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Flock size increases with the diversity and abundance of local predators in an avian family

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Abstract

Group living has long been viewed as an adaptation to reduce predation risk. Earlier comparative analyses provided support for the hypothesis but typically ignored variation in group size at the local scale and included proxies of predation risk rather than more direct estimates. Here, we related variation in group size at the scale of a study site in various species with the diversity and abundance of local predators. If larger groups provide protection against predators, we expected larger groups to evolve in species facing locally more diverse and abundant predators. We examined this hypothesis in one avian family, the Paridae, which are small arboreal birds that include some of the better studied species in ecology. From the literature, we gathered 275 flock size estimates from 34 species. In a phylogenetic framework and controlling for the potential confounding effect of latitude, we found that flock size increased with predation risk but only in flocks that included more than one species. We suggest that competition sets an upper limit to the size of flocks including conspecifics only. Joining flocks with other species, thus, allows individuals to increase flock size in response to higher predation risk without a substantial increase in competition. Overall, our results based on more direct estimates of predation risk provide further comparative evidence for an association between predation and the evolution of flocking in birds.

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References

  • Allee WC (1932) Animal life and social growth. William and Wilkins, Baltimore

    Google Scholar 

  • Barve S, Dhondt AA (2017) Elevational replacement of two Himalayan titmice: interspecific competition or habitat preference? J Avian Biol 48:1189–1194

    Article  Google Scholar 

  • Beauchamp G (2014) Social predation: how group living benefits predators and prey. Academic Press, New York

    Google Scholar 

  • Beauchamp G (2022) Flocking in birds is associated with diet, foraging substrate, timing of activity, and life history. Behav Ecol Sociobiol 76:74

    Article  Google Scholar 

  • Beauchamp G (2023) Susceptibility to predation varies with body mass, foraging niche, and anti-predator responses among bird species. Birds 4:73–84

    Article  Google Scholar 

  • Blumstein DT, Daniel JC (2005) The loss of anti-predator behaviour following isolation on islands. Proc R Soc Lond B Biol Sci 272:1663–1668

    Google Scholar 

  • Buskirk WH (1976) Social systems in a tropical forest avifauna. Am Nat 110:293–310

    Article  Google Scholar 

  • Chapa-Vargas L, Ceballos G, Tinajero R, Torres-Romero EJ (2019) Latitudinal effects of anthropogenic factors driving raptor species richness across the American continent. J Biogeogr 46:1948–1958

    Article  Google Scholar 

  • Chen CC, Hsieh F (2002) Composition and foraging behaviour of mixed-species flocks led by the Grey-cheeked Fulvetta in Fushan Experimental Forest, Taiwan. Ibis 144:317–330

    Article  Google Scholar 

  • Colorado Zuluaga GJ, Rodewald AD (2015) Response of mixed-species flocks to habitat alteration and deforestation in the Andes. Biol Conserv 188:72–81

    Article  Google Scholar 

  • Crook JH (1964) The evolution of social organisation and visual communication in the weaver birds (Ploceinae). Behav Supp 10:1–178

    Google Scholar 

  • Crook JH (1965) The adaptive significance of avian social organisations. Symp Zool Soc Lond 14:181–218

    Google Scholar 

  • Crook JH, Gartlan JS (1966) Evolution of primate societies. Nature 210:1200–1203

    Article  CAS  PubMed  Google Scholar 

  • Dhondt AA (2007) What drives differences between North American and Eurasian tit studies? In: Otter KA (ed) Ecology and behavior of chickadees and titmice: an integrated approach. Oxford University Press, Oxford, pp 299–310

    Chapter  Google Scholar 

  • Díaz M et al (2013) The geography of fear: A latitudinal gradient in anti-predator escape distances of birds across Europe. PLoS ONE 8:e64634

    Article  PubMed  PubMed Central  Google Scholar 

  • Dixon KL (1956) Territoriality and survival in the plain titmouse. Condor 58:169–182

    Article  Google Scholar 

  • Ekman J (1989) Ecology of non-breeding social systems of Parus. Wilson Bull 101:263–288

