Scientists from 19 EU member states say stocks are severely depleted after decades of overfishing and a failure to ensure that enough cod of breeding age are protected.

BBC: Extinction threat to cod

"To have a bird still breeding at this age is remarkable, " she said.

BBC: Perthshire osprey 'Lady' lays first egg of season

Douglas Richardson, head of living collections for the Highland Wildlife Park, which is situated near Aviemore, said Marty and Dominika were the right age to start breeding.

BBC: Highland Wildlife Park's rare Amur tigers mating