Predicting multi-predator risk to elk (Cervus canadensis) using scats: Are migrant elk exposed to different predation risk?

There is evidence that prey can perceive the risk of predation and alter their behaviour in response, resulting in changes in spatial distribution and potential fitness consequences. Previous approaches to mapping predation risk quantify predator space use to estimate potential predator-prey encounters, yet this approach does not account for successful predator attacks resulting in prey mortality. An exception is a prey kill-site, which reflects an encounter resulting in mortality, but obtaining these data can be expensive and requires time to accumulate adequate sample sizes. We illustrate an alternative approach using predator scat locations and their contents to quantify spatial predation risk for elk (Cervus canadensis) from multiple predators in Alberta, Canada. We combined predictions of scat-based resource selection functions for bears (Ursus arctos/U. americanus), cougars (Puma concolor), coyotes (Canis latrans), and wolves (C. lupus) based on scat-detection dog surveys with predictions for the probability that a predator-specific scat in a location contained elk. We evaluated our approach by comparing predictions to a predation risk model developed from elk kill sites and applied it to describing spatial patterns in predation risk that were consistent with changes in the distribution of elk over the past decade. We found a strong correlation between risk predicted by kill sites and risk predicted by our approach (r = 0.98, P < 0.001). There was a spatial pattern to predation risk, where elk that migrated east of their winter range were exposed to highest risk from cougars, non-migratory elk were exposed to high risk from wolves and bears, and risk to elk that migrated west of their winter range into protected areas was high only from bears. The patterns in predator risk were consistent with changes in the migratory tactics in this population. The scat-based approach we present permits broad-scale inferences on predation risk for prey.

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Predicting multi-predator risk to elk (Cervus canadensis) using scats: Are migrant elk exposed to different predation risk?

10.22541/au.162082168.86615974/v2 ◽

2021 ◽

Author(s):

Kara MacAulay ◽

Eric Spilker ◽

Jodi Berg ◽

Mark Hebblewhite ◽

Evelyn Merrill

Keyword(s):

Predation Risk ◽

Ursus Arctos ◽

Risk Model ◽

Puma Concolor ◽

Potential Predator ◽

Multiple Predators ◽

Winter Range ◽

Risk Of Predation ◽

Cervus Canadensis ◽

Predator Risk

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Do changes in reef habitats influence relative predation risk on the juvenile Australasian spiny lobster, Jasus edwardsii (Hutton, 1875)?

Crustaceana ◽

10.1163/15685403-00003447 ◽

2015 ◽

Vol 88 (7-8) ◽

pp. 839-856 ◽

Cited By ~ 4

Author(s):

J. Hesse ◽

J. A. Stanley ◽

A. G. Jeffs

Keyword(s):

Predation Risk ◽

Spatial Scales ◽

Spiny Lobster ◽

Habitat Type ◽

Small Spatial Scale ◽

Important Species ◽

Early Juvenile ◽

Risk Of Predation ◽

Jasus Edwardsii ◽

Commercially Important

Kelp habitats are in decline in many temperate coastal regions of the world due to climate change and expansion of populations of grazing urchins. The loss of kelp habitat may influence the vulnerability to predators of the juveniles of commercially important species. In this study relative predation rates for kelp versus barren reef habitat were measured for early juvenile Australasian spiny lobster, Jasus edwardsii (Hutton, 1875), on the northeastern coast of New Zealand using tethering methods. Variation in assemblages of predators over small spatial scales appeared to be more important for determining the relative predation of lobsters, regardless of habitat type. Therefore, the assessment of relative predation risk to early juvenile lobsters between kelp and barren habitats will require more extensive sampling at a small spatial scale, as well as a specific focus on sampling during crepuscular and nocturnal periods when these lobsters are most at risk of predation.

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Behavioural responses of voles to simulated risk of predation by a native and an alien mustelid: an odour manipulation experiment

Wildlife Research ◽

10.1071/wr08031 ◽

2010 ◽

Vol 37 (4) ◽

pp. 273 ◽

Cited By ~ 11

Author(s):

Karen Fey ◽

Peter B. Banks ◽

Hannu Ylönen ◽

Erkki Korpimäki

Keyword(s):

