To predict the niche, model colonization and extinction

Abstract

Ecologists frequently try to predict the future geographic distributions of species. Most studies assume that the current distribution of a species reflects its environmental requirements (i.e., the species' niche). However, the current distributions of many species are unlikely to be at equilibrium with the current distribution of environmental conditions, both because of ongoing invasions and because the distribution of suitable environmental conditions is always changing. This mismatch between the equilibrium assumptions inherent in many analyses and the disequilibrium conditions in the real world leads to inaccurate predictions of species' geographic distributions and suggests the need for theory and analytical tools that avoid equilibrium assumptions. Here, we develop a general theory of environmental associations during periods of transient dynamics. We show that time-invariant relationships between environmental conditions and rates of local colonization and extinction can produce substantial temporal variation in occupancy-environment relationships. We then estimate occupancy-environment relationships during three avian invasions. Changes in occupancy-environment relationships over time differ among species but are predicted by dynamic occupancy models. Since estimates of the occupancy-environment relationships themselves are frequently poor predictors of future occupancy patterns, research should increasingly focus on characterizing how rates of local colonization and extinction vary with environmental conditions.

Distribution of priority grassland bird habitats in the Prairie Pothole Region of Canada

“…In light of recent global changes in climate and habitats, species-environment relationships may become more transient (Yackulic et al 2015). Our models represent a baseline for the development of more sophisticated dynamic occupancy models that could include time varying conditions for both habitat and climate.…”

Species interactions and the effects of climate variability on a wetland amphibian metacommunity

“…Dynamic models can be powerful tools for disentangling the processes that lead to changes in species distributions (Franklin 2010, Yackulic et al 2015. Characterizing the underlying colonization and extinction processes that determine metacommunity dynamics can provide key insights into how changes in environmental and climatic variability are likely to impact amphibian occurrence on the landscape , Semlitsch et al 2015.…”

“…Occurrence, or the presence of a species at a particular location, depends on (1) species interactions (i.e., predator-prey or inter-and intraspecific competition; Ives 1995, Gilman et al 2010, Zarnetske et al 2012) and (2) characteristics of the physical environment that define habitat suitability for each species (Pounds and Crump 1994, Kupferberg 1996, Brooks 2004, Todd et al 2009). Patterns in species occurrence are scale dependent and can be used to inform species' distributions and serve as indicators of local habitat quality (Leibold et al 2004, Yackulic et al 2015. Patterns in species occurrence are scale dependent and can be used to inform species' distributions and serve as indicators of local habitat quality (Leibold et al 2004, Yackulic et al 2015.…”

Occupancy dynamics in human‐modified landscapes in a tropical island: implications for conservation design

“…exploit novel resources) or habitat features to bridge gaps of inhospitable matrices or survive in remnant patches (Saunders et al, 1991;Croci et al, 2008). The manner in which landscape changes influence faunal behaviour and demographic processes have a determinant influence on distribution, and ultimately, persistence (Hanski, 1998;Brotons et al, 2003;Watling et al, 2011;Yackulic et al, 2015).…”

“…The theoretical foundation for these incidence functions and potential application to conservation design have been advanced in the literature (e.g. Diamond, 1975;Gilpin & Diamond, 1981;Hanski, 1994Hanski, & 1998Yackulic et al, 2015). This body of work underscores that changes in occurrence are mediated by the degree of isolation, size and quality of patches or points of interest on the landscape.…”