|
|
Nest defence and predator recognition by Arctic tern \kur{(Sterna paradisaea)}
ŠPIČKA, Jan
In the presented work, I describe the behaviour of Arctic terns (Sterna paradisaea) toward predator species that differ in the threat they represent to them and to their nests. I presented textile dummies of great black-backed gull (Larus marinus), peregrine falcon (Falco peregrinus), common raven (Corvus corax) and common eider (Somateria mollissima), piece of wood as a harmless stimulus, and human intruder in sitting position near the tern nests. Experiments were conducted on the Varanger peninsula in Norway. The tern behaviour was recorded and analysed to see any dummy species related differences.
|
|
| |
|
|
Antipredatory behaviour of Red-backed Shrike: the role of sign stimuli in a predator recognition
Součková, Tereza ; Fuchs, Roman (advisor) ; Hořák, David (referee)
This thesis summarizes findings on a recognition and categorization of different sorts of stimuli at birds, it deals with predator recognition in the Red-backed Shrike (Lanius collurio) in its practical part. The aim of my study was to examine if Red-backed Shrikes follow by sign stimuli or colour of stimulus during the predator recognition. I performed my research by means of experiments with dummies, I have observed antipredatory reactions of Red-backed Shrikes on various types of dummies which differ in the presence or absence of features of raptor or in the different coloration. I concluded according to Shrikes' reactions that during the predator recognition the information on sign stimuli playes the principal role, but only this information alone is not fully sufficient. Antipredatory behaviour of the Red-backed Shrike was also influenced by sex of bird apart from type of dummy, males were more active during the nest defence than females.
|
|
|
Antipredatory behaviour of Red-backed Shrike: the role of sign stimuli in a predator recognition
Součková, Tereza ; Fuchs, Roman (advisor) ; Hořák, David (referee)
This thesis summarizes findings on a recognition and categorization of different sorts of stimuli at birds, it deals with predator recognition in the Red-backed Shrike (Lanius collurio) in its practical part. The aim of my study was to examine if Red-backed Shrikes follow by sign stimuli or colour of stimulus during the predator recognition. I performed my research by means of experiments with dummies, I have observed antipredatory reactions of Red-backed Shrikes on various types of dummies which differ in the presence or absence of features of raptor or in the different coloration. I concluded according to Shrikes' reactions that during the predator recognition the information on sign stimuli playes the principal role, but only this information alone is not fully sufficient. Antipredatory behaviour of the Red-backed Shrike was also influenced by sex of bird apart from type of dummy, males were more active during the nest defence than females.
|
|
|
Role znaků a geonů v rozpoznávání predátorů netrénovanými ptáky: obrana hnízda
NOVÁKOVÁ, Nela
I examined two main hypotheses proposed for the object recognition: Particulate feature theory and recognition by components using methods of behavioural ecology, namely nest defence. We tested reactions of Red-backed shrike (Lanius collurio) to dummies of Common kestrel (Falco tinnunculus) with scrambled body parts (head above, in the middle and at the bottom). Our result suggested that birds don't recognize the kestrel in the dummies with inappropriately placed head. Therefore, our results support rather the theory recognition by components.
|
|
|
How the red-backed shrike (Lanius collurio) recognizes enemies
NĚMEC, Michal
This study investigates two questions about anti-predator behaviour of the red-backed shrike. 1) Is the red-backed shrike able to assess the differing dangers represented by various types or species of predators? 2) How does the red-backed shrike recognize the predator? We found, that the red-backed shrike (Lanius collurio) adjusts its anti-predator behaviour by assessing the potential threat to themselves from different predator species and by assessing the chance of a successful attack. Further, we found that the presence of general raptor salient features is absolutely necessary for proper categorisation of the intruder as a predator, whereas the natural species-specific colouration in itself is an insufficient cue.
|
|
| |
guest ::
