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Lasala JA, Macksey MC, Mazzarella KT, Main KL, Foote JJ, Tucker AD. Forty years of monitoring increasing sea turtle relative abundance in the Gulf of Mexico. Sci Rep 2023; 13:17213. [PMID: 37821522 PMCID: PMC10567714 DOI: 10.1038/s41598-023-43651-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/26/2023] [Indexed: 10/13/2023] Open
Abstract
Longitudinal data sets for population abundance are essential for studies of imperiled organisms with long life spans or migratory movements, such as marine turtles. Population status trends are crucial for conservation managers to assess recovery effectiveness. A direct assessment of population growth is the enumeration of nesting numbers and quantifying nesting attempts (successful nests/unsuccessful attempts) and emergence success (number of hatchlings leaving the nest) because of the substantial annual variations due to nest placement, predation, and storm activity. We documented over 133,000 sea turtle crawls for 50.9 km of Florida Gulf of Mexico coastline from 1982 to 2021 for a large loggerhead turtle nesting aggregation and a recovering remnant population of green sea turtles. Over time both species have emerged to nest significantly earlier in the year and green sea turtle nesting seasons have extended. Nest counts and hatchling production for both species have significantly increased, but the rate of emergence success of hatchlings leaving nests has not changed for loggerheads and has declined for green sea turtles. Sea level rise and coastal developments undoubtedly influence coastal habitats in the long-term, impacting nest site selection and potential recruitment from the loss of emerged hatchlings. However, the present indications for steady Gulf of Mexico recovery of loggerhead and green sea turtles counter findings of the Florida Atlantic coasts. This study indicates that effective conservation practices can be detected within time scales of 1-2 turtle generations.
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Affiliation(s)
- Jacob Andrew Lasala
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA.
| | - Melissa C Macksey
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
| | - Kristen T Mazzarella
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
| | - Kevan L Main
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
| | - Jerris J Foote
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
- Parks, Recreation and Natural Resources, Sarasota County, 1660 Ringling Boulevard, Sarasota, FL, 34236, USA
| | - Anton D Tucker
- Sea Turtle Conservation and Research Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL, 34236, USA
- Marine Science Program, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, WA, Australia
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Cooper-Mullin C, McWilliams SR. Fat Stores and Antioxidant Capacity Affect Stopover Decisions in Three of Four Species of Migratory Passerines With Different Migration Strategies: An Experimental Approach. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.762146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
During migratory stopovers, birds must make decisions about when and where to travel and these decisions are likely contingent on their fuel stores, food availability, and antioxidant capacity as well as seasonal changes in key environmental factors. We conducted a field experiment on an offshore stopover site (Block Island, Rhode Island, United States: 41°130N, 71°330W) during autumn migration to test the hypothesis that birds with greater fuel stores and non-enzymatic antioxidant capacity have shorter stopovers than lean birds with low antioxidant capacity, and to determine the extent to which this depends on migration strategy. We used a 2 × 2 factorial field experiment (two levels each of available food and dietary polyphenols) with four species of songbirds kept in captivity for 3–5 days to produce experimental groups with different fuel stores and antioxidant capacity. We attached digital VHF transmitters to assess stopover duration and departure direction using automated telemetry. Non-enzymatic antioxidant capacity increased during refueling for Red-eyed Vireos (Vireo olivaceus) and Blackpoll Warblers (Setophaga striata) fed ad lib diets, and for ad lib fed Hermit Thrushes (Catharus guttatus) supplemented with polyphenols, but not for Yellow-rumped Warblers (Setophaga coronata coronata). Glutathione peroxidase (GPx) decreased during captivity and was influenced by dietary treatment only in Red-eyed Vireos. Oxidative damage decreased during captivity for all species except Yellow-rumped Warblers. Stopover duration was shorter for Vireos and Blackpolls fed ad lib as compared to those fed maintenance. Ad lib fed Hermit Thrushes supplemented with polyphenols had shorter stopovers than those fed ad lib, as did thrushes fed at maintenance and supplemented with polyphenols compared with those fed at maintenance alone. There was no influence of condition on stopover duration for Yellow-rumped Warblers. Departure direction was not strongly related to condition, and birds primarily reoriented north when departing Block Island. Thus, fat stores and oxidative status interacted to influence the time passerines spent on stopover, and condition-dependent departure decisions were related to a bird’s migration strategy. Therefore, seasonal variation in macro- and micro-nutrient resources available for refueling at stopover sites can affect body condition and antioxidant capacity and in turn influence the timing and success of migration.
