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Burner RC, Golas BD, Aagaard KJ, Lonsdorf EV, Thogmartin WE. Marginal value analysis reveals shifting importance of migration habitat for waterfowl under a changing climate. Ecol Evol 2023; 13:e10632. [PMID: 37953991 PMCID: PMC10636373 DOI: 10.1002/ece3.10632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 09/22/2023] [Accepted: 10/06/2023] [Indexed: 11/14/2023] Open
Abstract
Migratory waterfowl are an important resource for consumptive and non-consumptive users alike and provide tremendous economic value in North America. These birds rely on a complex matrix of public and private land for forage and roosting during migration and wintering periods, and substantial conservation effort focuses on increasing the amount and quality of target habitat. Yet, the value of habitat is a function not only of a site's resources but also of its geographic position and weather. To quantify this value, we used a continental-scale energetics-based model of daily dabbling duck movement to assess the marginal value of lands across the contiguous United States during the non-breeding period (September to May). We examined effects of eliminating each habitat node (32 × 32 km) in both a particularly cold and a particularly warm winter, asking which nodes had the largest effect on survival. The marginal value of habitat nodes for migrating dabbling ducks was a function of forage and roosting habitat but, more importantly, of geography (especially latitude and region). Irrespective of weather, nodes in the Southeast, central East Coast, and California made the largest positive contributions to survival. Conversely, nodes in the Midwest, Northeast, Florida, and the Pacific Northwest had consistent negative effects. Effects (positive and negative) of more northerly nodes occurred in late fall or early spring when climate was often severe and was most variable. Importance and effects of many nodes varied considerably between a cold and a warm winter. Much of the Midwest and central Great Plains benefited duck survival in a warm winter, and projected future warming may improve the value of lands in these regions, including many National Wildlife Refuges, for migrating dabbling ducks. Our results highlight the geographic variability in habitat value, as well as shifts that may occur in these values due to climate change.
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Affiliation(s)
- Ryan C. Burner
- U.S. Geological SurveyUpper Midwest Environmental Sciences CenterLa CrosseWisconsinUSA
| | - Benjamin D. Golas
- U.S. Geological SurveyUpper Midwest Environmental Sciences CenterLa CrosseWisconsinUSA
- Department of BiologyColorado State UniversityFort CollinsColoradoUSA
| | | | - Eric V. Lonsdorf
- Department of Environmental SciencesEmory UniversityAtlantaGeorgiaUSA
| | - Wayne E. Thogmartin
- U.S. Geological SurveyUpper Midwest Environmental Sciences CenterLa CrosseWisconsinUSA
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Wild Bird Surveillance in the Gauteng Province of South Africa during the High-Risk Period for Highly Pathogenic Avian Influenza Virus Introduction. Viruses 2022; 14:v14092027. [PMID: 36146838 PMCID: PMC9504564 DOI: 10.3390/v14092027] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/08/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
Migratory birds carried clade 2.3.4.4B H5Nx highly pathogenic avian influenza (HPAI) viruses to South Africa in 2017, 2018 and 2021, where the Gauteng Province is a high-risk zone for virus introduction. Here, we combined environmental faecal sampling with sensitive rRT-PCR methods and direct Ion Torrent sequencing to survey wild populations between February and May 2022. An overall IAV incidence of 42.92% (100/231) in water bird faecal swab pools or swabs from moribund or dead European White Storks (Ciconia ciconia) was detected. In total, 7% of the IAV-positive pools tested H5-positive, with clade 2.3.4.4B H5N1 HPAI confirmed in the storks; 10% of the IAV-positive samples were identified as H9N2, and five complete H9N2 genomes were phylogenetically closely related to a local 2021 wild duck H9N2 virus, recent Eurasian LPAI viruses or those detected in commercial ostriches in the Western and Eastern Cape Provinces since 2018. H3N1, H4N2, H5N2 and H8Nx subtypes were also identified. Targeted surveillance of wild birds using environmental faecal sampling can thus be effectively applied under sub-Saharan African conditions, but region-specific studies should first be used to identify peak prevalence times which, in southern Africa, is linked to the peak rainfall period, when ducks are reproductively active.
