Abundance-based approaches

Abstract

Across a wide range of different organisms, abundance data form one of the backbones for understanding the dynamics of populations. This type of data consists of measures of population size over time or space in the form of numbers of individuals, biomass, areal cover, or other measures. Abundance data contain no direct information about demographic processes but are available at larger scales or higher resolution in space and time than direct demographic data. This chapter introduces some of the basic statistical modeling strategies that can be used to learn about populations from abundance data in the absence of information about demographic details. These strategies include standard but flexible regression techniques, including mixed and additive models, time-series methods such as auto-regressive and state-space models, as well as simple population growth models derived from ecological theory.