Scientists have come up with an innovative scheme to weigh up the survival chances of threatened penguins.
Special scales have been built to allow experts to gain vital information about the feeding habits of the Adelie penguin.
Three sets have been disguised and strategically placed on the routes popular with the birds at a colony in the Antarctic. They are triggered when the penguins waddle over them.
Weighing the birds gives scientists an indication of the amount of food they have eaten, which is crucial for finding out how the species is adapting to habitat changes.