Use of track counts and camera traps to estimate the abundance of roe deer in North-Eastern Italy: are they effective methods?
Population density of European roe deer Capreolus capreolus was estimated in six forest areas of North-Eastern Italy through the use of different methods. The most effective method to estimate a population density is always case-dependent and, thus, varies across study areas. Particularly, drive count and vantage point count estimates (i.e. counts by hunters) have been reported to be the most effective to assess deer densities in woodlands, but they require a high volunteer human presence, which limit their feasibility. Results of count by hunters were thus compared with estimates obtained through camera trapping and track counts. Surveys were all carried out between 2014 and 2015. The three-used method provided us with comparable density results, suggesting that they all may be applied in the study area. Track-count survey was shown to be—with equal effectiveness—the cheapest method to infer roe deer density in forest areas (i.e. near 28% cheaper than camera trapping). As to our study sites, we therefore suggest that the proposal of track-count method might provide wildlife managers with a cost-effective alternative to other count methods to estimate roe deer population density. However, it is noteworthy that track-count method may also lead to lower density estimates than the drive counts; an apparent difference in the accuracy between methods needs to be considered when choosing for a certain count method.
KeywordsCapreolus capreolus Drive counts Vantage point counts Camera trapping Track counts Economic costs
We would like to thank the Friuli Venezia-Giulia Region for sharing their data, Cristina Comuzzo and hunters from the SIPS (Società Italiana Pro-Segugio- www.enci.it) project for their support with camera trapping and Yannick Fanin for his support in Doberdò del Lago Reserve. We thank CyberTracker Conservation for the software. Part of this research was carried out within the project named “L’interazione tra gli ungulati, attività cinofilia, caccia con l’uso dei cani da seguita e grandi e meso carnivori” funded by the Società Italiana Pro-Segugio- www.enci.it.
TR, CG and SF conceived the idea and collected all the data; EM helped in the paper organization and wrote part of it based on the data collected by other authors. Two anonymous reviewers kindly improved the first version of our manuscript with their comments.
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