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Models for estimating abundance from repeated counts of an open metapopulation
1Department of Statistics, Oregon State University, Corvallis, Oregon 97331, USA. daild@science.oregonstate.edu
Biometrics
|July 29, 2010
Summary
This study introduces a generalized N-mixture model to test population closure assumptions and estimate animal abundance in open populations. The new model provides less biased abundance estimates than the original N-mixture model.
Area of Science:
- Ecology
- Wildlife Population Modeling
- Statistical Ecology
Background:
- N-mixture models estimate animal abundance with unknown detection probability.
- A key assumption is population closure (no migration, births, deaths).
- Closure has historically been verified only through biological arguments.
Purpose of the Study:
- To develop a generalized N-mixture model for formally testing population closure.
- To provide abundance estimates for open metapopulations.
- To estimate population dynamics parameters in open populations.
Main Methods:
- Generalization of the N-mixture model.
- Statistical testing of the closure assumption.
- Application to avian point count data (Mallards, American Robins).
Main Results:
- The generalized model allows formal statistical verification of closure.
- Estimates from the generalized model are less biased in open populations.
- The model successfully estimated population dynamics and abundance for American Robins.
Conclusions:
- The proposed generalized N-mixture model enhances ecological studies by allowing closure assumption testing.
- It provides robust abundance and population dynamics estimates for open metapopulations.
- This advances statistical methods in wildlife population monitoring.
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