Ungulate Herd Sizes and the Risk of Predation by Wild Dogs

2019 ◽  
pp. 124-144
Keyword(s):  
2016 ◽  
Vol 12 (5) ◽  
pp. 20151053 ◽  
Author(s):  
Peter B. Banks ◽  
Andrew Daly ◽  
Jenna P. Bytheway

Many studies have reported the aversive reactions of prey towards a predator's odour signals (e.g. urine marks), a behaviour widely thought to reduce the risk of predation by the predator. However, because odour signals persist in the environment, they are vulnerable to exploitation and eavesdropping by predators, prey and conspecifics. As such, scent patches created by one species might attract other species interested in information about their enemies. We studied this phenomenon by examining red fox investigation of odours from conspecifics and competing species in order to understand what prey are responding to when avoiding the odours of a predator. Surprisingly, foxes showed limited interest in conspecific odours but were highly interested in the odours of their competitors (wild dogs and feral cats), suggesting that odours are likely to play an important role in mediating competitive interactions. Importantly, our results identify that simple, dyadic interpretations of prey responses to a predator odour (i.e. cat odour = risk of cat encounter = fear of cats) can no longer be assumed in ecological or psychology research. Instead, interactions mediated by olfactory cues are more complex than previously thought and are likely to form a complicated olfactory web of interactions.


Author(s):  
Xavier Lambin

The dependency of mustelid demographic rates on prey abundance has the potential to cause a strong coupling between predator-prey populations. Data on mustelid dynamics show that such strong reciprocal interactions only materialise in some restricted conditions. Bite-size mustelid predators searching for scarce, depleted prey expose themselves to increased risk of predation by larger predators of small mammal that are themselves searching for similar prey species. As voles or muskrats become scarcer, weasels and mink searching for prey over larger areas become increasingly exposed to intra-guild predation, unless they operate in a habitat refuge such as the sub-nivean space. Where larger predators are sufficiently abundant or exert year-round predation pressure on small mustelids, their impact on mustelids may impose biological barrier to dispersal that are sufficient to weaken the coupling between small mustelids and their rodent prey, and thus impose a degree of top down limitation on mustelids.


1994 ◽  
Vol 15 (4) ◽  
pp. 413-416 ◽  
Author(s):  
H. Saint Girons

AbstractIf one accepts that the number of times that vipers are observed in the field in any given season is an indirect measure of the overall risk of predation run by such diurnal predators hunting by vision, the results obtained in this study show that risk of predation is particularly high in males during the period of mating and in females when pregnant.


Oryx ◽  
2021 ◽  
pp. 1-9
Author(s):  
Helen M. K. O'Neill ◽  
Sarah M. Durant ◽  
Stefanie Strebel ◽  
Rosie Woodroffe

Abstract Wildlife fences are often considered an important tool in conservation. Fences are used in attempts to prevent human–wildlife conflict and reduce poaching, despite known negative impacts on landscape connectivity and animal movement patterns. Such impacts are likely to be particularly important for wide-ranging species, such as the African wild dog Lycaon pictus, which requires large areas of continuous habitat to fulfil its resource requirements. Laikipia County in northern Kenya is an important area for wild dogs but new wildlife fences are increasingly being built in this ecosystem. Using a long-term dataset from the area's free-ranging wild dog population, we evaluated the effect of wildlife fence structure on the ability of wild dogs to cross them. The extent to which fences impeded wild dog movement differed between fence designs, although individuals crossed fences of all types. Purpose-built fence gaps increased passage through relatively impermeable fences. Nevertheless, low fence permeability can lead to packs, or parts of packs, becoming trapped on the wrong side of a fence, with consequences for population dynamics. Careful evaluation should be given to the necessity of erecting fences; ecological impact assessments should incorporate evaluation of impacts on animal movement patterns and should be undertaken for all large-scale fencing interventions. Where fencing is unavoidable, projects should use the most permeable fencing structures possible, both in the design of the fence and including as many purpose-built gaps as possible, to minimize impacts on wide-ranging wildlife.


2021 ◽  
pp. 1-12
Author(s):  
Morgane Allanic ◽  
Misato Hayashi ◽  
Takeshi Furuichi ◽  
Tetsuro Matsuzawa

Grooming site preferences have been relatively well studied in monkey species in order to investigate the function of social grooming. They are not only influenced by the amount of ectoparasites, but also by different social variables such as the dominance rank between individuals or their levels of affiliation. However, studies on this topic mainly come from monkey species, with almost no report on great apes. This study aimed to explore whether body site and body orientation preferences during social grooming show species-specific differences (bonobos vs. chimpanzees) and environment-specific differences (captivity vs. wild). Results showed that bonobos groomed the head, the front and faced each other more often than chimpanzees, while chimpanzees groomed the back, anogenitals and more frequently in face-to-back positions. Moreover, captive individuals were found to groom facing one another more often than wild ones, whereas wild individuals groomed the back and in face-to-back positions more. While future studies should expand their scope to include more populations per condition, our preliminary 2 by 2 comparison study highlights the influence of (i) species-specific social differences such as social tolerance, social attention and facial communication, and (ii) socioenvironmental constraints such as risk of predation, spatial crowding and levels of hygiene, that might be the two important factors determining the grooming patterns in two <i>Pan</i>species.


Mammalia ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Brian Keane ◽  
Phillip J. Long ◽  
Yasmeen Fleifil ◽  
Nancy G. Solomon

AbstractBehavioral changes that reduce the risk of predation in response to predator-derived odor cues are widespread among mammalian taxa and have received a great deal of attention. Although voles of the genus Microtus are staples in the diet of many mammalian predators, including domestic cats (Felis catus), there are no previous studies on vole space utilization and activity levels in response to odor cues from domestic cats. Therefore, the objective of our study was to investigate responses of adult prairie voles (Microtus ochrogaster) living in semi-natural habitats to odor cues from domestic cat excreta. Contrary to expectations, neither adult males or females showed significant changes in space use or willingness to enter traps in response to cat odors. One hypothesis to explain our results are that prairie voles have not co-evolved with domestic cats long enough to respond to their odors. Other possible explanations include whether levels of odors in the environment were sufficient to trigger a response or that the perceived risk of predation from odor cues alone did not outweigh relative costs of changing space use and activity levels. Future studies should consider multiple factors when determining what cues are sufficient to elicit antipredatory behavior.


Sign in / Sign up

Export Citation Format

Share Document