After searching tawaki in Tamatea / Doubtful Sound for five days, we have some good but also some slightly worrying news.
The good news is, that we recorded a total of 203 nests on 16 different islands in the fjord. Considering that there are supposed to be more than 700 islands in the Breaksea/Dusky fjord complex, we might have barely scratched the surface of the question about the total tawaki population numbers in Tamatea. Considering that the official numbers for the fjord (dating back to surveys in the 1990s) is only 9 nests, there are a lot more penguins than anyone would have thought.
Some of these islands are unsuitable for tawaki. Not because there wouldn’t be adequate breeding habitat, but because of the flourishing fur seal population in the fjord. Some of the islands are literally overrun by fur seals, especially pups and lactating mothers. The pups are small enough to cuddle up with a penguin in their burrow. Something Myrene Otis actually directly witnessed and documented. This likely makes for a rather uncomfortable breeding experience.
However, on other tawaki islands that were free of fur seals, we found some other worrying signs.
During our searches we came across quite a few tawaki nests, that were neatly prepared with fresh sticks and leaves for this year’s breeding season, but unoccupied. This generally means, the male penguin had returned and got the nest ready to impress his partner upon her return. Only she never showed up – most likely because she did not survive the winter migration.
Now, one could think that this may happen especially considering that we are entering the third year of a strong La Niña which is known to have negative effects on New Zealand penguins. If that were the case, we would have expected to see similar patterns in Doubtful and Breaksea Sound. But we didn’t which potentially points at a localized effect, an effect that only affects tawaki in Dusky Sound.
It is too early to speculate about what may be going on in Dusky. But at any rate, it means that we have our work cut out for the coming years.
Figure out if something’s wrong in Dusky. And what’s wrong.