Bird numbers grow despite unsettled weather

It has been a challenging season for bird monitoring due to the wet weather. This has meant that when the monitoring teams have been out in the field they have been very focused on getting the work done.

Takahē

The takahē nested early this season. Both pairs successfully hatched a chick each in October. The chicks have been growing fast and are now getting their colours. Thanks to the rain the ground is softer, so they have all been able to supplement their mainly grass-based diet with a feast of worms and grubs.

The chicks, now almost the same size as their parents, have become inquisitive and brave. They are now a regular delight for the visitors to the Island. You are most likely to see the takahē in their family groups around the lighthouse or southern end of Tiritiri Matangi, and at the northern end of the Island. If you are lucky enough to see the takahē, remember to give them lots of space.

Hihi/stitchbird

The hihi have been keeping the team busy. The 74 females on the Island have made 117 breeding attempts so far (including successes, failures and current attempts). Of these, 56 have been successful and there are 153 fledglings spreading their wings and learning how to be a hihi.

A few nests were lost in the early stages, likely due to the wet and windy weather, forcing females to try to balance their time between brooding and looking for food.

We have come to the tail end of the first nests, including those who are on replacements as their first nesting attempt failed. There are currently 31 females on their second nests with either eggs or chicks, with more getting ready. Some females are already laying eggs in the second nest box we provide in their territory before the chicks have even left the first nest.

The hihi females have some eager beavers amongst them. These females built so fast that they went from a completely empty box to a fully-lined nest with one or two eggs in just four days! One female has already raised her second nest and produced seven fledglings so far. We are hoping for a third nesting attempt from her, and hope the other females attempt a second nest. Maybe this will beat the record of 252 fledglings in a single season.

With the wet weather causing a few ferry cancellations, we still managed to have at least one member of the team on the Island at a time. As a result, we managed to band 171 chicks.

Titipounamu/rifleman

All indications are that titipounamu numbers are healthy, with many noisy families evident. So far this season, around 75 pairs have been confirmed.

In 13 days, around Christmas/New Year, 66 titipounamu were caught – 46 were new birds and 20 retraps. Although neither of the 10-year-old males from last season has been seen recently, we now have one 10-year-old female who successfully bred again this season.

Kōkako

There are 22 pairs on Tiritiri Matangi this season, with another possible pair not confirmed. Most of the first nesting attempts failed due either to the weather or predation. However, most pairs are nesting again and by January 10 we recorded three pairs with one fledgling each. They were Te Rae and Chatters on December 28, followed on January 6 by Discovery and Sarang, and a new young couple, Oran and Haar, who were successful in their first breeding attempt.

Another five pairs now have a chick or chicks of various ages who will hopefully fledge over the next few weeks. Most of the remaining pairs are incubating. It is frustrating that Aquarius (and her partner Rakataura) have chosen once again to nest over the cliff which we cannot access. Her previous attempts in this location have failed due to predation so perhaps this time will be different.

Another young couple, Wai Ata and Awenga, set up a territory next to Rehu and Noel where Wai Ata cheekily built her nest very close to Rehu’s nest. This nest was not successful. Joy and Honesty have also moved in next to Honey and Rimu, which has led to much sing song from Rimu and Honey who are not impressed. We believe Joy has attempted to nest as she disappeared for about three weeks. We did not discover the nest and it must have failed as the pair have recently been seen together again.

Phantom has recovered from her leg injury and nested again, but the second nest was unsuccessful.

There are quite a few single birds, mostly young females, moving around the Island and this has been unsettling for our established pairs who have spent much time chasing them away.

Kākāriki

Kākāriki tend to start nesting later than most other species. The nest boxes were first occupied around mid-November. By mid-January there were 12 boxes in use with at least 74 eggs laid. Six of the clutches had hatched, producing around 33 chicks, the oldest of which are expected to fledge in late January.

Seabirds

Unfortunately, only one of our 22 diving petrel nest boxes has been used this year so there is little to report on breeding success. Catching adults on the surface was very successful with 130 new birds banded and 113 retrapped birds which had been banded in earlier years. The retraps included four of the 39 birds first banded in 2013.

It is too early to say how well our surfacenesting seabirds are doing but we seem to have around 60 nesting pairs of whitefronted terns. If they succeed in fledging chicks this will be one of their more successful seasons. This year some of them appear to be nesting on the reef near the wharf, a change from their more usual sites on the eastern coast.

Kororā/Little penguin

Last year, three of the wooden nest boxes along Hobbs Beach Track were used without success. This season has been better with six boxes used, as well as the three display boxes. Nine pairs had 10 nests and 20 eggs were laid.

Fourteen eggs hatched and seven chicks fledged – a reasonable success rate of 0.78 chicks fledged per pair. Three nests failed at egg stage and one at the chick stage.

This season we began to give the birds an individual transponder tag, like those used for our hihi and for cats and dogs. This will allow us to follow the long-term survival and productivity of individuals in the colony and greatly add to our understanding of how well the kororā are coping with a changing environment.

Unusual sightings

“Chaz”, the New Zealand dotterel who hatched at Hobbs Beach in 2015 (and who bears a flag with the letters CHZ), was seen at Big Manly beach, associating with other dotterels, on December 16. She (we believe she’s a she) has been seen from time to time over the years, quite often at Shakespear Park, but there has been no evidence yet of her having attempted to breed.

On January 7, two fork-tailed (Pacific) swifts were seen on the Island. Apparently this is a first for Tiritiri Matangi as previously only white-throated needletail swifts have been recorded.

On January 24 a whitespeckled sea hare, about 20cm long, (at left) was spotted near the wharf. Sea hares are a type of sea slug which feed on algae.