The work on little penguins around Wellington continues, now that most of the nesting pairs have one or two chicks to feed.
This week Te Papa scientists and helpers from various disciplines on the Te Papa staff have been putting out loggers on the chick-rearing penguins, both in Evan’s Bay and Day’s Bay.
Our previous work showed that the incubating penguins were exploiting a range of habitats across Wellington coastal areas. Some penguins used the Wellington harbour areas exclusively. Others fed outside the bay with several foraging trips to Fitzroy Bay and Palliser Bay.
During chick rearing, there are tremendous energetic demands on the adult penguins, as they need to bring food regularly to their growing chicks. In many of the Wellington harbour nests, adults are managing to raise 2 chicks at one time. This suggests that food supply for these birds is good, at least this season. Birds are visiting the chicks regularly, possibly daily or every 2 days.
The first track recovered from a chick-rearing bird (above, blue), tracked from Evans bay showed that it travelled to the waters of the Wellington Harbour mouth twice in the 3 days the logger was deployed. This was a period of strong westerly winds and large swells, so we’re not sure whether it would have left the harbour in calmer conditions. But certainly the harbour mouth area, as well as the Evans Bay and wider Wellington Harbour appear to be important foraging zones for the penguin tracked, whose track is shown here.
Transmitters attached are the same GPS (data-logging) variety used in incubation tracking, and are attached to the back feathers of the birds using waterproof tape, along with a dob of glue which adheres to the feathers and provides extra attachment strength for the loggers. At the time we attach the loggers, we weigh the birds and measure the beak to determine whether the bird is male (larger) or female (shorter beaks).
We’ll continue to update the blog over the next few weeks with our findings, and look forward to your comments and questions.