A project to reintroduce bustard birds to the UK is using a smelly technique - collecting and studying their poo!
The bustard, the world's heaviest flying bird, was hunted to extinction in Britain in the 1800s.
Dozens of chicks have been brought over from Russia to settle on a farmyard in a secret location here.
Scientists are looking at the birds' poo to work out what they're eating - so they can put out the right food and increase the birds' survival chances.
Watch Joe's report on looking for clues in poo!