Poznai University of Life science
Poznai University of Life science
Mikula P.,Charles University |
Hromada M.,University of the Humanities |
Hromada M.,Poznai University of Life science |
Tryjanowski P.,Poznai University of Life science
Ornis Fennica | Year: 2013
Bats (Chiroptera) and Common Swifts (Apus apus) are excellent fliers that use buildings as roosts and breeding sites in urban areas. Some predators have recently become adapted to hunting formerly unavailable prey. One such urban predator is the European Kestrel (Falco tinnunculus). We analyzed the diet and foraging behaviour of this species in Bardejov, North-Eastern Slovakia. In several observed breeding pairs, some bird began to hunt bats using novel foraging behaviour: sit-and-wait above ventilation channels of building facades where bats roosted, using ambush and perching tactics. Kestrel pairs that specialised in hunting bats also hunted Swifts. We did not find significant differences between Kestrel sexes in hunting bats and Swifts, but Kestrels preying on bats and Swifts had significantly higher breeding success than those that did not. Recently, Kestrels and their novel prey, bats and Swifts, have become endangered by rapidly-improved insulation of building facades in Central Europe. This intervention simultaneously destroys breeding and roosting places and potentially causes the collapse of urban populations of the European Kestrel.
Wasielewski O.,Poznai University of Life science |
Giejdasz K.,Poznai University of Life science |
Wojciechowicz T.,Poznai University of Life science |
Skrzypski M.,Poznai University of Life science
Apidologie | Year: 2011
Winter months are supposed to be a crucial period for the development of the reproductive system, especially ovaries, in Osmia rufa females. During 7 months of the wintering period (from September till March), the length and width of terminal oocytes and protein concentrations in ovary and fat body tissue extracts of red mason bee females, O. rufa, were studied. Our observations indicate statistically significant differences in the size of terminal oocytes for three different periods of over-wintering: September-October, November-January and February-March. Ovary growth was fast in the September-October period; it slowed down in November-January, and then increased again in February-March. Time-dependent changes were noted also in the number of oocytes and protein concentrations in ovary and fat body tissue during all wintering periods. During all winter months the number of oocytes progressively increased, but a statistically significant increase was only noticed for the periods September-October and February-March. Similarly, during the first two months (September-October) and the last three (February-April) we observed major changes in protein concentration in ovary and fat body tissue. Our results indicate that adult diapause in O. rufa varies to some extent in comparison to the other insects, probably because the the ovary is not fully inhibited during wintering, including the diapause period. These results allow a better understanding of the wintering strategies, including the diapause period, and may be useful for improving rearing methods of this economically important species. © 2011 INRA, DIB-AGIB and Springer Science+Business Media B.V.