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Adams CB, Papeş M, Price CA, Freeberg TM. Influence of social and physical environmental variation on antipredator behavior in mixed-species parid flocks. PLoS One 2023; 18:e0295910. [PMID: 38128009 PMCID: PMC10735029 DOI: 10.1371/journal.pone.0295910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/30/2023] [Indexed: 12/23/2023] Open
Abstract
Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor) regularly form flocks with multiple species through the winter months, including white-breasted nuthatches (Sitta carolinensis). Earlier studies found that behavior of both chickadees and titmice was sensitive to mixed-species flock composition. Little is known about the influence of background noise level and vegetation density on the antipredator behaviors of individuals within these flocks, however. We tested for the effects of vegetation density, traffic noise, and flock composition (conspecific number, flock diversity, and flock size) on antipredator behavioral responses following an alarm call playback (Study 1) and an owl model presentation (Study 2) at feeders. We recorded background traffic noise and performed lidar scans to quantify vegetation density at each site. After a feeder had been stocked with seed and a flock was present, we recorded calls produced, and we identified flock composition metrics. We coded seed-taking latency, call latency, mob latency, and mob duration following the respective stimulus presentation and tested for effects of flock composition metrics, vegetation density, and background noise on these responses. For the alarm call playback study, flock composition drove behaviors in chickadees and titmice, and vegetation density drove behaviors in chickadees and nuthatches. For the owl model study, conspecific number predicted behavior in chickadees, and mob duration was predicted by nuthatch number. The results reveal individual sensitivity to group composition in anti-predatory and foraging behavior in simulated risky contexts. Additionally, our data suggest that the modality of perceived simulated risk (acoustic vs. visual) and the density of vegetation influence behavior in these groups.
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Affiliation(s)
- Colton B. Adams
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, United States of America
- Department of Psychology, University of Tennessee, Knoxville, TN, United States of America
| | - Monica Papeş
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, United States of America
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN, United States of America
| | - Charles A. Price
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN, United States of America
| | - Todd M. Freeberg
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, United States of America
- Department of Psychology, University of Tennessee, Knoxville, TN, United States of America
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2
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Bełcik M, Lenda ML, Pustkowiak S, Woźniak B, Skórka P. Social information modifies the associations between forest fragmentation and the abundance of a passerine bird. Sci Rep 2023; 13:21386. [PMID: 38049553 PMCID: PMC10696010 DOI: 10.1038/s41598-023-48512-8] [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: 01/30/2023] [Accepted: 11/27/2023] [Indexed: 12/06/2023] Open
Abstract
Habitat loss and fragmentation are the main factors driving the occurrence and abundance of species in the landscape. However, the local occurrence and abundance of species may also depend on conspecific and heterospecific social information e.g. clues of animals' presence or their voices. We investigated the impact of the interaction between different types of social information and forest fragmentation on the abundance of the song thrush, Turdus philomelos, in Central Europe. Three types of social information (attractive, repulsive, and mixed) and procedural control were broadcasted via loudspeakers in 150 forest patches that varied in size and isolation metrics. Repulsive social information (cues of presence of predator) decreased abundance of song thrush. Also, the repulsive social information changed the association between forest patch isolation, size and the abundance. Attractive social information (songs of the studied thrush) had no effect on song thrush abundance. However, the attractive social information reversed the positive correlation between habitat patch size and the abundance. Mixed social information (both repulsive and attractive) had no impact on the abundance nor interacted with habitat fragmentation. The observed effects mostly did not last to the next breeding season. Overall, our findings indicate that lands of fear and social attraction could modify the effect of habitat fragmentation on the species abundance but these effects probably are not long-lasting.
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Affiliation(s)
- Michał Bełcik
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120, Kraków, Poland.
- Centre for Biodiversity and Conservation Science, University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Magdalena Lidia Lenda
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120, Kraków, Poland
| | - Sylwia Pustkowiak
- Population Ecology Lab, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Bartłomiej Woźniak
- Department of Forest Zoology and Wildlife Management, Institute of Forest Sciences, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776, Warsaw, Poland
| | - Piotr Skórka
- Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120, Kraków, Poland
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3
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Martínez AE, Si X, Zhou L, Zeng D, Ding P, Goodale E. Interspecific sociality alters the colonization and extinction rates of birds on subtropical reservoir islands. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220096. [PMID: 37066642 PMCID: PMC10107236 DOI: 10.1098/rstb.2022.0096] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 11/25/2022] [Indexed: 04/18/2023] Open
Abstract
Island biogeography theory has proved a robust approach to predicting island biodiversity on the assumption of species equivalency. However, species differ in their grouping behaviour and are entangled by complex interactions in island communities, such as competition and mutualism. We here investigated whether intra- and/or interspecific sociality may influence biogeographic patterns, by affecting movement between islands or persistence on them. We classified bird species in a subtropical reservoir island system into subcommunities based on their propensity to join monospecific and mixed-species flocks. We found that subcommunities which had high propensity to flock interspecifically had higher colonization rates and lower extinction rates over a 10-year period. Intraspecific sociality increased colonization in the same analysis. A phylogenetically corrected analysis confirmed the importance of interspecific sociality, but not intraspecific sociality. Group-living could enable higher risk crossings, with greater vigilance also linked to higher foraging efficiency, enabling colonization or long-term persistence on islands. Further, if group members are other species, competition can be minimized. Future studies should investigate different kinds of island systems, considering positive species interactions driven by social behaviour as potential drivers of community assembly on islands. 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)
- Ari E. Martínez
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, 100 DaXue Road, Nanning, Guangxi 530004, People's Republic of China
| | - Xingfeng Si
- Zhejiang Zhoushan Archipelago Observation and Research Station, Institute of Eco-Chongming, Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, People's Republic of China
| | - Liping Zhou
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, 100 DaXue Road, Nanning, Guangxi 530004, People's Republic of China
- Kunming Natural History Museum of Zoology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, People's Republic of China
| | - Di Zeng
- Zhejiang Zhoushan Archipelago Observation and Research Station, Institute of Eco-Chongming, Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, People's Republic of China
| | - Ping Ding
- MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Eben Goodale
- Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, 100 DaXue Road, Nanning, Guangxi 530004, People's Republic of China
- Department of Health and Environmental Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, People's Republic of China
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4
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Farina A, James P. The Landscape of Fear as a Safety Eco-Field: Experimental Evidence. BIOSEMIOTICS 2023; 16:61-84. [PMID: 37101821 PMCID: PMC9979121 DOI: 10.1007/s12304-023-09522-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/03/2023] [Indexed: 06/19/2023]
Abstract
UNLABELLED In a development of the ecosemiotic vivo-scape concept, a 'safety eco-field' is proposed as a model of a species response to the safety of its environment. The safety eco-field is based on the ecosemiotic approach which considers environmental safety as a resource sought and chosen by individuals to counter predatory pressure. To test the relative safety of different locations within a landscape, 66 bird feeders (BF) were deployed in a regular 15 × 15 m grid in a rural area, surrounded by shrubs, small trees, hedgerows, and buildings. On each of 48 days in November 2021 and February and March 2022, dried mealworms were placed on each BF and counts of larvae at each BF were made at noon and dusk. The European robin (Erithacus rubecula) and the great tit (Parus major) were the most regular visitors to the BFs. Land cover at each BF was recorded. Bird behaviour at the BFs was noted from direct video recordings of the birds at nine selected BFs, totalling 32 daily sessions in March. The different behaviours of the European robin and the great tit were observable. The safety eco-field changed according to the month and the time of day. The distance of the BF from the woodland edges seemed to be important only in the morning. In the afternoon, BFs that were more distant from the woodland edges received the highest number of visits. Weather conditions were found to influence the number of mealworms removed, but this requires further investigation. A significant relationship between land cover and the number of mealworm larvae removed from the BFs was observed. Within the grid of BF, three regions were distinguishable which were related to land cover in the safety eco-field process. The experimental framework confirms the adequacy, at least for birds that have cryptic predators, to map the landscape as a proxy of safety resource. From the video recordings it was noted that the European robin visits were distributed throughout the day without apparent temporal preferences, while the great tit visits were concentrated in the central part of the day. This result has the limitation of the short period of observation (March) and should be extended to the entire period of the experiment to eventually capture seasonal variation. The experimental evidence obtained confirms that the ecosemiotic-based models of safety eco-field are an efficient approach to explain bird feeding preferences and behaviours. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s12304-023-09522-1.
