really available to an animal, and assessing whether and what selection is eventually made by an individual. Adequately addressing the assumptions that
form the basis of habitat selection hypotheses proves to be a formidable
research design task. Equally challenging are problems with assessing habitat
quality, including the basic concept of optimal habitat and the sometimes false
paradigm that the best habitat always supports higher animal densities.
In chapter 5 John A. Litvaitis summarizes the current approaches and
describes the most recent innovations to investigating food habits and diets.
The limitations of each technique are discussed but the emphasis is on the
interpretation of the results provided by these techniques. A number of fundamental assumptions are neglected far too often when extrapolating individual
results to whole populations, and inadequate consideration of the spatiotemporal variance of populations is common. Litvaitis also suggests framing habitat and food use studies within an integrated approach and shows the potential of foraging theory as an aid in understanding variation in food habits.
Detection of time series of density and survival is the focus of chapter 6, by
Joseph S. Elkinton. Understanding the mechanism by which population
dynamics develop is of paramount importance for conservation and management, and this chapter discusses the use of density and mortality data to
deduce population changes and their causes. Density dependence is an especially important parameter that is difficult to isolate from correlated factors,
and Elkinton explores the statistical limitations of research design in detecting
different types of density dependence.
Population monitoring is a key topic in animal ecology and in most
wildlife conservation activities. However, James P. Gibbs, in chapter 7, shows
that the validity of the chosen population index is rarely assessed properly and
the design of a monitoring program usually is not adequate to permit a reasonable chance of detecting a trend or change. Gibbs discusses the many weaknesses and limitations of population indexes and shows how imprecise population indices often combine with inadequate study design (often imposed by
logistical constraints) to severely constrain the statistical power of populationmonitoring programs. After a thorough examination of the most common pitfalls of population monitoring, Gibbs points out the possible solutions. The
goals set out clearly before the initiation of any monitoring program should, at
a minimum, address the magnitude of change in the population index that
must be detected, what probability of false detections is to be tolerated, and
what frequency of failed detections is acceptable.
In chapter 8, Mark S. Boyce presents various types of predator–prey models used in ecological research and discusses the criteria by which a model is
P R E FA C E
xxix
form the basis of habitat selection hypotheses proves to be a formidable
research design task. Equally challenging are problems with assessing habitat
quality, including the basic concept of optimal habitat and the sometimes false
paradigm that the best habitat always supports higher animal densities.
In chapter 5 John A. Litvaitis summarizes the current approaches and
describes the most recent innovations to investigating food habits and diets.
The limitations of each technique are discussed but the emphasis is on the
interpretation of the results provided by these techniques. A number of fundamental assumptions are neglected far too often when extrapolating individual
results to whole populations, and inadequate consideration of the spatiotemporal variance of populations is common. Litvaitis also suggests framing habitat and food use studies within an integrated approach and shows the potential of foraging theory as an aid in understanding variation in food habits.
Detection of time series of density and survival is the focus of chapter 6, by
Joseph S. Elkinton. Understanding the mechanism by which population
dynamics develop is of paramount importance for conservation and management, and this chapter discusses the use of density and mortality data to
deduce population changes and their causes. Density dependence is an especially important parameter that is difficult to isolate from correlated factors,
and Elkinton explores the statistical limitations of research design in detecting
different types of density dependence.
Population monitoring is a key topic in animal ecology and in most
wildlife conservation activities. However, James P. Gibbs, in chapter 7, shows
that the validity of the chosen population index is rarely assessed properly and
the design of a monitoring program usually is not adequate to permit a reasonable chance of detecting a trend or change. Gibbs discusses the many weaknesses and limitations of population indexes and shows how imprecise population indices often combine with inadequate study design (often imposed by
logistical constraints) to severely constrain the statistical power of populationmonitoring programs. After a thorough examination of the most common pitfalls of population monitoring, Gibbs points out the possible solutions. The
goals set out clearly before the initiation of any monitoring program should, at
a minimum, address the magnitude of change in the population index that
must be detected, what probability of false detections is to be tolerated, and
what frequency of failed detections is acceptable.
In chapter 8, Mark S. Boyce presents various types of predator–prey models used in ecological research and discusses the criteria by which a model is
P R E FA C E
xxix