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Stukenholtz EE, Stevens RD. Taxonomic and functional components of avian metacommunity structure along an urban gradient. PLoS One 2022; 17:e0271405. [PMID: 35944024 PMCID: PMC9362948 DOI: 10.1371/journal.pone.0271405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/29/2022] [Indexed: 11/18/2022] Open
Abstract
Identifying biological processes that structure natural communities has long interested ecologists. Community structure may be determined by various processes, including differential responses of species to environmental characteristics, regional-level spatial influences such as dispersal, or stochasticity generated from ecological drift. Few studies have used the metacommunity paradigm (interacting communities linked by dispersal) to investigate avian community composition along an urban gradient, yet such a theoretical construct may provide insights into species turnover even in unnatural settings such as rural to urban gradients. We measured the influence of spatial and environmental characteristics on two aspects of avian community structure across a gradient of urbanization: 1) taxonomic composition and 2) functional richness based on diet, foraging strategies, nesting locations and morphology. We also measured the relationship between species traits and environmental variables with an RLQ-fourth corner analysis. Together, environmental and spatial processes were significantly related to taxonomic structure and functional richness, but spatial variables accounted for more variation than environmental variables. Fine spatial scales were positively correlated with insectivorous birds and negatively correlated with body and wing size. Urbanization was positively correlated with birds that forage at the canopy level, while emergent wetlands were negatively correlated with birds that nested in cliffs and frugivorous birds. Functional richness and urbanization were significantly related to fine spatial variables. Spatial and environmental factors played an important role in taxonomic and functional structure in avian metacommunity structure. This study highlights the importance of studying multiple aspects of biodiversity, such as taxonomic and functional dimensions, especially when examining effects of complementary spatial and environmental processes.
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Affiliation(s)
- Erin E. Stukenholtz
- Department of Natural Resources Management, Texas Tech University, Lubbock, TX, United States of America
- * E-mail:
| | - Richard D. Stevens
- Department of Natural Resources Management, Texas Tech University, Lubbock, TX, United States of America
- Natural Science Research Laboratory of the Museum of Texas Tech University, Lubbock, TX, United States of America
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Cumming GS, Henry DAW, Reynolds C. Translocation experiment gives new insights into the navigation capacity of an African duck. DIVERS DISTRIB 2022. [DOI: 10.1111/ddi.13510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Graeme S. Cumming
- ARC Centre of Excellence for Coral Reef Studies James Cook University Townsville Queensland Australia
- DST/NRF Centre of Excellence at the FitzPatrick Institute University of Cape Town Cape Town South Africa
| | - Dominic A. W. Henry
- DST/NRF Centre of Excellence at the FitzPatrick Institute University of Cape Town Cape Town South Africa
- Statistics in Ecology, Environment and Conservation Department of Statistical Sciences University of Cape Town Cape Town South Africa
- Endangered Wildlife Trust Johannesburg South Africa
| | - Chevonne Reynolds
- DST/NRF Centre of Excellence at the FitzPatrick Institute University of Cape Town Cape Town South Africa
- Animal, Plant and Environmental Sciences University of the Witwatersrand Johannesburg South Africa
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Kahara SN, Skalos D, Madurapperuma B, Hernandez K. Habitat quality and drought effects on breeding mallard and other waterfowl populations in California, USA. J Wildl Manage 2022. [DOI: 10.1002/jwmg.22133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Sharon N. Kahara
- University of New Haven 300 Boston Post Road West Haven 06516 CT USA
| | - Daniel Skalos
- California Department of Fish and Wildlife 1416 9th Street, 12th Floor Sacramento 95814 CA USA
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Changes in surface water drive the movements of Shoebills. Sci Rep 2021; 11:15796. [PMID: 34349159 PMCID: PMC8338928 DOI: 10.1038/s41598-021-95093-5] [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: 01/25/2021] [Accepted: 07/05/2021] [Indexed: 02/07/2023] Open
Abstract
Animal movement is mainly determined by spatial and temporal changes in resource availability. For wetland specialists, the seasonal availability of surface water may be a major determinant of their movement patterns. This study is the first to examine the movements of Shoebills (Balaeniceps rex), an iconic and vulnerable bird species. Using GPS transmitters deployed on six immature and one adult Shoebills over a 5-year period, during which four immatures matured into adults, we analyse their home ranges and distances moved in the Bangweulu Wetlands, Zambia. We relate their movements at the start of the rainy season (October to December) to changes in Normalized Difference Water Index (NDWI), a proxy for surface water. We show that Shoebills stay in the Bangweulu Wetlands all year round, moving less than 3 km per day on 81% of days. However, average annual home ranges were large, with high individual variability, but were similar between age classes. Immature and adult Shoebills responded differently to changes in surface water; sites that adults abandoned became drier, while sites abandoned by immatures became wetter. However, there were no differences in NDWI of areas used by Shoebills before abandonment and newly selected sites, suggesting that Shoebills select areas with similar surface water. We hypothesise that the different responses to changes in surface water by immature and adult Shoebills are related to age-specific optimal foraging conditions and fishing techniques. Our study highlights the need to understand the movements of Shoebills throughout their life cycle to design successful conservation actions for this emblematic, yet poorly known, species.