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Affiliation(s)
- Almo Farina
- Department of Pure and Applied Sciences, Urbino University, Urbino, Italy
| | - Philip James
- School of Science, Engineering and Environment, University of Salford, Salford, UK
- School of Education, Environment and Development, University of Manchester, Manchester, UK
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5
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Radvan M, Rendall AR, Weston MA. The habitat connectivity hypothesis of escape in urban woodland birds. Behav Ecol 2023; 34:297-305. [PMID: 36998995 PMCID: PMC10047614 DOI: 10.1093/beheco/arac127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 11/29/2022] [Accepted: 12/20/2022] [Indexed: 02/12/2023] Open
Abstract
Abstract
Habitat destruction and fragmentation increasingly bring humans into close proximity with wildlife, particularly in urban contexts. Animals respond to humans using nuanced anti-predator responses, especially escape, with responses influenced by behavioral and life history traits, the nature of the risk, and aspects of the surrounding environment. Although many studies examine associations between broad-scale habitat characteristics (i.e., habitat type) and escape response, few investigate the influence of fine-scale aspects of the local habitat within which escape occurs. We test the “habitat connectivity hypothesis,” suggesting that given the higher cost of escape within less connected habitats (due to the lack of protective cover), woodland birds should delay escape (tolerate more risk) than when in more connected habitat. We analyze flight-initiation distances (FIDs) of five species of woodland birds in urban Melbourne, south-eastern Australia. A negative effect of habitat connectivity (the proportion of the escape route with shrubs/trees/perchable infrastructure) on distance fled was evident for all study species, suggesting a higher cost of escape associated with lower connectivity. FID did not vary with connectivity at the location at which escape was initiated (four species), apart from a positive effect of habitat connectivity on FID for Noisy Miner Manorina melanocephala. We provide some support for two predictions of the “habitat connectivity hypothesis” in at least some taxa, and conclude it warrants further investigation across a broader range of taxa inhabiting contrasting landscapes. Increasing habitat connectivity within urban landscapes may reduce escape stress experienced by urban birds.
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Affiliation(s)
- Max Radvan
- Deakin University Geelong, Australia, Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science, Engineering and the Built Environment , Burwood Campus, VIC , Australia
| | - Anthony R Rendall
- Deakin University Geelong, Australia, Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science, Engineering and the Built Environment , Burwood Campus, VIC , Australia
| | - Michael A Weston
- Deakin University Geelong, Australia, Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science, Engineering and the Built Environment , Burwood Campus, VIC , Australia
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6
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White JH, Moscicki DJ, Jobes D, Hardin JB, Chamberlain MJ, Collier BA. Breeding season survival of female Rio Grande wild turkeys in south‐central Texas. WILDLIFE SOC B 2022. [DOI: 10.1002/wsb.1286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jacob H. White
- School of Renewable Natural Resources Louisiana State University Baton Rouge 70803 LA USA
| | - David J. Moscicki
- School of Renewable Natural Resources Louisiana State University Baton Rouge 70803 LA USA
| | - Doug Jobes
- Texas Parks and Wildlife Department Austin 78744 TX USA
| | | | - Michael J. Chamberlain
- Warnell School of Forestry and Natural Resources University of Georgia Athens 30602 GA USA
| | - Bret A. Collier
- School of Renewable Natural Resources Louisiana State University Baton Rouge 70803 LA USA
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7
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Yu F, Li G, Wei S, Yi X, Ma J, Ma K, Chen G. Rodent-mediated plant seed dispersal: What happens to the seeds after entering the gaps with different sizes? Ecol Evol 2022; 12:e8286. [PMID: 35136541 PMCID: PMC8809425 DOI: 10.1002/ece3.8286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 11/23/2022] Open
Abstract
In general, it is accepted that gap formation significantly affects the placement of scatter-hoarded seeds by small rodents, but the effects of different forest gap sizes on the seed-eating and scatter-hoarding behaviors of small rodents remain unclear. Thus, we examined the effects of a closed-canopy forest, forest edge, and gaps with different sizes on the spatial dispersal of Quercus variabilis acorns and cache placement by small rodents using coded plastic tags in the Taihang Mountains, China. The seeds were removed rapidly, and there were significant differences in the seed-eating and caching strategies between the stand types. We found that Q. variabilis acorns were usually eaten after being removed from the closed-canopy forest and forest edges. By contrast, the Q. variabilis acorns in the forest gap stands were more likely to be scatter-hoarded. The dispersal distances of Q. variabilis acorns were significantly longer in the forest gap plots compared with the closed canopy and forest edge plots. However, the proportion of scatter-hoarded seeds did not increase significantly as the gap size increased. In small-scale oak reforestation projects or research, creating small gaps to promote rodent-mediated seed dispersal may effectively accelerate forest recovery and successional processes.
