Naslov
EXTINCTION PROBABILITY OF BROWN BEAR POPULATION (Ursus arctos L.) IN CROATIA

Autori
Skorin, Teuta ; Huber, Đuro ; Legović, Tarzan

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
ECEM '07 Conference proceedings / Solidoro, Cosimo - Trst, 2007, 496-496

Skup
European Conference on Ecological modelling 07

Mjesto i datum
Trst, Italija, 27.11.2007. - 30.11.2007

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
brown bear; Croatia; Ursus arctos; VORTEX; population viability analysis; extinction; management

Sažetak
We performed the Population Viability Analysis (PVA) for the brown bear (Ursus arctos) in Croatia using VORTEX, a generic individual–based model. A number of scenarios were simulated in order to determine the extinction probability of bear population, because it is (i) a trophy game species, (ii) classified as endangered species and (iii) protected by the Croatian Law on Nature Protection. We tested the effectiveness of implemented brown bear management policy, especially the cull quota. The procedure involved different management options and a broad range of parameter values to reveal the processes which critically influence the population dynamics. Most of the data used originate from past researches on brown bear population in Croatia, while some parameter values had to be guessed. Existing estimates of population size range between 400 and 1000 individuals. For the population of 400, extinction probability is above 95% with every proposed and examined hunting quota. For the population of 600 individuals and hunting quota of 80 bears yearly, the extinction probability remains above 95%. However, reducing the quota to 70 bears/y, as planned in 2005 and 2006, leads to significant decrease of extinction probability which then equals only 7, 4%. This was the first attempt to use PVA for bear management in Croatia. We identied critical, and unknown data which determine the outcomes of PVA: the total population size and hunting quota have the most influence on population dynamics. Thus we propose quota reduction to 70 individuals until the actual population size is determined.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA