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Goodale E, Magrath RD. Species diversity and interspecific information flow. Biol Rev Camb Philos Soc 2024; 99:999-1014. [PMID: 38279871 DOI: 10.1111/brv.13055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/14/2024] [Accepted: 01/15/2024] [Indexed: 01/29/2024]
Abstract
Interspecific information flow is known to affect individual fitness, population dynamics and community assembly, but there has been less study of how species diversity affects information flow and thereby ecosystem functioning and services. We address this question by first examining differences among species in the sensitivity, accuracy, transmissibility, detectability and value of the cues and signals they produce, and in how they receive, store and use information derived from heterospecifics. We then review how interspecific information flow occurs in communities, involving a diversity of species and sensory modes, and how this flow can affect ecosystem-level functions, such as decomposition, seed dispersal or algae removal on coral reefs. We highlight evidence that some keystone species are particularly critical as a source of information used by eavesdroppers, and so have a disproportionate effect on information flow. Such keystone species include community informants producing signals, particularly about predation risk, that influence other species' landscapes of fear, and aggregation initiators creating cues or signals about resources. We suggest that the presence of keystone species means that there will likely be a positive relationship in many communities between species diversity and information through a 'sampling effect', in which larger pools of species are more likely to include the keystone species by chance. We then consider whether the number and relative abundance of species, irrespective of the presence of keystone species, matter to interspecific information flow; on this issue, the theory is less developed, and the evidence scant and indirect. Higher diversity could increase the quantity or quality of information that is used by eavesdroppers because redundancy increases the reliability of information or because the species provide complementary information. Alternatively, there could be a lack of a relationship between species diversity and information if there is widespread information parasitism where users are not sources, or if information sourced from heterospecifics is of lower value than that gained personally or sourced from conspecifics. Recent research suggests that species diversity does have information-modulated community and ecosystem consequences, especially in birds, such as the diversity of species at feeders increasing resource exploitation, or the number of imitated species increasing responses to vocal mimics. A first step for future research includes comprehensive observations of information flow among different taxa and habitats. Then studies should investigate whether species diversity influences the cumulative quality or quantity of information at the community level, and consequently ecosystem-level processes. An applied objective is to conserve species in part for their value as sources of information for other species, including for humans.
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Affiliation(s)
- Eben Goodale
- Department of Health and Environmental Science, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Robert D Magrath
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
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2
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Bangal P, Sridhar H. Revisiting the 'nuclear species' concept: do we really know what we think we know? Philos Trans R Soc Lond B Biol Sci 2023; 378:20220108. [PMID: 37066658 PMCID: PMC10107234 DOI: 10.1098/rstb.2022.0108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/31/2023] [Indexed: 04/18/2023] Open
Abstract
The idea of 'nuclear species' has received a lot of attention in mixed-species flock research. Our impression of this literature is that referenced statements tend to cite the same papers in support of a small set of ideas, and often there is a mismatch between what papers contain and what they're cited for. Motivated by these impressions, we built and quantitatively examined a database of referenced statements about nuclearity in flocks. This confirmed our impression quantitatively, but more strikingly, a single paper stood out in its influence on ideas around nuclearity in flocks. Moynihan's 1962 monograph on mixed-species flocks in Panama, 'The organization and probable evolution of some mixed-species flocks of neotropical birds' published in Smithsonian Miscellaneous Collections, was cited twice as much as the next most-cited paper and was the most-cited paper for 10 out of 15 most-discussed ideas related to nuclearity. Further, a number of other highly cited papers are strongly influenced by Moynihan's ideas, i.e. its influence is much greater than what a count of citations conveys. We also found that Moynihan was mis-cited frequently. We juxtapose what we found from the citation analysis with what the paper actually contains to better understand the nature of support that Moynihan provides, and discuss the implications of our findings for what we know about and how we research nuclearity in flocks. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.