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Affiliation(s)
- Fei Yu
- College of Life SciencesHenan Normal UniversityXinxiangChina
- State Key Laboratory of Urban and Regional EcologyResearch Center for Eco‐Environmental SciencesChinese Academy of SciencesBeijingChina
| | - Guangjie Li
- College of Life SciencesHenan Normal UniversityXinxiangChina
| | - Shanshan Wei
- College of Life SciencesHenan Normal UniversityXinxiangChina
| | - Xianfeng Yi
- College of Life SciencesQufu Normal UniversityQufuChina
| | - Jianmin Ma
- College of Life SciencesHenan Normal UniversityXinxiangChina
| | - Keming Ma
- State Key Laboratory of Urban and Regional EcologyResearch Center for Eco‐Environmental SciencesChinese Academy of SciencesBeijingChina
| | - Guangwen Chen
- College of Life SciencesHenan Normal UniversityXinxiangChina
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8
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Rainforest bird communities threatened by extreme fire. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2021.e01985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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9
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Harris J, Smith L, McMurry S. Fine-scale plasticity in nest placement can compensate for poor quality junipers as nesting trees for gray vireos. PeerJ 2021; 9:e12477. [PMID: 34820199 PMCID: PMC8588862 DOI: 10.7717/peerj.12477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 10/20/2021] [Indexed: 11/29/2022] Open
Abstract
Understanding the interactions between behavior and habitat characteristics can have important implications for species of conservation concern. Gray vireos (Vireo vicinior) are one example of a species of conservation concern that is understudied in terms of nest survival probabilities and the habitat characteristics that influence them. Our objective was to determine if habitat features such as juniper density, juniper foliage density, or tree height influence nest survival probabilities, and if gray vireo nest placement can mitigate habitat risks. Based on previous work, we expected daily nest survival probabilities to be associated with nest height and surrounding vegetation. We monitored 89 nests in central New Mexico from 2016–2018 to estimate daily nest survival probabilities. We compared variation in nest placement, nest tree characteristics, and surrounding vegetation between failed and successful nests using logistic exposure models and Akaike Information Criteria. Daily and cumulative nest survival probability were 0.983 (95% CI [0.973–0.989]) and 0.575 (95% CI [0.444–0.702]), respectively. Top models predicting nest survival included a negative interaction between nest-tree foliage density and the distance of the nest from the edge of the nesting tree. This suggests that gray vireos can mitigate risks associated with low nest concealment by nesting closer to the interior of the nesting tree.
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Affiliation(s)
- Jonathan Harris
- Integrative Biology, Oklahoma State University, Stillwater, Oklahoma, United States
| | - Loren Smith
- Integrative Biology, Oklahoma State University, Stillwater, Oklahoma, United States
| | - Scott McMurry
- Integrative Biology, Oklahoma State University, Stillwater, Oklahoma, United States
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10
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Lee JS, Callaghan CT, Cornwell WK. Using citizen science to measure recolonisation of birds after the Australian 2019–2020 mega‐fires. AUSTRAL ECOL 2021. [DOI: 10.1111/aec.13105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Joshua S. Lee
- Centre for Ecosystem Science School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney New South Wales 2052 Australia
| | - Corey T. Callaghan
- Centre for Ecosystem Science School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney New South Wales 2052 Australia
- Ecology & Evolution Research Centre School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney New South Wales Australia
| | - William K. Cornwell
- Centre for Ecosystem Science School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney New South Wales 2052 Australia
- Ecology & Evolution Research Centre School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney New South Wales Australia
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11
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Tucker JM, Moriarty KM, Ellis MM, Golding JD. Effective sampling area is a major driver of power to detect long‐term trends in multispecies occupancy monitoring. Ecosphere 2021. [DOI: 10.1002/ecs2.3519] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Jody M. Tucker
- USDA Forest Service, Pacific Southwest Region 1323 Club Drive Vallejo California94592USA
| | - Katie M. Moriarty
- USDA Forest Service, Pacific Northwest Research Station 3625 93rd Avenue Olympia Washington98512USA
| | - Martha M. Ellis
- Department of Mathematics Montana State University 1156‐1174 South 11th Street Bozeman Montana59715USA
| | - Jessie D. Golding
- USDA Forest Service, Rocky Mountain Research Station 800 East Beckwith Avenue Missoula Montana59801USA
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12
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Kolkert HL, Smith R, Rader R, Reid N. Prey removal in cotton crops next to woodland reveals periodic diurnal and nocturnal invertebrate predation gradients from the crop edge by birds and bats. Sci Rep 2021; 11:5256. [PMID: 33664383 PMCID: PMC7970855 DOI: 10.1038/s41598-021-84633-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 02/16/2021] [Indexed: 11/29/2022] Open
Abstract
Factors influencing the efficacy of insectivorous vertebrates in providing natural pest control services inside crops at increasing distances from the crop edge are poorly understood. We investigated the identity of vertebrate predators (birds and bats) and removal of sentinel prey (mealworms and beetles) from experimental feeding trays in cotton crops using prey removal trials, camera traps and observations. More prey was removed during the day than at night, but prey removal was variable at the crop edge and dependent on the month (reflecting crop growth and cover) and time of day. Overall, the predation of mealworms and beetles was 1-times and 13-times greater during the day than night, respectively, with predation on mealworms 3-5 times greater during the day than night at the crop edge compared to 95 m inside the crop. Camera traps identified many insectivorous birds and bats over crops near the feeding trays, but there was no evidence of bats or small passerines removing experimental prey. A predation gradient from the crop edge was evident, but only in some months. This corresponded to the foraging preferences of open-space generalist predators (magpies) in low crop cover versus the shrubby habitat preferred by small passerines, likely facilitating foraging away from the crop edge later in the season. Our results are in line with Optimal Foraging Theory and suggest that predators trade-off foraging behaviour with predation risk at different distances from the crop edge and levels of crop cover. Understanding the optimal farm configuration to support insectivorous bird and bat populations can assist farmers to make informed decisions regarding in-crop natural pest control and maximise the predation services provided by farm biodiversity.