    Google Scholar 

  • Estes JA et al (2011) Trophic downgrading of planet Earth. Science 333:301–306

    Article  CAS  PubMed  Google Scholar 

  • Galton F (1871) Gregariousness in cattle and men. MacMillan’s Mag 23:353–357

    Google Scholar 

  • Goodale E, Beauchamp G, Ruxton GD (2017) Mixed–species animal groups: behavior, community ecology and conservation. Academic Press, Oxford

    Google Scholar 

  • Goodale E et al (2020) Mixed company: a framework for understanding the composition and organization of mixed-species animal groups. Biol Rev 95:889–910

    Article  PubMed  Google Scholar 

  • Graves GR, Gotelli NJ (1993) Assembly of avian mixed species flocks in Amazonia. Proc Natl Acad Sci 90:1388–1391

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Harrap S, Quinn D (1995) Chickadees, tits, nuthatches and treecreepers. Princeton University Press, Princeton

    Google Scholar 

  • Hill JE, DeVault TL, Belant JL (2019) Cause-specific mortality of the world’s terrestrial vertebrates. Glob Ecol Biogeogr 28:680–689

    Article  Google Scholar 

  • Hillebrand H (2004) On the generality of the latitudinal diversity gradient. Am Nat 163:192–211

    Article  PubMed  Google Scholar 

  • Hogstad O (1978) Differentiation of foraging niche among tits, Parus spp., in Norway during winter. Ibis 120:139–146

    Article  Google Scholar 

  • Holt RD, Hochberg ME (2001) Indirect interactions, community modules and biological control: a theoretical perspective. CABI International, Wallingford

    Google Scholar 

  • Holt DW, Leroux LA (1996) Diets of Northern Pygmy-Owls and Northern Saw-Whet Owls in West-Central Montana. Wilson Bull 108:123–128

    Google Scholar 

  • Houston AI, McNamara JM, Hutchinson JMC (1993) General results concerning the trade-off between gaining energy and avoiding predation. Philos Trans R Soc Lond B Biol Sci 341:375–397

    Article  Google Scholar 

  • Ives AR, Dinnage R, Nell LA, Helmus M, Li D (2019) Model based phylogenetic analysis: R package version 1.0.2

  • Jarman PJ (1974) The social organization of antelope in relation to their ecology. Behaviour 48:216–267

    Article  Google Scholar 

  • Johansson US, Nylinder S, Ohlson JI, Tietze DT (2018) Reconstruction of the late Miocene biogeographical history of tits and chickadees (Aves: Passeriformes: Paridae): a comparison between discrete area analyses and probabilistic diffusion approach. J Biogeogr 45:14–25

    Article  Google Scholar 

  • Krams IA, Krama T, Freeberg TM, Krams R, Sieving KE (2020a) Attacks of songbirds in mixed-species flocks by Eurasian Sparrowhawks: strategies of predators and potential prey. J Field Ornithol 91:367–374

    Article  Google Scholar 

  • Krams IA et al (2020b) Egalitarian mixed-species bird groups enhance winter survival of subordinate group members but only in high-quality forests. Sci Rep 10:4005

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Kullberg C, Ekman J (2000) Does predation maintain tit community diversity? Oikos 89:41–45

    Article  Google Scholar 

  • Li Y, Li SH, Guo C, Zhang G, Zhou Y, Lu X (2015) Nest helpers improve parental survival but not offspring production in a high-elevation passerine, the Ground Tit, Pseudopodoces humilis. Ibis 157:567–574

    Article  Google Scholar 

  • MacDonald DW, Henderson DG (1977) Aspects of the behaviour and ecology of mixed species bird flocks in Kashmir. Ibis 119:489–493

    Google Scholar 

  • Maldonado-Coehlo M, Marini M (2004) Mixed-species bird flocks from Brazilian Atlantic forest: the effects of forest fragmentation and seasonality on their size, richness and stability. Biol Conserv 116:19–26

    Article  Google Scholar 

  • Matthysen E (1990) Non-breeding social organization in Parus. Curr Ornithol 7:209–249

    Google Scholar 

  • Møller AP, Laursen K (2019) The ecological significance of extremely large flocks of birds. Ecol Evol 9:6559–6567

    Article  PubMed  PubMed Central  Google Scholar 

  • Morse DH (1970) Ecological aspects of some mixed-species foraging flocks of birds. Ecol Monogr 40:119–168

