scholarly journals Shyer and larger bird species show more reduced fear of humans when living in urban environments

2018 ◽  
Vol 14 (4) ◽  
pp. 20170730 ◽  
Author(s):  
Javier delBarco-Trillo
Keyword(s):  
Bird Species ◽  
Generalized Least Squares ◽  
Urban Environments ◽  
Phenotypic Traits ◽  
Flight Initiation Distance ◽  
Natural Habitats ◽  
Urban Populations ◽  
Rural And Urban ◽  
Consistent Response ◽  
Flight Initiation

As the natural habitats of many species are degraded or disappear, there is scope for these species to be established in urban habitats. To ease the establishment and maintenance of urban populations of more species we need to better understand what degree of phenotypical change to expect as different species transition into urban environments. During the first stages of urban colonization, behavioural changes such as an increase in boldness are particularly important. A consistent response in urban populations is to decrease the distance at which individuals flee from an approaching human (flight initiation distance, or FID). Performing a phylogenetic generalized least-squares (PGLS) analysis on 130 avian species, I found that the largest changes in FID between rural and urban populations occur in species that are larger-bodied and naturally shy (higher rural FID), two phenotypic traits that are not normally associated with urban colonizers. More unlikely species may thus be able to colonize urban environments, especially if we design cities in ways that promote such urban colonizations.

scholarly journals The effects of habituation on boldness of urban and rural song sparrows (Melospiza melodia)

Behaviour ◽  
2021 ◽  
pp. 1-15
Author(s):  
Taylor Elaine Fossett ◽  
Jeremy Hyman
Keyword(s):  
Repeated Exposure ◽  
Melospiza Melodia ◽  
Song Sparrow ◽  
Rural Populations ◽  
Flight Initiation Distance ◽  
Urban Birds ◽  
Wildlife Species ◽  
Song Sparrows ◽  
Rural And Urban ◽  
Flight Initiation

Abstract As urbanization increases globally, wildlife species are changing their behaviour in many ways. Urban animals are often bolder, or less fearful of new stimuli, than rural animals. While adaptation can drive behavioural changes in urban animals, other factors, such as learning or habituation, can also lead to behavioural modifications. To determine how repeated exposure to a non-threatening human affects song sparrow (Melospiza melodia) behaviour in urban and rural habitat, we measured boldness as flight initiation distance (FID), for 5 consecutive days. We found that urban birds had consistently lower FID’s than their rural counterparts from days 1–4, yet there was no difference in rural and urban FID by trial 5. FID decreased over 5 days of repeated trials in the rural populations, but not the urban. These results suggest that habituation can occur quickly in rural birds and may account for the greater boldness we typically see in urban populations.

scholarly journals Effect of human recreation on bird anti-predatory response

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5093 ◽  
Author(s):  
Yves Bötsch ◽  
Selina Gugelmann ◽  
Zulima Tablado ◽  
Lukas Jenni
Keyword(s):  
Spatial Distribution ◽  
Flight Initiation Distance ◽  
Urban Birds ◽  
Natural Habitats ◽  
Human Presence ◽  
Escape Responses ◽  
Human Use ◽  
Predatory Response ◽  
Human Recreation ◽  
Flight Initiation

Wildlife perceive humans as predators, and therefore normally flushes. Flight initiation distance (FID) is the distance a human can approach an animal at a steady pace until it flushes. Recently, several studies showed differences in within-species FID according to human presence by comparing urban and rural habitats, with urban birds showing reduced FIDs. However, urban and rural habitats also differ in structure, which might affect FID. Therefore, in order to understand the real effect of human presence, we investigated whether differences in FID are also present in natural habitats (forests), differing only in the intensity of human use for recreation. We found that human frequentation had a distinct effect on bird escape responses, with shorter FIDs in forests more-heavily frequented by humans than in forests rarely visited by humans. Whether this finding is driven by non-random spatial distribution of personalities (shy vs. bold) or phenotypic plasticity (habituation to humans) cannot be assessed with our data. Studies relying on FIDs should also incorporate human recreation intensity, as this affects the measurements strongly.

