Breeding habitat associations and predicted distribution of an obligate tundra-breeding bird, Smith's Longspur

The condor

Teri C. Wild¹ 

关键词: Calcarius pictus;    sub-Arctic;    predictive distribution model;    climate change;    Brooks Range;    Alaska;   

DOI  :  10.1650/CONDOR-14-77.1

学科分类：动物科学

来源: Central Ornithology Publication Office

【 摘 要 】

ABSTRACT Smith's Longspur (Calcarius pictus) is a species of conservation concern which breeds in Arctic habitats that are expected to be especially vulnerable to climate change. We used bird presence and habitat data from point-transect surveys conducted at 12 sites across the Brooks Range, Alaska, 2003–2009, to identify breeding areas, describe local habitat associations, and identify suitable habitat using a predictive model of Smith's Longspur distribution. Smith's Longspurs were observed at seven sites, where they were associated with a variety of sedge–shrub habitats composed primarily of mosses, sedges, tussocks, and dwarf shrubs; erect shrubs were common but sparse. Nonmetric multidimensional scaling ordination of ground cover revealed positive associations of Smith's Longspur presence with sedges and mosses and a negative association with high cover of shrubs. To model predicted distribution, we used boosted regression trees to relate landscape variables to occurrence. Our model predicted that Sm...

【 授权许可】

CC BY