Human expansion precipitates niche expansion for an opportunistic apex predator (Puma concolor).

Wynne E Moss,Mathew W Alldredge,Kenneth A Logan,Jonathan N Pauli

doi:10.1038/srep39639

Wynne E Moss, Mathew W Alldredge + Show 2 more

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https://doi.org/10.1038/srep39639

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Abstract

There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation. Yet, little is known about processes regulating these novel ecosystems, or behaviours employed by species adapting to them. We evaluated the isotopic niche of an apex carnivore, the cougar (Puma concolor), over broad spatiotemporal scales and in a region characterized by rapid landscape change. We detected a shift in resource use, from near complete specialization on native herbivores in wildlands to greater use of exotic and invasive species by cougars in contemporary urban interfaces. We show that 25 years ago, cougars inhabiting these same urban interfaces possessed diets that were intermediate. Thus, niche expansion followed human expansion over both time and space, indicating that an important top predator is interacting with prey in novel ways. Thus, though human-dominated landscapes can provide sufficient resources for apex carnivores, they do not necessarily preserve their ecological relationships.

Highlights

There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation
We found that land use changes corresponded with shifts in dietary inputs and overall isotopic niche, and may indicate a changing ecology for cougars in these novel and developing landscapes
Though the land use change in the urban interface of Colorado’s Front Range over the past 25 years has primarily consisted of rural-to-exurban transformation (Supplementary Table S2), it appears this intensification of development is associated with large and rapid changes in diet composition for cougar inhabitants

Summary

Introduction

There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation. Though human-dominated landscapes can provide sufficient resources for apex carnivores, they do not necessarily preserve their ecological relationships. Accumulating evidence suggests that urban ecosystems can represent viable habitat for species of conservation importance[4]. Though much of our understanding of large carnivore ecology is derived from wildland systems, accumulating evidence suggests that habitat development significantly alters their behaviour and ecology in predictable ways. Due to shifts in prey communities, bottom-up subsidies, and altered risk landscapes in these emerging developed ecosystems, resource use of apex carnivores can differ strongly from historic patterns[11]. We provide evidence that an ecologically important and rebounding apex carnivore[15], the cougar (Puma concolor), has recently diversified its resource use and, is expanding its niche and www.nature.com/scientificreports/

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