Eurasian Eagle-Owl (Bubo bubo) Science Article 8 abstract Eagle Owls Bubo bubo were successfully reintroduced in the Eifel (Germany) in 1974-1999. Here we analyse whether reproductive success was related to habitat characteristics and if the patterns of habitat use and reproduction changed during the population increase. Microclimatic as well as mesoclimatic conditions influenced reproductive success. […]
Category: Strigiformes
Development of chicks and predispersal behaviour of young in the Eagle Owl Bubo bubo
Eurasian Eagle-Owl (Bubo bubo) Science Article 10 abstract Little quantitative information on the development and behaviour of chicks and young is available for many species, despite the crucial importance of such data and the sensitivity of this stage in a bird’s life. For Eagle Owls Bubo bubo, despite the large amount of scientific literature on […]
First record of cooperative nesting in the Eagle Owl Bubo bubo
Eurasian Eagle-Owl (Bubo bubo) Science Article 11 abstract Monogamy appears to be the most commonmating system amongst raptors and owls. However,alternative breeding strategies have beendescribed (i.e. polygyny, polyandry and cooperativebreeding; Newton, 1979; Mikkola,1983; Del Hoyo et al., 1999; Hatchwell &Komdeur, 2000). Recent studies have shownthat co-operative breeding is much more widespreadthan had previously been thought; […]
Factors affecting the vocal behaviour of Eagle Owls Bubo bubo: effects of sex and territorial status
Eurasian Eagle-Owl (Bubo bubo) Science Article 3 abstract We performed a playback experiment in order to assess the efficiency of two methods for detecting Eagle Owls Bubo bubo and to assess factors affecting detection rates. In each experimental visit we recorded the number and sex of the responding owls, the calling rate and the corresponding […]
Clutch size and breeding success in relation to nest box size in Tengmalm’s Owl golius funereus
Boreal Owl (aegolius funereus) Science Article 2 abstract Clutch size and breeding success was related to nest-box size in 215 nests of Tengmalm’s owl in the Kauhava region, western Finland in 1966-82, In vole peak years, but not in other years, mean clutch size was positively correlated with the bottom area of the nest-box, increasing […]
Do Tengmalm’s owls see vole scent marks visible in ultraviolet light?
Boreal Owl (aegolius funereus) Science Article 3 abstract Scent markings (urine and f ces) of small mammals are visible in ultraviolet (UV) light. Diurnal kestrels, Falco tinnunculus, use them as a cue to find areas of food abundance. We studied whether vole-eating, nocturnal Tengmalm’s owls, golius funereus, can see vole scent marks using UV-vision. In […]
Experimental increase of predation risk induces breeding dispersal of Tengmalm’s owl
Boreal Owl (aegolius funereus) Science Article 4 abstract Nest predation and its avoidance are critical components of an individual’s fitness and play an important role in life history evolution. Almost all studies on this topic have been observational, and thus have not been able to separate the effects of individual quality, habitat selection and predation […]
Clutch size and breeding success of Tengmalm’s Owl golius funereus in natural cavities and nest boxes.
Boreal Owl (aegolius funereus) Science Article 1 abstract Altogether 287 nests of Tengmalm s Owl golius funereus were visited in 1960-82 in westem Finland. The-clurches were si’nificantly larger in nest-boxes than in natural cavities. The hatching percentage and number of fledglings also seemed to be higher in boxes than in natural nesting places. But the […]
The occurrence of the Barn Owl Tyto alba insacred buildings in central-eastern Poland
Barn Owl (Tyto alba) Science Article 2 abstract The occurrence of Barn Owl Tyto alba isstrongly connected with the presence ofbuildings with suitable apertures for nestingor roosting (de Bruijn 1994, Shawyer1994). In Poland this species breeds mainlyin tall sacred buildings (Kopij 1990,Kitowski 1999). The main reason for theBarn Owl population decline is loss ofsuitable breeding […]
Yungas Screech Owl (Megascops hoyi)
[order] STRIGIFORMES | [family] Strigidae | [latin] Megascops hoyi | [authority] Koenig and Straneck, 1989 | [UK] Yungas Screech Owl | [FR] Petit-duc de hoy | [DE] Hoyeule | [ES] Autillo fresco | [NL] Hoy Schreewuil Subspecies Genus Species subspecies Region Range Megascops hoyi SA s Bolivia to nw Argentina Genus The genus Megascops comprises […]