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Affiliation(s)
- Heidi L Kolkert
- Ecosystem Management, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
| | - Rhiannon Smith
- Ecosystem Management, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Romina Rader
- Ecosystem Management, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Nick Reid
- Ecosystem Management, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
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13
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Ausprey IJ, Newell FL, Robinson SK. Adaptations to light predict the foraging niche and disassembly of avian communities in tropical countrysides. Ecology 2020; 102:e03213. [PMID: 33002207 DOI: 10.1002/ecy.3213] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 06/21/2020] [Accepted: 08/06/2020] [Indexed: 12/22/2022]
Abstract
The role of light in partitioning ecological niche space remains a frontier in understanding the assembly of terrestrial vertebrate communities and their response to global change. Leveraging recent advances in biologging technology and intensive field surveys of cloud forest bird communities across an agricultural land use gradient in the Peruvian Andes, we demonstrate that eye size predicts (1) the ambient light microenvironment used by free-ranging birds, (2) their foraging niche, and (3) species-specific sensitivity to agricultural land use change. For 15 species carrying light sensors (N = 71 individuals), light intensity levels were best explained by eye size and foraging behavior, with larger-eyed species using darker microenvironments. Across the cloud forest bird community (N = 240 species), hyperopic ("far-sighted") foragers, (e.g., flycatchers), had larger eyes compared to myopic ("near-sighted") species (e.g., gleaners and frugivores); eye size was also larger for myopic insectivores that foraged in the forest understory. Eye size strongly predicted sensitivity to brightly lit habitats across an agricultural land use gradient. Species that increased in abundance in mixed intensity agriculture, including fencerows, silvopasture, and pasture, had smaller eyes, suggesting that light acts as an environmental filter when communities disassemble in a human-disturbed landscape. We suggest that eye size represents a novel functional trait contributing to terrestrial vertebrate community assembly and sensitivity to habitat disturbance.
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Affiliation(s)
- Ian J Ausprey
- Florida Museum of Natural History and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
| | - Felicity L Newell
- Florida Museum of Natural History and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
| | - Scott K Robinson
- Florida Museum of Natural History and Department of Biology, University of Florida, Gainesville, Florida, 32611, USA
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14
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Monitoring Urban Green Infrastructure Changes and Impact on Habitat Connectivity Using High-Resolution Satellite Data. REMOTE SENSING 2020. [DOI: 10.3390/rs12183072] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In recent decades, the City of Stockholm, Sweden, has grown substantially and is now the largest city in Scandinavia. Recent urban growth is placing pressure on green areas within and around the city. In order to protect biodiversity and ecosystem services, green infrastructure is part of Stockholm municipal planning. This research quantifies land-cover change in the City of Stockholm between 2003 and 2018 and examines what impact urban growth has had on its green infrastructure. Two 2018 WorldView-2 images and three 2003 QuickBird-2 images were used to produce classifications of 11 land-cover types using object-based image analysis and a support vector machine algorithm with spectral, geometric and texture features. The classification accuracies reached over 90% and the results were used in calculations and comparisons to determine the impact of urban growth in Stockholm between 2003 and 2018, including the generation of land-cover change statistics in relation to administrative boundaries and green infrastructure. For components of the green infrastructure, i.e., habitat networks for selected sensitive species, habitat network analysis for the European crested tit (Lophophanes cristatus) and common toad (Bufo bufo) was performed. Between 2003 and 2018, urban areas increased by approximately 4% while green areas decreased by 2% in comparison with their 2003 areal amounts. The most significant urban growth occurred through expansion of the transport network, paved surfaces and construction areas which increased by 12%, mainly at the expense of grassland and coniferous forest. Examination of urban growth within the green infrastructure indicated that most land area was lost in dispersal zones (28 ha) while the highest percent change was within habitat for species of conservation concern (14%). The habitat network analysis revealed that overall connectivity decreased slightly through patch fragmentation and areal loss mainly caused by road expansion on the outskirts of the city. The habitat network analysis also revealed which habitat areas are well-connected and which are most vulnerable. These results can assist policymakers and planners in their efforts to ensure sustainable urban development including sustaining biodiversity in the City of Stockholm.
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15
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Fardell LL, Pavey CR, Dickman CR. Fear and stressing in predator-prey ecology: considering the twin stressors of predators and people on mammals. PeerJ 2020; 8:e9104. [PMID: 32391213 PMCID: PMC7196326 DOI: 10.7717/peerj.9104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 04/09/2020] [Indexed: 12/28/2022] Open
Abstract
Predators induce stress in prey and can have beneficial effects in ecosystems, but can also have negative effects on biodiversity if they are overabundant or have been introduced. The growth of human populations is, at the same time, causing degradation of natural habitats and increasing interaction rates of humans with wildlife, such that conservation management routinely considers the effects of human disturbance as tantamount to or surpassing those of predators. The need to simultaneously manage both of these threats is particularly acute in urban areas that are, increasingly, being recognized as global hotspots of wildlife activity. Pressures from altered predator-prey interactions and human activity may each initiate fear responses in prey species above those that are triggered by natural stressors in ecosystems. If fear responses are experienced by prey at elevated levels, on top of responses to multiple environmental stressors, chronic stress impacts may occur. Despite common knowledge of the negative effects of stress, however, it is rare that stress management is considered in conservation, except in intensive ex situ situations such as in captive breeding facilities or zoos. We propose that mitigation of stress impacts on wildlife is crucial for preserving biodiversity, especially as the value of habitats within urban areas increases. As such, we highlight the need for future studies to consider fear and stress in predator-prey ecology to preserve both biodiversity and ecosystem functioning, especially in areas where human disturbance occurs. We suggest, in particular, that non-invasive in situ investigations of endocrinology and ethology be partnered in conservation planning with surveys of habitat resources to incorporate and reduce the effects of fear and stress on wildlife.
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Affiliation(s)
- Loren L. Fardell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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16
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Birds’ gap-crossing in open matrices depends on landscape structure, tree size, and predation risk. Perspect Ecol Conserv 2020. [DOI: 10.1016/j.pecon.2020.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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17
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Medina I, Langmore NE. Host density predicts the probability of parasitism by avian brood parasites. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180204. [PMID: 30967082 DOI: 10.1098/rstb.2018.0204] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The spatial distribution of hosts can be a determining factor in the reproductive success of parasites. Highly aggregated hosts may offer more opportunities for reproduction but can have better defences than isolated hosts. Here we connect macro- and micro-evolutionary processes to understand the link between host density and parasitism, using avian brood parasites as a model system. We analyse data across more than 200 host species using phylogenetic comparative analyses and quantify parasitism rate and host reproductive success in relation to spatial distribution using field data collected on one host species over 6 years. Our comparative analysis reveals that hosts occurring at intermediate densities are more likely to be parasitized than colonial or widely dispersed hosts. Correspondingly, our intraspecific field data show that individuals living at moderate densities experience higher parasitism rates than individuals at either low or high densities. Moreover, we show for the first time that the effect of host density on host reproductive success varies according to the intensity of parasitism; hosts have greater reproductive success when living at high densities if parasitism rates are high, but fare better at low densities when parasitism rates are low. We provide the first evidence of the trade-off between host density and parasitism at both macro- and micro-evolutionary scales in brood parasites. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.
