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Article
Olav Hogstad, AuteurWillow Tits Poecile montanus maintain yearlong territories defended by a male and female mated pair. Outside the breeding season the adult pair lives together with two to four unrelated first-year Willow Tits that have settled after a post-natal[...]
Article
Olav Hogstad, Auteur ; Vidar Selås, Auteur ; Sverre Kobro, AuteurIn a subalpine birch forest in Central Norway, the breeding population of fieldfare Turdus pilaris varied from 3 to 63 pairs per km2 during 1966-2000. For the period 1971-1995, the breeding density was negatively related to the number of days wi[...]
Article
Flock composition, agonistic behaviour and body condition of wintering Bullfinches Pyrrhula pyrrhula
Olav Hogstad, AuteurDuring October-April of 1989-2003 1 made observations on size and sexual composition of Bullfinch Pyrrhula pyrrhula flocks (ringed and unringed birds), recorded interactions between members and estimated the body condition of birds observed in a[...]
Article
Per Gustav Thingstad, Auteur ; Olav Hogstad, Auteur ; James D. M. Speed, AuteurMany European-breeding bird species wintering south of the Sahel region in Africa have been reported to be in decline since the 1970s. However, most studies focus on conditions local to the breeding sites as determinants of population change, de[...]
Article
Olav Hogstad, AuteurThe foraging patterns and time spent on vigilance behaviour by Willow Tits (Poecile montanus) were studied under varying weather conditions in a subalpine forest in central Norway during the winters of 2009-2013. The birds adjusted their microha[...]
