Determining habitat quality for species that demonstrate dynamic habitat selection

Abstract

Determining habitat quality for wildlife populations requires relating a species' habitat to its survival and reproduction. Within a season, species occurrence and density can be disconnected from measures of habitat quality when resources are highly seasonal, unpredictable over time, and patchy. Here we establish an explicit link among dynamic selection of changing resources, spatio‐temporal species distributions, and fitness for predictive abundance and occurrence models that are used for short‐term water management and long‐term restoration planning. We used the wading bird distribution and evaluation models (WADEM) that estimate (1) daily changes in selection across resource gradients, (2) landscape abundance of flocks and individuals, (3) conspecific foraging aggregation, and (4) resource unit occurrence (at fixed 400 m cells) to quantify habitat quality and its consequences on reproduction for wetland indicator species. We linked maximum annual numbers of nests detected across the study area and nesting success of Great Egrets (Ardea alba), White Ibises (Eudocimus albus), and Wood Storks (Mycteria americana) over a 20‐year period to estimated daily dynamics of food resources produced by WADEM over a 7490 km2 area. For all species, increases in predicted species abundance in March and high abundance in April were strongly linked to breeding responses. Great Egret nesting effort and success were higher when birds also showed greater conspecific foraging aggregation. Synthesis and applications: This study provides the first empirical evidence that dynamic habitat selection processes and distributions of wading birds over environmental gradients are linked with reproductive measures over periods of decades. Further, predictor variables at a variety of temporal (daily‐multiannual) resolutions and spatial (400 m to regional) scales effectively explained variation in ecological processes that change habitat quality. The process used here allows managers to develop short‐ and long‐term conservation strategies that (1) consider flexible behavioral patterns and (2) are robust to environmental variation over time.

Extreme climatic events constrain space use and survival of a ground‐nesting bird

“…However, how researchers define spatial and temporal scales is important and can influence our understanding of how extreme events can directly affect organisms (Mooij et al, 2002). At fine temporal and spatial scales, resource use is highly dynamic and can vary based on the availability of other necessary resources (Mooij et al, 2002;Beerens et al, 2015), environmental conditions (Mooij et al, 2002;Hovick et al, 2014;Carroll et al, 2015a), or with biotic interactions (Ryder & Sillet, 2016). These patterns may exist at smaller scales of resolution than typically studied (Dunbar et al, 2009;Maron et al, 2015), and as a result, extreme events may facilitate changes in space use and/or survival at both fine temporal (Carroll et al, 2015a) and spatial (Hovick et al, 2014) scales.…”

Predicting wading bird and aquatic faunal responses to ecosystem restoration scenarios

“…Wader distribution and evaluation modeling (WADEM) was developed to predict how wading birds respond to the changes in hydrology that will occur with Everglades ecosystem restoration (Beerens et al 2015 a , 2015 b ). It can predict Great Egret ( Ardea alba ), White Ibis ( Eudocimus albus ), and Wood Stork ( Mycteria americana ) foraging distributions across changing habitat conditions based on their selection of prey resources (defined by daily–multiannual hydrologic variables).…”

Behavioral modifications lead to disparate demographic consequences in two sympatric species

“…Research has often shown that space use can be misleading indicators of habitat quality (i.e., ecological traps; Bacon et al, 2016;Donovan & Thompson, 2001;Gates & Gysel, 1978;van Horne, 1983) because individuals may not always be able to determine habitat quality and instead rely on environmental cues to guide space use (Kristan, 2003;Storch & Frynta, 1999). Thus, determining a link between space use and demographic parameters helps ensure the predictive capabilities of using such patterns for conservation purposes (Beerens, Frederick, Noonburg, & Gawlik, 2015;Folmer & Piersma, 2012). Thus, determining a link between space use and demographic parameters helps ensure the predictive capabilities of using such patterns for conservation purposes (Beerens, Frederick, Noonburg, & Gawlik, 2015;Folmer & Piersma, 2012).…”

“…Furthermore, this relationship can be highly variable across species and vegetation communities (Bock & Jones, 2004). Thus, determining a link between space use and demographic parameters helps ensure the predictive capabilities of using such patterns for conservation purposes (Beerens, Frederick, Noonburg, & Gawlik, 2015;Folmer & Piersma, 2012).…”