Filters: Tags: Extirpation (X)
5 results (79ms)|
Filters
Date Range
Extensions Types
Contacts
Categories Tag Types
|
Conclusions: Habitat changes resulting from timber harvest have altered the predator–prey balance leading to asymmetric predation affecting the survivial rates of endangered mountain caribou Thresholds/Learnings: As young forest stands increase in proportion to old forests, caribou population densities and survival rates decline as they become increasingly vulnerable to predation and extripation. Synopsis: Timber harvesting in areas of Mountain Caribou habitat have created landscapes of early seral forests. Such habitat changes have altered the predator–prey balance resulting in asymmetric predation in which predators are maintained by alternative prey (i.e. apparent competition). This study estimates survival...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: British Columbia,
Caribou,
Natural cover amount,
Predation,
Woodland Caribou,
Conclusions: Caribou subpopulation persistence and landscape occupancy depends highly on the degree of forest cover, cover type, and distance from human presence. Thresholds/Learnings: Synopsis: This study evaluates factors influencing the persistence and landscape occupancy of caribou subpopulations in southern British Columbia. Data from 235 radio-collared caribou across 13 subpopulations were used to derive a landscape occupancy index. The index was analyzed against 33 landscape variables including, land cover, terrain, climate, and human influence. At the metapopulation level, the persistence of subpopulations correlated with the extent of wet climate conditions and the distribution of old forests and alpine...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: British Columbia,
Columbia Mountains/Northern Rockies,
Extirpation,
Forest,
Fragmentation,
Aim: Greater sage-grouse (Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction. Location: Sagebrush biome of the western USA. Methods: Logistic regression was used to assess persistence and extirpation of greater sage-grouse range based on landscape conditions measured by human population (density and population change), vegetation (percentage of sagebrush habitat), roads (density of and distance to roads), agriculture (cropland, farmland and cattle density), climate (number of severe and extreme droughts) and range periphery....
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Centrocercus urophasianus,
Diversity and Distributions,
distribution,
extirpation,
greater sage-grouse,
These data describe the date, time (night vs. day), observer, and air temperature of each amphibian occupancy survey conducted in coastal dune drainages from 2014 through 2016. Survey-specific covariates explain patterns in detection probabilities among surveys, thereby reducing bias in occupancy models and improving future surveys.
Categories: Data;
Types: Citation;
Tags: California,
Great Beach,
Point Reyes National Seashore,
amphibian,
coastal dune,
The long decline of the eastern migratory population of monarch butterflies (Danaus plexippus) appears to have abated in recent years and the population now persists at a much-reduced abundance. Stochastic variation in abundance typical of monarch butterflies, and other insects, places this population at heightened risk of quasi-extinction, a level of abundance below which recovery of the migratory behavior is uncertain. These data and results provide insight into the near-term status and trajectory of the eastern migratory population of monarch butterflies. Within the stationarymonarchdata.csv, overwinter[ha] are annual monarch butterfly overwinter area occupied estimates as provided by World Wildlife Fund-Mexico...
|
|
