A team of keen birders recently participated in an 11-day trip to the remote Kermadec Islands, about 800 km north-east of mainland New Zealand. Several of the species they encountered are rarely seen or photographed – in New Zealand or anywhere.
Trip organiser Scott Brooks has loaded more than 70 of his stunning images from the trip on to New Zealand Birds Online. Our Curator Vertebrates (and NZ Birds Online administrator) Colin Miskelly showcases the best of Scott’s Kermadec bird images.
What is New Zealand?
Most of us have a clear understanding of where we live. However, the physical extent of Aotearoa New Zealand is much larger than most people realise, and the limits of our international borders are still being debated with our neighbours. At the minimum, ‘New Zealand’ includes all outlying island groups administered by New Zealand, and the seas surrounding these islands out to 200 nautical mile (370 km) from their coasts.
This definition pushes the northern limit of New Zealand out until it almost touches the southern limits of Tonga.
What is a New Zealand bird?
The New Zealand bird checklist is based on the birds that occur on land or within New Zealand’s Exclusive Economic Zone, which is the 200 nautical mile limit referred to above. The outer limits of New Zealand are inaccessible to land-based birders, and we have little information on what tropical rarities occasionally cross into our northernmost waters.
It was the hope of seeing new or rarely-seen ‘New Zealand’ bird species that led to Scott and his 12 companions organising the trip.
Kermadec Islands – seabird mecca
The Kermadec Islands are a chain of volcanic islands that stretch over about 240 km from tiny L’Esperance rock in the south to the largest island (2938 ha Raoul Island) in the north. The Herald Islets off the north-east coast of Raoul Island (and Nugent Island in particular) are the northernmost landmasses in New Zealand. Raoul Island is an active volcano, and is about 1080 km north-east of Auckland.
The islands are home to millions of breeding seabirds. Until recently, many species were confined to the smallest islands in the group.
However, since rats and cats were eradicated from Raoul Island in 2002, and Pacific rats (kiore) eradicated from 278 ha Macauley Island in 2006, seabirds have been able to reclaim the Kermadec Islands in their entirety.
Most of the Kermadec Islands’ seabirds breed nowhere else in the New Zealand region. While nearly all of them occasionally reach New Zealand coastal waters, the only way to guarantee to see them is to make the pilgrimage to their breeding sites.
The most abundant species are all petrels, including black-winged petrel, white-naped petrel, Kermadec petrel, wedge-tailed shearwater, and Kermadec little shearwater.
The Kermadec petrel is a polymorphic species, meaning that it comes in a confusing array of plumages. All the images in the following gallery are of the same species.
The white-naped petrel is a boldly-marked seabird that became extinct on Raoul Island about a century ago due to the ravages of cats and rats. Fortunately it survived on Macauley Island, where it became abundant after goats were eradicated in 1970.
The smaller black-winged petrel is the most abundant bird on the Kermadec Islands (several million pairs). It is the only one of these petrels that also breeds (in small numbers) elsewhere in New Zealand.
The wedge-tailed shearwater is related to the familiar sooty shearwater (tītī or muttonbird) of southern New Zealand, but has a much lighter build and longer tail.
The two storm petrels that breed in the group are much rarer, as their small size made them particularly vulnerable to rats. Very few nests have been found for either species, but it is likely both are recovering in numbers, and perhaps recolonising former breeding sites, since the recent rat eradications.
The team estimated that they saw about 200 white-bellied storm petrels, a species which also breeds at a handful of other islands across the subtropical South Pacific. They were thrilled to get great views of a single recently-fledged Kermadec storm petrel, which must be one of New Zealand’s rarest endemic birds.
It’s not just a petrel station
In addition to the petrels, there are another seven species of seabirds known to breed on the Kermadec Island. All of these also breed on other tropical and subtropical islands in the South Pacific and northern Tasman Sea, including Norfolk Island and Lord Howe Island.
The largest is the masked booby – a tropical relative of the gannet – while the smallest is the grey noddy (or grey ternlet), a few of which reach the outer Hauraki Gulf most summers.
In addition to the grey noddy, other tropical terns breeding in the group include the sooty tern, black noddy, brown noddy, and the ethereal white tern.
The brown noddy was first discovered breeding in the Kermadec Islands in 1989. Scott and his team estimated that they saw 200 of them, indicating that they are now well established.
The best known of the seabird species breeding on the Kermadec Islands is the legendary amokura or red-tailed tropicbird. This spectacular species occasionally washes up on mainland beaches, where its long red tail streamers were and are revered taonga (treasures).
Visitors from the north
Scott and his team were particularly searching for rare vagrant birds from the north – and they weren’t disappointed. The highlight was a single collared petrel, which has its nearest breeding grounds in the Fiji archipelago.
If accepted by the Birds New Zealand Records Appraisal Committee, this will become the fourth record of this species from New Zealand waters.
Another highlight was a flock of at least 43 great frigatebirds around the Herald Islets. This is by far the largest gathering of this tropical species seen in New Zealand.
As Scott Brooks says, “It wasn’t long before these massive black prehistoric looking birds were hovering all around as, swooping down gathering things from the water, and even picking off the odd wedge-tailed shearwaters (which luckily got away). An awesome experience to witness”.
Other northern visitors included three providence petrels, nine Gould’s petrels, three red-footed boobies and a brown booby. Two of the red-footed boobies were sitting in the same tree (on Nugent Island) as New Zealand’s first record of this species just 5 years earlier.
Visitors from the south
Many species of southern seabirds were seen during the two-day voyage to the islands (from Tauranga), and on the return. These included five species of albatross that breed on islands south of New Zealand, and also a single Antarctic prion (which have their nearest breeding colony on the subantarctic Auckland Islands).
Two species from even further south were migrating Wilson’s storm petrels and a single South Polar skua. Both these species breed on the Antarctic continent.
The team also observed a few species that had migrated from the Arctic, and that rarely reach the New Zealand mainland. These included a wandering tattler on the Herald Islets, and a long-tailed skua over the Star of Bengal Bank south of the Kermadec Islands.
What were the highlights?
In Scott’s own words, the award for the ‘Best Bird of the Trip’ goes to the collared petrel, the ‘Outstanding Performance Award’ goes to the great frigatebirds, and without doubt the award for the ‘Most Dramatic Role’ goes to the Kermadec storm petrel.
Read Scott’s account of the trip to understand the drama around the storm petrel sighting.
I am very grateful to Scott Brooks for his generosity in sharing so many gorgeous images from the trip – nine of which have been selected as new master images on New Zealand Birds Online.
Thanks also to team member Brent Stephenson for his images of the collared petrel, one of which replaces his own image as the new master image for this species.
11,000 images on New Zealand Birds Online – and the Brooks family’s Big Year
Two new birds for New Zealand – Herald petrel and red-footed booby
Interesting to see reference to the Kermadec Storm Petrel. As outlined by Heads(2017), the Kermadecs support quite a number of endemics, including 68 of the 358 mollusk species, five of the 13 echinoderms, three plant species, a coastal fish, and a parakeet. These are good examples of taxa that have inhabited the active Tonga-Kermadec arc ever since its formation by surviving as a metapopulation on the individually ephemeral islands produced along the arc. The Tonga-Kermadec arc is part of the original Pacific arc that has migrated away from the Gondwana (Australia) margin into the Pacific. It is this evolutionary relationship between geology and distribution that makes the biota of these islands scientifically significant rather than a mere birding curiosity.