Changes in home range sizes and population densities of carnivore species along the natural to urban habitat gradient

Abstract

1.With rapid development and the spread of urbanized land, there is an increasing need to understand species' responses to urban conditions. Carnivores are considered to be sensitive to urbanization; however, there is ample evidence that some carnivore species successfully inhabit urban areas, and human-modified habitats have recently been recognized as an important refuge for several species. 2. Despite the increasing number of studies on urban carnivore ecology, no comprehensive cross-species comparisons have been made in order to assess the effects of urbanization on the spatial ecology of carnivores and their population densities. Such a review could provide interesting insight into how some carnivore species respond to increasing urbanization. Specifically, we examine changes in population density and home range size of eight carnivore species that occur along the natural-urban environmental gradient. 3. Using data from 411 articles, we provide evidence that the home range size of carnivores decreases in six out of eight species, and population density increases in three out of six species along the natural-urban habitat gradient. The densitydependent pattern of variation in home range size is consistent in all species studied. 4. Our results emphasize the remarkable ability of some carnivore species to adapt to novel environments through their behavioural flexibility and life history adaptations. We outline ideas for future research that could be adopted in addressing this phenomenon, namely comparative approaches and detailed studies of biotic and abiotic conditions along natural-urban gradients.Carnivores along the natural-urban habitat gradient M. Šálek, L. Drahníková and E. Tkadlec

Mesopredator spatial and temporal responses to large predators and human development in the Santa Cruz Mountains of California

“…Our study results add to the global body of evidence that documents both the ability of carnivores to coexist in close proximity with humans and the diverse repercussions that such intimate cohabitation has on the carnivore community (Goad et al, 2014;Recio et al in press;Schuette et al, 2013;Šálek et al, 2014). Unlike previous studies, we simultaneously investigated how the predator community was affected by the combined influences of increasing human development and activity and declining apex predator occupancy and activity.…”

“…Habitat fragmentation due to human development can lead to the extirpation of top predators (Gehrt et al, 2010;Šálek et al, 2014) and irreversibly alter ecosystem stability (Hansen et al, 2005). Exurban development (0.06-2.5 houses/hectare) is the fastest growing form of land use change in the United States, and building low-density developments adjacent to wildlands results in habitat fragmentation, increased human wildlife contact and conflict, and homogenization of ecological communities (Hansen et al, 2005;McKinney, 2006).…”

Habitat urbanization and its effects on birds

“…Despite their former negligence as important predators in cities, the response of raptor species to urbanization can also quickly change: a number of carnivorous bird species that were formerly absent as breeders in urban areas have been documented to establish breeding populations within cities recently (Chace & Walsh 2006) such as the Eurasian Sparrowhawk Accipiter nisus, the Northern Goshawk Accipiter gentilis (Rutz 2008), the Eurasian Kestrel Falco tinnunculus (Salvati et al 1999, KÜbler et al 2005, Morandini 2006, Sumasgutner et al 2014 or the Merlin Falco columbarius (Sodhi & Oliphant 1992), supposedly responding to abundant prey populations and/or availability of nest sites in cities, or a delayed response to the decreased prosecution by humans. For example the Eurasian Sparrowhawk is known to be one of the principal predators of smaller bodied songbird species, and its numbers are increasing in several urbanized habitats (Chamberlain et al 2009b), reaching high densities in large European cities like Hamburg (Risch et al 1996) or Prague (Kelcey & Rheinwald 2005).…”

Emotionalization in Science Communication: The Impact of Narratives and Visual Representations on Knowledge Gain and Risk Perception

“…The incidence of human-fox interactions has increased with human land development, the process of urbanization, and the expansion of human population and farming frontiers. The active colonization of urban habitats by foxes increases the potential for conflict (Bateman and Fleming, 2012;Šálek et al, 2015). In this situation, science communication is a crucial element in wildlife management and policy.…”