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Affiliation(s)
- Priti Bangal
- Nature Conservation Foundation, Mysore 570017, Karnataka, India
| | - Hari Sridhar
- Independent Researcher, Bengaluru 560003, Karnataka, India
- Konrad Lorenz Institute for Evolution and Cognition Research, A-3400 Klosterneuburg, Austria
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3
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Eavesdropping on conspecific alarm calls links birds across territory borders into a population-wide information network. Anim Behav 2022. [DOI: 10.1016/j.anbehav.2022.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Diniz P, Valls JF, Ramos DM. Foraging behaviour of an omnivorous bird varies in mixed-species groups. ETHOL ECOL EVOL 2022. [DOI: 10.1080/03949370.2022.2120082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Pedro Diniz
- Programa de Pós-Graduação em Ecologia, Universidade de Brasília, Brasília, DF 70910-900, Brazil
- Laboratório de Comportamento Animal, Departamento de Zoologia, Universidade de Brasília, Brasília, DF 70910-900, Brazil
| | - José F.M. Valls
- Embrapa Genetic Resources and Biotechnology, Brazilian Corporation of Agricultural Research/Embrapa, Brasilia, Brazil
| | - Desirée M. Ramos
- Embrapa Genetic Resources and Biotechnology, Brazilian Corporation of Agricultural Research/Embrapa, Brasilia, Brazil
- Departamento de Biodiversidade, Laboratório de Fenologia, Instituto de Biociências, Universidade Estadual Paulista UNESP, Rio Claro 13506-900, Brazil
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5
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Habitat use by mixed-species bird flocks in tropical forests of the Western Ghats, India. JOURNAL OF TROPICAL ECOLOGY 2022. [DOI: 10.1017/s026646742200030x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abstract
While mixed-species flocks of birds (hereafter ‘flocks’) have been widely studied, few studies have looked at the effect of habitat structure on flock presence and flocking propensity within a site. Here, we employ a use-availability approach in locations with flocks and random locations to ask whether habitat characteristics influence the presence of flocks, and whether structurally similar microhabitats support compositionally similar flocks. We also examine the effect of habitat on flock size and species richness, and the effect of intraspecifically gregarious flock participants on habitat selection. We find that flocks use a narrow subset of available tree density and canopy cover variation and prefer relatively less-dense areas with large trees and a complex foliage structure. Similar microhabitats do not result in compositionally similar flocks, and while foliage complexity was associated with flock size, no habitat characteristics influenced species richness. Flocks led by the intraspecifically gregarious western crowned warbler (Phylloscopus occipitalis), a potential nuclear species, showed preference for high foliage complexity and tree density. Thus, habitat preferences of intraspecifically gregarious species, which are followed by other species, could play a strong role in habitat selection in flocks. This suggests that degraded forests that cannot provide a suitable range of tree density, canopy cover, and/or complex vegetation structure may not support some core flock species around which flocks form, which may lead to decreased flocking in those patches.
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Liao C, Ding T, Chen C. The formation of “mega‐flocks” depends on vegetation structure in montane coniferous forests of Taiwan. Ecol Evol 2022; 12:e8608. [PMID: 35222969 PMCID: PMC8855335 DOI: 10.1002/ece3.8608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 01/12/2022] [Accepted: 01/17/2022] [Indexed: 11/05/2022] Open
Abstract
A mixed‐species bird flock is a social assemblage where two or more bird species are moving together while foraging and might benefit from increased foraging efficiency and antipredator vigilance. A “mega‐flock,” which includes flocking species from different vegetation strata, often exhibits high species diversity. Mechanisms for the formation of mega‐flocks have not yet been explored. In this study, we evaluated the influence of vegetation structure and bird species diversity in driving the occurrence of mega‐flocks. We investigated the composition of mixed‐species flocks, local bird communities, and vegetation structure in five vegetation types of two high‐elevation sites in central Taiwan. Mega‐flocks occurred more frequently in pine woodland than later successional stages of coniferous forests. However, species richness/diversity of local bird communities increased along successional stages. Therefore, vegetation variables exhibit more influence on the occurrence of mega‐flocks than local bird communities. Besides foliage height diversity, understory coverage also showed positive effects on flock size of mixed‐species flocks. Our results indicated that pine woodlands with more evenly distributed vegetation layers could facilitate the interactions of canopy and understory flocks and increase the formation of mega‐flocks and thus the complexity of mixed‐species flocks.