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VonBank JA, Weegman MD, Link PT, Cunningham SA, Kraai KJ, Collins DP, Ballard BM. Winter fidelity, movements, and energy expenditure of Midcontinent Greater White-fronted Geese. MOVEMENT ECOLOGY 2021; 9:2. [PMID: 33472671 PMCID: PMC7816378 DOI: 10.1186/s40462-020-00236-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/14/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Animal movement patterns are the result of both environmental and physiological effects, and the rates of movement and energy expenditure of given movement strategies are influenced by the physical environment an animal inhabits. Greater white-fronted geese in North America winter in ecologically distinct regions and have undergone a large-scale shift in wintering distribution over the past 20 years. White-fronts continue to winter in historical wintering areas in addition to contemporary areas, but the rates of movement among regions, and energetic consequences of those decisions, are unknown. Additionally, linkages between wintering and breeding regions are generally unknown, and may influence within-winter movement rates. METHODS We used Global Positioning System and acceleration data from 97 white-fronts during two winters to elucidate movement characteristics, model regional transition probabilities using a multistate model in a Bayesian framework, estimate regional energy expenditure, and determine behavior time-allocation influences on energy expenditure using overall dynamic body acceleration and linear mixed-effects models. We assess the linkages between wintering and breeding regions by evaluating the winter distributions for each breeding region. RESULTS White-fronts exhibited greater daily movement early in the winter period, and decreased movements as winter progressed. Transition probabilities were greatest towards contemporary winter regions and away from historical wintering regions. Energy expenditure was up to 55% greater, and white-fronts spent more time feeding and flying, in contemporary wintering regions compared to historical regions. White-fronts subsequently summered across their entire previously known breeding distribution, indicating substantial mixing of individuals of varying breeding provenance during winter. CONCLUSIONS White-fronts revealed extreme plasticity in their wintering strategy, including high immigration probability to contemporary wintering regions, high emigration from historical wintering regions, and high regional fidelity to western regions, but frequent movements among eastern regions. Given that movements of white-fronts trended toward contemporary wintering regions, we anticipate that a wintering distribution shift eastward will continue. Unexpectedly, greater energy expenditure in contemporary wintering regions revealed variable energetic consequences of choice in wintering region and shifting distribution. Because geese spent more time feeding in contemporary regions than historical regions, increased energy expenditure is likely balanced by increased energy acquisition in contemporary wintering areas.
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Affiliation(s)
- Jay A VonBank
- Caesar Kleberg Wildlife Research Institute, Texas A&M University - Kingsville, Kingsville, TX, 78363, USA.
- Present Address: U.S. Geological Survey, Northern Prairie Wildlife Research Center, Jamestown, ND, 58401, USA.
