Antipodean wandering albatross chick atop Hapeka on Pitt Island
By Dave Houston
For 5 years Kenny Dix was DOC’s ranger in New Zealand’s most remote community – Pitt Island. Situated 25km south of Chatham Island, the 6,000 ha Pitt Island is home to around 30 people – and one pair of Antipodean wandering albatross.
Now working on the “big smoke” of Chatham Island, Kenny recently took the opportunity to return to Pitt to band the wandering albatross chick atop Hakepa, one of the islands high points. This is the sixth Antipodean wandering albatross chick to be raised on Pitt Island and the fouth for the Hapeka pair. Taking almost a full year to raise, this chick will hopefully fledge in January and commence wandering the Southern Ocean. It may be up to 10 years before the chick settles down and breeds for the first time.
As the name suggests, the primary home of the Antipodean wandering albatross are the Antipodes Islands, some 700km to the south. Having visited the Antipodes myself, I can see why Hakepa’s windswept plateau, tussock and fern vegetation and magnificent views seem like home to the albatross.
Kenny with one of the proud albatross parents
Another pair of albatross at the Southern end of Pitt produced a chick two years ago, however failed to return this year to breed. We’re hoping that they might show up next year so than Kenny can keep up his banding skills.
Mid-winter opportunity to work on Chatham petrel burrows
In early July each year a small group of DOC workers head out to Rangatira or South East Island in the Chatham’s to undertake end of season work on the Chatham petrel burrows. This year we decided to give Chatham Island school children an opportunity to join us and experience the magic of Rangatira.
Rangatira or South East Island
We were joined by Year 11 Correspondence School students Harriet Graydon and Mia Foley, both of Pitt Island, along with Chatham Islander Jacob Hill, a Year 12 student at St Bedes College, for the 4-day trip.
After completing quarantine procedures designed to keep the islands pest-free, we caught an early morning fishing-boat ride from the main island to Pitt, to pick up Mia and Harriet. After a brief stop and exchange of mail and supplies, we departed for the forty minute trip to Rangatira.
Landing on Rangatira
No jetty means a bow landing on the rock platform and a frantic passing ashore of the buckets containing our food and gear, but the team handled it flawlessly.
As soon as we were ashore we bumped into our first special species, the shore plover. Once abundant around the coasts of New Zealand, this plucky little shorebird was eradicated by rats and survived only on Rangatira. Fortunately, it has now been returned to several mainland sites.
Chatham Island black robin
While hauling the buckets up to the hut we bumped into our next special resident – the black robin. With around 200 birds, Rangatira is the stronghold for the species and over the next few days we got to see quite a few as they jumped out of the forest at us in anticipation of a mealworm handout.
After settling in we fitted everyone out with petrel boards – special footwear designed to prevent us collapsing seabird burrows as we walked around the island. We then set off on our main task, checking 250 burrows of the endangered Chatham Island petrel.
After checking that this years chicks had successfully fledged (and unfortunately a few didn’t), we did a bit of housekeeping and then put a barricade in front of the entrance to stop other seabirds taking up residence while the petrels are away over the winter.
Mia, Harriet and Jacob checking a Chatham petrel burrow
While wandering around the forest for a few days we got the opportunity to see more island residents – including the Chatham Island species of snipe, parakeets, tui, tomtit, warbler and skink.
On our first night we hoped to introduce the visitors to the many seabirds and abundant invertebrates that call the island home. Unfortunately, the great weather and full moon kept all the seabirds at sea so we had to be content listening to blue penguins braying in the forest.
Fancy footwear: Petrel boards reduce damage to the many seabird burrows in the forest floor
All too soon it was time to pack up, lug the gear back to the landing and await the arrival of our ride. Our skipper Glen King treated us to the scenic route on the way home, travelling around the bottom and up the western side of Pitt Island, taking in views of Mangere and Little Mangere Islands on the way as well as taking us into an impressive sea cave.
