Introduction
Movement behavior is informative in capturing how animals respond to the
heterogeneity in their environment. These responses include broad-scale
decisions in the size and location of the home range (Burt 1943) as well
as finer scale responses to heterogeneity in the environment through
habitat selection decisions (Johnson 1980). Animals often vary in their
movement behavior, which can be due in part to individual personality
(Réale et al. 2010, Kaiser and Müller 2021), or plasticity in
individual- or population-level behavior (Stamps and Groothuis 2010,
Snell-Rood 2013). This variation can lead to directional reactions of
animals to their environment, known as functional responses, which can
include reactions to habitat (Mysterud and Ims 1998, Newediuk et al.
2022), prey (Holling 1965), forage (Spalinger and Hobbs 1992), or other
stimuli. Functional responses of animal spatial behavior to
anthropogenic factors have been documented in various species, including
in wolf (Canis lupus ) (Hebblewhite and Merrill 2008), caribou
(Rangifer tarandus caribou ) (Moreau et al. 2012), and moose
(Alces alces ) (Beyer et al. 2013) habitat selection and proximity
to humans. Habitat selection is a particularly informative behavior to
study because of the direct link between the spatial choices an
individual makes and variability in the environment (Johnson et al.
2002), and because it can have direct implications for an animal’s
fitness (Nilsen et al. 2004, Mayor et al. 2009). Habitat selection and
functional responses are especially important in the context of
anthropogenic change, when landscape compositions are constantly
undergoing modifications.
Animals can display a wide range of responses toward anthropogenic
factors. These responses can range from generic, or broad-scale
(hereafter referred to as generic responses), such as consistently
avoiding human activity or structures in their home range (Muhly et al.
2011, Leblond et al. 2013), and which could lead to increased home range
size for individuals inhabiting areas with greater levels of human
modification (O’Donnell and delBarco-Trillo 2020). At the other end of
this gradient, species can display nuanced, or refined, responses
(hereafter termed nuanced responses) to humans, such as only avoiding
anthropogenic features at a fine scale and during a certain periods of
the day (Tigas et al. 2002), seasonally (Johnson et al. 2005), or by
using a combination of spatiotemporal responses (Knopff et al. 2014).
Investigating individual and temporal variation in spatial behavior can
elucidate broader patterns in behavior, linking spatial ecology and
animal behavior (Hertel et al. 2020), as well as help draw conclusions
about population-level relationships with habitat (Bastille-Rousseau and
Wittemyer 2019). Here, we propose that a multi-faceted characterization
of a population that includes individual, spatial, and temporal
variation in space use form the basis of characterizing where a
population or species fall along a “generic-to-nuanced” gradient in
spatial responses. This gradient is especially informative in
characterizing animal responses to anthropogenic activities, which can
also be particularly useful for wide-ranging species which use a variety
of habitats with varying levels of human development.
Bobcats (Lynx rufus ) and coyotes (Canis latrans ) are two
mesocarnivores that fill the role of top predator in the absence of
large predators throughout much of North America (Laliberte and Ripple
2004, Roemer et al. 2009, Lesmeister et al. 2015). Bobcats are strictly
carnivorous and are believed to prefer forested habitat above other
habitat types (Litvaitis and Harrison 1989, Lesmeister et al. 2015).
Coyotes are more generalist in both diet and habitat and are found in
all habitats along a forested-to-rural gradient (Randa and Yunger 2006,
Lesmeister et al. 2015), and are more likely than bobcats to exploit
agricultural landscapes (Litvaitis and Harrison 1989, Nielsen et al.
2017). Both bobcats and coyotes have been observed to expand their home
range with increased fragmentation, but coyotes are more plastic and
adaptable to anthropogenic change, exploiting small resource patches on
a landscape scale, regardless of connection (Riley et al. 2003, Atwood
et al. 2004). Although mesocarnivores are a group expected to adapt
better than other species to human development (Červinka et al. 2014,
Streicher et al. 2021), they experience a spectrum of adaptability to
coexistence with humans based on flexibility in diet and suitable
habitat, as well as plasticity in behaviors like boldness and neophilia,
leading to a variety of responses to anthropogenic land modification
(Réale et al. 2007, Mason et al. 2013).
Here we studied how variation in anthropogenic activity shapes movement
behaviors of these mesocarnivore species and characterized where they
belong on the “generic-to-nuanced” gradient. Specifically, we
investigated how a gradient of human modification impacted home range
size and habitat selection of both species. We also evaluated how
habitat selection behaviors vary temporally and how individual variation
in this behavior could be linked to variation to the intensity of human
modification for an individual (functional response). Overall, given the
behavior of both mesocarnivores, we expected bobcat responses to be on
the generic end of the gradient, marked by stronger and more consistent
avoidance of human activities and overall larger home range when exposed
to human activities. Meanwhile, we expected coyote responses to be more
nuanced, with home-ranging behaviors less affected by human
modification, but with space-use showing more individual variation,
temporally-acute selection behaviors, and complexity in their functional
responses to human modification.