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Affiliation(s)
- Iliana Medina
- 1 Division of Ecology and Evolution, Australian National University , Australian Capital Territory, 0200 , Australia.,2 School of BioSciences, The University of Melbourne , Parkville, Victoria, 3052 , Australia
| | - Naomi E Langmore
- 1 Division of Ecology and Evolution, Australian National University , Australian Capital Territory, 0200 , Australia
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18
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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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19
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Additive effects of connectivity provided by different habitat types drive plant assembly. Sci Rep 2019; 9:13952. [PMID: 31562348 PMCID: PMC6764998 DOI: 10.1038/s41598-019-50184-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/17/2019] [Indexed: 11/30/2022] Open
Abstract
How connectivity affects plant assemblages is a central issue in landscape ecology. So far, empirical studies have produced contradictory results, possibly because studies: (1) inaccurately assess connectivity by prioritizing the respective effect of the type of habitat on plant assemblages and (2) omit the range of possible plant responses to connectivity depending on dispersal vectors. We focused on three dominant habitat types in agricultural landscapes (woodland, grassland and cropland), and analysed the effect of connectivity on herbaceous plant assemblage similarity for three primary dispersal modes (animal-dispersed, wind-dispersed and unassisted). Using circuit theory, we measured connectivity provided by woodland, grassland and cropland habitats independently. The similarity of plant assemblages was evaluated relative to the random expectation based on the regional pool. Overall, plant assemblage similarity in woodlands and temporary grasslands was dependent on connectivity, but not in wheat croplands. Only animal-dispersed species responded to connectivity. The similarity of animal-dispersed assemblages in woodlands was increased by the connectivity provided by woodland habitats, but was reduced by cropland habitats, whereas in temporary grasslands, similarity was increased by the connectivity provided by cropland habitats. Our results suggest that animal-dispersed species supplement their dispersal pathways, thus improving our knowledge of plant assembly rules in fragmented landscapes.
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Bailey JM, Reudink MW, Otter KA. Supplemental feeding may reduce responsiveness of Black-capped Chickadees ( Poecile atricapillus) to avian mobbing calls during gap-crossing experiments. CAN J ZOOL 2019. [DOI: 10.1139/cjz-2018-0161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Deforestation creates gaps in forest habitat, which can limit the movements of many avian species. Increased predation risk associated with crossing open habitats is often considered the primary impediment to crossing gaps. However, other factors such as energetic reserves may also influence these decisions. We conducted playback experiments before and after supplemental feeding of Black-capped Chickadees (Poecile atricapillus (Linnaeus, 1766)) to investigate how energetic reserves influenced gap-crossing decisions. Black-capped Chickadees were less likely to respond to playbacks, whether conducted within forests or across gaps, after supplemental feeding. This suggests that energetic reserves may have less influence on gap-crossing decisions than on the willingness of birds to respond to mobbing calls in general. We recommend that future studies investigating gap-crossing decisions using playbacks account for differences in resource availability among sampling locations, especially when making comparisons across discrete habitats.
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Affiliation(s)
- Jacob M. Bailey
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9, Canada
| | - Matthew W. Reudink
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Ken A. Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9, Canada
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Barros FM, Martello F, Peres CA, Pizo MA, Ribeiro MC. Matrix type and landscape attributes modulate avian taxonomic and functional spillover across habitat boundaries in the Brazilian Atlantic Forest. OIKOS 2019. [DOI: 10.1111/oik.05910] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Fabio M. Barros
- Dept of Ecology, São Paulo State Univ. (UNESP) Rio Claro Brazil
| | - Felipe Martello
- Dept of Environmental Sciences, São Carlos Federal Univ. (UFSCAR) São Carlos Brazil
| | - Carlos A. Peres
- School of Environmental Sciences, Univ. of East Anglia (UEA) Norwich UK
| | - Marco A. Pizo
- Dept of Zoology, São Paulo State Univ. (UNESP) Rio Claro Brazil
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Martínez AE, Parra E, Collado LF, Vredenburg VT. Deconstructing the landscape of fear in stable multi-species societies. Ecology 2018. [PMID: 28632944 DOI: 10.1002/ecy.1935] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Animal distributions are influenced by variation in predation risk in space, which has been described as the "landscape of fear." Many studies suggest animals also reduce predation risk by eavesdropping on heterospecific alarm calls, allowing them to occupy otherwise risky habitats. One unexplored area of study is understanding how different species' alarms vary in quality, and how this variation is distributed in the landscape. We tested this phenomenon in a unique system of avian mixed species flocks in Amazonian rainforests: flock mates (eavesdropping species) strongly associate with alarm-calling antshrikes (genus Thamnomanes), which act as sentinel species. Up to 70 species join these flocks, presumably following antshrike behavioral cues. Since flocks in this region of the Amazon are exclusively led by a single antshrike species, this provides a unique natural system to compare differences in sentinel quality between flocks. We simulated predation threat by flying three species of live trained raptors (predators) towards flocks to compare sentinel probability to (1) produce alarm calls, and (2) encode information about magnitude and type of threat within such alarm calls. Our field experiments show significant differences in the probability of different sentinel species to produce alarm calls and distinguish predators. This variation may have important fitness consequences and shape the "landscape of fear" for eavesdropping species.
