The relative importance of biotic and abiotic determinants of temporal occupancy for avian species in North America

Abstract

28Aim 29We examined the relative importance of competitor abundance and environmental variables in 30 determining the species distributions of 175 bird species across North America. Unlike previous 31 studies, which tend to model distributions in terms of presence and absence, we take advantage 32 of a geographically extensive dataset of community time series to model the temporal occupancy 33 of species at sites throughout their expected range. 34Location 35 North America. 36 37 2001-2015. 38 Major taxa studied 39 175 bird species. 40 Time period Methods 41We calculated variation in temporal occupancy across geographic range and used variance 42 partitioning and Bayesian hierarchical models to evaluate the relative importance of 1) the 43 abundance of potential competitors and 2) the environment (elevation, temperature, precipitation, 44 vegetation index) for determining temporal occupancy. We also created a null model to test 45 3 whether designated competitor species predicted variation in occupancy better than non-46 competitor species. 47 Results 48On average, the environment explained more variance in occupancy than competitor abundance, 49 but this varied by species. For certain species, competitor abundance explained more variance 50 than the environment. Species with larger range sizes, larger range overlap with competitors, and 51 that occurred at higher mean temperatures had a higher proportion of variance explained by the 52 environment than competitor abundance. The abundance of competitor species had a stronger 53 effect on focal species occupancy than non-competitor species in the null model. 54 Main conclusions 55Temporal occupancy represents a new way of describing species distributions that is 56 complementary to presence/absence or abundance. Geographic variation in temporal occupancy 57 was explained by both biotic and abiotic drivers, and abiotic drivers explained more variation in 58 temporal occupancy than abundance on average. Species traits also play a role in determining 59 whether variation in temporal occupancy is best explained by biotic or abiotic drivers. The 60 results of our study can improve species distribution models, particularly by accounting for 61 competitive interactions. 62 63 keywords: competition, environmental filtering, occupancy, spatial scale, species distribution, 64 species interactions 65 66 67 68

Metapopulation‐level associations in positively interacting stream fishes

“…Our study has two potential limitations which should be considered in the future study. First, negative interactions can also influence species distributions (Chesson 2000, Englund et al 2009, Taylor et al 2020. However, the effects of negative interactions are often masked by other environmental drivers at larger spatial scales (Hoeinghaus et al 2007, Ettinger andHilleRisLambers 2013) or can exert complex patterns due to non-linear effects of predator-prey interactions (Kadoya et al 2018).…”

“…Understanding factors affecting species distribution is a key topic in ecology due to its direct implications for biodiversity conservation. While there is a long history of relating species distributions to abiotic factors, a growing body of evidence suggests that biotic interactions can play comparable roles in driving species distribution patterns (Wisz et al 2013, Taylor et al 2020. For example, negative species interactions including…”

Rescue effect drives local persistence of fish species in the Upper Paraná River floodplain

“…how frequently a species is detected in a determined location). The study of temporal occupancy allows the identification of frequent and transient species (Magurran & Henderson, 2003; Supp et al., 2015), a temporal analogue of Hanski's core and satellite species (Hanski, 1982), complementing the traditional measures of spatial distribution (Taylor et al., 2019). Frequent species are those permanent members of the community, with high temporal persistence, while transient species are those that enter the community sporadically and may constitute most of the species in a local assemblage (Taylor et al., 2018).…”

“…Despite the rich literature on the mechanisms behind spatial occupancy, the drivers of interspecific variation in temporal occupancy or local persistence remain less investigated empirically (Gotelli & Taylor, 1999a; Hansen & Carey, 2015; Taylor et al., 2019). Furthermore, tests of predictors encompassing many hypotheses behind this variation are not usual (but see examples in Supp et al., 2015 and Taylor et al., 2019).…”

“…Despite the rich literature on the mechanisms behind spatial occupancy, the drivers of interspecific variation in temporal occupancy or local persistence remain less investigated empirically (Gotelli & Taylor, 1999a; Hansen & Carey, 2015; Taylor et al., 2019). Furthermore, tests of predictors encompassing many hypotheses behind this variation are not usual (but see examples in Supp et al., 2015 and Taylor et al., 2019). This occurs despite the importance of this approach for identifying relevant variables in ecological models (Houlahan et al., 2017) and testing for their generality in face of the heterogeneity and variability of ecological systems (Patil & Parmigiani, 2018), either inherent or human‐driven.…”