At present at the international level there are several used methods for monitoring and estimation of brown bear populations. The general conception is that the assessment of the bear is much more difficult comparable with other carnivore species.
Through these actions we intend to put in practice at small scale, a set of methods used already, with the aim of presenting to the game management units and Natura 2000 site’s managers the methods with the most exact results in the Romanian natural condition.
1. Scent stations (using active smells) - the method is frequently used in North America, and is based on the principle that the carnivores are attracted by smells. In special chosen places are followed and identified the tracks in given a time frame. The method is an indicative one of the brown bear’s presence in a territory. The method will be completed with the placement of movement sensor cameras, method for population assessment without the marking of the individuals. By combining of these methods there will be obtained information regarding density of individuals, and beside this it will be created the possibility of identifying different individuals, offering information about the bears gender and age in a certain area.
2. Finnish triangles: The method is used in Finland during the winter period. It is based on the establishing of triangle shaped surfaces, materialized permanently on the field. On these surfaces there are verified with a certain frequency the tracks which go in and come outside the area, through the monitoring of the triangle’s sides. The method hasn’t been used until now in Romania.
3. Ground snow-tracking surveys (GTS) – is the method used presently in Romania, but within this project the method will be improved by the fact that there will be established permanent transects, which will be verified with a certain frequencies. Presently the method is used in winter period, without the using of transects, but the meteorological conditions permit the application of that method for maximum one month, the results being in some cases unrealistic.
4. Tetracycline - Is a marking method, using the tetracycline as bio-marker. The active substance is impregnating itself in the bones of the animal, being visible at ultra violet light. The method requires the killing of the animal before the bone analyze, but in the context that on our study areas every year are shot around 100 bears, the application of the method during 3 years would bring valuable information about the movement of some individuals. The method requires the injection of the substance from distance into the bears without their capturing. From each shot bear in the future there will be kept some bone samples, which will be analyzed. In this action there will be marked bears only from Natura 2000 sites. The method hasn’t been used in Romania before.
5. Unduplicated counts of reproductive units - Within this method there are going to be identified females with yearling cubs and it will be observed their daily moving pattern in order to identify each female’s home range. The method hasn’t been used in Romania before.
The up presented methods have been used in different areas, each of them having good and bad points. Due to the fact that in Romania can not be applied expensive methods such as aerial observation or GPS telemetry, at large scale, one of the criteria why these methods have been selected for field application is the economical one.
The processing of the obtained data in the 5 used methods will be made with the use of a statistical analyze software and GIS instruments. Also an important element will be the assessment of the bear population’s trend, being extremely important in the management measures on long term.
The best method or method’s combination which will be considered the best from technical and financial point of view will be presented to the responsible authorities for environment protection and forestry-wildlife management in order to make it officially accepted and large scale used in Romania.
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