    Article  Google Scholar 

  • Peters MK, Likare S, Kraemer M (2008) Effects of habitat fragmentation and degradation on flocks of African ant-following birds. Ecol Appl 18:847–858

    Article  PubMed  Google Scholar 

  • Reiczigel J, Lang Z, Rózsa L, Tothmeresz B (2008) Measures of sociality: two different views of group size. Anim Behav 75:715–721

    Article  Google Scholar 

  • Robb GN, McDonald RA, Chamberlain DE, Bearhop S (2008) Food for thought: supplementary feeding as a driver of ecological change in avian populations. Front Ecol Environ 6:476–484

    Article  Google Scholar 

  • Roslin T et al (2017) Higher predation risk for insect prey at low latitudes and elevations. Science 356:742–744

    Article  CAS  PubMed  Google Scholar 

  • Sainz-Borgo C, Koffler S, Jaffé K (2018) On the adaptive characteristics of bird flocks: small birds form mixed flocks. Ornitol Neotrop 29:289–296

    Article  Google Scholar 

  • Sandel AA, Miller JA, Mitani JC, Nunn CL, Patterson SK, Garamszegi LZ (2016) Assessing sources of error in comparative analyses of primate behavior: intraspecific variation in group size and the social brain hypothesis. J Hum Evol 94:126–133

    Article  PubMed  PubMed Central  Google Scholar 

  • Santini L et al (2018) Global drivers of population density in terrestrial vertebrates. Glob Ecol Biogeogr 27:968–979

    Article  Google Scholar 

  • Seppänen J-T, Forsman JT, Mönkkönnen M, Thomson RL (2007) Social information use is a process across time, space and ecology, reaching heterospecifics. Ecology 88:1622–1633

    Article  PubMed  Google Scholar 

  • Sinclair ARE, Mduma SAR, Brashares JS (2003) Patterns of predation in a diverse predator–prey system. Nature 425:288–290

    Article  CAS  PubMed  Google Scholar 

  • Sridhar H, Beauchamp G, Shanker K (2009) Why do birds participate in mixed-species foraging flocks? A large-scale synthesis. Anim Behav 78:337–347

    Article  Google Scholar 

  • Štorchová Z, Landová E, Frynta D (2010) Why some tits store food and others do not: evaluation of ecological factors. J Ethol 28:207–219

    Article  Google Scholar 

  • Suzuki TN (2012) Long-distance calling by the Willow Tit, Poecile montanus, facilitates formation of mixed-species foraging flocks. Ethology 118:10–16

    Article  Google Scholar 

  • Thiollay J-M, Jullien M (1998) Flocking behaviour of foraging birds in a neotropical rain forest and the antipredator defence hypothesis. Ibis 140:382–394

    Article  Google Scholar 

  • Thomson RL, Ferguson JWH (2007) Composition and foraging behaviour of mixed-species flocks in two adjacent African woodland habitats: a spatial and temporal perspective. Ostrich 78:65–73

    Article  Google Scholar 

  • Zhou L, Peabotuwage I, Luo K, Quan R-C, Goodale E (2021) Using playback to test leadership in mixed-species flocks and compare flocking with mobbing. Anim Behav 180:151–166

    Article  Google Scholar 

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Acknowledgements

We thank Sahas Barve for sharing information about predation risk in mixed-species flocks of tits in the Himalaya.

Funding

IK was supported by the Latvian Council of Science (Grants lzp-2021/1-0277, and lzp-2022/1-0348).

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Authors and Affiliations

  1. Montréal, Canada

    Guy Beauchamp

  2. Department of Biotechnology, Daugavpils University, Daugavpils, 5404, Latvia

    Indrikis Krams

  3. Department of Zoology and Animal Ecology, Faculty of Biology, University of Latvia, Riga, 1004, Latvia

    Indrikis Krams

  4. Institute of Ecology and Earth Sciences, University of Tartu, 50409, Tartu, Estonia

    Indrikis Krams

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  1. Guy Beauchamp
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  2. Indrikis Krams
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Contributions

GB and IK conceived the study and gathered the data, GB analyzed the data, and GB and IR wrote the manuscript.

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Communicated by Nina Farwig.

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Beauchamp, G., Krams, I. Flock size increases with the diversity and abundance of local predators in an avian family. Oecologia 202, 629–637 (2023). https://doi.org/10.1007/s00442-023-05425-7

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