Last year I was contracted by the Northern New Zealand Seabird Trust to do some research into the major threats to seabird populations in northern Aotearoa New Zealand. Our region is a hotspot for seabird diversity – 28 species breed here (between East Cape and the Three Kings Islands), and five of these breed nowhere else. In terms of diversity and sheer numbers of birds, northern New Zealand is internationally recognised as an Important Bird Area.

We’ve just published the results of this big review, which you can read here: Threats to Seabirds of Northern Aotearoa New Zealand

If academic-style writing isn’t your forte, I’ve condensed the main conclusions from the review below. You can also hear me chat to Kathryn Ryan about it on RNZ Nine to Noon here.

The main idea here was to identify what we do and don’t know, what research needs doing, but most importantly, what we can do now to start addressing the threats seabirds face to protect them.

Main threats to seabirds

Introduced species

Cats, rats, stoats, pigs – introduced mammals are ravaging our seabird populations. Some of our seabirds are lucky enough to breed on predator-free islands, but others are not so fortunate. With so much coastal development in our region, pet animals also come into contact with vulnerable seabirds, like little blue penguins.

Fisheries

Very little of the fishing effort in Northern New Zealand is observed – but we know from what little there is that seabirds are falling victim to baited hooks. Black petrels and Flesh-footed shearwaters are particularly at risk. Another concern is the set-net fishery, which isn’t observed at all and is the most non-selective fishing method – the risk of by-catch in this fishery is a huge problem.

Pollution

With lots of humans in our region, we make a lot of pollution. Plastic washing into the ocean is a serious concern, and the risk of an oil spill in this region could be catastrophic. Also problematic is the large amount of artificial light at night that we generate in areas that are home to nocturnal seabirds – petrels and shearwaters. It disorients them and can cause them to ‘fall-out’ of the sky, landing in residential areas, roads, and on vessels. Their chances of survival after that are slim if they’re not found and released back to sea.

Climate Change

Climate change is threatening entire ecosystems, but its hitting our seabirds hard. Increased storm events and rising sea levels threatens the breeding habitat of New Zealand fairy terns, and can cause landslips that destroys habitat for burrow-nesting seabirds. But there are other concerns – how will changing sea temperatures impact the prey seabirds feed on – the food chains on which they rely?

Disease

We know nothing about the potential for disease to impact seabirds in our region, but it is a problem identified elsewhere in the world. It’s something we really need some research on.

Direct Human Impacts

Ultimately, all of these impacts have humans as their root cause. But we also cause more direct threats to seabirds by using their habitats as recreational areas, and in some cases actively persecuting them. Remember this news story? Our native gulls are in decline, and still they are pointlessly killed.

What can we do?

We can’t fix all the problems and remove these threats to our seabirds overnight, but there are things we can do to start mitigating and minimising them.

Being mindful of seabirds and their habitats is a good beginning – to minimise the disturbance we might cause them. Keeping dogs on leash on beaches, and controlled at night if you live in a coastal area where there may be penguins nesting.

Improving their habitats is a good next step – trapping to reduce the densities of pests like rats and stoats in seabird areas, reducing our use of plastic and cleaning up coastlines, and minimising lights at night.

Ultimately we can’t do this alone. We need to push local and central government to make changes – like better observance of our fishing vessels, light restrictions on vessels moving past seabird islands, and island pest eradications – that will make bigger impacts to protect these species. And it’s not just for the seabirds, it’s for the whole ecosystem. Seabirds connect land and ocean by bringing marine nutrients to their nesting sites, enriching the land and supporting greater biodiversity. We need to protect our oceans so that seabirds can continue to be this vital link.

It’s no small task. But together, I have hope that we can begin to restore what we’ve lost.