Differential effects of predation risk and competition over vigilance variables and feeding success in Eurasian siskins (Carduelis spinus)
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Many investigations have studied the effects of predation risk and competition over vigilance and feeding success, but they have proven to be difficult to discriminate. Moreover, none of the studies that have avoided the confusion has considered all the vigilance variables, food intake rate and time spent in the foraging patch. In this study, we designed an experiment with Eurasian siskins Carduelis spinus foraging on three bird table feeders: one with low predation risk and competition, one with low predation risk and high competition and one with high predation risk and intermediate competition. Birds responded to increasing interference competition by increasing mean scan durations (probably due to the birds having to be vigilant for both other flock members and predators) and maintaining the length of mean inter-scan durations, while they responded to increasing predation risk by reducing mean inter-scan durations (probably in order to detect the predator sooner) while maintaining similar length of mean scan durations. Birds were often ejected from the feeder or departed because of disturbances, so time spent on feeders was reduced both because of competition and predation risk. Pecking rates were affected by competition but not by predation risk. Our results clearly show that birds vigilance strategy while foraging might be very different when they are mainly concerned with scanning for predators or when they primarily monitor competing flock companions. In addition, they stress the importance of recording all the vigilance and feeding variables when studying the effect of ecological factors over the foraging behaviour of birds.
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-
Baker D.J., Stillman R.A., Smart S.L., Bullock J.M., Norris K.J. (2011). Are the costs of routine vigilance avoided by granivorous foragers? — Funct. Ecol. 25: 617-627.
-
Barnard C.J. (1980). Flock feeding and time budgets in the house sparrow (Passer domesticus L.). — Anim. Behav. 28: 295-309.
-
Barnard C.J., Stephens H. (1983). Costs and benefits of single and mixed species flocking in fieldfares (Turdus pilaris) and redwings (T. iliacus). — Behaviour 84: 91-123.
-
Barta Z., Liker A., Monus F. (2004). The effects of predation risk on the use of social foraging tactics. — Anim. Behav. 67: 301-308.
-
Beauchamp G. (1998). The effect of group size on mean food intake rate in birds. — Biol. Rev. Camb. Philos. 73: 449-472.
-
Beauchamp G., Livoreil B. (1997). The effect of group size on vigilance and feeding rate in spice finches (Lonchura punctulata). — Can. J. Zool. 75: 1526-1531.
-
Beauchamp G. (2008). What is the magnitude of the group-size effect on vigilance? — Behav. Ecol. 19: 1361-1368.
-
Bednekoff P.A., Lima S.L. (2002). Why are scanning patterns so variable? An overlooked question in the study of anti-predator vigilance. — J. Avian Biol. 33: 143-149.
-
Bekoff M. (1995). Vigilance, flock size, and flock geometry — information gathering by western evening grosbeaks (Aves, Fringillidae). — Ethology 99: 150-161.
-
Caraco T., Martindale S., Pulliam H.R. (1980a). Avian flocking in the presence of a predator. — Nature 285: 400-401.
-
Caraco T., Martindale S., Pulliam H.R. (1980b). Avian time budgets and distance to cover. — Auk 97: 872-875.
-
Carrascal L.M., Alonso C.L. (2006). Habitat use under latent predation risk. A case study with wintering forest birds. — Oikos 112: 51-62.
-
Carrascal L.M., Moreno E. (1992a). Proximal costs and benefits of heterospecific social foraging in the great tit, Parus major. — Can. J. Zool. 70: 1947-1952.
-
Carrascal L.M., Moreno E. (1992b). Scanning behavior and spatial niche. — J. Ornithol. 133: 73-77.
-
Carrascal L.M., Alonso J.C., Alonso J.A. (1990). Aggregation size and foraging behavior of white storks Ciconia ciconia during the breeding season. — Ardea 78: 399-404.
-
Cassini M.H. (1991). Foraging under predation risk in the wild guinea pig Cavia aperea. — Oikos 62: 20-24.
-
Cresswell W. (1997). Interference competition at low competitor densities in blackbirds Turdus merula. — J. Anim. Ecol. 66: 461-471.
-
Cresswell W., Lind J., Kaby U., Quinn J.L., Jakobsson S. (2003a). Does an opportunistic predator preferentially attack nonvigilant prey? — Anim. Behav. 66: 643-648.
-
Cresswell W., Quinn J.L., Whittingham M.J., Butler S. (2003b). Good foragers can also be good at detecting predators. — Proc. Roy. Soc. Lond. B: Biol. 270: 1069-1076.
-
Desportes J.P., Metcalfe N.B., Popp J.W., Meyer R.M., Gallo A., Cezilly F. (1990). The predictability and patterns of vigilant behavior. — Behav. Process. 22: 41-46.
