Investigations have also been made into the levels of industrial polychlorinated biphenyls (PCBs), following their identification as pollutants in 1966. Mercury levels, derived from both agricultural and industrial sources, have also been tracked. In addition, the contract supports a wildlife incident investigation service, which can examine the causes of unexpected mortality incidents that are not obviously related to oil pollution or to agricultural pesticides. In recent years, investigations have been made into the effects of the newest generation of rodenticides on barn owls Tyto alba. Gannet Morus bassanus eggs are regularly collected biennially from two colonies and, when available, from other sites; eggs were collected from three sites in 1998.

 

This programme is now the longest running of its kind anywhere in the world and the findings stimulate considerable interest internationally, as well as in Britain. Annual reports (like the present one) give an interim summary of results. This current report presents the results of analyses carried out on material collected in 1999. Every three years these annual results are gathered together into a more substantial report in which they are integrated with previous findings. The last report of this type covered the period up to and including 1997 (Newton et al. 1998) and the next, due in 2002, will cover material sent to Monks Wood during the period up to and including 2000. Results are published periodically in the scientific literature, and recent key papers are listed in the present report.

 

The Wildlife and Pollution contract was the subject of scientific assessment within JNCC's rolling programme of peer review in autumn 1993 and was further assessed in 1997. As a result of the last assessment, some monitoring was curtailed. Specifically kestrels Falco tinnunculus were no longer monitored for organochlorines, although CEH still collects specimens for studying other contaminants as part of its core research programme. Similarly, other species (peregrine falcon Falco peregrinus, common buzzard Buteo buteo, long-eared owl Asio otus, little owl Athene noctua, kingfisher Alcedo atthis, great-crested grebe Podiceps cristatus, and bittern Botaurus stellaris) that were received in small numbers in occasional years were also not analysed. Hence, the present report is the first not to report organochlorine and total mercury concentrations in kestrel livers and in the livers of some individuals of other miscellaneous species that were received.

 

Each section within the Wildlife and Pollution contract is summarised below. Each is dependent on the provision of material from amateur naturalists and other interested parties, and it is not always possible to obtain desired material for analysis, especially from remote areas. No major incidents were investigated in 1999.