10:50:24 AM  

Britain's sea birds are heading for their worst breeding season on record due to a decline in the small fish they eat, according to a BBC investigation.

BBC One programme Countryfile has found the fish are becoming smaller - forcing birds to work harder for a catch with less protein.

Scientists believe warmer waters have depleted plankton stocks, which form the basis of food for many such fish.

Environmentalists argue that tackling climate change is the only solution...