Local enthusiasts boost Northland sea bird colonies
28 Jun 2019, 8:00 AM
With Oi nesting on one end and fake gannets on the other Taurawhata headland is being re-established as a hot spot for sea birds.
Helping to bring the two species back to the mainland at Tutukaka are two dedicated local bird lovers - retired but very active amateur ornithologist Hilton Ward and highly motivated year 11 Whangarei Girls High School student Dayna Davies.
Over three years of almost weekly visits to the headland the duo have become close birding buddies, often assisted by Hilton’s wife Melva and Dayna’s mum Wendy.
Taurawhata is a prominent feature on the rocky coastline about midway between Tutukaka and Matapouri. It is part of the Bowden family farm, most of which has recently been formally protected under a perpetual QEII covenant.
Oi, or grey faced petrel, were once common around the shores of New Zealand. In many places their populations were strong enough to sustain long term cultural harvesting, but were no match for introduced mammalian predators, especially stoats, rats and cats.
The Oi, sometimes called the northern muttonbird, are an oceanic seabird with a short powerful hooked beak. At sea they are graceful with a strong soaring flight, yet when they come ashore at night are clumsy, often crash landing through trees.
Their calls as they approach land are also unusual, described as a cross between a squeaky wheel and a braying donkey. They are one of the few burrowing petrels to still survive on the New Zealand mainland.
During their long breeding season Oi feed mainly in the Tasman Sea or well east of New Zealand over deeper oceanic water around the edge of the continental shelf. They often range thousands of kilometers in a few days. Both parents bring squid from afar to feed a single chick in a burrow at sites like the re-establishing Tutukaka colony.
Gannets, traditionally known as Takapu, have maintained a few strong mainland colonies but many of their smaller breeding grounds have been lost to development and predators.
The fake gannets on Taurawhata are special fibreglass models imported from the famous Audubon organisation in the United States. Carefully arranged in a make believe colony these models are accompanied by a cacophony of gannet calls coming from a solar powered, weather proofed sound system. The idea is that the models will encourage real life passing gannets to drop in and set up a new colony.
The models and sound equipment were purchased with a grant from QEII’s Stephenson Fund with the project, complete with spread sheets and detailed estimating, overseen by Dayna.
As a child, well before any predator control work had begun at Turawhata, Guy Bowden remembers clambering around most of the rocky outcrops and not coming across any active Oi burrows.
“Then one day many years later I was down there looking for seed on a special Manuka that grows on the cliffs when I found some burrows that looked like they were in use,” Guy explained.
“It was incredibly exciting to think that the predator work we had begun might be allowing the Oi to stake a claim back on the mainland. But it was also a bit scary, there was an overwhelming sense of responsibility.
“Obviously the birds had made quite a large investment in these burrows. It’s not easy to dig a burrow a metre and a half into hard clay and gnarly old tree roots. It’s not something that was done overnight, in fact looking closer some of the burrows seemed very old, probably generations old.”
So Guy began extra trapping and baiting and set up motion activated game cameras to work out what was happening. Video footage confirmed that the Oi were returning to their traditional burrows.
Concerned that they had some “trap shy” stoats and vast numbers of mice and rats, particularly in the long kikuyu covering much of Taurawhata, Guy organised, with assistance from the Northland Regional Council, for 1080 to be laid in bait stations on the property.
The Bowden family chipped in to have professional trappers intensify regular predator trapping around the re-establishing colony and it wasn’t long before the video clips showed Oi preening, mating and eventually hatching and fledging at least 14 chicks.
All was looking well in the second year and just as things were hotting up on the cliff tops Guy had a health scare and needed help.
Hilton turned up and offered to take over regular monitoring and assisting with the predator control work. He brought Dayna along, having met her at a Ngunguru School “Earth Ed” event.
But despite an increase in trapping around the headland what looked like being a 16 fledgling year for Taurawhata turned into a nightmare with all of the chicks wiped out.
Last year, however, after another round of 1080 set in bait stations plus relentless trapping, some of it targeted by the video monitoring, Guy believes the colony fledged 13 new Oi.
This season the video clips recovered each week by Hilton and Dayna capturing activity around the burrows suggests there could be even more breeding success.
Story and photos by Malcolm Pullman