Skip to main content
U.S. flag

An official website of the United States government

Hierarchical Modeling

Filter Total Items: 13

Red Knot Migration and Population Ecology

Eastern Ecological Science Center biologists are studying migration and population ecology of the rufa red knot, a bird species that is dependent on horseshoe crab eggs to complete its trans-hemispheric migration. The birds' spring migration is timed with spawning of horseshoe crabs because the eggs are the perfect food for a migrating red knot.
link

Red Knot Migration and Population Ecology

Eastern Ecological Science Center biologists are studying migration and population ecology of the rufa red knot, a bird species that is dependent on horseshoe crab eggs to complete its trans-hemispheric migration. The birds' spring migration is timed with spawning of horseshoe crabs because the eggs are the perfect food for a migrating red knot.
Learn More

Northeast Amphibian Research and Monitoring Initiative

The USGS Amphibian Research and Monitoring Initiative (ARMI) is designed to determine where populations of amphibians are present, to monitor specific apex populations, and to investigate potential causes of amphibian declines, diseases, and malformations. The Northeast Region of ARMI encompasses thirteen states (Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New...
link

Northeast Amphibian Research and Monitoring Initiative

The USGS Amphibian Research and Monitoring Initiative (ARMI) is designed to determine where populations of amphibians are present, to monitor specific apex populations, and to investigate potential causes of amphibian declines, diseases, and malformations. The Northeast Region of ARMI encompasses thirteen states (Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New...
Learn More

Evaluating the Design of the Waterfowl Breeding Population and Habitat Survey

The Waterfowl Breeding Population and Habitat Survey (WBPHS) is a primary source of waterfowl population status and trend information for management of ducks in North America. The survey has not been reviewed in several decades, and since the last review new analysis approaches and information needs have created a need to reassess the design, scope of inference, and analysis of the survey to...
link

Evaluating the Design of the Waterfowl Breeding Population and Habitat Survey

The Waterfowl Breeding Population and Habitat Survey (WBPHS) is a primary source of waterfowl population status and trend information for management of ducks in North America. The survey has not been reviewed in several decades, and since the last review new analysis approaches and information needs have created a need to reassess the design, scope of inference, and analysis of the survey to...
Learn More

Deriving Spatial Waterfowl Inputs for Disease Risk Modeling

This project is an effort to create spatially and temporally explicit models for waterfowl distribution across the United States for use in avian influenza transmission risk modeling.
link

Deriving Spatial Waterfowl Inputs for Disease Risk Modeling

This project is an effort to create spatially and temporally explicit models for waterfowl distribution across the United States for use in avian influenza transmission risk modeling.
Learn More

Assessing Amphibian Disease Risk in the Northeast

Disease in amphibian populations can have a range of effects, from devastating declines following introduction of a novel pathogen to recurring breakout events on a landscape. Elucidating mechanisms underlying the effects of diseases on amphibian populations is crucial to help managers make appropriate decisions to achieve management goals for amphibians.
link

Assessing Amphibian Disease Risk in the Northeast

Disease in amphibian populations can have a range of effects, from devastating declines following introduction of a novel pathogen to recurring breakout events on a landscape. Elucidating mechanisms underlying the effects of diseases on amphibian populations is crucial to help managers make appropriate decisions to achieve management goals for amphibians.
Learn More

Post-Hurricane Sandy Vegetation Recovery in the Presence of a Hyper-abundant Deer Population

The Challenge: The primary dune along barrier island beaches protects leeward vegetation from tidal fluctuation, salt spray and storm surge. However, storm surges like those experienced during Hurricane Sandy can obliterate the primary dune, transporting sand inland and burying existing vegetation. The dune rebuilds naturally as recovering vegetation traps wind-blown and waterborne sand. The rate...
link

Post-Hurricane Sandy Vegetation Recovery in the Presence of a Hyper-abundant Deer Population

The Challenge: The primary dune along barrier island beaches protects leeward vegetation from tidal fluctuation, salt spray and storm surge. However, storm surges like those experienced during Hurricane Sandy can obliterate the primary dune, transporting sand inland and burying existing vegetation. The dune rebuilds naturally as recovering vegetation traps wind-blown and waterborne sand. The rate...
Learn More

Estimation of Density and Abundance of Biological Populations on National Parks and Wildlife Refuges Through Distance Sampling

