Bird Ecology and Conservation A Handbook of Techniques

(Tina Sui) #1

a whole range of tests and analyses, in addition to weighing and detailed measuring
(see later). It can be time consuming. There is a place for such detailed work—for
instance, when birds of a rare or threatened species are involved—but often it is not
feasible for the avian biologist or veterinarian to carry out a lengthy examination on
each bird that is presented.
Apostmortemexamination form, designed to be comprehensive, is given in
Appendix I.
Such a comprehensive examination involves a whole range of investigations.
It may be best carried out by a team of people but, however, this is often not
feasible, especially in the field.
An abbreviated postmortemexamination protocol, which usually proves suc-
cessful for preliminary investigation, is given below:



  1. On reception of the specimen, record the history and give the bird a reference
    number—always good practice and an essential precaution (to facilitate
    “chain of custody”) if legal action is possible.

  2. Examine the bird externally (including beak, buccal cavity, auditory canal,
    preen gland, and cloaca)—record (and quantify) any parasites, lesions, or
    abnormalities. Comment on plumage and molt, using a standard system—
    for example, that advocated by the British Trust for Ornithology (Ginn and
    Melville 1983).

  3. Weigh and record standard measurements such as wing chord (carpus),
    tarsus, culmen, combined head and bill length and sternum (see also
    Chapter 4). A bird’s bodyweight (mass) is of limited value without a mea-
    surement of linear dimensions.

  4. Open the bird from the ventral surface by lifting or removing the sternum—
    examine superficial internal organs (see Figure 8.1). Record any lesions or
    abnormalities.

  5. Remove and set aside heart, liver and gastrointestinal tract (ligate oesoph-
    agus and rectum to prevent spillage of contents) and examine deeper inter-
    nal organs (see Figure 8.2). Record any lesions or abnormalities.

  6. Fix in buffered formalin (10%) small portions of lung, liver, kidney plus
    any organ or tissue showing an abnormality (see Table 8.5).

  7. Open portions of intestine and look with naked eye or hand lens for food,
    other material (e.g. pellets), lesions and parasites. Examination is facilitat-
    ed if the material is placed in a Petri dish with a little saline. Save any para-
    sites and make an effort to quantify them, for example, by estimating the
    proportion of the intestine examined and counting the number of para-
    sites seen.


188 |Information from dead and dying birds

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