| | - Mitch D Weegman
- School of Natural Resources, University of Missouri, Columbia, MO, 65211, USA
| | - Paul T Link
- Louisiana Department of Wildlife and Fisheries, Baton Rouge, LA, 70808, USA
| | | | - Kevin J Kraai
- Texas Parks and Wildlife Department, Canyon, TX, 79015, USA
| | | | - Bart M Ballard
- Caesar Kleberg Wildlife Research Institute, Texas A&M University - Kingsville, Kingsville, TX, 78363, USA
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Multi-source data fusion of optical satellite imagery to characterize habitat selection from wildlife tracking data. ECOL INFORM 2020. [DOI: 10.1016/j.ecoinf.2020.101149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Pretorius MD, Leeuwner L, Tate GJ, Botha A, Michael MD, Durgapersad K, Chetty K. Movement patterns of lesser flamingos Phoeniconaias minor: nomadism or partial migration? WILDLIFE BIOLOGY 2020. [DOI: 10.2981/wlb.00728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Mattheuns D. Pretorius
- M. D. Pretorius (https://orcid.org/0000-0001-9010-7597) ✉ , L. Leeuwner (https://orcid.org/0000-0002-5562-6225), G. J. Tate (https://orcid.org/0000-0002-1816-317X) and A. Botha (https://orcid.org/0000-0003-1077-1215), The Endangered
| | - Lourens Leeuwner
- M. D. Pretorius (https://orcid.org/0000-0001-9010-7597) ✉ , L. Leeuwner (https://orcid.org/0000-0002-5562-6225), G. J. Tate (https://orcid.org/0000-0002-1816-317X) and A. Botha (https://orcid.org/0000-0003-1077-1215), The Endangered
| | - Gareth J. Tate
- M. D. Pretorius (https://orcid.org/0000-0001-9010-7597) ✉ , L. Leeuwner (https://orcid.org/0000-0002-5562-6225), G. J. Tate (https://orcid.org/0000-0002-1816-317X) and A. Botha (https://orcid.org/0000-0003-1077-1215), The Endangered
| | - André Botha
- M. D. Pretorius (https://orcid.org/0000-0001-9010-7597) ✉ , L. Leeuwner (https://orcid.org/0000-0002-5562-6225), G. J. Tate (https://orcid.org/0000-0002-1816-317X) and A. Botha (https://orcid.org/0000-0003-1077-1215), The Endangered
| | - Michael D. Michael
- M. D. Michael, K. Durgapersad (https://orcid.org/0000-0001-9008-3652) and K. Chetty (https://orcid.org/0000-0003-1374-1206), Eskom Holdings SOC Ltd., Sunninghill, South Africa
| | - Kaajial Durgapersad
- M. D. Michael, K. Durgapersad (https://orcid.org/0000-0001-9008-3652) and K. Chetty (https://orcid.org/0000-0003-1374-1206), Eskom Holdings SOC Ltd., Sunninghill, South Africa
| | - Kishaylin Chetty
- M. D. Michael, K. Durgapersad (https://orcid.org/0000-0001-9008-3652) and K. Chetty (https://orcid.org/0000-0003-1374-1206), Eskom Holdings SOC Ltd., Sunninghill, South Africa
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Utsumi K, Kusaka C, Pedersen R, Staley C, Dunlap L, Smith SG, Eifler MA, Eifler DA. Habitat-Dependent Search Behavior in the Colorado Checkered Whiptail (Aspidoscelis neotesselata). WEST N AM NATURALIST 2020. [DOI: 10.3398/064.080.0102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
| | - Carina Kusaka
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523
| | - Rachael Pedersen
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523
| | - Catherine Staley
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523
| | - Lisa Dunlap
- Undergraduate Mathematics Program, University of California, Berkeley, CA 94702
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McDuie F, Casazza ML, Overton CT, Herzog MP, Hartman CA, Peterson SH, Feldheim CL, Ackerman JT. GPS tracking data reveals daily spatio-temporal movement patterns of waterfowl. MOVEMENT ECOLOGY 2019; 7:6. [PMID: 30834128 PMCID: PMC6388499 DOI: 10.1186/s40462-019-0146-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/07/2019] [Indexed: 05/07/2023]
Abstract
BACKGROUND Spatio-temporal patterns of movement can characterize relationships between organisms and their surroundings, and address gaps in our understanding of species ecology, activity budgets, bioenergetics, and habitat resource management. Highly mobile waterfowl, which can exploit resources over large spatial extents, are excellent models to understand relationships between movements and resource usage, landscape interactions and specific habitat needs. METHODS We tracked 3 species of dabbling ducks with GPS-GSM transmitters in 2015-17 to examine fine-scale movement patterns over 24 h periods (30 min interval), dividing movement pathways into temporally continuous segments and spatially contiguous patches. We quantified distances moved, area used and time allocated across the day, using linear and generalized linear mixed models. We investigated behavior through relationships between these variables. RESULTS Movements and space-use were small, and varied by species, sex and season. Gadwall (Mareca strepera) generally moved least (FFDs: 0.5-0.7 km), but their larger foraging patches resulted from longer within-area movements. Pintails (Anas acuta) moved most, were more likely to conduct flights > 300 m, had FFDs of 0.8-1.1 km, used more segments and patches per day that they revisited more frequently, resulting in the longest daily total movements. Females and males differed only during the post-hunt season when females moved more. 23.6% of track segments were short duration (1-2 locations), approximately 1/3 more than would be expected if they occurred randomly, and were more dispersed in the landscape than longer segments. Distance moved in 30 min shortened as segment duration increased, likely reflecting phases of non-movement captured within segments. CONCLUSIONS Pacific Flyway ducks spend the majority of time using smaller foraging and resting areas than expected or previously reported, implying that foraging areas may be highly localized, and nutrients obtainable from smaller areas. Additionally, movement reductions over time demonstrates behavioral adjustments that represent divergent energetic demands, the detection of which is a key advantage of higher frequency data. Ducks likely use less energy for movement than currently predicted and management, including distribution and configuration of essential habitat, may require reconsideration. Our study illustrates how fine-scale movement data from tracking help understand and inform various other fields of research.
