APPENDIX H: ASSESSMENT OF QUARRY CATEGORISED REGIONS

A male mallard (Anas platyrhynchos) weighing 1.23kg (average male = 1.216kg), 54cm length and 84cm span was X-ray'd and physically examined to determine the areas and depths of the regions categorised as in Appendix G.

Enhanced image of an X-ray'd mallard (includes embedded pellets) showing the 17 regions of susceptibility.

The measurements obtained are recorded in the quarry datafile Mallard.QDF as shown in Appendix J. It was then suggested that for other waterfowl (Anatidae) the similarity of bodyform would be amenable to scaling. This was tested by examination of a male Greylag Goose (Anser anser) weighing 3.63kg (average male = 3.793kg), 85cm length and 144cm span. As assumed, the presented areas were found to scale with weight to the power two-thirds, and the tissue thicknesses with the cube root of weight. There was no data on which to base the level of protection afforded by feathers and skin (see Appendix I): in the supplied datafiles this is assumed to be proportional to bird weight, though this needs to be investigated. Similarly for flying speed … this is assumed to vary with the cube root of weight. The supplied wildfowl quarry datafiles are thus related as follows:

The results of this scaling are incorporated in the Teal.QDF and Canada.QDF datafiles.