Grace lands dream project
ACCELEROMETERS, video cameras and GPS recorders are providing new insights into penguin foraging behaviour and revealing how they adapt to environmental changes.
Ecologist Grace Sutton is using the latest technology to make discoveries into the finescale foraging movements of penguins in the sub-Antarctic.
The technology has enabled the researcher to unlock the secrets to their survival in the harsh and sensitive ecosystem.
Ms Sutton is studying for her PhD with Deakin University’s Centre for Integrative Ecology.
A partnership between Deakin and the University of La Rochelle, France — supported by a Nicholas Baudin Travel Grant — has given Ms Sutton an opportunity to spend three months collecting data on macaroni penguins in the Kerguelen Islands.
After first travelling to Reunion Island, she sailed aboard a French Antarctic vessel to the sub-Antarctic islands.
Ms Sutton said penguins were the Southern Ocean’s biggest consumer group, making research into their eating habits an important priority for scientists.
The macaroni penguin population at Kerguelen Islands forms about 18 per cent of the species’ population, about 800,000 individuals.
The research has provided new information on macaroni penguin foraging ecology and gives a sense of the potential impact on fish-stock recruitment due to larval fish mortality.
The issue has potential to devastate the commercial fishing industry and other parts of the food chain.
“It has always been assumed that macaroni penguins perform deep dives to search for and capture krill and that fish comprise only a small part of their diet in the early stages of their breeding cycle,” she said.
“However, the cameras revealed that they consume a large number of larval fish during shallow dives close to the water’s surface.”
The cameras used to record the penguins’ adventures at sea are protected by a 3Dprinted waterproof housing.
They are attached to the back of a penguin with waterproof tape. Once the camera is fitted, the bird is released back to its nest and the device is re- moved when it returns.
“The devices are very lightweight and only left on the animal for a single foraging trip, to minimise stress and potential impact on the penguin’s normal foraging behaviour,” Ms Sutton said.
Part of the research in- volves examining factors influencing a penguin’s foraging success, such as the abundance of a particular kind of prey.
If a penguin happens upon a plentiful array of energetically rich prey, this will increase its intake and reduce the amount of time it spends searching for food, expending less energy in the process.
The presence of other foraging predators could lead to competition over the same prey, affecting the possibility of the penguin’s success in obtaining nourishment.
“We also need to take into account the intrinsic variables of each individual penguin, such as body condition.
“An animal in good condition would be physically stronger and able to catch more prey than those in a poorer body condition,” Ms Sutton said.
“As this is the first study to use video cameras with accelerometers, GPS and depth recorders on macaroni penguins, it’s important to do additional monitoring over multiple years to understand how this new behaviour is influenced by environmental conditions such as prey availability.”
Ms Sutton has also begun researching little and African penguins, with the aim of generating a better understanding of their foraging and other behaviour at sea.
She is due to complete her PhD in July.
“I love travelling to new places, learning new things and being among nature,” she said.
“I enjoy the challenge of interpreting and discovering new things through the data that I’ve collected. I hope to continue doing research after my PhD and am currently looking for postdoc positions.”