The effects of human development, environmental factors, and a major highway on mammalian community composition in the Wasatch Mountains of northern Utah, USA

Abstract

Human development and roads threaten wildlife through distinct mechanisms and understanding the influence of these elements can better inform mitigation and conservation strategies. We used camera traps to quantify the effects of major roads, environmental factors, and human development on the mammalian community composition between sites north and south of a major interstate highway in northern Utah, USA. We found no significant differences in species richness nor community similarity across the north-south divide of the highway. Through Bayesian hierarchical modeling, we compared the effects of the distance to the highway, housing and human population density, normalized difference vegetation index (NDVI), and the human footprint index to changes in mammalian community composition and species-specific habitat usage. Community occupancy response, similarity, and species richness were negatively affected by increased housing and human population densities and positively affected by increased NDVI and decreased human footprint, whereas their response to the highway was more inconclusive. We conclude that mammalian community composition in our study area is influenced by both environmental conditions and human development while the effect of the highway was more nuanced, possibly due to the presence of a newly constructed wildlife overpass. Taken together, the lack of differences in species richness or community composition across the highway suggests that it may not currently exacerbate the effects of other anthropogenic sources of habitat fragmentation and highlights the need for additional research into humanwildlife conflict mitigation strategies. Kelsey A. Barnick and Austin M. Green contributed equally to this work and would like to be considered as co-first authors.

Effect of species‐level trait variation on urban exploitation in mammals

“…However, as our response variable (urbanization response) was itself estimated from a previous model, we had to account for this error in our second stage model. We therefore propagated the error from our species‐specific parameter estimates through each bGLM by modeling urbanization response as a random variable with associated “observation” error, where Urb i denotes the occupancy response of species i to urbanization, 𝛍 i is the mean estimated occupancy response of species i to urbanization, and 𝛔 i is the posterior SD of species i 's occupancy response to urbanization (Barnick et al, 2022; Kéry & Royle, 2015; Suraci et al, 2021). We then modeled urbanization response as a function of species average traits and trait variation using a Gaussian linear model, incorporating order‐specific intercepts and slopes, where species i belongs to order k and 𝛄 ₖ is an order‐specific intercept term, 𝛃 ₖ is an order‐specific slope term, trait i is the species‐specific trait value from the list of average trait and trait variation values (Table 1), and ε i is a species‐specific error term.…”

Solar Bird Banding: Notes on Changes in Avian Behavior While Mist-netting During an Eclipse

“…This research was conducted at the Red Butte Canyon Research Natural Area (RBC), a protected canyon located in the Wasatch Range of Utah, to the east of Salt Lake City and the University of Utah (Ehleringer et al 1992; Barnick et al 2022). This access-restricted site is only open to permitted researchers and has been protected since 1862 (Ehleringer et al 1992; Barnick et al 2022).…”

“…This research was conducted at the Red Butte Canyon Research Natural Area (RBC), a protected canyon located in the Wasatch Range of Utah, to the east of Salt Lake City and the University of Utah (Ehleringer et al 1992; Barnick et al 2022). This access-restricted site is only open to permitted researchers and has been protected since 1862 (Ehleringer et al 1992; Barnick et al 2022). Our bird banding station is located at Parleys Fork within the RBC around a central wetland at roughly 1736 m asl (40.787573, -111.796584), consisting of a wet meadow/marsh and several streams (including Red Butte Creek) surrounded by open montane forest and other riparian vegetation.…”