The adaptive value of habitat preferences from a multi-scale spatial perspective: insights from marsh-nesting avian species

Abstract

BackgroundHabitat selection and its adaptive outcomes are crucial features for animal life-history strategies. Nevertheless, congruence between habitat preferences and breeding success has been rarely demonstrated, which may result from the single-scale evaluation of animal choices. As habitat selection is a complex multi-scale process in many groups of animal species, investigating adaptiveness of habitat selection in a multi-scale framework is crucial. In this study, we explore whether habitat preferences acting at different spatial scales enhance the fitness of bird species, and check the appropriateness of single vs. multi-scale models. We expected that variables found to be more important for habitat selection at individual scale(s), would coherently play a major role in affecting nest survival at the same scale(s).MethodsWe considered habitat preferences of two Rallidae species, little crake (Zapornia parva) and water rail (Rallus aquaticus), at three spatial scales (landscape, territory, and nest-site) and related them to nest survival. Single-scale versus multi-scale models (GLS and glmmPQL) were compared to check which model better described adaptiveness of habitat preferences. Consistency between the effect of variables on habitat selection and on nest survival was checked to investigate their adaptive value.ResultsIn both species, multi-scale models for nest survival were more supported than single-scale ones. In little crake, the multi-scale model indicated vegetation density and water depth at the territory scale, as well as vegetation height at nest-site scale, as the most important variables. The first two variables were among the most important for nest survival and habitat selection, and the coherent effects suggested the adaptive value of habitat preferences. In water rail, the multi-scale model of nest survival showed vegetation density at territory scale and extent of emergent vegetation within landscape scale as the most important ones, although we found a consistent effect with the habitat selection model (and hence evidence for adaptiveness) only for the former.DiscussionOur work suggests caution when interpreting adaptiveness of habitat preferences at a single spatial scale because such an approach may under- or over-estimate the importance of habitat factors. As an example, we found evidence only for a weak effect of water depth at territory scale on little crake nest survival; however, according to the multi-scale analysis, such effect turned out to be important and appeared highly adaptive. Therefore, multi-scale approaches to the study of adaptive explanations for habitat selection mechanisms should be promoted.

Do spatial scale and life history affect fish–habitat relationships?

“…habitat variables was different at the 600-m and 1,200-m spatial scales in comparison with smaller scales, indicating that different variables are most important at these largest scales. For example, the nest survival of birds from the Family Rallidae is dependent upon different environmental variables at the scale of territories (e.g., water depth and vegetation density) and the scale of nests (e.g., vegetation height)(Jedlikowski & Brambilla, 2017). This is consistent with previous work in the region showing that macroalgae can be important habitat for fish (e.g., brown macroalgae Ecklonia radiata:Fobert & Swearer, 2017).…”

“…Similar variability in the importance of environmental predictors across spatial scales has been illustrated for other taxa. For example, the nest survival of birds from the Family Rallidae is dependent upon different environmental variables at the scale of territories (e.g., water depth and vegetation density) and the scale of nests (e.g., vegetation height) (Jedlikowski & Brambilla, 2017).…”

Nonideal nest box selection by tree swallows breeding in farmlands: Evidence for an ecological trap?

“…Because our landscape variables were too strongly correlated to fit a multiscale model (e.g., Jedlikowski & Brambilla, 2017 ), we had to choose one scale for each variable. In order to use the spatial scales most representative of tree swallows’ habitat selection, we performed a preference analysis (see Statistical Analysis section) for each land cover type.…”

“…We characterized landscape habitat composition by measuring the relative cover of forest, of perennial forage crops, and of water bodies and wetlands, within radii of 50, 100, 200, 300, 400, 500, 1000, 5000, 10,000, and Because our landscape variables were too strongly correlated to fit a multiscale model (e.g., Jedlikowski & Brambilla, 2017), we had to choose one scale for each variable. In order to use the spatial scales most representative of tree swallows' habitat selection, we performed a preference analysis (see Statistical Analysis section)…”

Fine‐Scale Habitat Selection by Breeding White‐Tailed Ptarmigan in Colorado

“…Across a larger area (patch scale), cover of forage forbs, rock and gravel, and shrubs are all important predictors of nesting habitat. Differential spatial scales are important to consider when evaluating habitat selection (Johnson 1980, Kristan 2006 to properly capture bird behaviors and choices (Wiens 1989), and to avoid improperly estimating the importance of habitat features on selection (Jedlikowski and Brambilla 2017).…”