Contrôles par Condition for Effraie des clochers

Currently protected species in Europe. Most encounters have been obtained since late 1980s. The bulk of encounters come from the breeding season (Jun-Jul) – ca. 43%, mainly juveniles have been ringed over time. W, C & NW Europe hold almost all (ca. 98% combined) of the encounters.

The encounters based on dead birds decreased over time – from 78% pre-1960 to 59% after 1991, while those based on alive birds –increased (from 19 to 40% respectively). The latter is mostly due to ringing encounters, incl. nestbox ringing which largely increased from 2% in 1961-90 to 21% after 1991. Co-existence with people produced a variety of recovery condition categories related to human activities, traffic being among the currently important negative factors (22% of all cases).

Annual Movements for Effraie des clochers

Although long-distance movements in different directions have been recorded in siblings from several nests in Czech Republic (Poprach 2010), the general diversity of dispersal directions can hardly outline possible “dispersal divide” in E part of C Europe.

Juveniles from the C & W European population are encountered during their dispersal mostly between Nov and Feb wintering in W, SW & SE Europe and even SW Russia. Some birds are encountered away from their natal places as early as Sep and as late as Apr-May.

S German population has been shown to exhibit different dispersal distances, big proportion of birds moving more than 100 km (Bairlein 1985).

Very few ringing data from S Europe, one of the species’s strongholds on the continent. The bulk of data is obtained in Germany, the Low Countries, and UK.

Connectivité par mois par région pour Effraie des clochers

n general, dispersal movements in juveniles are several times longer compared to the movements of adult birds. Juveniles from the second or late broods move faster and fly shorter distances in contrast to the first brood young (Poprach 2010).

Post-breeding dispersal in juveniles start in late summer and could last until late winter, being encountered close to their natal sites or comparatively further away. Some birds are encountered away from their natal sites as late as mid- to late spring.

Suitable habitats in certain places (Equipa Atlas 2018) and some geographical obstacles can lead to concentration of juveniles during their dispersal (Poprach 2010).

Although the sample size of distant recoveries (>=50 km) is large, most of the long-distance movements are less than 300-500 km from the place of ringing (exceptionally over 1000 km).