Take only pictures, leave only… Cameras influence marmot vigilance but not perceptions of risk

Vulnerable Species ◽

Species Ranges ◽

Perceptions Of Risk ◽

Flight Initiation ◽

Subsequent Risk

Ecotourism promotes conservation efforts while also allowing for low impact observation of wildlife. Many ecotourists photograph wildlife and photography plays an important role in focusing the public’s attention on nature. Although photography is commonly believed to be a low impact activity, how the visual stimulus of a camera influences wildlife remains unknown. Since animals are known to fear eyes pointed towards them, we predicted that a camera with a large zoom lens would increase animal’s vigilance levels. Using yellow-bellied marmots (Marmota flaviventer) as a mammalian model, and adopting a behavioural approach to identify how marmots responded to cameras, we experimentally quantified vigilance and flight initiation distance towards humans when marmots were approached with and without a camera. While a camera was pointed at an individual, marmots allocated less time to searching predators and increased time to looking at the observer than they did without a camera. However, whether a camera was pointed at a marmot or not had no effect on the distance the marmot flushed. Our results indicated that cameras distracted marmots but did not influence subsequent risk assessment (i.e., flight initiation distance); marmots may be curious about cameras but were not threatened by them. Capturing animals’ attentions reduces searching for predators and may increase the vulnerability to predation. Therefore, regulating photography in locations where predation risk is high or vulnerable species ranges’ overlap with humans may be required to reduce photography’s impact on wildlife.

Optimal escape theory predicts escape behaviors beyond flight initiation distance: risk assessment and escape by striped plateau lizards Sceloporus virgatus

Current Zoology ◽

10.1093/czoolo/55.2.123 ◽

2009 ◽

Vol 55 (2) ◽

pp. 123-131 ◽

Cited By ~ 32

Author(s):

William E. Cooper

Keyword(s):

Risk Factors ◽

Risk Assessment ◽

Predation Risk ◽

Risk Levels ◽

Escape Theory ◽

Growing Body ◽

Sceloporus Virgatus ◽

Escape Behaviors ◽

Abstract Escape theory predicts that flight initiation distance (FID = distance between predator and prey when escape begins) is longer when risk is greater and shorter when escape is more costly. A few tests suggest that escape theory applies to distance fled. Escape models have not addressed stochastic variables, such as probability of fleeing and of entering refuge, but their economic logic might be applicable. Experiments on several risk factors in the lizard Sceloporus virgatus confirmed all predictions for the above escape variables. FID was greater when approach was faster and more direct, for lizards on ground than on trees, for lizards rarely exposed to humans, for the second of two approaches, and when the predator turned toward lizards rather than away. Lizards fled further during rapid and second consecutive approaches. They were more likely to flee when approached directly, when a predator turned toward them, and during second approaches. They were more likely to enter refuge when approached rapidly. A novel finding is that perch height in trees was unrelated to FID because lizards escaped by moving out of sight, then moving up or down unpredictably. These findings add to a growing body of evidence supporting predictions of escape theory for FID and distance fled. They show that two probabilistic aspects of escape are predictable based on relative predation risk levels. Because individuals differ in boldness, the assessed optimal FID and threshold risks for fleeing and entering refuge are exceeded for an increasing proportion of individuals as risk increases.

Crypsis influences escape decisions in the Round-tailed Horned Lizard (Phrynosoma modestum)

Canadian Journal of Zoology ◽

10.1139/z10-068 ◽

2010 ◽

Vol 88 (10) ◽

pp. 1003-1010 ◽

Cited By ~ 10

Author(s):

William E. Cooper, ◽

Wade C. Sherbrooke

Keyword(s):

Body Temperature ◽

Predation Risk ◽

Upright Posture ◽

Lower Body ◽

Running Speed ◽

Predator Prey ◽

Sandy Area ◽

Lower Body Temperature ◽

Flight initiation distance (predator–prey distance when escape begins) increases as predation risk increases. Prey should have longer flight initiation distance when their background, movement, or current posture reduces crypsis. Flight initiation distance of ectotherms may increase at lower body temperature to compensate for slower running speed. However, for cryptic prey, fleeing might increase the probability of being detected. The Round-tailed Horned Lizard ( Phrynosoma modestum Girard, 1852) is eucryptic and resembles small stones. We predicted that flight initiation distance by P. modestum is shorter among stones than on uniform sand. Because movement and upright posture disrupt crypsis, we predicted that flight initiation distance is greater after movement and when standing than when still and lying on the ground. As predicted, flight initiation distances were shorter on a rocky than sandy area, when lying flat than standing, and while immobile than after moving. We measured running speed and flight initiation distance to determine relationships among body temperature, speed, and escape decisions. Running speed and flight initiation distance were reduced at lower body temperature, suggesting that crypsis reinforced by immobility is more advantageous than longer flight initiation distance for cool, slow lizards. The lizards adjusted escape decisions to current effectiveness of crypsis and escape ability.

