Northern seabirds in decline
A major review of seabird populations in northern New Zealand has shown them to be in serious decline, scientists estimating that up to 90 per cent are at risk of extinction.
Northern New Zealand is a seabird biodiversity ‘hotspot,’ home to some 28 species that breed in the region, five of them found nowhere else in the world, the Northern New Zealand Seabird Trust report saying very little was known about the status of, and threats to, many of them.
“We must first understand what threats these seabirds are up against before we can establish a baseline from which to work on researching and conserving them,” lead author Edin Whitehead, a doctoral student at the University of Auckland, said last week.
Broadly the major threats were invasive species, fisheries, pollution, climate change, disease, and direct human impacts (disturbance and coastal development), the report highlighting the need for rapid action to mitigate those threats.
“Some seabird species we have really only just discovered, such as the New Zealand storm petrel, breeding on Te Hauturu-o-Toi/Little Barrier Island,” coauthor and project co-ordinator Chris Gaskin said.
“It’s quite possible that if the eradication of rats and cats on [Little Barrier] had not happened we may never have known they were there.”
The most vulnerable species included black petrels, threatened by fisheries by-catch, and the fairy tern, whose breeding population had fallen to around a dozen breeding pairs.
While some threats to seabird populations, such as introduced mammalian predators and fishing, were well known, others, such as climate change, pollution (especially plastic) and disease, were only just emerging.
“Although there has been some progress in eradicating invasive species from islands to restore seabird populations, this isn’t enough when they are facing multiple threats both on land and at sea,” University of Auckland associate professor and report co-author James Russell said.
The report was released at the Birds New Zealand (Ornithological Society of NZ) conference in Wellington on Sunday.