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See detailDémographie du martin pêcheur (Alcedo atthis): incidences climatiques sur le succès reproducteur
Libois, Roland ULg

in Gerfaut (Le) = Giervalk (De) (1994), 84

It is well known that the Kingfisher populations decrease dramatically after a sever winter. The recovery depends on the climatic conditions of the next reproductive seasons. In order to understand the ... [more ▼]

It is well known that the Kingfisher populations decrease dramatically after a sever winter. The recovery depends on the climatic conditions of the next reproductive seasons. In order to understand the mechanism involved in this climatic influence, the fate of more than 500 broods was studied between 1985 and 1993. The study area comprises the river Meuse from Vireux (F,08) downstreams to Huy (B Liège) and the lower part of its main tributaries. The first egg laying date was determined for each brood, eggs were counted, pulli ringed at nest and the adults controlled and ringed when possible. Our main conclusions are i : the beginning of the first clutch is correlated with the thermic conditions of March. ii : the clutches are not synchronised, even on a same watercourse. iii : the egg probuction and the hatching success don't show clear variations between years abd habitat types (river, ponds and small streams) or depending on the clutch rank. iv : the fledged young production depends on how much broods are raised by the different pairs. v : the probability a pair is attempting a thrid brood is function of how early the first clutch is layed, the age of the male (older males settle earlier and are more productive), the habitat quality and the weather conditions (rain, temperature) in May. [less ▲]

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See detailMoineaux domestiques et Moineaux espagnols, Passer domesticus et P. hispaniolensis, dans l’ouest algérien : aperçu des variations régionales dans la morphologie externe
Metzmacher, Maxime ULg

in Gerfaut (Le) = Giervalk (De) (1986), 76

Results of a comparative geographic analysis of 3 dimensional characters (in males) and of plumage (in both sexes) in sympatric populations of the House sparrow, Passer domesticus, and of the Spanish ... [more ▼]

Results of a comparative geographic analysis of 3 dimensional characters (in males) and of plumage (in both sexes) in sympatric populations of the House sparrow, Passer domesticus, and of the Spanish sparrow, Passer hispaniolensis, collected in February and March in western Algeria. Tail length shows a significant geographic variation in males of both sparrows, and wing length in males of Spanish sparrow. Coincidence of geographical variation in feather dimensions of the two taxa suggests a parallelism, owing to common environmental pressures. Plumage colour of the House sparrow varies geographically : on that account the specimens collected in Bechar oasis differed from those examined in northern localities. [less ▲]

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See detailMoineaux domestiques et Moineaux espagnols, Passer domesticus et P. hispaniolensis, dans une région de l’ouest algérien : analyse comparative de leur morphologie externe
Metzmacher, Maxime ULg

in Gerfaut (Le) = Giervalk (De) (1986), 76

This note compares 5 external morphological characters of sparrows, Passer domesticus and Passer hispaniolensis, from one locality of western Algeria. Age variations, in the Spanish sparrow, and sexual ... [more ▼]

This note compares 5 external morphological characters of sparrows, Passer domesticus and Passer hispaniolensis, from one locality of western Algeria. Age variations, in the Spanish sparrow, and sexual variations, in the both sparrows, are also examined. These analysis show the following results : - Spanish sparrow average larger than House sparrow in bill size, but average smaller in tail length ; - in both sparrows, the strongest correlation is between wing length and tail length ; - at a multivariate level, results of component analysis are such that two relatively distinct clusters of male are present. These results support my conclusions that Orania possess two populations of sparrows (Metzmacher, 1984). However, this technique give only a weak discrimination of the females phenotypes ; - in males of Spanish sparrow, there is a correlation between color of the heel feathers and cranial ossification. During a part of the year, this color can be used for age determination ; - adult Spanish sparrow of both sexes average larger than first-year in tail length ; - in both sparrows, males average larger than females in wing length, but the sexes do not differ in bill size ; - in Spanish sparrow, sexual size dimorphism seems to increase with age. The possible signification of the principal morphological variations is discussed. [less ▲]

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See detailVariations géographiques de la figure finale du chant du Pinson des arbres, Fringilla c. coelebs L.
Metzmacher, Maxime ULg; Mairy, François

in Gerfaut (Le) = Giervalk (De) (1972), 62

The song of the Chaffinch (Fringilla coelebs) was recorded in several regions of Belgium by methods adapted to local ecological conditions. The variation of the final figure of the song was investigated ... [more ▼]

The song of the Chaffinch (Fringilla coelebs) was recorded in several regions of Belgium by methods adapted to local ecological conditions. The variation of the final figure of the song was investigated. A comparison between the various samples indicated the existence of local dialectal areas and several regional dialectal areas. Complementary recordings in intermediate areas showed the continuity of the High-Belgium dialectal area, and the existence of a transition zone between the regional dialectal areas of High-Belgium and Middle-Belgium. The occurrence of the dialectal areas raises several question about the distribution of the variants, their origin and their function. [less ▲]

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