Feral donkey Equus asinus populations on the Karpaz peninsula, Cyprus
Numerous researchers have documented the adverse effects of feral donkeys Equus asinus introduced to semi-arid ecosystems. With the release of feral donkeys and potential increasing populations in natural habitats in northern Cyprus, there is concern for negative impacts on vegetation and native species. In the north of the island, there has been only one published study of feral donkey populations, and population estimators were relatively subjective. We estimated feral donkey populations on the Karpaz Peninsula using line transect surveys and quantitative distance sampling estimators. We stratified the sampling by using 11 sample units within the study area. We evaluated potential biases associated with habitat, topography, and perpendicular distance from the transect line and found that these variables did not bias donkey detections during our surveys. Using program DISTANCE, we found that a hazard rate cosine model was the best model that described our distance data based on model selection criterion (Akaike’s Information Criteria adjusted for small sample bias). Estimated effective strip width was 280.19 m and detection probability was 0.47 with this model. Estimated donkey density was 6.7 donkeys/km2, and estimated total abundance was 800 donkeys for the entire 132.5 km2 study area. Of 95 donkey groups detected: 16% were detected in agricultural habitats with flat topography, 9% were detected in agricultural habitats with sloped topography, 24% were detected in shrub/forest habitats with flat topography, and 51% were detected in shrub/forest habitats with sloped topography. Of 102 behavioral observations recorded (multiple behaviors were detected in groups), frequencies of behaviors were 1% bedded, 70% standing, 22% grazing, 6% moving, and 2% other. Our estimated donkey population density in the Karpaz Peninsula was >2 times densities reported in arid regions of the United States and Australia, but slightly lower than earlier density estimates reported for the Karpaz region. These estimates of feral donkey populations in the Karpaz Peninsula provide a quantitative baseline from which to make population management decisions.
KeywordsAbundance estimation Cyprus Density estimation Distance sampling Equus asinus Feral donkeys Karpaz Peninsula Line transect
A large number of people assisted with the field surveys, including students at Lefke European University, Near East University, Eastern Mediterranean University, and Girne American University. Other volunteer participants in the surveys included members of the Biologists Society, Women Organisation KAYAD, and Anglo Turkish Society. We thank Mr Hasan Karaokcu and Mr Haluk Dogandor for their support. We thank SID -Lefkosa Chapter for creating an awareness of this issue. Maps and GPS used in the survey supplied by the Karpaz Peninsula Mapping office, the Karpaz Peninsula Environmental Protection Office director and personel made great contribution to the survey. Major funding for the research was provided by Turkish Embassy (mainland Turkish Republic), the the Karpaz Peninsula Hunting Association, and Warnell School of Forest Resources of the University of Georgia.
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