Every summer, about 8000 pairs of puffins arrive on the Welsh Islands of Skomer and Skokholm to breed. Formerly much more common in Southern Britain, these two islands are now two of the most important breeding grounds. They nest in underground burrows close to the cliff tops, so that the parent birds can come in quickly to avoid predation by gulls trying to relieve them of their catch. They depend on a plentiful supply of sand eels to feed their young and overfishing of this species together with warming seas has led to a decline in seabird numbers. It is important that we realise this and protect our precious marine environment.