The Challenge: Assessing the status and trends of populations of biological organisms is an important management goal and a recurrent theme in USGS research. Often, the most basic question of “how many are there?” remains elusive, thus making management decisions more difficult. This study continues a long-term commitment of technical support for the use of distance sampling for wildlife...
link

Estimation of Density and Abundance of Biological Populations on National Parks and Wildlife Refuges Through Distance Sampling

The Challenge: Assessing the status and trends of populations of biological organisms is an important management goal and a recurrent theme in USGS research. Often, the most basic question of “how many are there?” remains elusive, thus making management decisions more difficult. This study continues a long-term commitment of technical support for the use of distance sampling for wildlife...
Learn More

Implementing Cross Validation Approaches for Model Selection and Evaluating Goodness of Fit in Complex Hierarchical Models

It is (relatively) easy to construct complex hierarchical models for analysis of the North American Breeding Bird Survey (BBS), but deciding which model best describes population change is difficult. We are developing methods for model selection for BBS and other important survey data sets, and using them to refine our estimates of population change from this important survey.
link

Implementing Cross Validation Approaches for Model Selection and Evaluating Goodness of Fit in Complex Hierarchical Models

It is (relatively) easy to construct complex hierarchical models for analysis of the North American Breeding Bird Survey (BBS), but deciding which model best describes population change is difficult. We are developing methods for model selection for BBS and other important survey data sets, and using them to refine our estimates of population change from this important survey.
Learn More

Design and Analysis of Surveys for Estimation of Temporal and Spatial Change in Animal Populations

Designing and analyzing large-scale animal surveys is an important focus of our research. Although we conduct research into analysis methods for many surveys, the primary focus of this project is to conduct analyses and develop web-based summaries of data from the North American Breeding Bird Survey (BBS).
link

Design and Analysis of Surveys for Estimation of Temporal and Spatial Change in Animal Populations

Designing and analyzing large-scale animal surveys is an important focus of our research. Although we conduct research into analysis methods for many surveys, the primary focus of this project is to conduct analyses and develop web-based summaries of data from the North American Breeding Bird Survey (BBS).
Learn More

Hierarchical Models of Animal Abundance and Occurrence

The Challenge: Research goals of this project are to develop models, statistical methods, sampling strategies and tools for inference about animal population status from survey data. Survey data are always subject to a number of observation processes that induce bias and error. In particular, inferences are based on spatial sampling – we can only ever sample a subset of locations where species...
link

Hierarchical Models of Animal Abundance and Occurrence

The Challenge: Research goals of this project are to develop models, statistical methods, sampling strategies and tools for inference about animal population status from survey data. Survey data are always subject to a number of observation processes that induce bias and error. In particular, inferences are based on spatial sampling – we can only ever sample a subset of locations where species...
Learn More

Spatial Capture-Recapture Models to Estimate Abundance and Density of Animal Populations

The Challenge: For decades, capture-recapture methods have been the cornerstone of ecological statistics as applied to population biology. While capture-recapture has become the standard sampling and analytical framework for the study of population processes (Williams, Nichols & Conroy 2002) it has advanced independent of and remained unconnected to the spatial structure of the population or the...
link

Spatial Capture-Recapture Models to Estimate Abundance and Density of Animal Populations

The Challenge: For decades, capture-recapture methods have been the cornerstone of ecological statistics as applied to population biology. While capture-recapture has become the standard sampling and analytical framework for the study of population processes (Williams, Nichols & Conroy 2002) it has advanced independent of and remained unconnected to the spatial structure of the population or the...
Learn More

Hierarchical Models for Estimation of Population Parameters

The Challenge: Much of wildlife research consists of the description of variation in data. Some of the variation results from spatial and temporal change in populations, while some results from biologically irrelevant sampling variation induced by the process of data collection. Distinguishing relevant from irrelevant variation is the first task of statistical analysis, but the job does not end...
link

Hierarchical Models for Estimation of Population Parameters

The Challenge: Much of wildlife research consists of the description of variation in data. Some of the variation results from spatial and temporal change in populations, while some results from biologically irrelevant sampling variation induced by the process of data collection. Distinguishing relevant from irrelevant variation is the first task of statistical analysis, but the job does not end...
Learn More