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Affiliation(s)
- A E Martínez
- Department of Biology, San Francisco State University, 1600 Holloway Ave., San Francisco, California, 94132, USA
| | - E Parra
- Department of Biology, San Francisco State University, 1600 Holloway Ave., San Francisco, California, 94132, USA
| | - L F Collado
- Colka Raptors SAC, Mza. C Lote 10-L Urb. San Eduardo Piura, Piura, Peru
| | - V T Vredenburg
- Department of Biology, San Francisco State University, 1600 Holloway Ave., San Francisco, California, 94132, USA
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23
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Latimer CE, Cooper SJ, Karasov WH, Zuckerberg B. Does habitat fragmentation promote climate-resilient phenotypes? OIKOS 2018. [DOI: 10.1111/oik.05111] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Christopher E. Latimer
- Dept of Forest and Wildlife Ecology; Univ. of Wisconsin-Madison; 226 Russell Labs 1630 Linden Drive Madison WI 53706 USA
| | | | - William H. Karasov
- Dept of Forest and Wildlife Ecology; Univ. of Wisconsin-Madison; 226 Russell Labs 1630 Linden Drive Madison WI 53706 USA
| | - Benjamin Zuckerberg
- Dept of Forest and Wildlife Ecology; Univ. of Wisconsin-Madison; 226 Russell Labs 1630 Linden Drive Madison WI 53706 USA
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Cosgrove AJ, McWhorter TJ, Maron M. Consequences of impediments to animal movements at different scales: A conceptual framework and review. DIVERS DISTRIB 2017. [DOI: 10.1111/ddi.12699] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Affiliation(s)
- Anita J. Cosgrove
- School of Earth and Environmental Sciences The University of Queensland St Lucia Qld Australia
| | - Todd J. McWhorter
- School of Animal and Veterinary Sciences The University of Adelaide Adelaide SA Australia
| | - Martine Maron
- School of Earth and Environmental Sciences The University of Queensland St Lucia Qld Australia
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25
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Carlson NV, Pargeter HM, Templeton CN. Sparrowhawk movement, calling, and presence of dead conspecifics differentially impact blue tit ( Cyanistes caeruleus) vocal and behavioral mobbing responses. Behav Ecol Sociobiol 2017; 71:133. [PMID: 28860673 PMCID: PMC5558234 DOI: 10.1007/s00265-017-2361-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/27/2017] [Accepted: 07/31/2017] [Indexed: 11/25/2022]
Abstract
ABSTRACT Many animals alter their anti-predator behavior in accordance to the threat level of a predator. While much research has examined variation in mobbing responses to different predators, few studies have investigated how anti-predator behavior is affected by changes in a predator's own state or behavior. We examined the effect of sparrowhawk (Accipiter nisus) behavior on the mobbing response of wild blue tits (Cyanistes caeruleus) using robotic taxidermy sparrowhawks. We manipulated whether the simulated predator moved its head, produced vocalizations, or held a taxidermy blue tit in its talons. When any sparrowhawk model was present, blue tits decreased foraging and increased anti-predator behavior and vocalizations. Additionally, each manipulation of the model predator's state (moving, vocalizing, or the presence of a dead conspecific) impacted different types of blue tit anti-predator behavior and vocalizations. These results indicate that different components of mobbing vary according to the specific state of a given predator-beyond its presence or absence-and suggest that each might play a different role in the overall mobbing response. Last, our results indicate that using more life-like predator stimuli-those featuring simple head movements and audio playback of vocalizations-changes how prey respond to the predator; these 'robo-raptor' models provide a powerful tool to provide increased realism in simulated predator encounters without sacrificing experimental control. SIGNIFICANCE STATEMENT Anti-predatory behavior is often modulated by the threat level posed by a particular predator. While much research has tested how different types of predators change prey behavior, few experiments have examined how predator behavior affects anti-predatory responses of prey. By experimentally manipulating robotic predators, we show that blue tits not only respond to the presence of a sparrowhawk, by decreasing feeding and increasing anti-predator behavior and vocalizations, but that they vary specific anti-predator behaviors when encountering differently behaving predators (moving, vocalizing, or those with captured prey), suggesting that prey pay attention to their predators' state and behavior.
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Affiliation(s)
- Nora V. Carlson
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
| | - Helen M. Pargeter
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
- Present Address: Departament de Biologia Animal (Vertebrats), Universitat de Barcelona, 08028 Barcelona, Spain
| | - Christopher N. Templeton
- School of Biology, University of St Andrews, Harold Mitchell Building, St Andrews, Fife, Scotland KY16 9TH UK
- Department of Biology, Pacific University, 2043 College Way, Forest Grove, Oregon, 97116 USA
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26
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Biz M, Cornelius C, Metzger JPW. Matrix type affects movement behavior of a Neotropical understory forest bird. Perspect Ecol Conserv 2017. [DOI: 10.1016/j.pecon.2017.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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27
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Scriven SA, Beale CM, Benedick S, Hill JK. Barriers to dispersal of rain forest butterflies in tropical agricultural landscapes. Biotropica 2016. [DOI: 10.1111/btp.12397] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Colin M. Beale
- Department of Biology; University of York; York YO10 5DD UK
| | - Suzan Benedick
- Faculty of Sustainable Agriculture; Universiti Malaysia Sabah; Beg Berkunci No. 3 90509 Sandakan Sabah Malaysia
| | - Jane K. Hill
- Department of Biology; University of York; York YO10 5DD UK
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Conley MD, Yeldell NA, Chamberlain MJ, Collier BA. Do movement behaviors identify reproductive habitat sampling for wild turkeys? Ecol Evol 2016; 6:7103-7112. [PMID: 28725385 PMCID: PMC5513226 DOI: 10.1002/ece3.2401] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 07/27/2016] [Accepted: 08/04/2016] [Indexed: 11/24/2022] Open
Abstract
Selection of habitats has regularly been suggested to influence species demography at both local and broad scales. The expectation is that selection behaviors have positive benefits via greater fitness or increased survival. The current paradigm of habitat selection theory suggests a hierarchical process, where an individual first selects where they choose to live (e.g., range) and then searches and selects locations within this range meeting life history needs. Using high‐frequency GPS data collected from reproductively active Rio Grande (n = 21) and Eastern (n = 23) wild turkeys, we evaluated a long‐standing theory for ground‐nesting galliformes, in that movements during the prenesting period are behaviorally focused on sampling available habitats to optimize the selection of nesting sites. Contrary to expectations, we found no evidence that reproductively active females engage in habitat sampling activities. Although most nest sites (>80% for both subspecies) fell within the prenesting range, the average minimum daily distance from nest sites for Rio Grande and Eastern wild turkey females was large [1636.04 m (SE = 1523.96) and 1937.42 m (SE = 1267.84), respectively] whereas the average absolute minimum distance from the nest site for both Rio Grande and Eastern wild turkey females was 166.46 m (SE = 299.34) and 235.01 m (SE = 337.90), respectively, and showed no clear temporal reduction as laying approached. Overall, predicted probability that any female movements before laying were initiated intersected with her nesting range (area used during incubation) was <0.25, indicating little evidence of habitat sampling. Our results suggest that the long‐standing assumption of hierarchical habitat selection by wild turkeys to identify nest sites may be incorrect. As such, habitat selection may not be the proximate driver of nest success and hence population‐level fitness. Rather, based on our results, we suggest that wild turkeys and other ground‐nesting species may be fairly plastic with regard to the selection of reproductive habitats, which is appropriate given the stochasticity of the environments they inhabit.
