decline in sea lion numbers in the subantarctic, he said.

''It's a population problem. We understand the fishery needs to be managed and observed. Our activities are not the cause.''

There were many factors involved in declining pup numbers and the industry helped fund research into the problems the sea lions were facing, he said.


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