Skeletal deformities and mortality in grey herons (Ardea cinerea) at Besthorpe heronry, Nottinghamshire.

Dead and sick grey heron chicks with multiple fractures of the leg and wing bones and/or bone deformities have been reported at Besthorpe Nature Reserve heronry in north Nottinghamshire since 1996. Forty-five grey heron carcases were examined, 35 from the Besthorpe colony and 10 from other colonies where bone disease was not known to occur. On the basis of the results of radiological studies, postmortem examinations, peripheral quantitative computed tomography scanning and four-point bending tests, it was concluded that the skeletal abnormalities were probably due to metabolic bone disease.