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Affiliation(s)
- Mason D Conley
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas 77845
| | - Nathan A Yeldell
- Warnell School of Forestry and Natural Resources University of Georgia Athens Georgia 30602
| | - Michael J Chamberlain
- Warnell School of Forestry and Natural Resources University of Georgia Athens Georgia 30602
| | - Bret A Collier
- School of Renewable Natural Resources Louisiana State University Agricultural Center Baton Rouge Louisiana 70803
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Santos PM, Chiarello AG, Ribeiro MC, Ribeiro JW, Paglia AP. Local and landscape influences on the habitat occupancy of the endangered maned sloth Bradypus torquatus within fragmented landscapes. Mamm Biol 2016. [DOI: 10.1016/j.mambio.2016.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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Brauze T, Zieliński J. Do forest birds take the risk of feeding in an open area in winter? Experiment with extra food gradually moved away from the edge of the forest into the open area. RUSS J ECOL+ 2016. [DOI: 10.1134/s1067413616020053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Kern JM, Radford AN. Sentinel dwarf mongooses, Helogale parvula, exhibit flexible decision making in relation to predation risk. Anim Behav 2014. [DOI: 10.1016/j.anbehav.2014.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Roy CL, Fieberg J, Scharenbroich C, Herwig CM. Thinking like a duck: fall lake use and movement patterns of juvenile ring-necked ducks before migration. PLoS One 2014; 9:e88597. [PMID: 24551123 PMCID: PMC3925105 DOI: 10.1371/journal.pone.0088597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 01/12/2014] [Indexed: 11/30/2022] Open
Abstract
The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall.
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Affiliation(s)
- Charlotte L. Roy
- Wetland Wildlife Populations and Research Group, Minnesota Department of Natural Resources, Bemidji, Minnesota, United States of America
| | - John Fieberg
- Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, St. Paul, Minnesota, United States of America
| | | | - Christine M. Herwig
- Minnesota Department of Natural Resources, Bemidji, Minnesota, United States of America
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33
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Gow EA, Wiebe KL. Survival and habitat use by fledgling northern flickers in a fragmented forest landscape. J Wildl Manage 2014. [DOI: 10.1002/jwmg.657] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Elizabeth A. Gow
- Department of Biology; University of Saskatchewan; 112 Science Place Saskatoon Saskatchewan S7N 5E2 Canada
| | - Karen L. Wiebe
- Department of Biology; University of Saskatchewan; 112 Science Place Saskatoon Saskatchewan S7N 5E2 Canada
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Fernández Ferrari MC, Schausberger P. From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues. Naturwissenschaften 2013; 100:541-9. [PMID: 23644512 DOI: 10.1007/s00114-013-1050-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 11/25/2022]
Abstract
Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.
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Affiliation(s)
- M Celeste Fernández Ferrari
- Group of Arthropod Ecology and Behavior, Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Peter Jordanstrasse 82, 1190, Vienna, Austria
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35
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Sorato E, Gullett PR, Griffith SC, Russell AF. Effects of predation risk on foraging behaviour and group size: adaptations in a social cooperative species. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.07.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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36
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Lasky JR, Keitt TH. The Effect of Spatial Structure of Pasture Tree Cover on Avian Frugivores in Eastern Amazonia. Biotropica 2012. [DOI: 10.1111/j.1744-7429.2012.00857.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Jesse R. Lasky
- Section of Integrative Biology; University of Texas at Austin; 1 University Station A6700; 78712-0253; Austin; Texas
| | - Timothy H. Keitt
- Section of Integrative Biology; University of Texas at Austin; 1 University Station A6700; 78712-0253; Austin; Texas
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MacIntosh T, Stutchbury B, Evans M. Gap-crossing by Wood Thrushes (Hylocichla mustelina)in a fragmented landscape. CAN J ZOOL 2011. [DOI: 10.1139/z11-090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We used radio-telemetry to study the movement patterns of Wood Thrushes ( Hylocichla mustelina (J.F. Gmelin, 1789)) occupying small forest fragments (<5 ha) to examine gap-crossing between fragments and edge use within fragments. We found that 82% (8/11) of males and 33% (2/6) of females made at least one foray off of its resident forest fragment and we documented a total of 26 off-fragment forays (n = 79 h tracking). Males spent, on average, 23.5% of their time off their fragment, while females were gone 12.8% of the time tracked. Most forays were >150 m in distance and foray rate to adjacent fragments declined with increasing gap width. Males on fragments spent more time off their territory (23.5%) and traveled farther (392 m) than males occupying territories within a continuous forest (4.8% and 99 m, respectively). In fragments, 10 out of 17 individuals spent >80% of their time within 20 m of the fragment edge and edge use was significantly more than expected based on the amount of edge available in each fragment. This study adds to the growing evidence for migratory songbirds that during the breeding season, forest fragmentation may increase rather than impede daily movements.
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Affiliation(s)
- T. MacIntosh
- Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - B.J.M. Stutchbury
- Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - M.L. Evans
- Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
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Hetrick SA, Sieving KE. Antipredator calls of tufted titmice and interspecific transfer of encoded threat information. Behav Ecol 2011. [DOI: 10.1093/beheco/arr160] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Galván I, Sanz JJ. Mate-feeding has evolved as a compensatory energetic strategy that affects breeding success in birds. Behav Ecol 2011. [DOI: 10.1093/beheco/arr094] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Population genetic structure of the endangered Eastern Bristlebird, Dasyornis brachypterus; implications for conservation. CONSERV GENET 2011. [DOI: 10.1007/s10592-011-0210-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gillies CS, Beyer HL, St Clair CC. Fine-scale movement decisions of tropical forest birds in a fragmented landscape. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2011; 21:944-954. [PMID: 21639057 DOI: 10.1890/09-2090.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The persistence of forest-dependent species in fragmented landscapes is fundamentally linked to the movement of individuals among subpopulations. The paths taken by dispersing individuals can be considered a series of steps built from individual route choices. Despite the importance of these fine-scale movement decisions, it has proved difficult to collect such data that reveal how forest birds move in novel landscapes. We collected unprecedented route information about the movement of translocated forest birds from two species in the highly fragmented tropical dry forest of Costa Rica. In this pasture-dominated landscape, forest remains in patches or riparian corridors, with lesser amounts of living fencerows and individual trees or "stepping stones." We used step selection functions to quantify how route choice was influenced by these habitat elements. We found that the amount of risk these birds were willing to take by crossing open habitat was context dependent. The forest-specialist Barred Antshrike (Thamnophilus doliatus) exhibited stronger selection for forested routes when moving in novel landscapes distant from its territory relative to locations closer to its territory. It also selected forested routes when its step originated in forest habitat. It preferred steps ending in stepping stones when the available routes had little forest cover, but avoided them when routes had greater forest cover. The forest-generalist Rufous-naped Wren (Campylorhynchus rufinucha) preferred steps that contained more pasture, but only when starting from non-forest habitats. Our results showed that forested corridors (i.e., riparian corridors) best facilitated the movement of a sensitive forest specialist through this fragmented landscape. They also suggested that stepping stones can be important in highly fragmented forests with little remaining forest cover. We expect that naturally dispersing birds and species with greater forest dependence would exhibit even stronger selection for forested routes than did the birds in our experiments.
