HABITAT SELECTION OF NIGHT-MIGRATING PASS ERINES DURING GROUND FOG

JENNI L

L. Jenni, HABITAT SELECTION OF NIGHT-MIGRATING PASS ERINES DURING GROUND FOG, Journal fur Ornithologie, 137(4), 1996, pp. 425-434

21

TEDESCO

Article

Ornithology

Journal fur Ornithologie → ACNP

0021-8375

137

4

1996

425 - 434

ISI

0021-8375(1996)137:4<425:HSONPE>2.0.ZU;2-C

Night migrants generally terminate migration during the night or befor e sunrise and usually land in their species-specific habitats. In orde r to get insights into their behaviour during and after landing, habit at selection of small passerines was examined during ground fog in a s equence of habitats at the shores of Lake Neuchatel. On days with grou nd fog, Erithacus rubecula, Turdus merula and Sylvia atricapilla, depe nding on wood and bushes, were caught in higher relative and absolute numbers on the dune and in the reed-beds which they meet first when fl ying across the lake, than on days without ground fog. Acrocephalus sc irpaceus, a typical reed species, however, was more concentrated in th e reed-belt during ground fog than without fog. A day-migrant and a gr oup of sedentary species showed no significant differences. This indic ates that visual cues are important when selecting habitats during noc turnal landing. The diurnal distribution of captures and the fat score s of Erithacus rubecula indicate that most individuals caught in the r eed-bed and many on the dune had been migrating the previous night. Du ring the first day-light hours, Robins in the reed-bed disperse, proba bly to more appropriate habitats, irrespective of fog, while Robins th at have landed on the dune wait until fog has dissolved.