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Affiliation(s)
- Chun‐Chieh Liao
- School of Forestry and Resource Conservation National Taiwan University Taipei Taiwan
- Division of Ecology and Evolution Research School of Biology Australian National University Canberra Australian Capital Territory Australia
| | - Tzung‐Su Ding
- School of Forestry and Resource Conservation National Taiwan University Taipei Taiwan
- The Experimental Forest College of Bio‐resources and Agriculture National Taiwan University Nantou Taiwan
| | - Chao‐Chieh Chen
- Department of Biomedical Science and Environmental Biology Kaohsiung Medical University Kaohsiung Taiwan
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7
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Kaplan G. Casting the Net Widely for Change in Animal Welfare: The Plight of Birds in Zoos, Ex Situ Conservation, and Conservation Fieldwork. Animals (Basel) 2021; 12:ani12010031. [PMID: 35011137 PMCID: PMC8749551 DOI: 10.3390/ani12010031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/15/2021] [Accepted: 12/17/2021] [Indexed: 12/27/2022] Open
Abstract
Simple Summary Animal welfare measures have been designed to improve the health and environmental conditions of animals living under human control, for whatever reason. Welfare regulations have evolved also in line with new research insights into the cognitive, affective, and physiological domain of birds, as this paper discusses. This paper casts a critical eye on areas that Animal Welfare regulations have not reached at all, have not gone far enough, or are not regulated or supervised. It identifies the plight of birds living in captivity or being studied in the field, which either by neglect, ignorance, or design are subject to practices and procedures that may not meet basic welfare standards. The paper discusses some profound contradictions in the way we think about birds and their plight in today’s world: marked for extinction on one hand and highly admired as pets on the other; damaging fieldwork on one hand and the aims of conservation on the other. It highlights some common and distressing examples of poor welfare in birds. It also offers some solutions involving simple legislative changes and ways to eliminate some unacceptably low ethical standards in the handling and management of birds. Abstract This paper discusses paradoxes in our relationship to and treatment of birds in captive and conservation contexts. The paper identifies modern and new challenges that arise from declining bird numbers worldwide. Such challenges have partly changed zoos into providers of insurance populations specifically for species at risk of extinction. They have also accelerated fieldwork projects, but by using advanced technological tools and in increasing numbers, contradictorily, they may cause serious harm to the very birds studied for conservation purposes. In practice, very few avian species have any notable protection or guarantee of good treatment. The paper first deals with shortcomings of identifying problematic avian behavior in captive birds. It then brings together specific cases of field studies and captive breeding for conservation in which major welfare deficits are identified. Indeed, the paper argues that avian welfare is now an urgent task. This is not just because of declining bird numbers but because of investment in new technologies in field studies that may have introduced additional stressors and put at risk bird survival. While the paper documents a substantial number of peer-reviewed papers criticizing practices counter to modern welfare standards, they have by and large not led to changes in some practices. Some solutions are suggested that could be readily implemented and, to my knowledge, have never been considered under a welfare model before.
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Affiliation(s)
- Gisela Kaplan
- School of Science and Technology, University of New England, Armidale, NSW 2351, Australia
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8
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Zhou L, Peabotuwage I, Luo K, Quan RC, Goodale E. Using playback to test leadership in mixed-species flocks and compare flocking with mobbing. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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9
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Affiliation(s)
- Jakub Szymkowiak
- Population Ecology Research Unit, Faculty of Biology, Adam Mickiewicz Univ. Poznań Poland
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10
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Jones HH, Robinson SK. Vegetation structure drives mixed-species flock interaction strength and nuclear species roles. Behav Ecol 2020. [DOI: 10.1093/beheco/araa103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Mixed-species flocks are a key facilitative interaction for tropical birds. Forest fragmentation leads to species loss and spatial turnover in these flocks, yet it is unknown how these changes to composition influence within-flock species interactions. We used network analysis to characterize flocking interactions along a fragment-size gradient in the Colombian Western Andes. We asked 1) how patch size, edge density, and vegetation structure explained network measures indicative of flock cohesion, 2) whether changes were driven by flocking species turnover or changes to the frequency of species co-occurrence, and 3) whether nuclear species, those that maintain flock stability and cohesion, changed in importance across the gradient. We constructed weighted social networks from flock compositions observed on 500-m transects, and then calculated global network measures and the centrality of six nuclear species. Patch size and edge density did not correlate with interspecific co-occurrence patterns, but interaction strength increased with canopy height. Flocks contained numerous, weak interactions, and there were no flock subtypes, suggesting flock composition was dynamic and unstructured. Several redundant nuclear species were present and varied in importance based on ecological conditions. A chlorospingus (Passerellidae) was most central in old-growth forest, whereas several tanager (Thraupidae) species became more central in smaller fragments and disturbed forest. When partitioning network dissimilarity, we found that 66% of dissimilarity resulted from species turnover, whereas only 34% resulted from changes to species co-occurrence. This finding suggests that coherence of flocking behavior itself is maintained even as extensive species turnover occurs from continuous forest to small fragments.
