Partial puller
Under Part pullers refers to migratory birds , where the population in winter in part on bird migration takes part and moves into the south, but partially in the breeding area remains (as resident birds ) or only slightly changed their home (such as stroke Birds ).
Most Central European birds are considered to be partial migrants: In Germany, this includes around 80 percent of all birds. A well-known partial migrant is, for example, the chaffinch , in which only the female moves south in autumn while the male stays behind. Also Goldammer , Blackcap , Robin , Star , Stieglitz and Zilpzalp be allocated to the Sub pullers.
Due to changes in the climate, more and more migratory bird species seem to be part of the migrants recently. The Swiss Ornithological Institute in Sempach describes the long-term biological benefit of partial pulling as follows:
“If a harsh winter kills many of the individuals remaining in the breeding area, the migrating conspecifics have an advantage. When the winter is mild, the resident birds survive better and by the time the migratory birds arrive they have already occupied the best territories; in this case the resident birds have an advantage. With the partial migration behavior, the birds react not only to the seasonally changing living conditions, such as the typical migratory birds, but also to the different winter conditions from year to year. "
See also
Individual evidence
- ↑ Swiss Ornithological Institute Sempach : Teilzieher.