There’s a lot to learn from St Kilda’s little penguins
The St Kilda little penguins live close to the action of a busy, major city. That makes the penguin colony unique, as few if any other colonies are known to be located in such an urbanised environment. The penguins are not just charming neighbours, they also help scientists understand the impact of changes in our climate.
Little penguins forage for food at sea but breed on land. That makes them excellent climate change indicators for both the marine and land environments.
- Penguins were first spotted at St Kilda in 1974, when there were just a few breeding pairs.
- Severe drought and high temperatures during 2006-2009 are thought to have contributed to a lower birth rate in comparison to Phillip Island.
- The global population of penguins is stable but decreasing where there is no conservation action in place.
Research conducted with Phillip Island Nature Parks (PINP), looked at how the St Kilda penguins adapt their foraging habits to deal with changes in climate. This work will help bolster the management of the penguins
The results showed that penguins change their hunting habits between drought and normal years, adapting their feeding strategy according to water flows from the Yarra River.
The Yarra provides lots of small anchovies for the penguins. In drought years the penguins concentrate their feeding closer to the river mouth to take advantage of a boom in fish staying closer to the river mouth where the nutrients are concentrated because the flow of water from the river to the bay is reduced.
In contrast, when there is more water flowing from the Yarra River, the penguins range more widely in the bay to follow the dispersed fish.
The penguin’s feeding flexibility is critical to their survival throughout the year. However, researchers found that, despite their ability to modify how far they might travel seeking food and their ability to modify their diet, there are also changes in their breeding success, signalling that the continued monitoring of where, when and how the penguins feed is central to their sound management .
Understanding the success of the colony at St Kilda is of vital importance.
The full paper can be read here:
Environmental variability drives shifts in the foraging behaviour and reproductive success of an inshore seabird