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Affiliation(s)
- Harrison H Jones
- Department of Biology, University of Florida, Gainesville, FL, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
| | - Scott K Robinson
- Department of Biology, University of Florida, Gainesville, FL, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
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11
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Zhang Q, Holyoak M, Goodale E, Liu Z, Shen Y, Liu J, Zhang M, Dong A, Zou F. Trait-environment relationships differ between mixed-species flocking and nonflocking bird assemblages. Ecology 2020; 101:e03124. [PMID: 32564355 DOI: 10.1002/ecy.3124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 04/06/2020] [Accepted: 05/05/2020] [Indexed: 12/27/2022]
Abstract
Hypotheses about the mechanisms of community assembly suggest that biotic and abiotic filters constrain species establishment through selection on their functional traits. It is unclear how differences in traits influence the niche dimensions of closely related bird species when they coexist in spatiotemporally heterogeneous environments. Further, it is necessary to take into account their participation in mixed-species flocks, social systems that can include both competition and facilitation. For 6 yr, we conducted counts of forest bird species and took measurements of environmental variables along an elevational gradient in the Nanling Mountains, China. To disentangle different deterministic and historical/stochastic processes between flocking and nonflocking bird assemblages, we first compared phylogenetic and functional structure, and community-weighted mean trait values (CWM). We further assessed elevational variations in trait-environment relationships. We found that the flocking and nonflocking bird assemblages were structured by environmental gradients in contrasting ways. The nonflocking assemblage showed a strong change from over-dispersed to clustered community structure with increasing elevations, consistent with the strong selective pressures of a harsh environment (i.e., environmental filtering). The nonflocking assemblage also displayed significant trait-environment relationships in bivariate correlations and multivariate ordination space, including specific morphological and foraging traits that are linked to vegetation characteristics (e.g., short trees at high elevations). By contrast, flocking birds were more resilient to habitat change with elevation, with relatively consistent community membership, and showed fewer trait-environment associations. CWM of traits that are known to be associated with species' propensity to join mixed-species flocks, including small body size and broad habitat specificity, were linked to the flocking assemblage consistently across the elevational gradient. Collectively, our trait-based analyses provide strong evidence that trait-environment relationships differ between flocking and nonflocking bird assemblages. Besides serving as bellwethers of changing environments, emergent properties of flock systems may increase the resilience of animal communities undergoing environmental change. Mixed-species flocks present an ideal model with which to explore cooccurrence of closely related species, because habitat filtering may be buffered, and the patterns observed are therefore the outcomes of species interactions including both competition and facilitation.
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Affiliation(s)
- Qiang Zhang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Science, Guangzhou, 510260, China
| | - Marcel Holyoak
- Department of Environmental Science and Policy, University of California, Davis, California, 95616, USA
| | - Eben Goodale
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, 530004, China
| | - Zhifa Liu
- Nanling National Nature Reserve, Shaoguan, 512727, China
| | - Yong Shen
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Science, Guangzhou, 510260, China
| | - Jiajia Liu
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
| | - Min Zhang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Science, Guangzhou, 510260, China
| | - Anqiang Dong
- College of Life Sciences, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China
| | - Fasheng Zou
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Science, Guangzhou, 510260, China
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12
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Lowney AM, Flower TP, Thomson RL. Kalahari skinks eavesdrop on sociable weavers to manage predation by pygmy falcons and expand their realized niche. Behav Ecol 2020. [DOI: 10.1093/beheco/araa057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Eavesdropping on community members has immediate and clear benefits. However, little is known regarding its importance for the organization of cross-taxa community structure. Furthermore, the possibility that eavesdropping could allow species to coexist with a predator and access risky foraging habitat, thereby expanding their realized niche, has been little considered. Kalahari tree skinks (Trachylepis spilogaster) associate with sociable weaver (Philetairus socius) colonies as do African pygmy falcons (Polihierax semitorquatus), a predator of skinks and weavers. We undertook observational and experimental tests to determine if skinks eavesdrop on sociable weavers to mitigate any increase in predation threat that associating with weaver colonies may bring. Observations reveal that skinks use information from weavers to determine when predators are nearby; skinks were more active, more likely to forage in riskier habitats, and initiated flight from predators earlier in the presence of weavers compared with when weavers were absent. Playback of weaver alarm calls caused skinks to increase vigilance and flee, confirming that skinks eavesdrop on weavers. Furthermore, skinks at sociable weaver colonies were more likely to flee than skinks at noncolony trees, suggesting that learning is mechanistically important for eavesdropping behavior. Overall, it appears that eavesdropping allows skinks at colony trees to gain an early warning signal of potential predators, expand their realized niche, and join communities, whose predators may otherwise exclude them.
