Stage‐dependent puma predation on dangerous prey

Abstract

Predators likely assess their risk of injury with regards to hunting different prey types, while deciding whether to initiate an attack or to avoid dangerous prey. Risk-taking is age-, stage-and state-dependent, and foraging theory predicts that juvenile predators, individuals of lower social rank, and less-experienced predators that are hungry are among those most likely to engage dangerous prey. In carnivores that optimally hunt prey larger than themselves, however, juveniles may also select for smaller, suboptimal prey as they refine their hunting skills. Thus, in the case of predators that exhibit age-specific prey selection, there may be multiple factors influencing decision-making about prey selection. We compared puma (Puma concolor) predation on dangerous adult ungulates and safer juvenile ungulates, as well as two similar-sized rodent species: the more dangerous North American porcupine (Erethizon dorsatum) and the more vulnerable American beaver (Castor canadensis). We found that dispersing, subadult pumas with limited hunting experience and without territories avoided dangerous but optimally sized adult ungulates, and instead hunted dangerous, suboptimal porcupines more than resident, territorial adults. In contrast, there was no difference in puma predation on beavers between dispersers and residents. Small prey (e.g. not ungulates) formed a large portion of dispersing puma diets of both sexes, and this stage-dependent foraging pattern might be important in describing the ecology of the species, as well as in modeling potential dispersal habitat that could see puma expansion east in North America across hostile matrices where their primary prey has been reduced through anthropogenic effects.

Predator size and prey size–gut capacity ratios determine kill frequency and carcass production in terrestrial carnivorous mammals

“…Thus, a functional dichotomy seems to exist in carnivores, but ecologic rather than physiologic factors seem to determine whether a carnivore is a 'small prey-feeder' or a 'large prey-feeder'. This functional dichotomy may well occur within species where different individuals are specialized on different prey (Codron et al 2016), within individuals over ontogeny (Elbroch et al 2017), or in individuals between hunting events (Lumetsberger et al 2017). Observations deviating from the general pattern, such as a population of wild cats living on rabbits rather than small rodents (Malo et al 2004), or a population of wild dogs living mainly on very small ungulates (Woodroffe et al 2007), indicate that the underlying cause for the dichotomy must be sought in ecological circumstances rather than fixed physiological and behavioural adaptations.…”

Age‐specific foraging strategies among pumas, and its implications for aiding ungulate populations through carnivore control

“…IS is exhibited across diverse taxa, although its effects on predator-prey dynamics and the mechanisms that lead to divergence among individuals within a population are still under study (Araújo et al, 2011;Bolnick et al, 2003). Both extrinsic (resource availability and the influence of social groups; Darimont, Paquet, & Reimchen, 2009;Elliot-Smith, Newsome, Estes, & Tinket, 2015;Newsome et al, 2015;Robertson, McDonald, Delahay, Kelly, & Bearhop, 2015) and intrinsic factors (sex, and age and life history stage; Elliot-Smith et al, 2015;Robertson et al, 2015;Elbroch, Feltner, & Quigley, 2017) may explain IS among carnivores.…”

“…Hunting predators, however, often skews the sex-and age-structure of predator populations (Milner, Nilsen, & Andreassen, 2007), which may hold consequences for prey selection as exhibited by different sex-or age-classes of top predators. For example, younger ageclasses of African lions (Panthera leo) and pumas (Puma concolor) select for smaller suboptimal prey, as they learn the requisite skills to hunt more dangerous large prey (Elbroch et al, 2017;Hayward, Hofmeyr, O'Brien, & Kerley, 2007).…”

Habitat selection when killing primary versus alternative prey species supports prey specialization in an apex predator

“…Further research, however, is needed to better determine why predators sometimes disproportionately select alternative prey, but kill such prey opportunistically, in other systems. Dispersing pumas disproportionately select small prey (Elbroch, Feltner & Quigley, ), for example, and their prey selection may or not be influenced by habitat selection for dispersal corridors. Outcomes from such research have important implications for the management and conservation of species affected by apparent competition (Wittmer et al , ) particularly in complex multi‐species systems where kill site habitats may also be predator specific (Apps et al , ).…”