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Keyword: population dynamics

Influences of spatial and temporal variation on fish-habitat relationships defined by regression quantiles

Publications Posted on: July 24, 2006
We used regression quantiles to model potentially limiting relationships between the standing crop of cutthroat trout Oncorhynchus clarki and measures of stream channel morphology. Regression quantile models indicated that variation in fish density was inversely related to the width:depth ratio of streams but not to stream width or depth alone.

Prairie chicken populations of the Sheyenne Delta in North Dakota, 1961-1987

Publications Posted on: July 24, 2006
Prairie chickens (Tympanuchus cupido pinnatus) were first censused on the Sheyenne Grasslands in 1961. The population was extremely low in the 1960's, gradually increased in the 1970's, and reached a peak of 410 in 1980.

Network-scale spatial and temporal variation in Chinook salmon (Oncorhynchus tshawytscha) redd distributions: patterns inferred from spatially continuous replicate surveys

Publications Posted on: July 06, 2006
Spatially continuous sampling designs, when temporally replicated, provide analytical flexibility and are unmatched in their ability to provide a dynamic system view. We have compiled such a data set by georeferencing the network-scale distribution of Chinook salmon (Oncorhynchus tshawytscha) redds across a large wilderness basin (7330 km2) in central Idaho for 9 years (1995–2003).

Effects of the Chytrid fungus on the Tarahumara frog (Rana tarahumarae) in Arizona and Sonora, Mexico

Publications Posted on: June 12, 2006
We conducted histological analyses on museum specimens collected 1975-1999 from 10 sites in Arizona and Sonora to test for the pathogenic chytrid fungus (Batrachochytrium dendrobatidis) in ranid frogs, focusing on the Tarahumara frog (Rana tarahumarae). During 1981-2000, frogs displaying disease signs were found in the field, and all of these we tested were infected with the chytrid pathogen.

Changes in the Pincate Reserve ecosystems: Invasion of non-native plants

Publications Posted on: June 09, 2006
Over the years, humans have modified the Sonoran Desert by introducing invasive plants that prosper in disturbed and non-disturbed habitats. These invaders modify the dynamics and structure of populations and the composition of communities, which in turn can result in radical changes in wildlife habitat.

Silvicultural options for neotropical migratory birds

Publications Posted on: May 17, 2006
We review: factors that affect forest bird populations; basic concepts of silvicultural systems; potential impacts of these systems on neotropical migratory birds (NTMBs); and conclude with management recommendations for integrating NTMB conservation with forest management. We approach this topic from a regional-landscape scale to a forest stand-habitat scale, rather than the traditional stand-level approach.

Adding a landscape ecology perspective to conservation and management planning

Publications Posted on: May 17, 2006
We briefly review concepts in landscape ecology and discuss their relevance to the conservation and management of neotropical migrant landbirds. We then integrate a landscape perspective into a spatially-hierarchical framework for conservation and management planning for neotropical migrant landbirds (and other biota).

Integrated natural resource monitoring on Army lands and its application to conservation of neotropical birds

Publications Posted on: May 17, 2006
The U.S. Army is responsible for managing 5.0 million ha (12.4 million acres) of land on 186 major installations world-wide. The Land Condition Trend Analysis (LCTA) Program is the Army's integrated monitoring and data collection program designed to fulfill the Army's natural resource information and management needs.

Evaluation of mist-netting, nest-searching and other methods for monitoring demographic processes in landbird populations

Publications Posted on: May 17, 2006
Demographic processes (reproductive success, survival of young and adults, recruitment of young into the breeding population) are critical to monitoring and managing landbird populations. We discuss different techniques that have been used to monitor these demographic processes in landbird populations, focusing on constant-effort mist-netting (CEM).

The Monitoring Avian Productivity and Survivorship (MAPS) Program: overview and progress

Publications Posted on: May 17, 2006
It is generally agreed that populations of many North American landbird species, especially forest-inhabiting Neotropical migratory species in eastern North America, are declining.