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ŠUMARSKI LIST 5-6/2019 str. 17     <-- 17 -->        PDF

parameters for evaluating antlers, it is necessary to point out that antler mass and volume show the greatest correlation with the length of the beams (r=0.87; Stubbe, 1977) whilst this correlation is much smaller, for example, with specific weight, the diameter of the pedicle and the circumference of the burr. According to Stubbe (1977), a high correlation between the mass and volume of the antlers and the length of the beams was also found in red deer (r=0.91; and r=0.89 respectively).
Volmer and Herzog (1995) established that roe deer aged from 1 to 5 years have antler density of 1.61 to 1.70 g/cm3. However, the density of beams of roe deer from different habitats is from 1.57 to 1.76 g/cm3 and, according to Pis et al. (1994), from 1.60 to 1.84 g/cm3. In summarizing the results of antler density (without the skull) it may be concluded that the density of the beams does not exceed 2.00 g/cm3. That is to say, these authors expressed the specific weight as the quotient of the skull mass without the lower jaw, together with the antlers, whilst the specific weight of the antlers alone, without the skull, according to Stubbe (1967) was from 4.63 to 4.91 g/cm3. In general the specific weight of the skull bones without the antlers is much lower.
At the age when roe deer achieve the highest values of antler mass and volume, the density of the antlers is lowest, and in fact highly capital trophies are on average porous (Szederjei 1966, Pis et al. 1994). Moreover, Szederjei (1966) mentions that when evaluating roe deer through a telescope, it is best to evaluate the trophy value on the basis of volume. This is logical, because large trophies (with greater volume) seems strong when observing on a distance. Eiberle (1965, 1980) did not find a statistically significant correlation between specific weight and beam length. However, in general, specific weight decreases with age and is at its lowest in roe deer at the age of 4 years. This, in fact, indicates that the growth in antler volume in youth is much greater than the increase in mass, resulting in porous antlers. The physical development of roe deer ends at two years of life.
By measuring individual parameters of roe deer trophies, Eiberle (1980) also came to the conclusion that antler mass grows more quickly than volume, but points out that it is difficult to make a uniform rule regarding the development of antlers, because they are affected by a large number of factors. In open hunting grounds the increase in antler mass alongside the increase in body mass in roe deer is much more intense, and it has been shown that there is a positive correlation between the length of the lower jaw and the quality of the antlers, or body mass and the antler mass (Eiberle 1980)
Since the formula for evaluation of trophies should favour the elements indicating the quality of the animal, it seems that the choice of mass and volume was correct, since both of these elements account for a very large proportion of the total trophy value. Vogt (1937) and Passarge (1965) concluded that the antler mass may even be calculated from the body mass. Vogt (1937) found that the antler mass was from 1.5 to 3% of body mass, and Passarge (1965), from 1.1 to 1.3 % of body mass. Later, Passarge (1971) showed that in yearlings this percentage was only 0.4 to 0.8%.
A requirement for antler mass of 700 grams is a net body mass of about 23 kg. Although roe deer from the eastern part of the area are also known for higher values according to Vogt (1937), the upper limits for individual elements of measurement of trophies are as follows: a) Antler mass – 700 to 800* g, b) Beam length - 35 cm and c) Body mass up to 30 kg.
However, in defining the formula for evaluating trophies, the geographical characteristics of roe deer were definitely not taken into consideration. That is to say, in natural habitats with a colder climate (the northern and eastern parts of the area) the antler mass decreases with increased body mass. The reason for this is the lack of food during the growth of the antlers, limiting the growth of strong antlers (secondary gender indicator). In the same way, no close correlation was found between antler volume and body mass (Stubbe 2008).
On the other hand, according to Reichelt (1986), who analysed trophies at hunting exhibitions, the formula for evaluating roe deer antlers favours mass, since the proportion of points for beam length in roe deer is 7% (for all other wild ruminants it is a minimum of 18%), the proportion of mass is 34%, whilst the proportion of volume is 52%. Studies so far dealing with the influence of individual environmental factors on the length of beams have shown that size is influenced by population density (Pélabon et al. 1998) or climate factors (Mandarić 2011). It is hard to believe that the formula for evaluation of roe deer trophies will change, however, from an anthropocentric point of view, roe deer antlers that are attractive to the eye are in fact porous. Whether this is the result of a lack of minerals in the habitat or some other factors, is still a matter for research.
From all mentioned we can conclude that deduction of 65 or 90 g does not correspond to the real weight of the removed, denser parts of the skull. Deduction of 65 g for a