Patuxent Wildlife Research Center

Decision Science and Populations

USGS Patuxent is world-renowned for the development of robust statistical techniques used in the assessment of wildlife population dynamics and the application of structured decision making to problems in natural resource management and conservation.

Filter Total Items: 7
Date published: March 26, 2018
Status: Active

Structured Decision Making

The biggest natural resource management challenges include competing views of the value and uses of those resources in society. Patuxent scientists develop methods to manage resources given those competing views under a “structured decision making” (SDM) framework. Our scientists both practice and train others in key SDM skills, such as model development and monitoring design.

Date published: March 23, 2018
Status: Active

Hierarchical Modeling

Hierarchical models, also known as mutl-level and mixed effects models, have advanced the field of population ecology with inferences about population dynamics at broad spatial and temporal scales. The analysis of hierarchical models has been facilitated by recent advances in Bayesian analysis, and computationally intensive techniques such as Markov Chain Monte Carlo (see Mathematical modeling...

Date published: March 22, 2018
Status: Active


Many wildlife studies seek to understand changes or differences in the proportion of sites occupied by a species of interest. These studies are hampered by imperfect detection of these species, which can result in some sites appearing to be unoccupied that are actually occupied. Occupancy models solve this problem and produce unbiased estimates of occupancy (ie, occurrence) and related...

Date published: March 21, 2018
Status: Active

Adaptive Management

Adaptive management (AM) combines management and monitoring, with the aim of updating knowledge and improving decision-making over time. We provide a guide for managers who may realize the potential of AM, but are unsure where to start. The urgent need for iterative management decisions, the existence of uncertainty, and the opportunity for learning offered by often highly-controlled captive...

Date published: March 21, 2018
Status: Active

Capture-Mark-Recapture Science

Capture-Mark-Recapture (CMR) can be viewed as an animal survey method in which the count statistic is the total number of animals caught, and the associated detection probability is the probability of capture.  The method involves capturing a number of animals, marking them, releasing them back into the population, and then determining the ratio of marked to unmarked animals in the population...

Date published: March 20, 2018
Status: Active

Mathematical Modeling

A formal framework that revolves around the construction of a mathematical expression using equations, statements or formulas as representation of a system, behavior, or process to  simulate the behavior of the system, a series of relationships, or process under study.

Date published: March 19, 2018
Status: Active

Population Estimation

Determining the size of animal populations is fundamental to wildlife management and how such populations change over time and space can provide insights into ecosystem function and associated processes.   Patuxent scientists’ utilize a number of robust statistical techniques to generate these estimates and to improve our understanding of population dynamics.