Animals in Ljubljana ZOO are fed with a specific diet to a set schedule. This represents a consistent and relatively accessible food source for some species of wild birds. Consequently there is a loss of food for kept animals. This thesis intends to survey wild birds foraging on feeding grounds of brown bear (Ursus arctos), wolf (Canis lupus) and white pelican (Pelecanus onocrotalus) and survey the size of populations living in ZOO area. Between April 2015 and January 2016 we carried out three surveys of bird populations. Feeding of bear and wolf had been filmed and presence of wild birds, along with their behavior, was monitored. We conducted an experiment to determine the average amount of meat that hooded crow can consume when feeding. During feeding of pelican we documented the number of grey herons and their behavior. By observation, we determined number of specimens in the feeding area and response to food (the type and quantity of consumed food). An attempt was made to evaluate the loss to the ZOO caused by birds. During feeding of observed animals, mainly hooded crow, magpie and grey heron were spotted. During feeding of bear, hooded crows consumed a kibble, fish and fish heads. There was little conflict among crows, but they avoided the bear. During feeding of wolf, hooded crows consumed approximately 1,9 % of meat by pecking in summer observation period and 3,2 % in winter observation period. However, they managed to carry away a significant amount of rabbit carrion that was not included in this estimate. We suspect the presence of crows has also some benefits, since they feed on leftover pieces of food that would otherwise be left to rot. During feeding of pelican, only grey heron was observed. It consumed only 1,7 % of fish dedicated to pelicans.
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