Sea lion pups on the Auckland Islands. Photo by Louise
Urgent interim measures need to be taken to protect the
endangered New Zealand sea lion population given the serious
rate of decline in pup numbers in the Auckland Islands,
scientists and conservationists say.
Conservation Minister Nick Smith announced yesterday Auckland
Island pup numbers had dropped 18%, to their third-lowest
figure in about 20 years, triggering the need for a threat
management plan to be developed ''promptly''.
''[It] shows an ongoing trend of decline over the last
decade. We need to step up our efforts to ensure these sea
lions survive,'' Dr Smith said from HMNZS Wellington at Port
Ross in the Auckland Islands yesterday.
University of Otago scientist Bruce Robertson said while the
move was welcome, he called on the Government to immediately
revoke the operational plan for the Auckland Island squid
fishery, and revert to the ''comparatively more precautionary
previous operational plan'' until the new plan was finalised
and in place.
''This would give fishery certainty of tonnage and all access
to the valuable squid fishery, while giving due acknowledge
to the existing threats and uncertainties in sea lion
management,'' Dr Robertson said.
If fishing continued under the present operation plan, it
would be ''at least another year for pup numbers to decline
WWF-NZ called for ''urgent interim measures'' to protect the
sea lions while the plan was developed.
Marine species advocate Milena Palka said WWF would like to
see an extension of protection from trawling around the
Auckland Islands to protect the foraging ground of breeding
''Any threat management plan needs to be developed quickly,
be based on the best science available and include tangible
goals and measures that will ensure the recovery of the sea
lion population,'' she said.
The New Zealand sea lion mainly breeds on the Auckland
Islands (70% of the species) and Campbell Island (30%), with
small numbers found on Stewart Island. Dr Smith said the
cause of the decline in the Auckland Island sea lion
population was not clear.
''A wider investigation was initiated in 2012 that indicated
that environmental change and prey abundance were likely to
have played a role in the population decline. There is also
evidence that a bacterial disease has reduced pup survival
rates over the last two decades,'' he said.
The number of sea lions caught in trawl nets had declined
significantly due to sea lion exclusion devices. Primary
Industries Minister Nathan Guy said despite high levels of
observer coverage on the fishing boats, only a small number
of incidental captures had been observed in recent years.
''[The devices] are a great innovation but we need to
continue to monitor the use and effectiveness of these
devices,'' Mr Guy said.
Dr Smith said the management plan, set up to trigger when pup
numbers reached 1500, would review ''all the risks and
explore all possible measures'' to ensure their survival.
Options included active field management, such as intervening
to reduce the several hundred deaths from misadventure and
disease, extending or creating new marine mammal sanctuaries,
or additional measures to reduce impacts of fishing.
New Zealand Sea Lion Trust chairman Steve Broni, of Dunedin,
said a review of all the risks facing the sea lions was
published in 2011.
For any new review to have any real credibility, it needed to
have a strong focus on the earlier review's conclusions,
which included the fact decreasing numbers of breeding
females was the result of fisheries-induced resource
competition and fisheries-related by-catch, he said.
''Competition with fisheries, resulting in resource
competition, nutrient stress and decreased reproductive
ability in NZ sea lions, should be a priority area for future
research,'' the paper said.
While disease was present in the population sporadically and
did warrant further research, there was no klebsiella disease
event in 2008, the year of the lowest pup count on record, Mr
Dr Robertson said while there were mixed messages coming from
Dr Smith and Mr Guy, the effectiveness of sea lion exclusion
devices needed to be looked at, given there were questions
raised internationally about how many sea lions survived
being caught in nets with these devices.
''Waiting another year or two to change the current
operational plan is, in the words of the expert panel,
'inherently risky','' he said.
Deepwater Group chief executive George Clement said the group
supported Dr Smith's announcement and would work with the
Government to address the issue of klebsiella bacteria.
The squid fishery was operating well within the old plan's
permitted tow rate.
How quickly those plans were activated was critical and the
industry continued to refine its technology to minimise
accidental captures, he said.