Escape strategy of Schreiber’s green lizards (Lacerta schreiberi) is determined by environment but not season or sex

Antipredator escape behaviour varies with several well-established sources of variation ranging from the physical environment to reproductive status. However, the relative roles of these sources are rarely assessed together. We measured (i) the distance to the nearest refuge that Schreiber’s green lizards, Lacerta schreiberi, maintained before an attack (refuge distance) and (ii) the distance lizards allowed a simulated predator to approach before fleeing (flight initiation distance, FID). Refuge distance was unaffected by studied variables. However, FID was positively related to refuge distance on grassy, but not on rocky substrates. Furthermore, refuge distance and escape angle interacted in a substrate-independent manner: lizards allowed predators close when refuges were close or when lizards had to flee towards the predator. In contrast, neither mating season nor sex affected FID. We suggest that the escape strategy of L. schreiberi is determined more by the physical environment than by sex or reproductive condition.

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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 ◽

Flight Initiation Distance ◽

Ecological Role ◽

Escape Behaviour ◽

Behavioural Responses ◽

Flight Initiation

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.

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Risk factors affecting escape behaviour by Puerto Rican Anolis lizards

Canadian Journal of Zoology ◽

10.1139/z06-018 ◽

2006 ◽

Vol 84 (4) ◽

pp. 495-504 ◽

Cited By ~ 24

Author(s):

W.E. Cooper

Keyword(s):

Risk Factors ◽

Puerto Rican ◽

Ground Level ◽

Flight Initiation Distance ◽

Running Speed ◽

Escape Behaviour ◽

Factors Affecting ◽

Narrow Temperature Range ◽

Approach Distance ◽

Flight Initiation

Approach distance (flight initiation distance) and escape methods depend on predation risk. I studied escape methods and effects of risk factors (temperature, perch height and orientation, conspicuousness) on approach distance in seven Puerto Rican anoles. Approach distance increased as temperature decreased in Anolis gundlachi Peters, 1876, presumably because of decreasing running speed, but not in other species (probably because of narrow temperature range). Perch height and approach distance varied inversely in four arboreal species that escape upward, positively in two grass–bush species that are more conspicuous when higher and flee downward, and were unrelated in cryptic Anolis stratulus Cope, 1861. Approach distance was shortest in cryptic A. stratulus and shorter intraspecifically in three species for partially concealed lizards and at sites providing more cover in two species. Approach distance was shorter for A. gundlachi on vertical than nonvertical perches, suggesting that ease of escape upward affects assessed risk. Escape behaviours have been proposed to vary among anole ecomorphs. Grass–bush species fled downward as proposed, or horizontally near ground level. Contrary to predictions of escape downward by trunk–ground and upward by trunk–crown anoles, all arboreal species escaped upward. Only trunk anoles were proposed to use squirreling, but species from four ecomorphs did as well.

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Risk factors and escape strategy in the grasshopper Dissosteira carolina

Behaviour ◽

10.1163/156853906778691595 ◽

2006 ◽

Vol 143 (10) ◽

pp. 1201-1218 ◽

Cited By ~ 35

Author(s):

William E. Cooper

Keyword(s):

Risk Factors ◽

Field Experiments ◽

Escape Behavior ◽

Sudden Change ◽

Flight Initiation Distance ◽

Initial Direction ◽

Escape Strategy ◽

Approach Speed ◽

Lateral Escape ◽

Flight Initiation

AbstractTo determine aspects of escape strategy by the Carolina grasshopper, Dissosteira carolina, and applicability of models of escape behavior applied primarily to vertebrates, I conducted three field experiments by simulating an approaching predator. Escape theory predicts that flight initiation distance (distance from predator when escape begins) and distance fled increase as predation risk increases. Some aspects of escape are not predicted, and theory does not identify escape strategies including several components. I examined effects of risk factors (predator approach speed, directness of approach, and repeated approach) on flight initiation distance, distance fled, and the initial direction of escape. Flight initiation distance and distance fled were predicted to increase with approach speed. Because predators approaching directly may bypass prey without detecting it, probability of fleeing and flight initiation distance were predicted to increase with directness of approach. Because a persistent predator poses greater threat, flight initiation distance and distance fled were predicted to be greater for the second of two successive approaches. All findings were consistent with predictions of the Ydenberg & Dill (1986) model, suggesting that risk assessment and escape decisions by visually oriented insects may be similar to those of vertebrates. Although escape directly away from the predator might be expected to minimize risk, most grasshoppers escaped by flying at nearly right angles to the approach path. Lateral escape may be part of an escape strategy in which dark wing colour during flight rapidly disappears upon landing. With sudden change in colour and movement, the grasshopper becomes cryptic and difficult to relocate. Lateral escape may increase difficulty of maintaining visual contact with the grasshopper until it lands. It also avoids need for further escape from a predator that continues in its initial direction.

