Dieldrin poisoning and botulism in Australian pelicans (Pelecanus conspicillatus).

Autopsies and laboratory examinations of material from 24 Australian pelicans found sick or dead in southern coastal Queensland in 1977 to 1979 revealed dieldrin poisoning in 8 from the Brisbane region and botulism in 8 from Brisbane, Bundaberg and Gladstone. In those diagnosed as dieldrin poisoning, brain and liver samples contained 12.1 to 27.4 and 34.0 to 48.1 mg/kg dieldrin respectively. All of these birds were emaciated, 2 had convulsed and 1 had muscle tremors. Low and probably insignificant residues of DDE were detected in many birds. Type C botulism was confirmed in 4 of the 6 birds tested with specific antiserums. A large number of parasites including mites, lice, nematodes, cestodes, trematodes, coccidia and Sarcocystis sp were found but were thought to have had only a limited effect on the health of these birds.