-
Domenech J., Senar J.C. (1997). Trapping methods can bias age ratio in samples of passerine populations. — Bird Stud. 44: 348-354.
-
Ekman J. (1987). Exposure and time use in willow tit flocks: the cost of subordination. — Anim. Behav. 35: 445-452.
-
Elgar M.A. (1986). The establishment of foraging flocks in house sparrows: risk of predation and daily temperature. — Behav. Ecol. Sociobiol. 19: 433-438.
-
Elgar M.A. (1987). Food-intake rate and resource availability: flocking decisions in house sparrows. — Anim. Behav. 35: 1168-1176.
-
Elgar M.A. (1989). Predator vigilance and group size in mammals and birds: a critical review of the empirical evidence. — Biol. Rev. Camb. Philos. 64: 13-33.
-
Elgar M.A., Burren P.J., Posen M. (1984). Vigilance and perception of flock size in foraging house sparrows (Passer domesticus L.). — Behaviour 90: 215-223.
-
Fernandez-Juricic E., Erichsen J.T., Kacelnik A. (2004). Visual perception and social foraging in birds. — Trends Ecol. Evol. 19: 25-31.
-
Fernandez-Juricic E., Smith R., Kacelnik A. (2005). Increasing the costs of conspecific scanning in socially foraging starlings affects vigilance and foraging behaviour. — Anim. Behav. 69: 73-81.
-
Fernandez-Juricic E., Beauchamp G., Bastain B. (2007). Group size and distance to neighbour effects on feeding and vigilance in brown headed cowbirds. — Anim. Behav. 73: 771-778.
-
Fritz H., Guillemain M., Durant D. (2002). The cost of vigilance for intake rate in the mallard (Anas platyrhynchos): an approach through foraging experiments. — Ethol. Ecol. Evol. 14: 91-97.
-
Gauvin S., Giraldeau L.A. (2004). Nutmeg mannikins (Lonchura punctulata) reduce their feeding rates in response to simulated competition. — Oecologia 139: 150-156.
-
Giraldeau L.A. (2008). Social foraging. — In: Behavioural ecology: an evolutionary perspective on behaviour ( Danchin E., Giraldeau L.A., Cezilly F., eds). Oxford University Press, Oxford, p. 257-283.
-
Gluck E. (1986). Flock size and habitat-dependent food and energy intake of foraging goldfinches. — Oecologia 71: 149-155.
-
Hart A., Lendrem D.W. (1984). Vigilance and scanning patterns in birds. — Anim. Behav. 32: 1216-1224.
-
Johnson C.A., Giraldeau L.A., Grant J.W.A. (2001). The effect of handling time on interference among house sparrows foraging at different seed densities. — Behaviour 138: 597-614.
-
Johnson C.A., Grant J.W.A., Giraldeau L.A. (2004). The effect of patch size and competitor number on aggression among foraging house sparrows. — Behav. Ecol. 15: 412-418.
-
Knight R.L., Skagen S.K. (1988). Agonistic asymmetries and the foraging ecology of bald eagles. — Ecology 69: 1188-1194.
-
Knight S.K., Knight R.L. (1986). Vigilance patterns of bald eagles feeding in groups. — Auk 103: 263-272.
-
Kotler B.P., Brown J.S., Bouskila A. (2004). Apprehension and time allocation in gerbils: the effects of predatory risk and energetic state. — Ecology 85: 917-922.
-
Lazarus J., Symonds M. (1992). Contrasting effects of protective and obstructive cover on avian vigilance. — Anim. Behav. 43: 519-521.
-
Lendrem D.W. (1983). Predation risk and vigilance in the blue tit (Parus caeruleus). — Behav. Ecol. Sociobiol. 14: 9-13.
-
Lima S.L. (1987). Vigilance while feeding and its relation to the risk of predation. — J. Theor. Biol. 124: 303-316.
-
Lima S.L. (1995). Collective detection of predatory attack by social foragers: fraught with ambiguity? — Anim. Behav. 50: 1097-1108.
-
Lima S.L., Dill L.M. (1990). Behavioral decisions made under the risk of predation: a review and prospectus. — Can. J. Zool. 68: 619-640.
-
Lima S.L., Wiebe K.L., Dill L.M. (1987). Protective cover and the use of space by finches: is closer better? — Oikos 50: 225-230.
-
Lima S.L., Zollner P.A., Bednekoff P.A. (1999). Predation, scramble competition, and the vigilance group size effect in dark-eyed juncos (Junco hyemalis). — Behav. Ecol. Sociobiol. 46: 110-116.
-
Newman J.A., Recer G.M., Zwicker S.M., Caraco T. (1988). Effects of predation hazard on foraging “constraints”: patch-use strategies in grey squirrels. — Oikos 53: 93-97.