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Affiliation(s)
- Anthony M Lowney
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - Tom P Flower
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
- Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
- Department of Biology, Capilano University, North Vancouver, BC, Canada
| | - Robert L Thomson
- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
- Section of Ecology, Department of Biology, University of Turku, Turun yliopisto, Vesilinnantie , Turku, Finland
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13
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Jiang D, Sieving KE, Meaux E, Goodale E. Seasonal changes in mixed-species bird flocks and antipredator information. Ecol Evol 2020; 10:5368-5382. [PMID: 32607159 PMCID: PMC7319245 DOI: 10.1002/ece3.6280] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 03/28/2020] [Accepted: 03/28/2020] [Indexed: 11/18/2022] Open
Abstract
Animals acquire information produced by other species to reduce uncertainty and avoid predators. Mixed-species flocks (MSFs) of birds are ubiquitous in forest ecosystems and structured, in part, around interspecific information transfer, with "nuclear" species providing information that other species eavesdrop on. We hypothesized that in a seasonal tropical forest, the amount of information produced by birds about predation would be dynamic and particularly would decrease inside MSFs when the nuclear species leave MSFs to breed. We obtained baseline information on MSF encounter rate and species composition along established sampling routes over 9 months near the Sino-Vietnamese border. We also conducted three experiments to quantify information produced by different species in response to typical predator encounters, including a moving predator stimulus presented inside of MSFs, and a stationary predator model presented both inside and outside of MSFs. MSFs were much less frequent in the breeding season with fewer individuals of the nuclear species, David's Fulvetta (Alcippe davidi), participating, though the diversity of other species remained stable. Fulvettas were the dominant producer of alarm-related information both to the moving and stationary stimuli in MSFs and were also among the most active mobbers to stimuli presented outside of MSFs. In the breeding season, they tended to call less to the moving stimulus, and substantially fewer individuals responded to the in-flock stationary stimulus. Other species increased their own information production at stationary predator stimuli (inside and outside of MSFs) during the breeding season, perhaps due to their increased investment in offspring during this time. Yet even during the breeding season, David's Fulvetta remained the highest producer of information about predators in MSFs. Hence, while we show that information production in MSFs can be somewhat dynamic, we describe a continually asymmetric communication system, in which a nuclear species is important to the whole community.
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Affiliation(s)
- Demeng Jiang
- Guangxi Key Laboratory of Forest Ecology and ConservationCollege of ForestryGuangxi UniversityNanningChina
| | - Kathryn E. Sieving
- Department of Wildlife Ecology & ConservationUniversity of FloridaGainesvilleFLUSA
| | - Estelle Meaux
- Guangxi Key Laboratory of Forest Ecology and ConservationCollege of ForestryGuangxi UniversityNanningChina
| | - Eben Goodale
- Guangxi Key Laboratory of Forest Ecology and ConservationCollege of ForestryGuangxi UniversityNanningChina
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14
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Stears K, Schmitt MH, Wilmers CC, Shrader AM. Mixed-species herding levels the landscape of fear. Proc Biol Sci 2020; 287:20192555. [PMID: 32126952 DOI: 10.1098/rspb.2019.2555] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Prey anti-predator behaviours are influenced by perceived predation risk in a landscape and social information gleaned from herd mates regarding predation risk. It is well documented that high-quality social information about risk can come from heterospecific herd mates. Here, we integrate social information with the landscape of fear to quantify how these landscapes are modified by mixed-species herding. To do this, we investigated zebra vigilance in single- and mixed-species herds across different levels of predation risk (lion versus no lion), and assessed how they manage herd size and the competition-information trade-off associated with grouping behaviour. Overall, zebra performed higher vigilance in high-risk areas. However, mixed-species herding reduced vigilance levels. We estimate that zebra in single-species herds would have to feed for approximately 35 min more per day in low-risk areas and approximately 51 min more in high-risk areas to compensate for the cost of higher vigilance. Furthermore, zebra benefitted from the competition-information trade-off by increasing the number of heterospecifics while keeping the number of zebra in a herd constant. Ultimately, we show that mixed-species herding reduces the effects of predation risk, whereby zebra in mixed-species herds, under high predation risk, perform similar levels of vigilance compared with zebra in low-risk scenarios.
