HUSTINGS F & GANZEVLES W (1984) The Fieldfare Turdus pilaris as a breeding bird in South Limburg: numbers, distribution and some remarks on breeding biology. LIMOSA 57 (2): 37-42.

Fieldfare Turdus pilaris During this century the Fieldfare has expanded its West European breeding range in westerly direction. Since 1974 the species breeds annually in South Limburg (fig. 1). Censuses were carried out in 1975-77 and 1981-83. The counts show that the population strongly increased during that period (1975: 20-21, 1983: 343351 pairs). At present South Limburg probably harbours the majority of the Dutch breeding population. The expansion started in some strongholds in the extreme south of the study area, and now there is a tendency for filling the area between these strongholds (fig. 3). During the first years, most pairs bred in orchards and poplars near streams, but later on other habitats were chosen as well (fig. 2, 4). An increasing tendency is observed for breeding in larger colonies (fig. 5). Many Fieldfares breeding in colonies start egg laying in mid April; most solitary pairs probably breed later in the season (fig. 6). Contrary to findings abroad there is little evidence that colonies are frequently destroyed by specialised predators.

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