Bokyong and I met at the Sir Peter Blake Trust office in Auckland CBD, before beginning our journey to Aotea/Great Barrier Island (GBI) at the DOC office in Warkworth. Here, we were given a general overview to the Hauraki Gulf Maritime Reserve, the island and the black petrel by Community Ranger, Michelle Jenkinson. We then met our fellow escapee, DOC Trainee Ranger, Jane Williams, and were whisked off to our awaiting boat at Sandspit Wharf. We loaded our gear onto the boat and were joined by Nikki McArthur (Wildlife Management International Ltd; WMIL), Jo Sim (DabChick NZ) and her seabird detecting dog, Rua, who would be joining us on GBI, along with a group of scientists who we would be dropping off on Hauturu/Little Barrier Island (LBI) for work on the NZ storm petrel project.
As we sped out across the Gulf it was great sitting up on the bow, being splashed by sea spray. There is nothing quite like watching seabirds as they effortlessly soar over the white caps; here they are truly in their element! We were lucky enough to get to see a few black petrels amongst them. Anchoring off LBI we transferred gear and people back and forth between the island and boat via a kayak pulley system. LBI is under strict quarantine to avoid any unwanted pests coming ashore. In the chaos we picked up Dan Birgim (WMIL) who had just done two weeks of Black Petrel monitoring on LBI and would also be joining us for the next two weeks. We then set sail for GBI, our final destination.
After a slightly bumpy ride we arrived in the pristine waters of Port Fitzroy, GBI. There DOC staff were waiting with a small dinghy to ferry the 6 of us, Rua and our gear to the island. We were then dropped off at the track start by Cara and Louise and bid farewell to Jo and Rua, who would be spending the first few nights searching other areas of the island for black petrels.
After a quick lunch, Nikki, Dan, Jane, Bokyong and I stared the 2 hour ascent to our private palace, nicknamed the rat’s nest, nestled just below the Hirakimata (Mount Hobson) summit. Following a slightly gruelling climb we arrived at the rat’s nest just before the rain set in. A much-needed cup of tea was soon in hand and our fist down time of the day gave Nikki a chance to explain a bit more about the black petrel project and WMIL’s involvement in it.
The black petrel would have once nested throughout the ranges of the North and South Islands. However, like most of New Zealand’s seabirds, their breeding range significantly declined because of introduced mammalian pests. Today the approximate 1,000 breeding pairs are only found nesting on LBI and GBI; 90% of which nest on GBI. Black petrels mate for life and once a pair has set up a burrow they will generally return to it year after year to breed. A single egg in November-January with chicks hatching in February-March and fledging between 3-4 month old in May-June. Pairs won’t relay if breeding fails. Juveniles return to the same island on which they were raised to breed at 5-7 years old. Commercial and recreational fisheries also pose a huge risk for black petrels which are often caught as by-catch. They are recognised as New Zealand’s most at-risk seabird from commercial fishing. Elizabeth (Biz) Bell of WMIL set up and has led the black petrel project since the 1990’s. The Project involves regular (generally 3 times each breeding season) monitoring of known burrows, banding any unbanded birds with a uniquely numbered metal band, searching areas for new burrows to get an idea of burrow density and occupancy outside the study areas, and night-time searching of birds in the hope of getting recaptures to shed light on juvenile and adult survival.
Thanks to the rain which continued overnight, we spent the next morning becoming familiar with the rat’s nest and getting to know our fellow hut-mates. By early afternoon it had cleared up enough to start our first round of burrow checks. I was paired with Dan, who has his level 3 banding certification for black petrels (meaning he can teach others to band) in the hope of getting to band any unbanded birds we found myself. Bokyong and Jane were teamed up with Nikki. With maps in hand we set off in search of study burrows. Our main task for the next 2 weeks would be to go to all 445 study burrows to ascertain breeding status (non-breeding, egg, chick) and if birds are breeding to identify/band both parents. Burrows being bred in would need multiple checks over the two week period to identify both parents. This is an exciting time with adults incubating eggs, brooding young chicks and the odd older chick left alone while parents forage. Generally, only one parent will be present if the pair are still incubating an egg or brooding a young chick. Parents will generally not stay throughout the day with chicks old enough to be left alone (>1 week).
Dan and I quickly found our first burrow and, after donning thick leather gloves (because these birds are at the top of the food chain and their beaks can do some damage), I eagerly stuck my hand down to meet my first black petrel. It’s huge eyes greeted me as I led it out by its beak. It was a banded bird! The band number was read and the bird weighed. We checked the burrow before putting the bird back and found a large milky-white egg.
The afternoon and the next few days went on like this in our first round of burrow checks with a range of occupants being found in burrows; from adults incubating eggs, chicks alone which let out an indignant squeak as you reached into their burrow, family reunions with a chick and both parents being found in a burrow to a pair of adults having a nice day-time burrow snuggle. The adults, most of which were banded and have returned to the same burrow year after year to breed have an array of different personalities with some hiding behind their chicks or eggs, nibbling on the finger you offer them and then calmly being led our of the burrow when you do manage to grab hold. Others would chomp down on your finger as soon as you put it within range as if excited to hear you squeal with pain and spend the whole time outside the burrow kicking and biting and generally making life difficult.
Jemma Welch
BLAKE DOC Ambassador 2016