Differences in flight initiation distance (FID) between rural and urban populations of two species of Australian birds

Behaviour ◽  
2019 ◽  
Vol 156 (11) ◽  
pp. 1151-1164
Author(s):  
Sara Davey ◽  
Melanie Massaro ◽  
Rafael Freire
Keyword(s):  
Rural Populations ◽  
Flight Initiation Distance ◽  
Urban Birds ◽  
Urban Centre ◽  
New Town ◽  
Rural And Urban ◽  
Australian Birds ◽  
The City ◽  
Predator Behaviour ◽  
Flight Initiation

Abstract Although flight initiation distance (FID) has been shown to be shorter in urban compared to rural populations of birds, less is known about how the characteristics of the urban environment, such as the population size and age of the city influences the FID and other aspects of anti-predator behaviour. Urban willie wagtails and magpie larks in a relatively small and new town had shorter FID than rural conspecifics. Both species were more likely to show a short, rather than long, escape flight if the experimenter started walking towards the bird from further away. There was some indication that urban birds may be more likely to show a short escape flight than rural birds. We conclude that anti-predator responses of birds can be influenced by a relatively small, recently established and sparsely-populated town. Additionally, the possibility of the characteristics of the urban centre influencing variation in the FID response is discussed.

scholarly journals On fearfulness and patterns of bird urbanisation in an Australian metropolis

2015 ◽  
Author(s):  
Lawrence E Conole
Keyword(s):  
Explanatory Power ◽  
Bird Species ◽  
Predictive Ability ◽  
Landscape Scale ◽  
Bird Flight ◽  
Rural And Urban ◽  
Behavioural Factors ◽  
Urban Exploiter ◽  
Acting In Concert ◽  
Flight Initiation

I have utilised an assemblage of 91 bird species, their urban tolerance status objectively classified, with data on bird flight initiation distance (FID), to test questions of the importance of birds’ fearfulness of humans in determining urban tolerance or intolerance in the metropolis of Melbourne, Australia. While several studies have shown that mean FID for bird species (mFID) differs between rural and urban populations of bird species, stronger predictive ability is shown by variability in FID (cvFID) in modelling urban invasiveness. I test two hypotheses. Firstly, that mFID will be shorter in urban exploiter bird species than urban adapters and avoiders. Secondly that cvFID is positively correlated with bird incidence at the landscape scale in Melbourne. Relatively weak explanatory power of cvFID found in this study suggest that environmental and behavioural factors acting in concert better explain the urban tolerance of bird species and assemblages, rather than fearfulness alone.

When and how do predator starting distances affect flight initiation distances?

2005 ◽  
Vol 83 (8) ◽  
pp. 1045-1050 ◽  
Author(s):  
W E Cooper, Jr.
Keyword(s):  
Bird Species ◽  
Ecological Factors ◽  
Flight Initiation Distance ◽  
Lizard Species ◽  
Urosaurus Ornatus ◽  
Approach Speed ◽  
Monitoring Costs ◽  
Sceloporus Virgatus ◽  
The Relationship ◽  
Flight Initiation

The distance separating predator and prey when the predator begins to approach, starting distance, was recently shown to affect flight initiation distance in many bird species, raising questions about the effect's generality, variation with ecological factors, and economic basis. I studied the effect in two lizard species that forage by ambush and escape into nearby refuges. Monitoring costs during approach are absent because ambushers remain immobile while scanning for prey and predators. Risks are minimized because of the proximity to refuge. Flight initiation distance increased weakly with starting distance in Sceloporus virgatus Smith, 1938 significantly only at rapid approach speed. It was not significant in Urosaurus ornatus (Baird and Girard, 1852) at slow approach speed. Flight initiation distance is predicted to increase with starting distance, owing to monitoring costs and assessment by prey of greater risk during prolonged approaches. The significant effect in S. virgatus, which lacks monitoring costs, is the first indication that risk affects the relationship between starting distance and flight initiation distance. Conditions in which starting distance is important and its possible effects in earlier studies are discussed, as well as standardizing approaches and possible artifactual effects of starting distance.

scholarly journals Do squirrels in human disturbed areas become habituated to humans? A measure of flight initiation distance across disturbance gradients

