8055 ‎(2)‎

• UCREFRP Catalog Number: 8055
• Author: Crowl, T. A. and N. W. Bouwes.
• Title: A Population Model for Four Endangered Colorado River Fishes - Final Report.
• USFW Year: 1998.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

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INTRODUCTION
Mathematical models can be useful tools for the conservation of threatened or
endangered species (Wootton and Bell 1992). Models fulfill 4 important functions for
these kinds of activities: 1) clarifying the critical data required to monitor the health of a
population; 2) determining the current status of data collection and analysis, and of the
population dynamics themselves; 3) aid in projecting the outcome of current
management strategies; and 4) providing insight into the most effective management
strategies given alternatives (Mertz 1971, Crouse et al. 1987, Lande 1988, Doak 1989,
Getz and Haight 1989, Menges 1990, Wootton and Bell 1992).
Historically, population models took relatively simplistic forms such as Lefkovitch or
Leslie Matrix models (sensu Ryel and Valdez 1994) in which transition probabilities
from one life stage to the next were used to determine how populations were
responding through time and how changes in the transition values might effect those
dynamics. It is now increasingly apparent that the spatial structure of populations
often has important effects on population dynamics (Holt 1985; Kareiva 1986, 1987;
Pulliam 1988). Incorporating population substructure into models and population
monitoring schemes may be critical to predict future population dynamics accurately
which may allow either different management strategies altogether (Lande 1988,
Pulliam 1988, Doak 1989) or at least a quantitative method for prioritizing where efforts
are to take place for population enhancement.
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