Author: Dean E. Medin
Publisher:
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.
Bird Habitat Relationships Along a Great Basin Elevational Gradient
Author: Dean E. Medin
Publisher:
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.
Publisher:
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.
Bird Habitat Relationships Along a Great Basin Elevational Gradient
Research Paper RMRS
Author:
Publisher:
ISBN:
Category : Forests and forestry
Languages : en
Pages : 636
Book Description
Publisher:
ISBN:
Category : Forests and forestry
Languages : en
Pages : 636
Book Description
A 20-year Recount of Bird Populations Along a Great Basin Elevational Gradient
Author: John Woodyard
Publisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 16
Book Description
During 1981 and 1982, Dean E. Medin conducted bird censuses along an elevational gradient (5,250 to 11,400 feet) near and on Wheeler Peak of east-central Nevada. Twenty years later we conducted bird censuses on seven of his 12 plots. Data from the bristlecone pine--Pinus longaeva--plot were collected in 1981 but not published (data on file with the Great Basin National Park). Data for the remaining six plots were collected in 1982 and published. In general, all 2002 bird counts from the seven study plots recorded substantially fewer numbers of total birds and, with the exception of the bristlecone pine and alpine study plots, recorded fewer bird species as compared to Medin's counts of 1981 and 1982. Total numbers of birds counted in the 70 visits (10 census visits for seven study plots) to all study plots for 1981 and 1982 was 5,034. This compares to 1,930 for 2002, or a reduction of 3,104 birds--a 62 percent reduction. Total number of bird species sighted in 1981 and 1982 was 83 compared to 75 in 2002, or a reduction of eight. Sixty-three species of birds were common to the 1981/1982, and the 2002 censuses. Twenty species of birds were sighted in 1981 and 1982 that were not sighted in 2002, and 12 species were sighted in 2002 that were not recorded in 1981 and 1982.
Publisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 16
Book Description
During 1981 and 1982, Dean E. Medin conducted bird censuses along an elevational gradient (5,250 to 11,400 feet) near and on Wheeler Peak of east-central Nevada. Twenty years later we conducted bird censuses on seven of his 12 plots. Data from the bristlecone pine--Pinus longaeva--plot were collected in 1981 but not published (data on file with the Great Basin National Park). Data for the remaining six plots were collected in 1982 and published. In general, all 2002 bird counts from the seven study plots recorded substantially fewer numbers of total birds and, with the exception of the bristlecone pine and alpine study plots, recorded fewer bird species as compared to Medin's counts of 1981 and 1982. Total numbers of birds counted in the 70 visits (10 census visits for seven study plots) to all study plots for 1981 and 1982 was 5,034. This compares to 1,930 for 2002, or a reduction of 3,104 birds--a 62 percent reduction. Total number of bird species sighted in 1981 and 1982 was 83 compared to 75 in 2002, or a reduction of eight. Sixty-three species of birds were common to the 1981/1982, and the 2002 censuses. Twenty species of birds were sighted in 1981 and 1982 that were not sighted in 2002, and 12 species were sighted in 2002 that were not recorded in 1981 and 1982.
A 20-year Recount of Bird Populations Along a Great Basin Elevational Gradient
Bird-habitat Relationships Along a Vegetation Gradient in Desert Grasslands of the Southwest
Author: Giselle Teresa Downard
Publisher:
ISBN:
Category : Birds
Languages : en
Pages : 172
Book Description
Publisher:
ISBN:
Category : Birds
Languages : en
Pages : 172
Book Description
A 20-year Recount of Bird Populations Along a Great Basin Elevational Gradient
A 20-year Recount of Bird Populations Along a Great Basin Elevational Gradient
Birds of a Great Basin Sagebrush Habitat in East-central Nevada
Author: Dean E. Medin
Publisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 8
Book Description
Publisher:
ISBN:
Category : Bird populations
Languages : en
Pages : 8
Book Description
Optimum Timeframes for Detecting Songbird Vocalizations in the Black Hills
Author: Todd R. Mills
Publisher:
ISBN:
Category : Birdsongs
Languages : en
Pages : 392
Book Description
Birds are indicators of vegetation structure and ecological conditions. The singing activity of birds declines during late-morning periods, which can affect estimates of abundance and conclusions regarding vegetative conditions indexed by birds. Therefore, it is important to quantify periods of bird activity so biologists can plan studies. We determined hourly detections from singing males of 22 nongame bird species in ponderosa pine, quaking aspen, and grassland vegetation types in the Black Hills of South Dakota. Detections of 12 of 22 species differed among 1-hr intervals after sunrise. Detections of yellowrumped warblers, Townsend's solitaires, red-breasted nuthatches, western tanagers, and American robins decreased on count-episodes more than 4 hrs after sunrise. Detections of dusky flycatchers declined on count-episodes more than 3 hrs after sunrise and detections of black-capped chickadees were greatest during the first hour after sunrise and declined afterward. Detections of many other species from songs or calls decreased on count-episodes more than 5 hrs after sunrise. We recommend that bird counts in the Black Hills be completed within 4 hrs after sunrise so estimates of bird abundance are not affected by reduced singing among males.
Publisher:
ISBN:
Category : Birdsongs
Languages : en
Pages : 392
Book Description
Birds are indicators of vegetation structure and ecological conditions. The singing activity of birds declines during late-morning periods, which can affect estimates of abundance and conclusions regarding vegetative conditions indexed by birds. Therefore, it is important to quantify periods of bird activity so biologists can plan studies. We determined hourly detections from singing males of 22 nongame bird species in ponderosa pine, quaking aspen, and grassland vegetation types in the Black Hills of South Dakota. Detections of 12 of 22 species differed among 1-hr intervals after sunrise. Detections of yellowrumped warblers, Townsend's solitaires, red-breasted nuthatches, western tanagers, and American robins decreased on count-episodes more than 4 hrs after sunrise. Detections of dusky flycatchers declined on count-episodes more than 3 hrs after sunrise and detections of black-capped chickadees were greatest during the first hour after sunrise and declined afterward. Detections of many other species from songs or calls decreased on count-episodes more than 5 hrs after sunrise. We recommend that bird counts in the Black Hills be completed within 4 hrs after sunrise so estimates of bird abundance are not affected by reduced singing among males.