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| ŠUMARSKI LIST 9-10/2021 str. 31 <-- 31 --> PDF |
Thus, the development of antlers (and horns) represents the second cohort component—a qualitative one. A question is being raised, however, of which antler variable may be a reliable indicator of differences between the red deer cohorts. In bovids, a horn length was manifested as a reliable index, especially in the wild sheep, Ovis spp. (e.g., Bunnell 1978, Hik and Carey 2000, Festa‐Bianchet et al. 2004, Loehr et al. 2007, Hengeveld and Festa‐Bianchet 2011). The research results in this paper indicate that it might be a trophy value. It might be so, however, only if one compares the cohorts evaluated in an identical trophy evaluation system, because the evaluation procedures differ (CIC, SCI, and Rowland Ward). According to Mysterud et al. (2005), a tine number may also be a cohort quality indicator, being positively connected with the meteorological conditions (snow intensity) during hibernal months—the lower the snow depth, the higher the number of tines during a summer following that winter. Nonetheless, this index is not utilizable in the juvenile head age class (e.g., aged two to five years), for the number of tines is then still relatively small (and is, as a rule, increased on the crown, whereas the first three tines (brow, bay and tray tines) are relatively permanent (Raesfeld and Reulecke 1988). The implementation of weight of dry antlers has a disadvantage of its own, because it is only measured in the CIC evaluation system, but a skull processing method upon evaluation is not standardized, since a skull may be weighed freshly processed, dry, and complete, with a smaller or larger maxilla part dissected. A skull dissection type thereby entails certain deductions (Hromas et al. 2008). Additionally, since the antler mass measurement has two components—a branch mass and a skull mass—, it is difficultly applicable to the branches shed. The length variables are also unfavorable, because the fractures of the brow and of the tray tines, or the fractures of a main beam, may occur. It therefore appears that circumferences may be the most adequate variables. According to Ullrey (1982) and Rasmussen (1985), a variability in the white‐tailed deer (Odocoileus virginianus) feedstuff quality has been manifested solely in a branch diameter modification, while the other antler variables have remained unchanged. What is more, a white‐tailed deer’s trophy quality is possible to be predicted by a branch diameter as early as in the yearling age (Severinghaus et al. 1950). Besides, a circuferences share in the overall trophy value averagely amounts to 42.4% even in the CIC evaluation system (Paljug 2018), comprising almost a half of the grade. Contrary to North American–Scandinavian approach of wild ungulate management, in the Central European approach, supplemental feeding is practiced (Adamič 1990). Therefore a cohort effect should be reduced. However, this impact is occasionally even comprehended contrarily by the researchers, as a compensation growth may occur in certain species. It is a phenomenon in which the populations in worse habitat conditions, despite an initial slower antler or horn growth, may compensate the shortcoming at a later age during a lifetime (see Rughetti and Festa‐Bianchet 2010). Certain scientists (e.g., Sibbald et al. 1993) quote that a compensation growth in the red deer |