Harriet, Mia and Jacob enjoying the view from the summit of Rangatira. Pitt Island in background
Mia and Harriet’s families were waiting on the wharf at Flowerpot when we arrived, glad to see their kids home safe and just a bit jealous of the experience. Jacob had to endure another hour-long crossing of Pitt Strait before he could head home, but the experience can’t have been to bad as he wants to come back when we open up the petrel burrows again in November. I think he’ll have some competition, as the girls want to go too.
Jacob and Harriet enjoying the trip home along with Ranger Juzah Zammit-Ross
The recent hatching of a Chatham petrel chick in the Sweetwater Conservation Covenant on Chatham Island is another significant step in the long road to recovery for one of the world’s rarest seabirds.
Probably once abundant throughout the Chatham Islands, human exploitation, habitat destruction and introduced predators saw the species restricted to Rangatira Island by the time of its discovery in 1892.
A Chatham petrel chick tucked up in its down duvet
Until 1961 farming activity on Rangatira resulted in the petrels being confined to small forest patches, where they competed for burrows with the similarly sized broad-billed prion. Nesting at different times of the year, many petrel chicks were ousted from their burrows by returning prions. By 1990 the Chatham petrel population was estimated to be around 1,000 birds and heavily outnumbered by some 600,000 broad-billed prions.
Studies found that while adult Chatham petrel survival was high, less than 50% of pairs were managing to fledge a chick, placing the population in peril. So, finding a way to deter prions from entering Chatham petrel burrows was a priority.
The competition: a broad-billed prion outside its burrow
Natural burrows converted into ‘state houses’
Natural burrows were converted into wooden ‘state houses’ with plastic pipe entrances, to aid inspection of the contents, and efforts were made to dissuade prions from using them by removing any found within and relocating some distance away. This required frequent nightly inspections of the petrel burrows and numerous DOC staff and volunteers will have memories of the nightly burrow rounds, clumping around the forest with ungainly petrel-boards attached to their footwear to avoid crushing the numerous seabird burrows. It was futile.
Lincoln University researchers finally came up with a simple solution – stretching a piece of neoprene wetsuit material over the entrance of the burrow pipe and cutting a slot just large enough for a petrel to squeeze through. It has proved remarkably effective, the petrel ‘homeowner’ tolerates the inconvenience of a tight squeeze, but prospecting prions are deterred by it. This, along with barricades erected while the petrels are away over the winter has increased nest success to around 90%.
A Chatham petrel squeezing through the anti-prion flap into its burrow
The relative abundance of Chatham petrel chicks has since allowed for the next phase of recovery, the creation of new colonies on Pitt and Chatham Islands.
200 chicks were translocated to new homes in the predator-proof Elizabeth Ellen Preece Conservation Covenant (aka Caravan Bush) on Pitt Island between 2002 and 2005. Hand-fed until ready to fledge, the chicks remembered Caravan Bush as their new home and some returned after two or three years at sea with the first pair breeding in 2005.
Rangatira Island (left) and Caravan Bush (right) on Pitt Island
Return of Chatham petrel to “Sweetwater”
Once the success of the Pitt Island translocation was evident work started on the return of Chatham petrel to “Sweetwater” on Chatham Island in 2008.
Ranger Antje Leseberg checking the band on an adult Chatham petrel
In partnership with the Chatham Island Taiko Trust another 200 Chatham petrel chicks were moved over 4 years to nest boxes within a 4ha predator-proof enclosure built by the Trust. As at Caravan Bush, petrel sounds played over loudspeakers encouraged returning petrels to land at the site.
The first indication of success at Sweetwater was seen last autumn when a pair of petrels were seen in a burrow. After wintering off the South American coast, the pair have returned to Sweetwater and laid an egg in February.
Taiko Trust members were delighted to find a chick present during burrow checks in early March. All going well this chick should fledge in May and spend 2-3 years at sea before returning to Sweetwater. By then it should have more company, as four more burrows show signs of activity, surely signalling the sweet smell of success.