Author: Publisher:
ISBN:
Category : Birds
Languages : en
Pages : 424
Book Description
Bird-habitat Relationships on Southeastern Forest Lands
Author: Bird-habitat Relationships on Southeastern Forest Lands
Author: Paul B. HamelBird-habitat Relationships on Southeastern Forest Lands
Author: Bird-habitat Associations on Southeastern Forest Lands
Author: Harry E. LeGrand (Jr.)Publisher:
ISBN:
Category : Birds
Languages : en
Pages : 552
Book Description
Repeatability of Riparian Vegetation Sampling Methods
Author: Publisher:
ISBN:
Category : Riparian ecology
Languages : en
Pages : 104
Book Description
Tests were conducted to evaluate variability among observers for riparian vegetation data collection methods and data reduction techniques. The methods are used as part of a largescale monitoring program designed to detect changes in riparian resource conditions on Federal lands. Methods were evaluated using agreement matrices, the Bray-Curtis dissimilarity metric, the coefficient of variation, the percentage of total variability attributed to observers, and estimates of the number of sites needed to detect change. Community type (CT) cover data differed substantially among the six to seven observers that sampled the same sites. The mean within-site similarity in the vegetation data ranged from 40 to 65 percent. Converting CT data to ratings (bank stability, successional, and wetlands ratings) resulted in better repeatability, with coefficients of variation ranging from 6 to 13 percent and a percentage of variability attributed to observers of 16 to 44 percent. Sample size estimates for the ratings generated from CT cover data ranged from 56 to 224 sites to detect a change of 10 percent between two populations. The woody species regeneration method was imprecise. The effective ground cover method was quite precise with a coefficient of variation of two, but had so little variability among sites that statistically significant change in this attribute would not be expected. In general, reducing the CTs to ratings increased precision because of the elimination of differences among observers that were not important from the perspective of the rating. Studies that seek to detect change at a single site would need to take into account the observer variability described here. Studies that seek to detect differences between populations of sites could detect relatively large changes with these methods and ratings. Small differences among populations would be difficult to detect with a high degree of confidence, unless hundreds of sites were sampled.
Determination of Habitat Requirements for Birds in Subburan Areas
Author: Jack Ward ThomasPublisher:
ISBN:
Category : Birds
Languages : en
Pages : 24
Book Description
Assessment of Nongame Bird Habitat Using Forest Survey Data
Author: Renee O'BrienBird Habitat Relationships Along a Great Basin Elevational Gradient
Author: Dean E. MedinPublisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 28
Book Description
Bird censuses were taken on 11 study plots along an elevational gradient ranging from 5,250 to 11,400 feet. Each plot represented a different vegetative type or zone: shadscale, shadscale-Wyoming big sagebrush, Wyoming big sagebrush, Wyoming big sagebrush-pinyon/juniper, pinyon/juniper, pinyon/juniper-mountain big sagebrush, mountain big sagebrush, mountain big sagebrush-mixed conifer, mixed conifer, mixed conifer-alpine, and alpine. Eighty-nine bird species were observed. The total number of birds and bird species followed a skewed bell-shaped distribution. Some birds were quite narrow in their choice of vegetative zones while others showed very little selectivity. Both total number of individual birds and bird species appeared to reach highest values in study plots with a substantial component of mountain big sagebrush.
Working with Partners for Bird Conservation
Author: Population Trends and Habitat Occurrence of Forest Birds on Southern National Forests, 1992-2004
Author: Publisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 268
Book Description
S2We determined population trends and habitat occurrences for bird species in 14 national forests located in the Southern Region from 1992-2004. We estimated population trends for 144 species within: 14 national forests, 10 physiographic areas, and in the Southern Region as a whole. Habitat occurrences were estimated for 114 species based on 13 forest types and four successional stages. We discussed results for 48 species of management concern along with information compiled on conservation status and the U.S. Geological Surveys (USGS) Breeding Bird Survey population trend estimates. There was evidence that populations increased for 42 species and decreased for 38 species on national forests in the Southern Region as a whole. Trends for many species varied widely across physiographic areas and national forests. Most species were found across a variety of habitats, though associations with particular forest types and structural conditions were often apparent. S3.