ALEX: A model for the viability analysis of spatially structured populations

doi:10.1016/0006-3207(95)90039-X

Biological Conservation

Volume 73, Issue 2, 1995, Pages 143-150

https://doi.org/10.1016/0006-3207(95)90039-X Get rights and content

Abstract

A new generic model for assessing the viability of spatially structured populations, ALEX (Analysis of the Likelihood of EXtinction), is described. Strengths and weaknesses of ALEX are discussed. ALEX only models one sex, ignores genetics, and is inadequate for modelling the dynamics of very small populations. However ALEX contains four features that make it useful for assessing the merits of different management options for populations that are distributed in a spatially complex landscape: (1) ALEX allows each patch to have different qualities including a habitat variable that may respond to catastrophes. In this way the dynamics of species which prefer a particular successional stage of a habitat can be modelled. (2) ALEX allows the user to specify a wide variety of catastrophic processes that affect and may depend on population size and/or the state of the habitat in a patch. (3) Sensitivity analysis is essential to the PVA process. ALEX allows automatic sensitivity analysis of most parameters. Although demographic stochasticity is modelled, ALEX can quickly simulate the dynamics of very large populations. (4) Modelling movement between patches by individuals is an important part of the dynamics of spatially structured populations. ALEX permits two types of movement by individuals. This allows the user to explore the importance of corridors, habitat selection, and mortality associated with dispersal.

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^∗: Present address: Department of Applied Mathematics, The University of Adelaide, Adelaide, SA 5005, Australia

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ALEX: A model for the viability analysis of spatially structured populations

Abstract

Biol. Conserv.

Biol. Conserv.

Biol. Conserv.

Biol. Conserv.

Biol. Conserv.

Biol. Conserv.

Biol. Conserv.

Math. Com. Simul.

Biol. Conserv.

Biol. Conserv.

Ecol. Modell.

Biol. Conserv.

A Population Viability Analysis for African elephant (Loxodonta africana): How big should reserves be?

Conserv. Biol.

Population viability analysis

Ann. Rev. Ecol. Syst.

Risk assessment in conservation biology

The effect of initial distribution on extinction risks: implications for the reintroduction of Leadbeater's possum

A stochastic model for the viability of Banksia cuneata populations: environmental, demographic and genetic effects

J. Appl. Ecol.

RAMAS/stage: generalised stage-based modelling for population dynamics

RAMAS/age: modelling fluctuations in age-structured populations

The dangers of being few: demographic risk analysis for rare species extinction

N. Y. St. Mus. Bull.

The demography of chance extinction

Quasiextinction probabilities as a measure of impact on population growth

Risk Anal.

Population viability analysis for a small population of red-cockaded woodpeckers and an evaluation of enhancement strategies

Conserv. Biol.