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Schmaljohann H, Eikenaar C, Sapir N. Understanding the ecological and evolutionary function of stopover in migrating birds. Biol Rev Camb Philos Soc 2022; 97:1231-1252. [PMID: 35137518 DOI: 10.1111/brv.12839] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 12/14/2022]
Abstract
Global movement patterns of migratory birds illustrate their fascinating physical and physiological abilities to cross continents and oceans. During their voyages, most birds land multiple times to make so-called 'stopovers'. Our current knowledge on the functions of stopover is mainly based on the proximate study of departure decisions. However, such studies are insufficient to gauge fully the ecological and evolutionary functions of stopover. If we study how a focal trait, e.g. changes in energy stores, affects the decision to depart from a stopover without considering the trait(s) that actually caused the bird to land, e.g. unfavourable environmental conditions for flight, we misinterpret the function of the stopover. It is thus important to realise and acknowledge that stopovers have many different functions, and that not every migrant has the same (set of) reasons to stop-over. Additionally, we may obtain contradictory results because the significance of different traits to a migrant is context dependent. For instance, late spring migrants may be more prone to risk-taking and depart from a stopover with lower energy stores than early spring migrants. Thus, we neglect that departure decisions are subject to selection to minimise immediate (mortality risk) and/or delayed (low future reproductive output) fitness costs. To alleviate these issues, we first define stopover as an interruption of migratory endurance flight to minimise immediate and/or delayed fitness costs. Second, we review all probable functions of stopover, which include accumulating energy, various forms of physiological recovery and avoiding adverse environmental conditions for flight, and list potential other functions that are less well studied, such as minimising predation, recovery from physical exhaustion and spatiotemporal adjustments to migration. Third, derived from these aspects, we argue for a paradigm shift in stopover ecology research. This includes focusing on why an individual interrupts its migratory flight, which is more likely to identify the individual-specific function(s) of the stopover correctly than departure-decision studies. Moreover, we highlight that the selective forces acting on stopover decisions are context dependent and are expected to differ between, e.g. K-/r-selected species, the sexes and migration strategies. For example, all else being equal, r-selected species (low survival rate, high reproductive rate) should have a stronger urge to continue the migratory endurance flight or resume migration from a stopover because the potential increase in immediate fitness costs suffered from a flight is offset by the expected higher reproductive success in the subsequent breeding season. Finally, we propose to focus less on proximate mechanisms controlling landing and departure decisions, and more on ultimate mechanisms to identify the selective forces shaping stopover decisions. Our ideas are not limited to birds but can be applied to any migratory species. Our revised definition of stopover and the proposed paradigm shift has the potential to stimulate a fruitful discussion towards a better evolutionary ecological understanding of the functions of stopover. Furthermore, identifying the functions of stopover will support targeted measures to conserve and restore the functionality of stopover sites threatened by anthropogenic environmental changes. This is especially important for long-distance migrants, which currently are in alarming decline.
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Affiliation(s)
- Heiko Schmaljohann
- Institute for Biology and Environmental Sciences (IBU), Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Straße 9-11, Oldenburg, 26129, Germany.,Institute of Avian Research, An der Vogelwarte 21, Wilhelmshaven, 26386, Germany
| | - Cas Eikenaar
- Institute of Avian Research, An der Vogelwarte 21, Wilhelmshaven, 26386, Germany
| | - Nir Sapir
- Department of Evolutionary and Environmental Biology and the Institute of Evolution, University of Haifa, 199 Aba Khoushy Ave, Haifa, 3498838, Israel
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Imlay TL, Mann HA, Taylor PD. Autumn migratory timing and pace are driven by breeding season carryover effects. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.05.003] [Citation(s) in RCA: 4] [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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Cohen EB, Horton KG, Marra PP, Clipp HL, Farnsworth A, Smolinsky JA, Sheldon D, Buler JJ. A place to land: spatiotemporal drivers of stopover habitat use by migrating birds. Ecol Lett 2020; 24:38-49. [PMID: 33026159 DOI: 10.1111/ele.13618] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/24/2020] [Accepted: 09/09/2020] [Indexed: 12/20/2022]
Abstract
Migrating birds require en route habitats to rest and refuel. Yet, habitat use has never been integrated with passage to understand the factors that determine where and when birds stopover during spring and autumn migration. Here, we introduce the stopover-to-passage ratio (SPR), the percentage of passage migrants that stop in an area, and use 8 years of data from 12 weather surveillance radars to estimate over 50% SPR during spring and autumn through the Gulf of Mexico and Atlantic coasts of the south-eastern US, the most prominent corridor for North America's migratory birds. During stopovers, birds concentrated close to the coast during spring and inland in forested landscapes during autumn, suggesting seasonal differences in habitat function and highlighting the vital role of stopover habitats in sustaining migratory communities. Beyond advancing understanding of migration ecology, SPR will facilitate conservation through identification of sites that are disproportionally selected for stopover by migrating birds.
