Consultez les articles du Bulletin Aves !
Aves, 10/3 | 1973 | 171-181
Joiris, C., Lauwereys, M. & Vercruysse, A.
A series of 12 small mammals (Clethrionomys glareolus, Microtus arvalis, Apodemus sylvaticus) and 10 House Sparrows (Passer domesticus) were preleved at one place in Belgium, as representing typical preys for raptors. They were analysed in order to determine their contamination with organochlorine residues. The results are discussed as follows : a. The contamination of these mainly herbivorous animals is clearly lower than the contamination previously found in birds of prey; b. There is a clear difference in the contamination of the mammals and of the Sparrow. The mammals are contaminated with lindane and heptachlor-epoxyde (on the average : 0.265 ppm), but not with DDT (with the exception of one exemplar). THe Sparrow, on the contrary, is mainly contaminated with residues of the DDT-group (0.146 ppm) and with some heptachlor-epoxyde (0.026 ppm). Differences in food-habits probably can explain those differences in contamination; c. There is no general rule to explain the different contaminations of the different tissues; d. The conclusion is that the differences found here could explain the differences in contamination previously found between the bird-eating raptors on one hand, and the raptors easting mailnly mammals, on the other.