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Affiliation(s)
- Fiona McDuie
- San Jose State University Research Foundation, Moss Landing Marine Laboratories, 8272 Moss Landing Rd, Moss Landing, CA 95039 USA
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - Michael L. Casazza
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - Cory T. Overton
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - Mark P. Herzog
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - C. Alexander Hartman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - Sarah H. Peterson
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
| | - Cliff L. Feldheim
- California Department of Water Resources, Suisun Marsh Program, 3500 Industrial Blvd, #131, West Sacramento, 95691 CA USA
| | - Joshua T. Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620 USA
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Pedler RD, Ribot RFH, Bennett ATD. Long-distance flights and high-risk breeding by nomadic waterbirds on desert salt lakes. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2018; 32:216-228. [PMID: 28981964 DOI: 10.1111/cobi.13007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 06/08/2017] [Indexed: 06/07/2023]
Abstract
Understanding and conserving mobile species presents complex challenges, especially for animals in stochastic or changing environments. Nomadic waterbirds must locate temporary water in arid biomes where rainfall is highly unpredictable in space and time. To achieve this they need to travel over vast spatial scales and time arrival to exploit pulses in food resources. How they achieve this is an enduring mystery. We investigated these challenges in the colonial-nesting Banded Stilt (Cladorhynchus leucocephalus), a nomadic shorebird of conservation concern. Hitherto, Banded Stilts were hypothesized to have only 1-2 chances to breed during their long lifetime, when flooding rain fills desert salt lakes, triggering mass-hatching of brine shrimp. Over 6 years, we satellite tagged 57 individuals, conducted 21 aerial surveys to detect nesting colonies on 14 Australian desert salt lakes, and analyzed 3 decades of Landsat and MODIS satellite imagery to quantify salt-lake flood frequency and extent. Within days of distant inland rainfall, Banded Stilts flew 1,000-2,000 km to reach flooded salt lakes. On arrival, females laid over half their body weight in eggs. We detected nesting episodes across the species' range at 7 times the frequency reported during the previous 80 years. Nesting colonies of thousands formed following minor floods, yet most were subsequently abandoned when the water rapidly evaporated prior to egg hatching. Satellite imagery revealed twice as many flood events sufficient for breeding-colony initiation as recorded colonies, suggesting that nesting at remote sites has been underdetected. Individuals took risk on uncertain breeding opportunities by responding to frequent minor flood events between infrequent extensive flooding, exemplifying the extreme adaptability and trade-offs of species exploiting unstable environments. The conservation challenges of nest predation by overabundant native gulls and anthropogenic modifications to salt lakes filling frequencies require investigation, as do the physiological and navigational mechanisms that enable such extreme strategies.