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Affiliation(s)
- Emily B Cohen
- Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, 3001 Connecticut Ave NW, Washington, DC, 20008, USA
| | - Kyle G Horton
- Center of Avian Population Studies, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd, Ithaca, NY, 14850, USA
| | - Peter P Marra
- Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, 3001 Connecticut Ave NW, Washington, DC, 20008, USA
| | - Hannah L Clipp
- Department of Entomology and Wildlife Ecology, University of Delaware, 531 South College Ave, Newark, DE, 19716, USA
| | - Andrew Farnsworth
- Center of Avian Population Studies, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd, Ithaca, NY, 14850, USA
| | - Jaclyn A Smolinsky
- Department of Entomology and Wildlife Ecology, University of Delaware, 531 South College Ave, Newark, DE, 19716, USA
| | - Daniel Sheldon
- College of Information and Computer Sciences, University of Massachusetts, Amherst, MA, 01003, USA
| | - Jeffrey J Buler
- Department of Entomology and Wildlife Ecology, University of Delaware, 531 South College Ave, Newark, DE, 19716, USA
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DeSimone JG, Ramirez MG, Elowe CR, Griego MS, Breuner CW, Gerson AR. Developing a Stopover-CORT hypothesis: Corticosterone predicts body composition and refueling rate in Gray Catbirds during migratory stopover. Horm Behav 2020; 124:104776. [PMID: 32439349 DOI: 10.1016/j.yhbeh.2020.104776] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 11/21/2022]
Abstract
Migratory flight is energetically challenging, requiring alternating phases of fuel catabolism and fuel accumulation, accompanied by dramatic changes in body composition and behavior. Baseline corticosterone (CORT; the primary glucocorticoid in birds) is thought to underlie transitions between fuel catabolism during flight, fuel deposition during stopover, and the initiation of migratory flight. However, studies of CORT on stopover physiology and behavior remain disparate efforts, lacking the cohesion of a general hypothesis. Here we develop a Stopover-CORT hypothesis formalizing the relationships among CORT, body condition, and refueling rate in migratory birds. First we expect body mass to increase with triglycerides (TRIG) as birds refuel. Second, based on a synthesis of previous literature, we predict a U-shaped CORT curve over the course of stopover, postulating that elevated CORT at arrival is reactive, responding to poor body condition, while CORT elevation before departure is preparative, driving changes in behavior and body condition. We tested these predictions in Gray Catbirds (Dumetella carolinensis) following a trans-Gulf flight during spring migration. We found baseline CORT was negatively correlated with body condition and TRIG, corresponding with our predictions for arriving and refueling-but not departing-birds. It is possible catbirds undergo regional habitat translocations rather than complete the entire stopover phase at our study site. We propose the Stopover-CORT hypothesis as a useful predictive framework for future studies of the mechanistic basis of stopover physiology. By studying the regulation of stopover refueling and departure, we may better understand physiological limitations to overall migration rate and improve assessments of habitat quality for refueling birds.
