It seems Adélie penguins - the species made famous by the animated film "Happy Feet" - are doing much better than previously thought. 

Scientists have more than doubled their estimates of the penguin population living along a 5,000-kilometer stretch of coastline in East Antarctica from around 2.4 million to nearly six million. 

The French, Australian and Japanese research team used aerial and ground surveys, tagging and resighting data and automated camera images over several breeding seasons to arrive at the new figure. 

Until recently, population estimates took only breeding pairs into account and did not look at non-breeding birds, which are harder to count because they are foraging at sea and not nesting on land, said Australian Antarctic Division seabird ecologist, Louise Emmerson in a press release. 

"Our study in East Antarctica, has shown that non-breeding Adélie penguins may be as, or more, abundant than the breeders," said Emmerson. "These birds are an important reservoir of future breeders and estimating their numbers ensures we better understand the entire population’s foraging needs."

The scientists say the research has implications for marine and terrestrial conservation, as more birds means more potential for conflict with human activities in the Southern Ocean and on the continent. For instance, it has helped to estimate the amount of krill and fish required to support the entire penguin population.  

"An estimated 193,500 tons of krill and 18,800 tons of fish are eaten during the breeding season by Adélie penguins breeding in East Antarctica," Emmerson said. The Commission for the Conservation of Antarctic Marine Living Resources will use the information to set sustainable krill fishery catch limits. 

French explorer Jules Dumont d’Urville discovered the penguin species in 1840 and named them for his wife Adéle.

While the animals are abundant, they still face dangers from climate change, as sea ice retreats and krill declines, according to environment NGO WWF.