The killing of birds for examination and sampling is generally discouraged,
especially in countries such as Britain where, in addition to legal protection for
most avian species, there is a strong body of public opinion about animal issues
and also considerable confusion about what does or does not compromise welfare.
However, there are always exceptions. If birds are dying in large numbers, partic-
ularly if they appear to be in pain or distress, there may be public support for
killing them on humanitarian grounds. In some countries, pest species are culled
in large numbers—well-known examples are the control programs for Galah
CockatoosCacatua rosiecapillain Australia and Quelea Quelea queleain Africa—
and often relatively little public concern is expressed. In these and similar
instances, obtaining freshly dead specimens is usually not difficult. More often,
however, the investigator has to make use of opportunistic sampling, collecting
birds as and when they become available or relying on chance submissions.
8.1.1Terminology—definitions and explanation
Before discussing postmortemexamination and associated techniques, it is
important to define terms. Ornithologists do not always use words and phrases
relating to health, disease, and pathology in the same way as do veterinarians and
other medically trained personnel. Such differences can lead to confusion, espe-
cially in interpreting findings that are reported in literature, and some such mis-
understandings may take years to resolve (Cooper 1993b).
First and foremost, a “postmortemexamination” is synonymous with a
“necropsy” and the two terms will be used interchangeably in this chapter. The
word “autopsy” is, in English, usually reserved for the postmortemexamination of
a human being: in French and certain other languages it can be used for any
species. Other important terms that have specific meanings and are relevant to
this chapter are listed in Table 8.1. Some others appear later in the text.
8.1.2Methodology—an overview of techniques
Three main aspects of methodology relate to the examination of dead and
dying birds:
(i) the killing (euthanasia) of sick, sometimes moribund, birds;
(ii) the gross postmortemexamination of dead adult or immature birds and
of eggs;
(iii) the taking of samples from birds or eggs for laboratory examination.As was pointed out above, the killing of birds is sometimes necessary, either on
humanitarian grounds or because material is needed for investigation. Whether
Introduction| 181