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Affiliation(s)
- Joely G DeSimone
- Organismal Biology, Ecology, and Evolution, University of Montana, Missoula, MT 59812, USA.
| | | | - Cory R Elowe
- Organismic and Evolutionary Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Michael S Griego
- Organismic and Evolutionary Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Creagh W Breuner
- Organismal Biology, Ecology, and Evolution, University of Montana, Missoula, MT 59812, USA
| | - Alexander R Gerson
- Organismic and Evolutionary Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA; Department of Biology, University of Massachusetts Amherst, Amherst, MA 01003, USA
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Abstract
Bird migration is a long studied phenomenon that involves animals moving back and forth from wintering sites and to reproductive grounds. Several studies have focused on identifying the timing, physiology and evolution of migration, but a spatial approach to understand the migratory routes is still an open challenge. Geographic Information Systems (GIS) can provide the tools to explore such a complicated issue. Birds usually move from the wintering sites to spring breeding grounds in multiple flights, stopping at intermediate sites to rest and refuel, being unable to cover the distance in a single travel. The choice of stopover sites by birds depends not only on their ecological features but also on their position and visibility along main migratory flyways. In this work, we calculated the possible migratory routes that minimize the distance covered or the elevation gaps for birds crossing the Southern Alps, simulating the flight within a network connecting potential stopover sites and other relevant point of passage, using the shortest path computation. Subsequently, we performed a visibility analysis along the identified flyways to understand which stopover sites, belonging to the Natura2000 network, were visible for a bird in an area with complex morphology. Data available from ringing stations confirm the selection or avoidance of some stopover sites based on their en route visibility. The knowledge of bird flyways and stopover sites has implications for conservation as well as for planning, especially for wind farms or other infrastructures.
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de Zwaan DR, Wilson S, Gow EA, Martin K. Sex-Specific Spatiotemporal Variation and Carry-Over Effects in a Migratory Alpine Songbird. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00285] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
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9
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Gómez C, Guerrero SL, FitzGerald AM, Bayly NJ, Hobson KA, Cadena CD. Range‐wide populations of a long‐distance migratory songbird converge during stopover in the tropics. ECOL MONOGR 2019. [DOI: 10.1002/ecm.1349] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Camila Gómez
- Laboratorio de Biología Evolutiva de Vertebrados Departamento de Ciencias Biológicas Universidad de Los Andes Bogota 111711 Colombia
- SELVA: Investigación para la Conservación en el Neotrópico Bogota 111311 Colombia
| | - Sara L. Guerrero
- Laboratorio de Biología Evolutiva de Vertebrados Departamento de Ciencias Biológicas Universidad de Los Andes Bogota 111711 Colombia
| | - Alyssa M. FitzGerald
- Ecology and Evolutionary Biology State University of New York Albany New York 12222 USA
- University of California, Santa Cruz Santa Cruz California 95064 USA
- Fisheries Ecology Division, Southwest Fisheries Science Center National Marine Fisheries Institute, National Oceanic and Atmospheric Administration Santa Cruz California 95064 USA
| | - Nicholas J. Bayly
- SELVA: Investigación para la Conservación en el Neotrópico Bogota 111311 Colombia
| | | | - Carlos Daniel Cadena
- Laboratorio de Biología Evolutiva de Vertebrados Departamento de Ciencias Biológicas Universidad de Los Andes Bogota 111711 Colombia
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Ladin ZS, Van Nieuland S, Adalsteinsson SA, D’Amico V, Bowman JL, Buler JJ, Baetens JM, De Baets B, Shriver WG. Differential post-fledging habitat use of Nearctic-Neotropical migratory birds within an urbanized landscape. MOVEMENT ECOLOGY 2018; 6:17. [PMID: 30151198 PMCID: PMC6100711 DOI: 10.1186/s40462-018-0132-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Persistent declines in migratory songbird populations continue to motivate research exploring contributing factors to inform conservation efforts. Nearctic-Neotropical migratory species' population declines have been linked to habitat loss and reductions in habitat quality due to increasing urbanization in areas used throughout the annual cycle. Despite an increase in the number of studies on post-fledging ecology, generally characterized by the period between fledging and dispersal from natal areas or migration, contextual research linking post-fledging survival and habitat use to anthropogenic factors remains limited. METHODS Here, we examined habitat use of post-fledging habitat-generalist gray catbirds (Dumetella caroliniensis), and habitat-specialist wood thrushes (Hylocichla mustelina), up to 88 days after fledging within an urbanized landscape. These Neotropical migratory species share many life-history traits, exhibit differential degrees of habitat specialization, and co-occur in urbanized landscapes. Starting from daily movement data, we used time-integrated Brownian bridges to generate probability density functions of each species' probability of occurrence, and home range among 16 land cover classes including roads from the US Geological Survey National Land Cover Database for each species. RESULTS Habitat use differed between pre- and post-independence periods. After controlling for factors that influence habitat use (i.e., pre- or post-independence period, fate (whether individuals survived or not), and land cover class), we found that wood thrushes occupied home ranges containing six times more forest land cover than catbirds. In contrast, catbirds occupied home ranges containing twice the area of roads compared to wood thrushes. Wood thrushes had greater variance for area used (km2) among land cover classes within home ranges compared to catbirds. However, once fledglings achieved independence from parents, wood thrushes had lower variance associated with area used compared to catbirds. CONCLUSIONS Our findings support predictions that habitat-generalist gray catbirds spend more time in developed areas, less time in forest habitat, and use areas with more roads than the forest-specialist wood thrush. We found strong effects of pre- and post-independence periods on all of the response variables we tested. Species-specific habitat use patterns will likely be affected by projected increases in urbanization over the next several decades leading to further reductions in available forest habitat and increased road density, and will have important implications for the ecology and conservation of these birds.