Dynamic Risk Assessment: Prey Rapidly Adjust Flight Initiation Distance to Changes in Predator Approach Speed

Ethology ◽

10.1111/j.1439-0310.2006.01240.x ◽

2006 ◽

Vol 112 (9) ◽

pp. 858-864 ◽

Cited By ~ 36

Author(s):

William E. Cooper

Keyword(s):

Risk Assessment ◽

Dynamic Risk ◽

Approach Speed ◽

Dynamic Risk Assessment ◽

Escape behaviour in the leopard lizard (Gambelia wislizenii): effects of starting distance and sex

Amphibia-Reptilia ◽

10.1163/15685381-00003054 ◽

2016 ◽

Vol 37 (3) ◽

pp. 320-324 ◽

Cited By ~ 1

Author(s):

Faelan Jacobson ◽

Grace Garrison ◽

Jacob Penner ◽

João Zecchini Gebin ◽

Maria Eifler ◽

...

Keyword(s):

Risk Assessment ◽

Decision Making ◽

Resource Use ◽

Environmental Variables ◽

Flight Distance ◽

Ecological Role ◽

Escape Behaviour ◽

Behavioural Responses ◽

Predation risk influences decision making, escape behaviour, and resource use. Risk assessment and behavioural responses to predation can depend on demographic and environmental factors. We studied the escape behaviour of the long-nosed leopard lizard (Gambelia wislizenii) when approached by a human predator (= “simulated predator”), analysing flight initiation distance (FID) and flight distance (FD) relative to demographic and environmental variables. Starting distance (SD) of the simulated predator and orientation of prey lizards relative to the simulated predator influenced FID, but body size of the prey lizard did not. Sex interacted with SD to affect FID. Females lengthened their FIDs as SD increased, while male FID was unrelated to SD. Flight distance increased with increasing SD. Gambelia wislizenii’s ecological role as an ambush predator may explain their escape behaviour; reproductive status potentially affected the interaction between sex and SD.

Beyond optimal escape theory: microhabitats as well as predation risk affect escape and refuge use by the phrynosomatid lizard Sceloporus virgatus

Behaviour ◽

10.1163/156853907781890940 ◽

2007 ◽

Vol 144 (10) ◽

pp. 1235-1254 ◽

Cited By ~ 35

Author(s):

Dawn Wilson ◽

William Cooper

Keyword(s):

Risk Factors ◽

Individual Differences ◽

Predation Risk ◽

Refuge Use ◽

Escape Theory ◽

Sceloporus Virgatus ◽

AbstractEscape studies often focus on one variable, but tactics and refuge use vary with microhabitats, exposure, distance to refuge, and temperature. We studied these effects and effects of microhabitats and risk factors (distance from refuge, temperature) on flight initiation distance (FID, distance between predator and prey when escape begins) and distance fled (DF) in the lizard Sceloporus virgatus. FID increased as distance to refuge increased and temperature decreased. DF increased as FID increased, supporting the hypothesis that individual differences in boldness are consistent among encounter phases. Refuges were rock crevices, trees, logs, and grass clumps. Interhabitat differences in FID and DF matched those in distance to refuge. FID was longer for lizards on rocks and ground than trees due to proximity to and use of refuge. Lizards on trees rarely changed microhabitats, moving to the far side and unpredictably up or down. Lizards on slopes fled long distances up slopes. Most lizards on rocks entered crevices or switched microhabitats. Lizards on ground usually changed microhabitats. Optimal escape theory accurately predicted effects of risk on FID, but initial microhabitats and final microhabitats and refuges affected tactics, FID and DF. DF was affected by risk, being longer when lizards remained visible.

Predation risk, escape and refuge use by mountain spiny lizards (Sceloporus jarrovii)

Amphibia-Reptilia ◽

10.1163/156853810791769419 ◽

2010 ◽

Vol 31 (3) ◽

pp. 363-373 ◽

Cited By ~ 8

Author(s):

Arián Avalos ◽

William Cooper, Jr.

