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Reaction of Palearctic and Nearctic chickadees to sympatric and allopatric predators using feeder experiments: do regional differences in recognition of predators and determination of threat they are posing exist?
Lončík, Lukáš ; Fuchs, Roman (advisor) ; Špinka, Marek (referee)
We have examined wild palearctic and nearctic parids in their ability to recognize and assess a threat level of sympatric and allopatric predators. The study was conducted in Prague, Czech republic, on great tits (Parus major) and blue tits (Parus caeruleus) during the winter of 2013, and the following year in the city of Calgary, Canada, on black-capped chickadees (Poecile atricapillus). Three species of falcons (merlin (Falco columbarius), common kestrel (Falco tinnunculus) and american kestrel (Falco sparverius)), were chosen, two of which were sympatric and one was allopatric to the studied parid species in each area. We have also tested their reaction to nest predators magpies (eurasian magpie (Pica pica), black-billed magpie (Pica hudsonia)). Using two ground feeders in the winter time, we gave parids a choice between a feeder with either one of the three dummies of falcons, or a magpie, and a feeder with a dummy of either a hawk (the most dangerous predator of small birds) or a dove (a harmless bird of the same size as falcons). As a control we have only used sympatric species: eurasian sparrowhawk (Accipiter nisus), Cooper's hawk (Acipiter cooperii), eurasian collared dove (Streptopelia decaocto) and mourning dove (Zenaida macroura). Results from the city of Calgary did not produce any...
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Reaction of Palearctic and Nearctic chickadees to sympatric and allopatric predators using feeder experiments: do regional differences in recognition of predators and determination of threat they are posing exist?
Lončík, Lukáš ; Fuchs, Roman (advisor) ; Špinka, Marek (referee)
We have examined wild palearctic and nearctic parids in their ability to recognize and assess a threat level of sympatric and allopatric predators. The study was conducted in Prague, Czech republic, on great tits (Parus major) and blue tits (Parus caeruleus) during the winter of 2013, and the following year in the city of Calgary, Canada, on black-capped chickadees (Poecile atricapillus). Three species of falcons (merlin (Falco columbarius), common kestrel (Falco tinnunculus) and american kestrel (Falco sparverius)), were chosen, two of which were sympatric and one was allopatric to the studied parid species in each area. We have also tested their reaction to nest predators magpies (eurasian magpie (Pica pica), black-billed magpie (Pica hudsonia)). Using two ground feeders in the winter time, we gave parids a choice between a feeder with either one of the three dummies of falcons, or a magpie, and a feeder with a dummy of either a hawk (the most dangerous predator of small birds) or a dove (a harmless bird of the same size as falcons). As a control we have only used sympatric species: eurasian sparrowhawk (Accipiter nisus), Cooper's hawk (Acipiter cooperii), eurasian collared dove (Streptopelia decaocto) and mourning dove (Zenaida macroura). Results from the city of Calgary did not produce any...
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The use of amodal completion inpredators recognition: effect on risk taking
Sedláčková, Kristýna ; Fuchs, Roman (advisor) ; Nekovářová, Tereza (referee)
Amodal completion enables animals (birds, mammals, but also fish) to perceive partly occluded objects as whole. Most of the studies focusing on the occlusion phenomenon were carried out in a laboratory and were based on either operant conditioning or filial imprinting techniques. This study concentrates on behavior of untrained animals in their natural habitat. Pairwise preferential experiments were used to reveal responses of tits (the great tit, Parus major; the blue tit, Cyanistes caeruleus; the marsh tit, Poecile palustris) to two dummies placed near an experimental and an alternative feeder. The dummies used were the complete dummy of a sparrowhawk and a pigeon, and partly occluded (the lower or upper torso hidden in shrubs) and amputated (only lower or upper torso on the perch) models of sparrowhawks - 15 combinations altogether. The tits considered all variants of torsos to be predators. The great tit and the blue tit perceived the model with occluded lower torso as more dangerous than the one with amputated lower torso. Such discrimination between these torsos requires the ability of amodal completion. The great tit also confirms this ability as it regarded the complete sparrowhawk and the model with occluded lower torso as equally dangerous. In the remaining cases, the number of arrivals...
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