Hierarchical structure in bird-habitat associations can arise from hierarchical structure in environmental variables and from the scale-dependent responses of birds to habitat. Hierarchical structure in environmental variables is expected to result from interactions between variables that differ in grain size (spatial resolution) and frequency, and should occur commonly. Birds cannot accurately...

A two-dimensional hydraulic model River2D was used to investigate the significance of flow complexity on habitat preferences of brook trout Salvelinus fontinalis) in the high-gradient Staunton River in Shenandoah National Park, Virginia. Two 100-m reaches were modeled where detailed brook trout surveys 10–30-m resolution have been conducted annually since 1997. Spatial hydraulic complexity metr...

Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend...

ovis orientalis isphahanica has a restricted geographical range and is listed as vulnerable by iucn. however, there is not enough data on habitat associations of this taxon to be used as a base for conservation programmes. use of vegetation communities by isfahan mouflon in mouteh wildlife refuge was studied over a one-year period. habitat use was related to vegetation communities and habitat v...

--The habitat requirements of open nesting birds were examined in 19, five hectare, plots arranged along an altitudinal gradient in western Montana. Seven, mature forest birds were examined in detai 1. Percent shrub and low canopy cover {0.5-1.5m), mid-canopy cover {8-25m), and the number of large diameter stems {25-50 em dbh) were of major importance to this avian co11111unity. Increased avian...