Future Of The Rockhopper Penguin
Researchers Look To The Past To Help The Future Of The Rockhopper Penguin
Researchers at the National Institute of Water and Atmospheric Research (NIWA) in Wellington are studying the diets of our rockhopper penguins to see why the penguin population is declining. David Thompson, leader of the study, said that by analysing chemicals in the feathers of penguins held in museum collections, valuable information can be gathered about their eating habits from the past 150 years.
"The penguin population at Campbell Island has declined by 90 per cent since the 1940s," said Dr Thompson.
"The negative effects of fishing are often blamed for the deaths of our seabirds, but this is not the case for the rockhopper penguin. There is no obvious link between the decline of the rockhopper penguin and fishing practice.
"The reasons for their dramatic decline remain unclear, although several ideas have been put forward. These include changes in sea temperature, which in turn have resulted in a change in food availability or abundance."
The research, an investment by the Foundation for Research, Science and Technology, is studying the penguins at their two main breeding sites in New Zealand, Campbell Island and Antipodes Island.
"As a starting point, we are testing the idea that penguin diet has changed over the last 100 years. We believe they may be eating fish which are not their first or favourite option," said Dr Thompson.
"This is a difficult question to answer because there is no dietary data from before the 1940s and nobody knows what rockhopper penguins ate when their population was large and stable."
By studying penguin feathers, the researchers have been able to find valuable information about the particular carbon and nitrogen levels which reflect what the penguins had been eating.
"Feathers trap this dietary information, and, luckily, museums hold collections of penguins dating back to the middle of the nineteenth century."
By comparing information within the feathers of both museum and contemporary rockhopper penguins, the researchers will be able to say whether there has been a change in penguin diet. They can then assess whether this occurred at the same time as the population began to decline.
"We have been collaborating with penguin workers in the south Atlantic and Indian Oceans. We hope to be able to investigate long-term changes in penguin diet at all the major breeding sites, placing this research on a truly international footing," said Dr Thompson.
For further information:
David Thompson, NIWA, Tel 04 386 0566
Communications Adviser Foundation for Research, Science and
Technology Tel 04 9177806 Mobile 025 40 60 40
Madeleine Setchell Communications Adviser Foundation for Research, Science and Technology Tel 04 9177806 Mobile 025 40 60 40 www.frst.govt.nz