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Conspicuousness and vestigial escape behaviour by two dendrobatid frogs, Dendrobates auratus and Oophaga pumilio

Behaviour ◽

10.1163/156853909x410946 ◽

2009 ◽

Vol 146 (3) ◽

pp. 325-349 ◽

Cited By ~ 21

Author(s):

Janalee Caldwell ◽

Laurie Vitt ◽

William Cooper

Keyword(s):

Defensive Behavior ◽

Close Approach ◽

Flight Initiation Distance ◽

Escape Behaviour ◽

Predator Prey ◽

Poison Frogs ◽

Oophaga Pumilio ◽

Approach Speed ◽

Dendrobates Auratus ◽

Flight Initiation

AbstractAposematic prey are thought to move slowly and openly near predators, but exhibit reduced escape behaviour. We studied conspicuousness and escape by aposematic poison frogs (Dendrobates auratus and Oophaga pumilio). In circles of leaf litter, observers detected poison frogs quickly. Flight initiation distance (FID, predator-prey distance when escape begins) increases with approach speed in non-cryptic palatable prey, but not for frogs in clearings, which permitted close approach. On trails frogs moved slowly into forest and FID in D. auratus increased with approach speed. Distance from cover and handling exposing predators to distastefulness may account for greater reliance on aposematism in clearings. We observed responses to a simulated predator (stick with painted face) in three conditions: not approached, approached, and touched. Latency to hop and time to exit circles decreased and exit from circles was directed further away from the approach path in the order not approached, approached, touched. Oophaga pumilio changed directions less when approached than not; many exhibited no escape behaviour. Aposematic dendrobatids move slowly near predators, but retain risk-assessment mechanisms due to occasional predation. Differences in escape between dendrobatids and palatable Craugastor frogs suggest that dendrobatid defensive behavior may have been molded to maximize the effectiveness of aposematism.

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Escape behaviour of aposematic (Oophaga pumilio) and cryptic (Craugastor sp.) frogs in response to simulated predator approach

Journal of Tropical Ecology ◽

10.1017/s0266467417000037 ◽

2017 ◽

Vol 33 (2) ◽

pp. 165-169 ◽

Cited By ~ 5

Author(s):

Annelise Blanchette ◽

Noémi Becza ◽

Ralph A. Saporito

Keyword(s):

Flight Initiation Distance ◽

Warning Signals ◽

Escape Behaviour ◽

Antipredator Strategies ◽

Oophaga Pumilio ◽

Flight Initiation

Abstract:Crypsis and aposematism are common antipredator strategies that can each be coupled with behaviours that maximize predator deterrence or avoidance. Cryptic animals employ camouflage to conceal themselves within their environment and generally rely on immobility to avoid detection by predators. Alternatively, aposematic animals tend to rely on an association between conspicuous colouration and secondary defence to deter potential predators, and tend to exhibit slow movements in response to predators. The goal of the present study was to determine how cryptic Craugastor sp. and aposematic Oophaga pumilio respond to simulated human and bird model predators. Oophaga pumilio responded more often with movement to both the human (17/22) and bird (9/25) predators than Craugastor sp. (human: 2/21; bird: 0/21). The increased movement resulted in a greater average flight initiation distance, latency to move, and distance fled in O. pumilio. These findings suggest that cryptic Craugastor sp. rely on immobility to avoid detection, whereas aposematic O. pumilio utilize movement, possibly as a mechanism to increase the visibility of their warning signals to potential predators. Furthermore, O. pumilio exhibited greater movement in response to humans, suggesting that they actively avoid trampling by large threats, rather than considering them predators.

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Effects of sex and microhabitat structure on escape behaviour in the diurnal gecko Gonatodes albogularis

Animal Biology ◽

10.1163/15707563-00002485 ◽

2016 ◽

Vol 66 (1) ◽

pp. 31-47 ◽

Cited By ~ 1

Author(s):

Moisés E. Domínguez-López ◽

Francisco J. Diego-Rasilla ◽

Ángela M. Ortega-León

Keyword(s):

Tropical Dry Forest ◽

Structural Complexity ◽

Dry Forest ◽

Microhabitat Use ◽

Flight Initiation Distance ◽

Escape Behaviour ◽

Escape Theory ◽

Microhabitat Structure ◽

The Cost ◽

Flight Initiation

Flight initiation distance is defined as the distance between a prey and an approaching predator when the prey starts to flee. Escape theory predicts that the optimal flight initiation distance is the distance where predation risk rises to the point at which it equals the cost of fleeing. Therefore, staying close to refuge and occupying microhabitats with more abundant shelters (i.e., crevices or shrubs) may allow lizards to have shorter flight initiation distance. By simulating an approaching predator, we studied the effect of microhabitat structural complexity on escape behaviour, in particular, the distance fled before stopping and final distance (predator-prey distance when the prey stops fleeing), of a small diurnal tropical gecko, the yellow-headed geckoGonatodes albogularisinhabiting a tropical dry forest. The findings indicate that refuge abundance and distance to the nearest potential refuge influence escape behaviour ofG. albogularis. In addition, we found sex differences in escape behaviour which are not explained by microhabitat use. Females had longer flight initiation distance but shorter distance fled, and longer final distances than males.

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European birds adjust their flight initiation distance to road speed limits

Biology Letters ◽

10.1098/rsbl.2013.0417 ◽

2013 ◽

Vol 9 (5) ◽

pp. 20130417 ◽

Cited By ~ 48

Author(s):

Pierre Legagneux ◽

Simon Ducatez

Keyword(s):

Habitat Structure ◽

Territory Size ◽

Speed Limit ◽

Vehicle Speed ◽

Flight Initiation Distance ◽

Speed Limits ◽

Behavioural Responses ◽

Road Speed ◽

Flight Initiation ◽

Local Speed

Behavioural responses can help species persist in habitats modified by humans. Roads and traffic greatly affect animals' mortality not only through habitat structure modifications but also through direct mortality owing to collisions. Although species are known to differ in their sensitivity to the risk of collision, whether individuals can change their behaviour in response to this is still unknown. Here, we tested whether common European birds changed their flight initiation distances (FIDs) in response to vehicles according to road speed limit (a known factor affecting killing rates on roads) and vehicle speed. We found that FID increased with speed limit, although vehicle speed had no effect. This suggests that birds adjust their flight distance to speed limit, which may reduce collision risks and decrease mortality maximizing the time allocated to foraging behaviours. Mobility and territory size are likely to affect an individuals' ability to respond adaptively to local speed limits.

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