Spatial ecology of the grey wolf in central Europe based on GPS telemetry data

Bc. Ivo Kadlec

Diplomová práce

Abstract:

The gray wolf (Canis lupus) is a territorial carnivore that spends most of its life in an area called its home range. In order to understand the wolf's life, it is essential to study the space in which it is found and to understand the factors that affect it. In this thesis, the data of six wolves that were tracked by GPS telemetry and occurred in the area of the Czech Republic and its border region were analysed. To estimate their home ranges, the thesis used both the classical method of kernel density estimation (KDE) and its modern form considering autocorrelation between the collected fixes from GPS telemetry - autocorrelated kernel density estimation (AKDE). In all cases, the KDE method underestimated the size of home ranges, as the analysed data were very detailed and the intervals between fixes were mostly 0.5 or 3 hours. Using the ΔAICc criterion, the best fitting movement model was selected and in all cases the model with autocorrelation was chosen. The average size of home ranges determined by the AKDE method is 132.318 km2 with a confidence interval of [59.521; 184.999]. The home range is not constant in time and space and can change, so the thesis goes more in detail and deals with the spatio-temporal dynamics of home ranges in the second part. The typical "change" of home ranges in wolves in Central Europe takes place at the time of pregnancy (birth of pups), in May/June, when there is a visible change and reduction in home range area, and in the winter months, when, on the contrary, the area of home ranges is the largest. The spatiotemporal dynamics of wolf home ranges is analysed by dividing the data by month and calculating monthly home ranges over the year, including calculation of the Bhattacharyya index to quantify month-by-month spatial overlap. The results of the spatial overlap of home ranges confirmed that wolves are strongly territorial and the estimated home ranges can most likely be considered as territories. The largest changes in monthly home ranges were found in May/June and then in winter. Among the wolves analysed, there was a subadult female for which natal dispersal was observed, and it appeared that the methods used to estimate home ranges can partially estimate when she left her natal territory and when it became established.

Keywords

GPS telemetry, spatial ecology, home ranges, autocorrelated kernel density estimation, R, Canis lupus

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 2. 4. 2023

Obhajoba závěrečné práce

• Obhajoba proběhla 15. 5. 2023
• Vedoucí: Ing. Vojtěch Barták, Ph.D.
• Oponent: Miloš Ježek, Ph.D.

Česká zemědělská univerzita v Praze

Fakulta životního prostředí

Magisterský studijní program:
Ochrana přírody