Experts from the bird charity RSPB say some of the UK's most impressive seabirds could be disappearing from England's coastline.
They say climate change is to blame - the birds need fish for their food, and the fish are staying in colder seas further north of Britain.
To work out what's really happening, researchers are starting a massive count at one of Britain's most important homes to seabirds - Bempton Cliffs in East Yorkshire.
Bempton Cliffs is the biggest mainland colony for birds in England. Around 200,000 seabirds flock there, but the experts are seeing a decline in numbers of several species including the puffin.
Watch Joe's report to find out more.