Baltic Sea ◽

Predation Risk ◽

Myodes Glareolus ◽

The Baltic Sea ◽

Short Term ◽

Behavioural Responses ◽

Alien Predator ◽

Risk Of Predation ◽

The Baltic ◽

The Impact

Context. Potential mammalian prey commonly use the odours of their co-evolved predators to manage their risks of predation. But when the risk comes from an unknown source of predation, odours might not be perceived as dangerous, and anti-predator responses may fail, except possibly if the alien predator is of the same archetype as a native predator. Aims. In the present study we examined anti-predator behavioural responses of voles from the outer archipelagos of the Baltic Sea, south-western Finland, where they have had no resident mammalian predators in recent history. Methods. We investigated responses of field voles (Microtus agrestis) to odours of native least weasels (Mustela nivalis) and a recently invading alien predator, the American mink (Mustela vison), in laboratory. We also studied the short-term responses of free-ranging field voles and bank voles (Myodes glareolus) to simulated predation risk by alien mink on small islands in the outer archipelago of the Baltic Sea. Key results. In the laboratory, voles avoided odour cues of native weasel but not of alien mink. It is possible that the response to mink is a context dependent learned response which could not be induced in the laboratory, whereas the response to weasel is innate. In the field, however, voles reduced activity during their normal peak-activity times at night as a response to simulated alien-mink predation risk. No other shifts in space use or activity in safer microhabitats or denser vegetation were apparent. Conclusions. Voles appeared to recognise alien minks as predators from their odours in the wild. However, reduction in activity is likely to be only a short-term immediate response to mink presence, which is augmented by longer-term strategies of habitat shift. Because alien mink still strongly suppresses vole dynamics despite these anti-predator responses, we suggest that behavioural naiveté may be the primary factor in the impact of an alien predator on native prey. Implications. Prey naiveté has long been considered as the root cause of the devastating impacts of alien predators, whereby native prey simply fail to recognise and respond to the novel predation risk. Our results reveal a more complex form of naiveté whereby native prey appeared to recognise alien predators as a threat but their response is ultimately inadequate. Thus, recognition alone is unlikely to afford protection for native prey from alien-predator impacts. Thus, management strategies that, for example, train prey in recognition of novel threats must induce effective responses if they are expected to succeed.

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Home Ranges and Movements of Elk (Cervus canadensis) Restored to Southern Ontario, Canada

The Canadian Field-Naturalist ◽

10.22621/cfn.v130i4.1926 ◽

2017 ◽

Vol 130 (4) ◽

pp. 320 ◽

Cited By ~ 2

Author(s):

Rick Rosatte

Keyword(s):

Home Range ◽

Home Range Size ◽

Home Ranges ◽

Winter Range ◽

The Social ◽

Cervus Canadensis ◽

Summer Range ◽

Seasonal Basis ◽

Social Units ◽

Winter Feeding

During 2000 and 2001, Elk (Cervus canadensis) were restored to the Bancroft, Ontario area. The objective of this study was to determine the home range and movements of six social units of Elk, 5–12 years after restoration, in an area of about 2500 km2 near Bancroft. Home range and movements were calculated from 40 221 Global Positioning System locations acquired from 56 collared Elk (16 bulls and 40 cows) between 2006 and 2013. Annual home ranges were found to be significantly greater (mean 110.3 km2, standard error [SE] 11.2) for Elk in areas where winter feeding by humans did not occur compared with those (mean 51.0 km2, SE 9.0) where winter feeding was prevalent. Elk in winter feeding areas had smaller ranges in winter than other seasons. On a seasonal basis, home range size was larger for Elk in areas where winter feeding did not occur; mean winter home range for Elk in non-feeding areas was 73.4 km2 (SE34.0) compared with 8.3 km2 (SE 2.6) for Elk in areas where winter feeding occurred. The 20 Elk that were monitored for multiple years exhibited home range fidelity among years. The entire range of all radio-collared Elk within the social groups studied covered 1716.4 km2 during 2006–2013. Average daily movements of Elk in the study arearanged from 1.0 to 2.1 km/day with greatest movements occurring during spring and summer. However, some Elk were capable of moving an average of 5–7km in a 12-h interval. Movements (about 5 km) to winter range occurred during October to December each year. Cows moved to calving areas in May with mean movements of Elk to spring/summer range about 6 km. Cow/calf groups moved to fall ranges by early September with mean movements of about 4 km. During the rut, mean bull movements of 16.0 km to cow groups over 1–5 days occurred in early September. Hunting of Elk during the fall of 2011 and 2012 did not appear to significantly affect the movements and dispersion of Elk in the study area.

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Gray Wolves, Canis lupus, Killed by Cougars, Puma concolor, and a Grizzly Bear, Ursus arctos, in Montana, Alberta, and Wyoming

The Canadian Field-Naturalist ◽

10.22621/cfn.v122i1.550 ◽

2008 ◽

Vol 122 (1) ◽

pp. 76 ◽

Cited By ~ 6

Author(s):

Michael D. Jimenez ◽

Valpa J. Asher ◽

Carita Bergman ◽

Edward E. Bangs ◽

Susannah P. Woodruff

Keyword(s):

United States ◽

Canis Lupus ◽

Ursus Arctos ◽

Puma Concolor ◽

Western United States ◽

Grizzly Bear ◽

Grey Wolf ◽

Gray Wolves ◽

Large Predators

Four cases where large predators caused Grey Wolf (Canis lupus) mortality are recorded. We describe two incidents of Cougars (Puma concolar) killing Wolves in Montana and one incident of a Cougar killing a Wolf in Alberta. We report the first recorded incident of a Grizzly Bear (Ursus arctos) killing a Wolf in the western United States.

