This Is How It Ends: '39 wing beats from extinction'

Monday, 18 October 2021

Commercial fishing, introduced predators and climate change are putting penguins and other unique seabirds on the edge of survival. (File video)

Seabirds that call the Hauraki Gulf home are on a “perilous trajectory,” of decline, a new report warns.

State of our Seabirds 2021 estimates seabird numbers in the region have plunged by 69 per cent since humans first settled in New Zealand.

The declines were driven by the catastrophic impacts of introduced predators, such as rats, mustelids, cats, dogs, and human exploitation of seabirds and the ocean as a food source.

The report was produced by the Northern New Zealand Seabird Trust and the Hauraki Gulf Forum, and launched at Parliament on Tuesday.

A fairy tern/tara iti of which there are just 39 in existence.

The Hauraki parekareka/spotted shags “are not far behind”, hanging on in three small colonies.

Population data suggests “at best a lack of recovery and at worst ongoing declines” for species such as terns, gulls, penguins, shags. They are predominantly inshore feeders, call the region home year-round, and are closely dependent on the Gulf’s food web for survival.

The tākapu/Australasian gannet is being forced to adapt to redistribution of nesting sites and changes in prey distribution.

Tākoketai/black petrel and toanui/flesh-footed shearwater are at high risk from being accidentally caught in fisheries, the latter by both recreational and commercial fisheries.

Tākoketai/black petrel breed only on Great Barrier Island and Little Barrier Island, in the Hauraki Gulf.

Migratory seabirds such as petrels, shearwaters, diving petrels and storm petrels are affected by changes to the climate and oceanic food webs beyond the Gulf.

The report says human impact on the Gulf has been particularly profound since 1950 with the industrialisation of commercial fishing. And a disease, introduced from Australia, had “a devastating impact” on pilchard populations, a food source.

“Indirectly there have been major habitat impacts from fishing practices including the destruction of undersea reef and mussel bed habitat through trawling and dredging,” the report says.

On the coast sediment and nutrients derived from farming, deforestation, and increasing urban sprawl have swamped vast areas of coastal habitat in a sea of silt and mud.

However, the report also says recent protection of breeding habitat on some of the Gulf’s islands has “arrested declines and promoted population increases” for some species, although it notes “at levels far below their former abundance.

It points to a “spectacular gain” – the discovery of the New Zealand storm petrel, believed extinct for a century. It was discovered breeding on uninhabited Te Hauturu-o-Toi/Little Barrier in 2003.

A rockhopper penguin on Auckland Island. Penguins are among more than 90 per cent of New Zealand seabirds at risk.

In 2020, the Hauraki Gulf Forum published a bleak report revealing crayfish are “functionally extinct” in some areas of the Hauraki Gulf and snapper and tarakihi populations are struggling.

It warned of the growing impact of overfishing, development and population growth on the Hauraki Gulf Marine Park, which was established in 2000.

Earlier this year, the Government announced a plan to revitalise the Gulf’s environmental health.

This week Stuff launched This Is How It Ends, a seven-part documentary series investigating the biodiversity crisis. It examines why New Zealand has the highest proportion of threatened native species in the world, with more than 4000 at risk.

That includes seabirds, with over 90 per cent at risk, including endemic penguins and the Antipodean albatross.