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Affiliation(s)
- Reece D Pedler
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, 75 Pigdons Road, Waurn Ponds, Victoria 3216, Australia
| | - Raoul F H Ribot
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, 75 Pigdons Road, Waurn Ponds, Victoria 3216, Australia
| | - Andrew T D Bennett
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, 75 Pigdons Road, Waurn Ponds, Victoria 3216, Australia
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Howison RA, Piersma T, Kentie R, Hooijmeijer JCEW, Olff H. Quantifying landscape-level land-use intensity patterns through radar-based remote sensing. J Appl Ecol 2018. [DOI: 10.1111/1365-2664.13077] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ruth A. Howison
- Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen The Netherlands
| | - Theunis Piersma
- Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen The Netherlands
- Department of Coastal Systems; NIOZ Royal Netherlands Institute for Sea Research; Utrecht University; Utrecht The Netherlands
| | - Rosemarie Kentie
- Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen The Netherlands
- Department of Zoology; University of Oxford; Oxford UK
| | - Jos C. E. W. Hooijmeijer
- Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen The Netherlands
| | - Han Olff
- Conservation Ecology Group; Groningen Institute for Evolutionary Life Sciences (GELIFES); University of Groningen; Groningen The Netherlands
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Cumming GS, Henry DAW, Reynolds C. A framework for testing assumptions about foraging scales, body mass, and niche separation using telemetry data. Ecol Evol 2017; 7:5276-5284. [PMID: 28770066 PMCID: PMC5528209 DOI: 10.1002/ece3.3078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 02/14/2017] [Accepted: 05/08/2017] [Indexed: 11/29/2022] Open
Abstract
Ecological theory predicts that if animals with very similar dietary requirements inhabit the same landscape, then they should avoid niche overlap by either exploiting food resources at different times or foraging at different spatial scales. Similarly, it is often assumed that animals that fall in different body mass modes and share the same body plan will use landscapes at different spatial scales. We developed a new methodological framework for understanding the scaling of foraging (i.e. the range and distribution of scales at which animals use their landscapes) by applying a combination of three well‐established methods to satellite telemetry data to quantify foraging patch size distributions: (1) first‐passage time analysis; (2) a movement‐based kernel density estimator; and (3) statistical comparison of resulting histograms and tests for multimodality. We demonstrate our approach using two sympatric, ecologically similar species of African ducks with quite different body masses: Egyptian Geese (actually a shelduck), and Red‐billed Teal. Contrary to theoretical predictions, the two species, which are sympatric throughout the year, foraged at almost identical spatial scales. Our results show how ecologists can use GPS tracking data to explicitly quantify and compare the scales of foraging by different organisms within an animal community. Our analysis demonstrates both a novel approach to foraging data analysis and the need for caution when making assumptions about the relationships among niche separation, diet, and foraging scale.
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Affiliation(s)
- Graeme S Cumming
- Percy FitzPatrick Institute DST/NRF Centre of Excellence University of Cape Town Rondebosch Cape Town South Africa.,ARC Centre of Excellence for Coral Reef Studies James Cook University Townsville QLD Australia
| | - Dominic A W Henry
- Percy FitzPatrick Institute DST/NRF Centre of Excellence University of Cape Town Rondebosch Cape Town South Africa.,Statistics in Ecology, Environment and Conservation Department of Statistical Sciences University of Cape Town Rondebosch Cape Town South Africa
| | - Chevonne Reynolds
- Percy FitzPatrick Institute DST/NRF Centre of Excellence University of Cape Town Rondebosch Cape Town South Africa.,Statistics in Ecology, Environment and Conservation Department of Statistical Sciences University of Cape Town Rondebosch Cape Town South Africa
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Edelhoff H, Signer J, Balkenhol N. Path segmentation for beginners: an overview of current methods for detecting changes in animal movement patterns. MOVEMENT ECOLOGY 2016; 4:21. [PMID: 27595001 PMCID: PMC5010771 DOI: 10.1186/s40462-016-0086-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 08/09/2016] [Indexed: 05/07/2023]
Abstract
Increased availability of high-resolution movement data has led to the development of numerous methods for studying changes in animal movement behavior. Path segmentation methods provide basics for detecting movement changes and the behavioral mechanisms driving them. However, available path segmentation methods differ vastly with respect to underlying statistical assumptions and output produced. Consequently, it is currently difficult for researchers new to path segmentation to gain an overview of the different methods, and choose one that is appropriate for their data and research questions. Here, we provide an overview of different methods for segmenting movement paths according to potential changes in underlying behavior. To structure our overview, we outline three broad types of research questions that are commonly addressed through path segmentation: 1) the quantitative description of movement patterns, 2) the detection of significant change-points, and 3) the identification of underlying processes or 'hidden states'. We discuss advantages and limitations of different approaches for addressing these research questions using path-level movement data, and present general guidelines for choosing methods based on data characteristics and questions. Our overview illustrates the large diversity of available path segmentation approaches, highlights the need for studies that compare the utility of different methods, and identifies opportunities for future developments in path-level data analysis.
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Affiliation(s)
- Hendrik Edelhoff
- Department of Wildlife Sciences, University of Göttingen, Büsgenweg 3, 37077 Göttingen, Germany
| | - Johannes Signer
- Department of Wildlife Sciences, University of Göttingen, Büsgenweg 3, 37077 Göttingen, Germany
| | - Niko Balkenhol
- Department of Wildlife Sciences, University of Göttingen, Büsgenweg 3, 37077 Göttingen, Germany
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