Consultez les articles du Bulletin Aves !
Aves, 10/1 | 1973 | 2-18
The first aim of the study was to carry out a census of Red-backed Shrike (Lanius collurio) in Belgian Lorraine. Subsequently, it has been found interesting to combine that study with researches on ecological conditions requested by the bird in small region around Arlon. Therefore, on the one hand, we have collected all known summer data about the Red-backed Shrike from 1969 to 1972. Sixty four nesting places were censused in Belgian Lorraine. They are unequally spotted on the area, with a higher concentration at the upper part of tributary streams of the Attert, Vire and Ton. On the other hand, we have systematically investigated all possible nesting sites in a radius of 10 Km around Arlon. Thirty eight pairs were recorded. Nests are built in thorny hedges in which Single Styled Hawthorns (Crataegus monogyna) are always present. Usually situated near a path or a road, the hedge is never far away from water and is sometimes near a wood. As a rule, the main axis of the hedge is oriented North-South. Subsoil is made of marl (calcareous clay), at a contact line with a layer of grits. Adjacent landscape consists of numerous very small and various parcels. Last, we have pointed out some behavioral data from which the most interesting observation seems to be the evidence of a normal second laying. In conclusion, Red-backed Shrike is a regular breeding in Belgian Lorraine, rather well distributed over the region of Arlon. Though fluctuating from one year to another, its population looks stable and seems not to be threatened to regression in the next future. The main danger could come from restructuration schemes of parcels in agricultural areas.