Researchers say a recent survey using satellite mapping technology shows there are nearly twice as many emperor penguins in Antarctica than previously thought.
Scientists from the United States, Australia and Britain say the high-resolution satellite imagery helped them count 595,000 emperor penguins in Antarctica. Previous estimates had placed between 270,000 and 350,000 birds on the South Pole continent.
The scientists say using high-resolution imagery allowed them to efficiently and safely estimate an entire penguin population with little impact on the Antarctic environment. They describe the penguin colonies as notoriously difficult to study because their habitats often are located in areas inaccessible to humans where temperatures can plunge to minus-50 degrees Celsius.
The researchers say the satellite census results is a key benchmark for monitoring the impact of environmental change on emperor penguin populations. Study lead co-author, geographer Peter Fretwell of the British Antarctic Survey, also notes this is the first comprehensive census of an animal species taken from space.
The scientists say current findings suggest colonies of emperor penguins in Antarctica are vulnerable to the effects of climate change. But because satellite technology makes taking a regular continent-wide census easy, cost-effective, and eco-friendly, the researchers say they can now better track the impact of global warming on this iconic bird species.
Ground-based head counts and aerial photography also were used in the study, which is published in the journal, PLoS One.
The scientific collaboration includes researchers from the British Antarctic Survey; the Australian Antarctic Division; the University of Minnesota and the Scripps Institution of Oceanography - both in the United States.