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Predation Risk by Gastronomic Boom - Case Peru

Journal of Landscape Ecology ◽

10.2478/jlecol-2018-0003 ◽

2018 ◽

Vol 11 (1) ◽

pp. 100-103

Author(s):

Aldo Alvarez-Risco ◽

Jaime Delgado-Zegarra ◽

Jaime A. Yáñez ◽

Santiago Diaz-Risco ◽

Shyla Del-Aguila-Arcentales

Keyword(s):

Natural Resources ◽

Predation Risk ◽

Environmental Sustainability ◽

Natural Sources ◽

Risk Of Predation ◽

Significant Damage

Abstract The growth of tourism to Peru and the gastronomic boom with millions of people looking to taste Peruvian food is resulting in a risk of predation of natural sources necessary to make these dishes. The focus in only obtaining these ingredients can generate significant damage to the Peruvian biodiversity, so stakeholders need to develop strategies to avoid predation due to the gastronomic boom. Citizens and visitors need to play a role in protecting the natural resources and contributing to environmental sustainability.

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Developmental costs of yellow colouration in fire salamanders and experiments to test the efficiency of yellow as a warning colouration

Amphibia-Reptilia ◽

10.1163/15685381-bja10006 ◽

2020 ◽

Vol 41 (3) ◽

pp. 373-385 ◽

Cited By ~ 1

Author(s):

Barbara A. Caspers ◽

E. Tobias Krause ◽

Isabelle Hermanski ◽

Christopher Wiesbrock ◽

Friedrich-Wilhelm Kastrup ◽

...

Keyword(s):

Predation Risk ◽

Carabid Beetles ◽

Colour Pattern ◽

Natural Habitats ◽

Yellow Colour ◽

Risk Of Predation ◽

Fire Salamander ◽

Food Conditions ◽

In Fire ◽

Salamander Larvae

Abstract Warning colouration reduces predation risk by signalling or mimicking the unpleasantness of prey and therefore increases survival. We tested in two experiments the evolutionary costs and benefits of the yellow colour pattern in fire salamanders (Salamandra salamandra), which display a yellow/black colour pattern usually associated with toxic alkaloids. Our first experiment aimed to test whether the development of colouration is condition dependent and thus related to developmental costs, i.e. influenced by resource availability during the developmental process. Therefore, we reared fire salamander larvae under different nutritional conditions and compared the relative amount of yellow they developed after metamorphosis. Fire salamander larvae reared under limited food conditions had a lower proportion of yellow following metamorphosis than control larvae reared under superior food conditions. In a second experiment we tested whether the proportion of yellow has an impact on the risk of being attacked using artificial models. We tested, in salamander-free and salamander-occupied natural habitats, whether artificial clay models with different proportions of yellow and black receive different attack rates from potential predators (birds, mammals, insects). In clay models the proportion of yellow and the site had a significant effect on predation risk. Models with larger amounts of yellow had fewer bite marks from predators such as carabid beetles and birds, but only in sympatry with salamanders. In conclusion, the early expression of conspicuous colouration seems to be condition dependent and therefore potentially costly. Furthermore, the yellow colouration of fire salamanders act as a signal that potentially reduces their risk of being attacked by predators. Thus, the yellow colouration of fire salamanders seems to represent an adaptive trait that reduces the risk of predation, which can be expressed in higher quantity by individuals of a certain condition.

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SCREAMING AS A STRATEGY TO REDUCE THE PREDATION RISK INCURRED BY BEGGING?

Behaviour ◽

10.1163/156853901316924502 ◽

2001 ◽

Vol 138 (5) ◽

pp. 615-627 ◽

Cited By ~ 9

Author(s):

Keyword(s):

Predation Risk ◽

Feeding Rate ◽

Honest Signal ◽

Apparent Paradox ◽

Signalling System ◽

Comparative Analyses ◽

Risk Of Predation ◽

Food Requirement ◽

Per Se ◽

High Degree

AbstractFollowing the theory of parent-offspring conflict parents request from their offspring an honest signal of food requirement to optimally adjust feeding rate. For this purpose, offspring display a highly informative signalling system, begging vocalisation, for which the conspicuousness to predators maintains honesty, since only hungry offspring are willing to take this risk. The risk of predation incurred by begging activities challenges our understanding of how begging vocalisation could evolve towards a high degree of noisiness. A solution to this apparent paradox resides in the possibility that alongside the evolution of begging, birds also evolved strategies that reduce the risk of being depredated. Following the ornithological literature nestlings scream in the presence of a predator to frighten it, induce parents to rescue them and siblings to flee from the nest and hide in the vegetation. I therefore propose the hypothesis that nestling screaming behaviour evolved as a means of reducing the risk of predation incurred by conspicuous begging. Comparative analyses supported the prediction postulating that species in which nestlings scream in the presence of a predator produce begging calls that are more conspicuous to predators than calls of non-screaming species. This suggests that the predation cost of begging lies not only in terms of predation per se but also in the requirement of anti-predator strategies.