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Affiliation(s)
- Keenan Stears
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106, USA.,School of Life Sciences, University of KwaZulu-Natal, Scottsville 3209, South Africa.,South African Environmental Observation Network, Ndlovu Node, Phalaborwa 1390, South Africa
| | - Melissa H Schmitt
- School of Life Sciences, University of KwaZulu-Natal, Scottsville 3209, South Africa.,South African Environmental Observation Network, Ndlovu Node, Phalaborwa 1390, South Africa.,Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95064, USA
| | - Christopher C Wilmers
- Department of Environmental Studies, University of California, Santa Cruz, CA 95064, USA
| | - Adrian M Shrader
- School of Life Sciences, University of KwaZulu-Natal, Scottsville 3209, South Africa.,Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0028, South Africa
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15
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Goodale E, Sridhar H, Sieving KE, Bangal P, Colorado Z GJ, Farine DR, Heymann EW, Jones HH, Krams I, Martínez AE, Montaño-Centellas F, Muñoz J, Srinivasan U, Theo A, Shanker K. Mixed company: a framework for understanding the composition and organization of mixed-species animal groups. Biol Rev Camb Philos Soc 2020; 95:889-910. [PMID: 32097520 PMCID: PMC7383667 DOI: 10.1111/brv.12591] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 02/02/2020] [Accepted: 02/06/2020] [Indexed: 12/19/2022]
Abstract
Mixed-species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two-dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single-species groups wherein all individuals obtain the same supplementary, group-size-related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader-follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities.
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Affiliation(s)
- Eben Goodale
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530004, China
| | - Hari Sridhar
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, 560012, India.,National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, Karnataka, 560012, India
| | - Kathryn E Sieving
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, U.S.A
| | - Priti Bangal
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Gabriel J Colorado Z
- Departamento de Ciencias Forestales, Universidad Nacional de Colombia, Medellín, 050034, Colombia
| | - Damien R Farine
- Department of Collective Behavior, Max Planck Institute of Animal Behavior, Universitätsstrasse 10, D-78464, Konstanz, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, D-78464, Konstanz, Germany.,Department of Biology, University of Konstanz, D-78464, Konstanz, Germany
| | - Eckhard W Heymann
- Deutsches Primatenzentrum, Leibniz-Institut für Primatenforschung, D-37077, Göttingen, Germany
| | - Harrison H Jones
- Department of Biology, University of Florida, Gainesville, FL, 32611, U.S.A.,Florida Museum of Natural History, Gainesville, FL, 32611, U.S.A
| | - Indrikis Krams
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, 51410, Estonia.,Department of Zoology and Animal Ecology, Faculty of Biology, University of Latvia, Rīga, 1004, Latvia
| | - Ari E Martínez
- Department of Biological Sciences, California State University, Long Beach, CA, 90840, U.S.A
| | - Flavia Montaño-Centellas
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, 32611, U.S.A.,Instituto de Ecologia, Universidad Mayor de San Andres, La Paz, 10077, Bolivia
| | - Jenny Muñoz
- Zoology Department and Biodiversity Research Center, University of British Columbia, Vancouver, BC, V6T 1ZA, Canada
| | - Umesh Srinivasan
- Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ, 08540, U.S.A
| | - Anne Theo
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Kartik Shanker
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, 560012, India.,Dakshin Foundation, Bengaluru, 560092, India
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16
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Meise K, Franks DW, Bro-Jørgensen J. Alarm communication networks as a driver of community structure in African savannah herbivores. Ecol Lett 2019; 23:293-304. [PMID: 31775182 PMCID: PMC6973068 DOI: 10.1111/ele.13432] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/12/2019] [Accepted: 08/29/2019] [Indexed: 01/15/2023]
Abstract
Social information networks have the potential to shape the spatial structure of ecological communities by promoting the formation of mixed‐species groups. However, what actually drives social affinity between species in the wild will depend on the characteristics of the species available to group. Here we first present an agent‐based model that predicts trait‐related survival benefits from mixed‐species group formation in a multi‐species community and we then test the model predictions in a community‐wide field study of African savannah herbivores using multi‐layered network analysis. We reveal benefits from information transfer about predators as a key determinant of mixed‐species group formation, and that dilution benefits alone are not enough to explain patterns in interspecific sociality. The findings highlight the limitations of classical ecological approaches focusing only on direct trophic interactions when analysing community structure and suggest that declines in species occupying central social network positions, such as key informants, can have significant repercussions throughout communities.