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Affiliation(s)
- Zachary S. Ladin
- Department of Entomology and Wildlife Ecology, University of Delaware, Rm. 250 Townsend Hall, 531 South College Avenue, Newark, DE 19716 USA
| | - Steffie Van Nieuland
- Department of Data Analysis and Mathematical Modeling, Ghent University, Ghent, Belgium
| | | | - Vincent D’Amico
- US Forest Service, Northern Research Station, Newark, DE USA
| | - Jacob L. Bowman
- Department of Entomology and Wildlife Ecology, University of Delaware, Rm. 250 Townsend Hall, 531 South College Avenue, Newark, DE 19716 USA
| | - Jeffrey J. Buler
- Department of Entomology and Wildlife Ecology, University of Delaware, Rm. 250 Townsend Hall, 531 South College Avenue, Newark, DE 19716 USA
| | - Jan M. Baetens
- Department of Data Analysis and Mathematical Modeling, Ghent University, Ghent, Belgium
| | - Bernard De Baets
- Department of Data Analysis and Mathematical Modeling, Ghent University, Ghent, Belgium
| | - W. Gregory Shriver
- Department of Entomology and Wildlife Ecology, University of Delaware, Rm. 250 Townsend Hall, 531 South College Avenue, Newark, DE 19716 USA
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Paxton KL, Moore FR. Connecting the dots: Stopover strategies of an intercontinental migratory songbird in the context of the annual cycle. Ecol Evol 2017; 7:6716-6728. [PMID: 28904753 PMCID: PMC5587494 DOI: 10.1002/ece3.3227] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/12/2017] [Accepted: 06/13/2017] [Indexed: 01/17/2023] Open
Abstract
The phases of the annual cycle for migratory species are inextricably linked. Yet, less than five percent of ecological studies examine seasonal interactions. In this study, we utilized stable hydrogen isotopes to geographically link individual black‐and‐white warblers (Mniotilta varia) captured during spring migration with breeding destinations to understand a migrant's stopover strategy in the context of other phases of the annual cycle. We found that stopover strategy is not only a function of a bird's current energetic state, but also the distance remaining to breeding destination and a bird's time‐schedule, which has previously been linked to habitat conditions experienced in the preceding phase of the annual cycle. Birds in close proximity to their breeding destination accumulate additional energy reserves prior to arrival on the breeding grounds, as reflected by higher migratory condition upon arrival, higher refueling rates measured via blood plasma metabolites, and longer stopover durations compared to birds migrating to breeding destinations farther from the stopover site. However, late birds near their breeding destination were more likely to depart on the day of arrival (i.e., transients), and among birds that stopped over at the site, the average duration of stopover was almost half the time of early conspecifics, suggesting late birds are trying to catch‐up with the overall time‐schedule of migration for optimal arrival time on the breeding grounds. In contrast, birds with long distances remaining to breeding destinations were more likely to depart on the day of arrival and primarily used stopover to rest before quickly resuming migration, adopting similar strategies regardless of a bird's time‐schedule. Our study demonstrates that migrants adjust their en route strategies in relation to their time‐schedule and distance remaining to their breeding destination, highlighting that strategies of migration should be examined in the context of other phases of the annual cycle.
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Affiliation(s)
- Kristina L Paxton
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS USA.,Present address: Department of Biology University of Hawaii Hilo Hilo HI USA
| | - Frank R Moore
- Department of Biological Sciences University of Southern Mississippi Hattiesburg MS USA
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