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Flirting with danger: predation risk interacts with male condition to influence sexual display

Behavioral Ecology ◽

10.1093/beheco/arz073 ◽

2019 ◽

Vol 30 (5) ◽

pp. 1265-1272

Author(s):

Pedro Z de Moraes ◽

Pedro Diniz ◽

Esteban Fernandez-Juricic ◽

Regina H Macedo

Keyword(s):

High Risk ◽

Predation Risk ◽

Video Recording ◽

Reproductive Value ◽

Male Response ◽

Residual Reproductive Value ◽

Display Behavior ◽

Sexual Display ◽

Male Condition ◽

Risk Of Predation

AbstractSexual signaling coevolves with the sensory systems of intended receivers; however, predators may be unintended receivers of sexual signals. Conspicuous aerial displays in some species may place males at high risk of predation from eavesdropping predators. There are three different hypotheses to explain how signaling males can deal with increased predation risk: (1) males invest in survival by decreasing signal conspicuousness; (2) males invest in reproduction by increasing signal conspicuousness; and (3) male response is condition-dependent according to his residual reproductive value. Here, we used blue-black grassquits (Volatinia jacarina) to test these hypotheses, asking whether males modify leap displays under different levels of predation risk. Grassquit males develop an iridescent nuptial plumage and spend considerable time emitting a multimodal signal: while leaping from a perch, males clap their wings above their heads and emit a high-pitched short song. We exposed males to predator and nonpredator playbacks while video recording their displays. We found interactions between predation risk and 2 male condition variables (ectoparasite infestation and proportion of nuptial plumage coverage) that influenced display behavior. Less parasitized males and those with higher proportion of nuptial plumage showed no change in display behavior, while more parasitized males and those with lower proportion of nuptial plumage increased the vigor of displays under predation risk. In other words, males with low residual reproductive value increased reproductive effort when there was a high risk of extrinsic death. Our study provides some empirical support for the terminal investment hypothesis.

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Does risk of predation influence population dynamics? Evidence from cyclic decline of snowshoe hares

Wildlife Research ◽

10.1071/wr9950115 ◽

1995 ◽

Vol 22 (1) ◽

pp. 115 ◽

Cited By ~ 129

Author(s):

D. S. Hik

Keyword(s):

Predation Risk ◽

Body Mass ◽

Female Body ◽

Population Decline ◽

Control Area ◽

High Rate ◽

Food Treatment ◽

Snowshoe Hares ◽

Risk Of Predation ◽

Female Body Mass

Like most heavily preyed-upon animals, snowshoe hares (Lepus americanus) have to balance conflicting demands of obtaining food at a high rate and avoiding predators. Adopting foraging behaviours to minimise predation risk may also lead to a decline in condition, and hence fecundity. Predictions of three hypotheses (condition constraint hypothesis, predator-avoidance constraint hypothesis, predation-sensitive foraging (PSF) hypothesis) were tested by comparing changes in the survival and condition of snowshoe hares on four experimental areas in winter during a cyclic peak and decline (1989–1993) near Kluane Lake, Yukon, Canada, where (i) predation risk was reduced by excluding terrestrial predators (FENCE), (ii) food supply was supplemented with rabbit chow ad libitum (FOOD), (iii) these two treatments were combined (FENCE+FOOD), and (iv) an unmanipulated CONTROL was used. Different pattems of survival and changes in body mass were observed in the presence and absence of terrestrial predators. On the CONTROL area, female body mass and fecundity declined, even though sufficient winter forage was apparently available in all years. A similar decrease in body mass was observed on the FOOD treatment, but only during the third year of the population decline. In contrast, female body mass remained high throughout the decline in the absence of terrestrial predators in the FENCE+FOOD and FENCE treatments. Winter survival declined on CONTROL and FENCE areas during the first year of the population decline (1991), but remained higher on FOOD until 1992 and FENCE+FOOD until 1993. These results generally supported the PSF hypothesis where terrestrial predators were present (CONTROL and FOOD grids). Where terrestrial predators were absent (FENCE and FENCE+FOOD), the results supported the alternative condition constraint hypothesis. The evidence suggests that a cascade of sublethal behavioural and physiological effects associated with increased predation risk contribute to the population decline and delayed recovery of cyclic low-phase populations of snowshoe hares.

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