Keyword(s):

Risk Factors ◽

Predation Risk ◽

Additive Effects ◽

Refuge Use ◽

Economic Theories ◽

Approach Speed ◽

Theoretical Predictions ◽

Expected Fitness ◽

AbstractEconomic theories of antipredatory behavior take into account expected fitness losses and gains to predict escape decisions. Prey at greater risk are predicted to have longer flight initiation distance (= distance from predator when escape begins), flee farther, be more likely to enter refuge, and have longer hiding time (= time between entering and exiting refuge). We simulated predators to study effects of risk factors in the lizard Sceloporus jarrovii. Flight initiation distance, distance fled and probability of entering refuge increased with approach speed. Flight initiation distance increased additively with increases in speed and directness of approach. Lizards habituated to human presence had shorter flight initiation distances than unhabituated lizards. As predicted from greater threat posed by a persistent predator, flight initiation distance and hiding time were longer after the second of two approaches. Fleeing was more likely when an investigator stood nearby and turned toward them than when farther way or turned away. These findings verify theoretical predictions of escape and refuge use for several risk factors and most are consistent with those for other lizards. However, speed and directness of approach had additive effects in S. jarrovii, but interacted in other species. Another novel finding was a small interaction between individual investigator and directness of approach. Although outcomes of tests of escape and refuge use theories consistently confirm qualitative predictions, quantitative comparisons between studies by different investigators may have limited value unless information is available about relative responses by prey to each investigator.

Consistency in the flight and visual orientation distances of habituated chacma baboons after an observed leopard predation. Do flight initiation distance methods always measure perceived predation risk?

Ecology and Evolution ◽

10.1002/ece3.8237 ◽

2021 ◽

Author(s):

Andrew T. L. Allan ◽

Annie L. Bailey ◽

Russell A. Hill

Keyword(s):

Predation Risk ◽

Visual Orientation ◽

Distance Methods ◽

Chacma Baboons ◽

Perceived Predation Risk ◽

Vivid birds do not initiate flight sooner despite their potential conspicuousness

Current Zoology ◽

10.1093/czoolo/61.4.773 ◽

2015 ◽

Vol 61 (4) ◽

pp. 773-780 ◽

Cited By ~ 9

Author(s):

Nicholai M. Hensley ◽

Jonathan P. Drury ◽

Theodore Garland ◽

Daniel T. Blumstein

Keyword(s):

Risk Assessment ◽

Body Mass ◽

Experimental Approach ◽

Phylogenetic Relatedness ◽

Explained Variation ◽

Abstract The distance from an approaching threat at which animals initiate flight -- flight-initiation distance (FID) -- is a sensitive metric of variation in risk, but the effects on FID associated with the risk of possessing highly detectable external coloration are unknown. We tested whether variation in the degree of plumage vividness in birds explained variation in flight-initiation distance. After controlling for body mass, the distance at which the experimental approach began, and phylogenetic relatedness, plumage vividness was not a predictor of FID. Contrary to the expectation that vividness affects risk, and therefore risk assessment, these results suggest that birds do not compensate for greater visual conspicuousness by fleeing sooner from approaching threats.

Relating flight initiation distance in birds to tropical dry forest restoration

Zoologia (Curitiba) ◽

10.3897/zoologia.35.e12642 ◽

2018 ◽

Vol 35 ◽

pp. 1-6

Author(s):

Marcela Osorio-Beristain ◽

Angeles Rodríguez ◽

Cristina Martínez-Garza ◽

Raúl Ernesto Alcalá

Keyword(s):

Predation Risk ◽

Vegetation Cover ◽

Forest Restoration ◽

Restoration Ecology ◽

Tropical Dry Forest ◽

Dry Forest ◽

Foraging Strategies ◽

Perceived Predation Risk ◽

Flight initiation distance (FID), defined as the distance at which an individual flees from an approaching predator, might depend on how the individual perceives the risk of being predated. Using a standardized walking approach method on focal bird individuals, we investigated whether different levels of vegetation cover (habitat) influence the perception of predation risk. To do this, we worked in an area of tropical dry forest in central Mexico that is currently part of a restoration ecology experiment. We hypothesized that restoration decreases individual’s predation risk perception by increasing the complexity of the vegetation cover. The escape responses of three tropical birds with different diets and foraging strategies were also contrasted. There was no effect of habitat on FID, suggesting that birds in both habitats perceived predation risk in a similar manner. There was, however, a difference in FID among species: the Golden-cheeked Woodpecker tolerated closer human presence before flight than the Inca Dove and Streak-backed Oriole. This difference is likely due to the use of an alternative avoidance strategy of this species, which uses trunks for hiding. To decrease birds’ perceived predation risk, restoration intervention plans should include a mosaic of larger excluded plots located near relatively well-conserved sites to increase the area covered by vegetation.