DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 5-6/2019 str. 15 <-- 15 --> PDF |
variability is explained by the gross mass of the skull (R2=0.680; p<0.0001 – linear function, or R2=0.699; p<0.01 – potency function). According to the intersection of the line of the mandatory deduction of 90 g for the irregular cut, and the curve of the correlation of the loss of mass due to the prescribed cut (Figure 5), the turning point for the need to cut occurs with a gross antler mass of 310 grams. Therefore it is better to cut trophies with a gross mass less than 310 grams according to the prescribed line, because they will lose up to 90 grams, whilst the trophies with a mass of over 300 g, or 305 g, should not be cut using the shallow cut, because they will lose more than 90 g, which is more than the evaluator has to deduct for the irregular cut. In our case, 4 samples with gross mass of more than 300 g would in fact lose up to 90 g in mass by cutting, whilst 16 samples, would lose much greater trophy mass than the prescribed amount (90 g) if they were cut off. Although according to the rules for evaluation of trophies, the International Council for Game and Wildlife Conservation (the CIC), when calculating the combined points of trophy value of mass and volume of the antlers, it is not permitted to use the method of multiplication of the net mass of the antlers by the coefficient 0.23, instead of weighing them on hydrostatic scales, in this country (Croatia), according to the Regulations on Methods of Evaluation of Game Trophies, the Trophy List Form, and Keeping Records of Game Trophies and Reports on Trophy Evaluation (Anonymous 2008) it is permitted, but only for roe buck trophies where the net mass of the antlers does not exceed 250 grams. The procedure for calculation is: The coefficients of the slope of the line of equalization of the trophy values obtained by using the coefficient 0.23 for correctly sawn off and intact trophies do not differ from each other, whilst the line of equalization of dependence of data obtained by using the coefficient 0.23 for the correctly cut trophies shows a slightly smaller slope (Figure 7). However, for all three methods of trophy preparation, the correlation of the data is extremely high (the coefficient of multiple determination is from 0.985 for a correctly sawn off trophy, to 1.00 for intact or shallow cut antlers; p<0.0001). If when calculating the mass and volume of a roe deer trophy the coefficient 0.23 is used, then it is better to use it for a trophy cut using the shallow cut with respect for the net mass of 250 g (or gross mass of 340 g). That is to say, if the coefficient 0.23 is used for these trophies, then 5.75 CIC points are given for the higher trophy value of the elements of mass and volume than if the coefficient 0.23 is used for an uncut skull. If the coefficient 0.23 is used for a correctly sawn-off skull a slightly higher trophy value is obtained in comparison to a skull cut using the short nose cut, and for a trophy with gross mass greater than 150 g the trophy value is lower for mass and volume together, than for a trophy sawn off using the shallow cut. Comparison of the lines using a coefficient of 0.23 between the uncut and the correctly sawn off skull shows that it is worth cutting trophies with a gross mass up to 300g using the prescribed cut (because using the coefficient 0.23 gives a higher value in evaluation of mass and volume) but for trophies with a mass greater than 300 g it is not. Further, from Figure 8 is can be seen that if the trophy is left intact, it is not worth using the coefficient 0.23, but the trophy value is established on the basis of the actual mass and volume measured, because by the correct procedure additional 6.7 CIC points are obtained. For trophies prepared using the shallow cut, it is recommended to establish the trophy value using the coefficient 0.23 because in this way a value 1.7 CIC points higher is obtained than by using the prescribed procedure (Figure 9). The same is true for |