| lead poisoning and parasitism in a flock of mute swans (cygnus olor) in scotland. | increased mortality in a flock of non-breeding mute swans (cygnus olor) on a scottish loch was investigated. postmortem examinations were carried out on eight adult and six immature swans. the commonest cause of death, found in eight birds, was lead poisoning associated with the ingestion of large lead fishing weights. heavy parasitic burdens were found in five immature birds, involving combinations of the gizzard worm amidostomum species, the thornyheaded worms polymorphus minutus and profilico ... | 1998 | 9460217 |