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Megan D Bjordal
Keyword(s):  
North American ◽  
Human Disturbance ◽  
Tamiasciurus Hudsonicus ◽  
Flight Initiation Distance ◽  
Natural Habitats ◽  
Red Squirrels ◽  
Disturbed Areas ◽  
Significant Difference ◽  
North American Red Squirrels ◽  
Flight Initiation

Human population growth results in destruction of natural habitats, although some animals are adapting to living in areas with human disturbance. North American red squirrels (Tamiasciurus hudsonicus) may be one such species that is successfully adapting to living alongside humans. Flight initiation distance, the distance at which an animal flees from an approaching predator, may act as an indicator of habituation to humans. I predicted that if North American red squirrels were habituating to humans, their flight initiation distance would decrease along a gradient of increasing human disturbance. To examine this, I measured flight initiation distances of 39 North American red squirrels across eight sites, classified as low, medium or high human disturbance areas. No significant difference was found in mean flight initiation distances between disturbance levels, indicating that squirrel flight initiation distance may not be sensitive to small scales of human disturbance gradients.

Cognition and Adaptation to Urban Environments

2020 ◽  
pp. 253-267
Author(s):  
Daniel Sol ◽  
Oriol Lapiedra ◽  
Simon Ducatez
Keyword(s):  
Adaptive Evolution ◽  
Cognitive Processes ◽  
Urban Areas ◽  
Urban Environments ◽  
Heritable Variation ◽  
Natural Habitats ◽  
Urban Populations ◽  
Population Extinction ◽  
Generation Times ◽  
Evolutionary Consequences

Urbanization is one of the most drastic alterations of natural habitats, causing sudden adaptive mismatches that make population persistence difficult for many organisms. Urban contexts may be challenging for adaptation, particularly for animals with long generation times with slow evolutionary responses. This chapter argues that cognition may play a major role in facilitating evolutionary adaptation of animals to the urban environment. By regulating how animals gather, preserve, and use information, cognition can influence adaptive evolution in urban areas by (1) allowing individuals to choose the habitats and resources that better match their phenotypes, and (2) helping animals to construct learned responses to challenges they have never or rarely experienced before. These cognitive processes can weaken the strength of selection. However, they can also facilitate adaptive evolution by reducing the risk of population extinction and by ensuring that individuals are more gradually exposed to the new conditions. In addition, cognitive processes can maintain genetic diversity for selection to act upon in the future as well as promoting local adaptation by reducing gene flow with nearby non-urban populations. Finally, learned behaviours can allow the population to move close to the realm of attraction of new adaptive peaks, driving evolution toward novel directions. Cognition itself may also evolve in urban areas—particularly in long-lived generalists—if it exhibits enough heritable variation. Echoing recent suggestions in cognitive ecology, the chapter highlights the need to design and carry out experiments explicitly designed to assess the evolutionary consequences of cognition in urban populations.

scholarly journals On fearfulness and patterns of bird urbanisation in an Australian metropolis

2015 ◽  
Author(s):  
Lawrence E Conole
Keyword(s):  
Explanatory Power ◽  
Bird Species ◽  
Predictive Ability ◽  
Landscape Scale ◽  
Bird Flight ◽  
Rural And Urban ◽  
Behavioural Factors ◽  
Urban Exploiter ◽  
Acting In Concert ◽  
Flight Initiation

I have utilised an assemblage of 91 bird species, their urban tolerance status objectively classified, with data on bird flight initiation distance (FID), to test questions of the importance of birds’ fearfulness of humans in determining urban tolerance or intolerance in the metropolis of Melbourne, Australia. While several studies have shown that mean FID for bird species (mFID) differs between rural and urban populations of bird species, stronger predictive ability is shown by variability in FID (cvFID) in modelling urban invasiveness. I test two hypotheses. Firstly, that mFID will be shorter in urban exploiter bird species than urban adapters and avoiders. Secondly that cvFID is positively correlated with bird incidence at the landscape scale in Melbourne. Relatively weak explanatory power of cvFID found in this study suggest that environmental and behavioural factors acting in concert better explain the urban tolerance of bird species and assemblages, rather than fearfulness alone.