-
Petit D.R., Bildstein K.L. (1987). Effect of group size and location within the group on the foraging behavior of white ibises. — Condor 89: 602-609.
-
Powell G.V.N. (1974). Experimental analysis of social value of flocking by starlings (Sturnus vulgaris) in relation to predation and foraging. — Anim. Behav. 22: 501-505.
-
Poysa H. (1994). Group foraging, distance to cover and vigilance in the teal, Anas crecca. — Anim. Behav. 48: 921-928.
-
Roberts G. (1995). A real-time response of vigilance behavior to changes in group size. — Anim. Behav. 50: 1371-1374.
-
Sadedin S.R., Elgar M.A. (1998). The influence of flock size and geometry on the scanning behaviour of spotted turtle doves, Streptopelia chinensis. — Aust. J. Ecol. 23: 177-180.
-
Saino N. (1994). Time budget variation in relation to flock size in carrion crows, Corvus corone corone. — Anim. Behav. 47: 1189-1196.
-
Sansom A., Cresswell W., Minderman J., Lind J. (2008). Vigilance benefits and competition costs in groups: do individual redshanks gain an overall foraging benefit? — Anim. Behav. 75: 1869-1875.
-
Scannell J., Roberts G., Lazarus J. (2001). Prey scan at random to evade observant predators. — Proc. Roy. Soc. Lond. B: Biol. 268: 541-547.
-
Schmaltz G. (2001). Scanning-group-size effect in flocks of house sparrows: quantifying the contribution of competition and anti-predatory vigilance. PhD Master of Science thesis, Concordia University, Montreal, QC.
-
Senar J.C., Copete J.L., Metcalfe N.B. (1990). Dominance relationships between resident and transient wintering siskins. — Ornis Scand. 21: 129-132.
-
Senar J.C., Burton P.J.K., Metcalfe N.B. (1992). Variation in the nomadic tendency of a wintering finch Carduelis spinus and its relationship with body condition. — Ornis Scand. 23: 63-72.
-
Senar J.C., Camerino M., Copete J.L., Metcalfe N.B. (1993). Variation in black bib of the Eurasian siskin (Carduelis spinus) and its role as a reliable badge of dominance. — Auk 110: 924-927.
-
Slotow R. (1996). Aggression in white-crowned sparrows: effects of distance from cover and group size. — Condor 98: 245-252.
-
Slotow R., Coumi N. (2000). Vigilance in bronze mannikin groups: the contributions of predation risk and intra-group competition. — Behaviour 137: 565-578.
-
Waite T.A. (1987). Vigilance in the white-breasted nuthatch: effects of dominance and sociality. — Auk 104: 429-434.
-
Whittingham M.J., Butler S.J., Quinn J.L., Cresswell W. (2004). The effect of limited visibility on vigilance behaviour and speed of predator detection: implications for the conservation of granivorous passerines. — Oikos 106: 377-385.
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Differential effects of predation risk and competition over vigilance variables and feeding success in Eurasian siskins (Carduelis spinus)
In: BehaviourSearch for other papers by Jordi Pascual in
Current site
Google Scholar
PubMed
Search for other papers by Juan Carlos Senar in
Current site
Google Scholar
PubMed
Many investigations have studied the effects of predation risk and competition over vigilance and feeding success, but they have proven to be difficult to discriminate. Moreover, none of the studies that have avoided the confusion has considered all the vigilance variables, food intake rate and time spent in the foraging patch. In this study, we designed an experiment with Eurasian siskins Carduelis spinus foraging on three bird table feeders: one with low predation risk and competition, one with low predation risk and high competition and one with high predation risk and intermediate competition. Birds responded to increasing interference competition by increasing mean scan durations (probably due to the birds having to be vigilant for both other flock members and predators) and maintaining the length of mean inter-scan durations, while they responded to increasing predation risk by reducing mean inter-scan durations (probably in order to detect the predator sooner) while maintaining similar length of mean scan durations. Birds were often ejected from the feeder or departed because of disturbances, so time spent on feeders was reduced both because of competition and predation risk. Pecking rates were affected by competition but not by predation risk. Our results clearly show that birds vigilance strategy while foraging might be very different when they are mainly concerned with scanning for predators or when they primarily monitor competing flock companions. In addition, they stress the importance of recording all the vigilance and feeding variables when studying the effect of ecological factors over the foraging behaviour of birds.
| All Time | Past 365 days | Past 30 Days | |
|---|---|---|---|
| Abstract Views | 603 | 107 | 10 |
| Full Text Views | 115 | 15 | 0 |
| PDF Views & Downloads | 183 | 29 | 0 |