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Affiliation(s)
- Cameron S Gillies
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
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Tremblay MA, St. Clair CC. Permeability of a heterogeneous urban landscape to the movements of forest songbirds. J Appl Ecol 2011. [DOI: 10.1111/j.1365-2664.2011.01978.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Braña F, Prieto L, González-Quirós P. Habitat Change and Timing of Dusk Flight in the Eurasian Woodcock: A Trade-Off between Feeding and Predator Avoidance? ANN ZOOL FENN 2010. [DOI: 10.5735/086.047.0305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
AbstractForestry practices may directly kill animals as well as destroy and fragment their habitat. Even without habitat destruction, logging and its associated forest management practices (which include road building, re-forestation, and often increased recreational use) create noise, frighten animals, and may lead to changes in species composition as well as evolutionary responses to the myriad of anthropogenic impacts. Thus, forestry practices may create conservation problems. Forestry practices may also create welfare problems that may act on different temporal and spatial scales than the conservation problems. The individuals affected by forestry may have heightened glucocorticoid levels that may lead to a predictable set of deleterious consequences. Individuals may no longer be able to communicate, or they may no longer be attractive to potential mates. Such welfare problems may generate conservation problems if fitness is reduced. Identifying the set of possible impacts is the first step towards improving welfare and aiding wildlife conservation in managed forests.
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Newmark WD, Mkongewa VJ, Sobek AD. Ranging behavior and habitat selection of terrestrial insectivorous birds in north-east Tanzania: implications for corridor design in the Eastern Arc Mountains. Anim Conserv 2010. [DOI: 10.1111/j.1469-1795.2010.00366.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pierson JC, Allendorf FW, Saab V, Drapeau P, Schwartz MK. Do male and female black-backed woodpeckers respond differently to gaps in habitat? Evol Appl 2010; 3:263-78. [PMID: 25567923 PMCID: PMC3352463 DOI: 10.1111/j.1752-4571.2009.00111.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 10/26/2009] [Indexed: 11/29/2022] Open
Abstract
We used population- and individual-based genetic approaches to assess barriers to movement in black-backed woodpeckers (Picoides arcticus), a fire-specialist that mainly occupies the boreal forest in North America. We tested if male and female woodpeckers exhibited the same movement patterns using both spatially implicit and explicit genetic analyses to define population structure and movement patterns of both sexes among populations. Three genetic groups were identified, a large, genetically continuous population that spans from the Rocky Mountains to Quebec, a small isolated population in South Dakota and a separate population in the western portion of their distribution (Oregon). Patterns of genetic diversity suggest extensive gene flow mediated by both males and females within the continuous boreal forest. However, male-mediated gene flow is the main form of connectivity between the continuously distributed group and the smaller populations of South Dakota and Oregon that are separated by large areas of unforested habitat, which apparently serves as a barrier to movement of female woodpeckers.
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Affiliation(s)
| | - Fred W Allendorf
- Division of Biological Sciences, University of Montana Missoula, MT, USA
| | - Victoria Saab
- USDA Forest Service, Rocky Mountain Research Station Bozeman, MT, USA
| | - Pierre Drapeau
- Département des Sciences Biologiques, Université du Québec à Montréal Montréal, QC, Canada
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Tremblay MA, St. Clair CC. Factors affecting the permeability of transportation and riparian corridors to the movements of songbirds in an urban landscape. J Appl Ecol 2009. [DOI: 10.1111/j.1365-2664.2009.01717.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Riparian corridors enhance movement of a forest specialist bird in fragmented tropical forest. Proc Natl Acad Sci U S A 2008; 105:19774-9. [PMID: 19017794 DOI: 10.1073/pnas.0803530105] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Riparian corridors and fencerows are hypothesized to increase the persistence of forest animals in fragmented landscapes by facilitating movement among suitable habitat patches. This function may be critically important for forest birds, which have declined dramatically in fragmented habitats. Unfortunately, direct evidence of corridor use has been difficult to collect at landscape scales and this limits support for corridors in conservation planning. Using telemetry and handheld GPS units, we examined the movement of forest birds by translocating territorial individuals of barred antshrikes (Thamnophilus doliatus; a forest specialist) and rufous-naped wrens (Campylorhynchus rufinucha; a forest generalist) 0.7-1.9 km from their territories in the highly fragmented tropical dry forest of Costa Rica. In each translocation, the directly intervening habitat comprised 1 of 3 treatments: forested riparian corridor, linear living fencerow, or open pasture. Antshrikes returned faster and with greater success in riparian corridors relative to pasture treatments. This species also traveled more directly in riparian corridor treatments, detoured to use forested routes in the other 2 treatments, and did not use fencerows even when they led directly to their home territories. By contrast, wrens were more likely to use fencerows when returning, and return time and success were equivalent among the 3 treatments. Both species crossed fewer gaps in tree cover during riparian corridor treatments than in fencerow or pasture treatments. We conclude that antshrikes, which may be representative of other forest specialists, use forested corridors for movement in this landscape and that fencerows are avoided as movement conduits.
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Gobeil JF, Villard MA. Permeability of three boreal forest landscape types to bird movements as determined from experimental translocations. OIKOS 2008. [DOI: 10.1034/j.1600-0706.2002.980309.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Rodríguez A, Jansson G, Andrén H. Composition of an avian guild in spatially structured habitats supports a competition-colonization trade-off. Proc Biol Sci 2007; 274:1403-11. [PMID: 17389222 PMCID: PMC2176207 DOI: 10.1098/rspb.2007.0104] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Assuming better colonization abilities of inferior competitors, the competition-colonization trade-off (CCTO) is one of the hypotheses that explains spatial variation of species composition in fragmented habitats. Whereas this mechanism may structure some plant and insect communities, ecologists have failed to document its operation in other natural systems, and its generality has been questioned. We combined fieldwork and published data to study the composition of a guild of passerines (Parus cristatus, Parus montanus, Parus ater and Regulus regulus) inhabiting 10 landscapes that differed in the amount of forest habitat. The species were ordered in a stable, well-defined competitive hierarchy, and the dispersal ability of each species was inversely correlated with its position in this hierarchy. In functionally continuous landscapes, superior competitors occupied most fragments and all guild members commonly occurred. The relative incidences of superior and inferior competitors were reversed, and differences amplified, in landscapes where patches were physically (distance) or functionally (matrix hardness) isolated. We found little support for two competing hypotheses, namely reduced habitat quality in isolated patches and lower abundance of a keystone predator (Glaucidium passerinum) in fragmented landscapes. We concluded that the CCTO offered the most probable explanation for variation in the composition of the Parus guild across landscapes.
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Affiliation(s)
- Alejandro Rodríguez
- Department of Conservation Biology, Estación Biológica de Doñana, CSIC, Avenida María Luisa s/n, 41013 Sevilla, Spain.
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