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Affiliation(s)
- Kristine Meise
- Mammalian Behaviour and Evolution Group, Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, University of Liverpool, Neston, CH64 7TE, UK.,Department of Biology, University of York, York, YO10 5DD, UK
| | - Daniel W Franks
- Department of Biology, University of York, York, YO10 5DD, UK.,Department of Computer Science, University of York, York, YO10 5GH, UK
| | - Jakob Bro-Jørgensen
- Mammalian Behaviour and Evolution Group, Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, University of Liverpool, Neston, CH64 7TE, UK
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17
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Jones HH, Sieving KE. Foraging ecology drives social information reliance in an avian eavesdropping community. Ecol Evol 2019; 9:11584-11597. [PMID: 31695870 PMCID: PMC6822049 DOI: 10.1002/ece3.5561] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/14/2019] [Accepted: 07/26/2019] [Indexed: 11/06/2022] Open
Abstract
Vertebrates obtain social information about predation risk by eavesdropping on the alarm calls of sympatric species. In the Holarctic, birds in the family Paridae function as sentinel species; however, factors shaping eavesdroppers' reliance on their alarm calls are unknown. We compared three hypothesized drivers of eavesdropper reliance: (a) foraging ecology, (b) degree of sociality, and (c) call relevance (caller-to-eavesdropper body-size difference). In a rigorous causal-comparative design, we presented Tufted Titmouse (Baeolophus bicolor) alarm calls to 242 individuals of 31 ecologically diverse bird species in Florida forests and recorded presence/absence and type (diving for cover or freezing in place) of response. Playback response was near universal, as individuals responded to 87% of presentations (N = 211). As an exception to this trend, the sit-and-wait flycatcher Eastern Phoebe (Sayornis phoebe) represented 48% of the nonresponses. We tested 12 predictor variables representing measures relevant to the three hypothesized drivers, distance to playback speaker, and vulnerability at time of playback (eavesdropper's microhabitat when alarm call is detected). Using model-averaged generalized linear models, we determined that foraging ecology best predicted playback response, with aerial foragers responding less often. Foraging ecology (distance from trunk) and microhabitat occupied during playback (distance to escape cover) best predicted escape behavior type. We encountered a sparsity of sit-and-wait flycatchers (3 spp.), yet their contrasting responses relative to other foraging behaviors clearly identified foraging ecology as a driver of species-specific antipredator escape behavior. Our findings align well with known links between the exceptional visual acuity and other phenotypic traits of flycatchers that allow them to rely more heavily on personal rather than social information while foraging. Our results suggest that foraging ecology drives species-specific antipredator behavior based on the availability and type of escape cover.
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Affiliation(s)
- Harrison H. Jones
- Department of Wildlife Ecology and ConservationUniversity of FloridaGainesvilleFLUSA
- Department of BiologyUniversity of FloridaGainesvilleFLUSA
| | - Kathryn E. Sieving
- Department of Wildlife Ecology and ConservationUniversity of FloridaGainesvilleFLUSA
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18
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McQueen A, Kempenaers B, Dale J, Valcu M, Emery ZT, Dey CJ, Peters A, Delhey K. Evolutionary drivers of seasonal plumage colours: colour change by moult correlates with sexual selection, predation risk and seasonality across passerines. Ecol Lett 2019; 22:1838-1849. [PMID: 31441210 DOI: 10.1111/ele.13375] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022]
Abstract
Some birds undergo seasonal colour change by moulting twice each year, typically alternating between a cryptic, non-breeding plumage and a conspicuous, breeding plumage ('seasonal plumage colours'). We test for potential drivers of the evolution of seasonal plumage colours in all passerines (N = 5901 species, c. 60% of all birds). Seasonal plumage colours are uncommon, having appeared on multiple occasions but more frequently lost during evolution. The trait is more common in small, ground-foraging species with polygynous mating systems, no paternal care and strong sexual dichromatism, suggesting it evolved under strong sexual selection and high predation risk. Seasonal plumage colours are also more common in species predicted to have seasonal breeding schedules, such as migratory birds and those living in seasonal climates. We propose that seasonal plumage colours have evolved to resolve a trade-off between the effects of natural and sexual selection on colouration, especially in seasonal environments.
