A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Predator presence, but not food supplementation, affects forest red squirrels in winter
Tekijät: Selonen V, Varjonen R, Korpimaki E
Kustantaja: FINNISH ZOOLOGICAL BOTANICAL PUBLISHING BOARD
Julkaisuvuosi: 2016
Journal: Annales Zoologici Fennici
Tietokannassa oleva lehden nimi: ANNALES ZOOLOGICI FENNICI
Lehden akronyymi: ANN ZOOL FENN
Vuosikerta: 53
Numero: 3-4
Aloitussivu: 183
Lopetussivu: 193
Sivujen määrä: 11
ISSN: 0003-455X
eISSN: 1797-2450
DOI: https://doi.org/10.5735/086.053.0407
Verkko-osoite: http://www.annzool.net/PDF/anz53-free/anzf53-183-193-Selonen-free.pdf
Tiivistelmä
We studied the responses of red squirrels, Sciurus vulgaris, to food supplementation and avian predation risk during two winters in Finland, when the level of natural food production, spruce seeds, varied markedly. We performed an open experiment with 6 replicates in the landscape where squirrel signs were counted near a feeding station and/or active predator nest and control site. Within each site, we counted squirrel snow-tracks and feeding-signs and checked the usage of two nest-boxes. We observed that during the winter when natural food was less plentiful, red squirrel snow-tracks decreased at sites with predator. The same was observed, only less clearly, during the winter with more natural food. Food supplementation had no obvious effect. We conclude that predators have a clear effect on red squirrels in winter. Furthermore, in situations where a species is specialized in using fluctuating amounts of natural food resources, the role of artificial food supplementation may remain unclear.
We studied the responses of red squirrels, Sciurus vulgaris, to food supplementation and avian predation risk during two winters in Finland, when the level of natural food production, spruce seeds, varied markedly. We performed an open experiment with 6 replicates in the landscape where squirrel signs were counted near a feeding station and/or active predator nest and control site. Within each site, we counted squirrel snow-tracks and feeding-signs and checked the usage of two nest-boxes. We observed that during the winter when natural food was less plentiful, red squirrel snow-tracks decreased at sites with predator. The same was observed, only less clearly, during the winter with more natural food. Food supplementation had no obvious effect. We conclude that predators have a clear effect on red squirrels in winter. Furthermore, in situations where a species is specialized in using fluctuating amounts of natural food resources, the role of artificial food supplementation may remain unclear.