APPENDIX F: QUARRY SUSCEPTIBILITY

The program computes the probable number of pellets striking the bird, taking into account the distribution of pellets in the shot cloud and the aim errors introduced by the firer in shooting at flying quarry. It computes the depth of penetration achieved against different regions of the bird and categorises the resultant injury. The outcome is an estimate of the numbers of both bagged and shot-but-not-retrieved birds, given as a percentage of the number of shots fired.

The computations give the probable permutation of injury categories. The bagged category is well defined, but the interpretation of unretrieved quarry is less clear: some will survive almost unscathed, and at the other extreme will be quarry that dies within a few minutes from, say, internal bleeding. Unretrieved shot quarry therefore encompasses a wide scope … the program makes no attempt to assess the outcome of unretrieved quarry.

The presentation of a bird to the gun at firing is most likely to correspond to the moment of closest approach to the gun. The bird is probably already aware of the gun and so is maximising acceleration away from the gun. This implies that the spread-wing underside view is most likely. A second shot if taken at the same bird is then likely to be rear-quartering or totally tail-on. On the assumption that the first shot ought to be adequate, the spread-wing underside view is therefore most significant. However, other presentations of the quarry may occur, such as the side or back of a flushed walked-up mallard, or the quartering back view of a bird flaring into decoys, or the angled side-view of pheasant between stands (the shooting of lower birds being unsafe to fellow guns and beaters).

The program predicts the outcome for single shots fired at a common presentation of the bird, averaged over many shots, perhaps representative of a season's statistics. In practice each shot will differ, and the outcome of a day's shoot may be biased by the conditions particular to that occasion. Additionally, shooters may be able to influence the outcome of potentially unretrieved birds by exercising their experience in the follow-up shot using double-barrelled (et cetera) guns.