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Affiliation(s)
- Alexandra McQueen
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Bart Kempenaers
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard Gwinner Str, 82319, Seewiesen, Germany
| | - James Dale
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, 0745, New Zealand
| | - Mihai Valcu
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard Gwinner Str, 82319, Seewiesen, Germany
| | - Zachary T Emery
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Cody J Dey
- Great Lakes Institute for Environmental Research, University of Windsor, 401 Sunset Avenue, Windsor, ON, Canada
| | - Anne Peters
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Kaspar Delhey
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
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19
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Camerlenghi E, Tellaroli P, Griggio M, Martínez AE. Information about Predators Varies across an Amazonian Rain Forest as a Result of Sentinel Species Distribution. Am Nat 2019; 194:E134-E139. [PMID: 31613671 DOI: 10.1086/705242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Information about predation risk is of fundamental value in biological communities. Because many prey species have shared predators, eavesdropping on other species' alarms is a widely recognized mechanism underlying the formation of mixed-species groups. However, information transfer may vary both across and within groups because some species provide higher-quality information about predators than others. We tested this phenomenon in Amazonian understory mixed-species flocks of birds in which two sentinel species-the bluish-slate antshrike (Thamnomanes schistogynus) and the dusky-throated antshrike (Thamnomanes ardesiacus)-occupy different habitats and provide alarm calls that are used by eavesdropping flock mates. In a playback experiment, two associate species responded significantly more strongly to alarm calls from the same sentinel species, reflecting the greater reliability of information about predator threats that could affect survival and habitat choice. Our work provides evidence of a repeated asymmetry across space in the available information about threats.
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20
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Meise K, Franks DW, Bro-Jørgensen J. Using social network analysis of mixed-species groups in African savannah herbivores to assess how community structure responds to environmental change. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190009. [PMID: 31352889 PMCID: PMC6710573 DOI: 10.1098/rstb.2019.0009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The dynamics of wildlife populations often depend heavily on interspecific interactions and understanding the underlying principles can be an important step in designing conservation strategies. Behavioural ecological studies can here provide useful insights into the structure and function of communities and their likely response to environmental changes. In this study of the Masai Mara herbivore community, we use a social network approach to investigate social affinities between species and how these change over the year in response to seasonal changes in ecological conditions. We find that even though social networks were correlated across different ecological conditions, for half the species dyads in the community, the strength of social affinities responded to changes in rainfall and/or the presence of migratory wildebeest. Several species consequentially adopted more or less central positions in the network depending on the ecological conditions. The findings point out interspecific social links that are likely to be attenuated or strengthened as a consequence of human-induced environmental changes and therefore call for particular attention from conservation managers. The eco-evolutionary ramifications of the perturbations of social affinities still require further study. This article is part of the theme issue ‘Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation’.
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Affiliation(s)
- Kristine Meise
- Mammalian Behaviour and Evolution Group, Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, University of Liverpool, Neston CH64 7TE, UK.,Department of Biology, University of York, York YO10 5DD, UK
| | - Daniel W Franks
- Department of Biology, University of York, York YO10 5DD, UK.,Department of Computer Science, University of York, York YO10 5GH, UK
| | - Jakob Bro-Jørgensen
- Mammalian Behaviour and Evolution Group, Department of Evolution, Ecology and Behaviour, Institute of Integrative Biology, University of Liverpool, Neston CH64 7TE, UK
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21
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Linley GD, Guay PJ, Weston MA. Are disturbance separation distances derived from single species applicable to mixed-species shorebird flocks? WILDLIFE RESEARCH 2019. [DOI: 10.1071/wr18198] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Abstract
ContextHuman disturbance threatens many bird species worldwide. Flight-initiation distances (FIDs) offer a scientific basis for separation distances between fauna and agents of disturbance, such as people. However, most available FIDs are from single-species groups. Multi-species flocks have received scant attention with regard to their FIDs; yet, they are extremely common in nature.
AimTo examine suitable separation distances for mixed-species shorebird flocks by comparing single-species FIDs with those of the same species in mixed-species flocks.
MethodWe examined FIDs in mixed- and single-species flocks of four shorebirds (double-banded plover, Charadrius bicinctus, red-capped plover, Charadrius ruficapillus, red-necked stint, Calidris ruficollis, and curlew sandpiper, Calidris ferruginea). FIDs were collected in comparable habitat and sites with similar (i.e. highly restricted) regimes of human occurrence.
ResultsFIDs of single-species flocks of these species differed in their FID to an approaching walker. Different species permutations in mixed-species flocks resulted in different FIDs. FIDs of mixed-species flocks were lower than or the same as the FIDs of single-species groups of constituent species.
Conclusions and implicationsIn our study system, separation distances (e.g. buffers; zones that exclude humans to reduce shorebird disturbance) based on FIDs of single species also would be efficacious for mixed-species flocks containing those species.
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