Sergey Dereliev

Very large breeding range: SW/SC Europe, Africa, S Asia, Oceania, S part of N America and C and S America (BirdLife International 2020). Mostly resident. Absent at high latitudes and altitudes, and in deserts (BirdLife International 2020).

Season of assessment

B

Population trendIncreasing
Population size
(min-max, best estimate)		147000-184000,164000
Red List categoryLC
Franks, S., Fiedler, W., Arizaga, J., Jiguet, F., Nikolov, B., van der Jeugd, Ambrosini, R, Aizpurua, O., Bairlein, F., Clark, J., Fattorini, N, Hammond, M., Higgins, D, Levering, H., Skellorn, W., Spina, F, Thorup, K. Walker, J., Woodward, I. and Baillie, S.R. (1) (2022) Online Atlas of the movements of European bird populations. https://migrationatlas.org EURING/CMS (1) Principal investigator
Map

Overall Connectivity for Western Cattle Egret

Resident in Europe. Long-distance movements are exceptional; a bird ringed in SW Europe recovered in S Sweden; a bird from E Europe recovered in Kenya (this is, in addition, the only movement to C Africa for a bird ringed in Europe). Graphics show, therefore, dispersal patterns rather than true migrations (Sarasa et al. 1997).

Recoveries by Condition for Western Cattle Egret

Most recoveries in SW Europe-NW Africa due to birds found dead, with more or less similar proportions between those dead by shot and those found sick/wounded. An also remarkable proportion of recoveries is associated to unknown causes, but most of these might be due to birds found dead. In N Italy, however, a proportionally higher proportion of the recoveries are due to birds seen alive. Probably this is linked with the fact that the colonization of this region was more recent as compared to SW Europe, and the use of colour-rings in newer projects tends to be more generalized.

Annual Movements for Western Cattle Egret

The different nature of all the dispersal movements (post-breeding, natal, maybe breeding dispersal as well) occurring within the same geographical area adds difficulty to establish clear patterns for the annual movements. Recoveries outside the chief ringing sites occur mostly from Sep to Apr, so dispersal or birds from their breeding quarters to non-breeding quarters may be in Aug-Sep, with a return to the breeding colonies in late-winter or spring, probably well before Apr.

Connectivity by Month by Region for Western Cattle Egret

In SW Europe, egrets ringed in SW Iberia disperse mostly to SW Iberia-NW Africa. Recoveries in NW Africa mostly from Sep to Apr, reflecting post-breeding dispersal. Recoveries obtained in late-spring or summer elsewhere could reflect natal dispersal from surveyed colonies. This dispersal is random, within a distance of normally less than 500 km. Birds ringed in E Iberia constitute a well differentiated population, dispersing mostly along the coast from E Iberia to S France, with some recoveries in E Morocco. No recoveries of birds of C-S Europe (N Italy) outside this region. Monthly dispersal pattern rather similar to that observed for the SW European population. Mean dispersal distances of ca. 200 km, without variations between age classes.

Juan Arizaga

References

Statistics Map
N records N individuals N recoveries
Mapped data*
Total available data
*Mapped data include only distant (>= 50 km) recoveries
References Map
BirdLife International2020 . Species factsheet: Bubulcus ibis. Downloaded from http://www.birdlife.org on 05/08/2020
Sarasa, C.G., Garrido, J.R., Bartolomé, J., Igual, J.M., Fernández-Cruz, M.1997 . Movimientos poblacionales y tasa de mortalidad de la garcilla bueyera (Bubulcus ibis ibis, L. 1758) en la península ibérica. Actas de las XII Jornadas Ornitológicas Españolas, Almerimar (El Ejido)

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