Wpływ cech populacji i środowiska na dokładność i precyzję wyników symulacji lotniczej inwentaryzacji zwierzyny

• Autorzy: Witczuk J. , Pagacz S.

Warianty tytułu

EN

Effects of population and habitat characteristics on the accuracy and precision of wildlife aerial surveys results

• Języki publikacji: PL

Abstrakty

EN

Estimation of population abundance is one of the most difficult tasks in wildlife management. In case of forest−dwelling ungulates, none of the currently available survey methods is satisfying in terms of accuracy, precision, and cost−effectiveness. Therefore, we propose a new method of ungulate monitoring based on distance sampling and using unmanned aerial vehicles equipped with thermal infrared cameras. The method is potentially more reliable and cost−effective than conventional survey techniques. It also allows for aerial surveys in the dark when animals are most active. However, the method needs to be tested before wide−scale implementation in wildlife management practice. While the effects of sampling design and effort on accuracy and precision of abundance estimates are well recognized, the importance of population and habitat characteristics is often overlooked by wildlife managers. We used simulations to assess the effects of population size, animal aggregation, and habitat−depended detection probability on the accuracy and precision of wildlife aerial survey results. We created 1000 virtual populations defined by population density (2−22 individuals/100 ha), mean group size (1−6 individuals), and probability of animal detection during surveys (proportional to canopy cover, 30−60%). Animals were distributed on a virtual study area (5000 ha) according to randomly generated density distribution. Each population was subjected to 25 simulated surveys using the same design (39 transects grouped in three 2.0×2.5 km blocks). The transects covered 12% of the entire study area. We used conventional distance sampling to estimate abundance and generalized linear models to assess the effect of each parameter on the accuracy and precision of estimates. The estimation accuracy was mostly affected by the probability of detection (β=–0.75) and, to a lesser degree, by aggregation (β=–0.25) and population size (β=0.09). Precision was influenced by the aggregation (β=0.32) and population size (β=–0.26), while detection probability had a weaker effect (β=–0.11). Observed significant differences in quality of abundance estimates derived by the same survey design, but with differing population and habitat characteristics, indicate that each survey requires an individual approach. It is impossible to formulate general recommendations, e.g. concerning flight plan or area coverage. To achieve the required level of precision, while minimizing the survey costs, it is necessary to test alternative survey designs with the aid of computer simulations.

• Wydawca: -
• Czasopismo: Sylwan
• Rocznik: 2020
• Tom: 164
• Numer: 07
• Opis fizyczny: s.560-567,rys.,bibliogr.

Twórcy

autor

Witczuk J.

• Muzeum i Instytut Zoologii Polskiej Akademii Nauk, ul. Wilcza 64, 00-679 Warszawa

autor

Pagacz S.

• Muzeum i Instytut Zoologii Polskiej Akademii Nauk, ul. Wilcza 64, 00-679 Warszawa

Bibliografia

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