It has been established that some interspecific hybrids among ducks and geese (Anatidae) strongly resemble one parent or even another species altogether, thus causing problems in field-identification. An extreme case in Britain is the hybrid Pochard Aythya ferina x Tufted Duck Aythya fuligula which can be very difficult to distinguish in the field from the American Lesser Scaup Aythya affinis (Per

...

Stay at the forefront of British birding by taking out a subscription to British Birds.

Subscribe Now