scholarly journals Gut Microbiota Dynamics in Natural Populations of Pintomyia evansi under Experimental Infection with Leishmania infantum

2021 ◽  
Vol 9 (6) ◽  
pp. 1214
Author(s):  
Rafael José Vivero ◽  
Victor Alfonso Castañeda-Monsalve ◽  
Luis Roberto Romero ◽  
Gregory D. Hurst ◽  
Gloria Cadavid-Restrepo ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Leishmania Infantum ◽  
Natural Populations ◽  
Illumina Miseq ◽  
Urban Environments ◽  
High Load ◽  
Leishmania Infection ◽  
Experimental Conditions ◽  
Rural And Urban ◽  
Negative Effect

Pintomyia evansi is recognized by its vectorial competence in the transmission of parasites that cause fatal visceral leishmaniasis in rural and urban environments of the Caribbean coast of Colombia. The effect on and the variation of the gut microbiota in female P. evansi infected with Leishmania infantum were evaluated under experimental conditions using 16S rRNA Illumina MiSeq sequencing. In the coinfection assay with L. infantum, 96.8% of the midgut microbial population was composed mainly of Proteobacteria (71.0%), followed by Cyanobacteria (20.4%), Actinobacteria (2.7%), and Firmicutes (2.7%). In insect controls (uninfected with L. infantum) that were treated or not with antibiotics, Ralstonia was reported to have high relative abundance (55.1–64.8%), in contrast to guts with a high load of infection from L. infantum (23.4–35.9%). ASVs that moderately increased in guts infected with Leishmania were Bacillus and Aeromonas. Kruskal–Wallis nonparametric variance statistical inference showed statistically significant intergroup differences in the guts of P. evansi infected and uninfected with L. infantum (p < 0.05), suggesting that some individuals of the microbiota could induce or restrict Leishmania infection. This assay also showed a negative effect of the antibiotic treatment and L. infantum infection on the gut microbiota diversity. Endosymbionts, such as Microsporidia infections (<2%), were more often associated with guts without Leishmania infection, whereas Arsenophonus was only found in guts with a high load of Leishmania infection and treated with antibiotics. Finally, this is the first report that showed the potential role of intestinal microbiota in natural populations of P. evansi in susceptibility to L. infantum infection.

Bird community structure in natural and urbanized habitats along an altitudinal gradient in Pauri district (Garhwal Himalaya) of Uttarakhand state, India

Biologia ◽  
2012 ◽  
Vol 67 (4) ◽  
Author(s):  
Archana Naithani ◽  
Dinesh Bhatt
Keyword(s):  
Community Structure ◽  
Altitudinal Gradient ◽  
Diversity Index ◽  
Bird Species ◽  
Bird Community ◽  
High Elevation ◽  
Base Line ◽  
Natural Habitats ◽  
Forest Habitat ◽  
Rarefaction Analysis

AbstractIn the Indian subcontinent there is hardly any study that compares the bird community structure of urban/suburban areas with those of forest habitat. The present survey identified diverse assemblages of birds in the Pauri district at different elevations. A total of 125 bird species belonging to 40 families including two least count species (Lophura leucomelanos and Pucrasia marcolopha) were recorded during this survey in the forest and urbanized habitats of Pauri District (Garhwal Hiamalaya) of Uttarakhand state, India. The high elevation (Pauri 1600–2100 m a.s.l.), mid elevation (Srikot-Khanda 900–1300 m a.s.l.) and low elevation (Srinagar 500–900 m a.s.l.) contributed 88.8%, 63.2% and 58.4% of the total species respectively. Rarefaction analysis and Shannon diversity index showed that the high elevation forest habitat had highest bird species richness (BSR) and bird species diversity (BSD) followed by the mid and then the low elevation forests. BSR and BSD fluctuated across seasons at all elevations but not across habitat types. Present study provides a base line data about avian community composition in urbanized and natural habitats along altitudinal gradient in the study area. This information may be useful to the conservation biologists for the better management and conservation of the avifauna in the Western Himalaya, a part of one of the hot biodiversity spots of the world.

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