Understanding the ecological and evolutionary function of stopover in migrating birds

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2022, Volume and Issue: 97(4), P. 1231 - 1252

Published: Feb. 8, 2022

ABSTRACT Global movement patterns of migratory birds illustrate their fascinating physical and physiological abilities to cross continents oceans. During voyages, most land multiple times make so‐called ‘stopovers’. Our current knowledge on the functions stopover is mainly based proximate study departure decisions. However, such studies are insufficient gauge fully ecological evolutionary stopover. If we how a focal trait, e.g. changes in energy stores, affects decision depart from without considering trait(s) that actually caused bird land, unfavourable environmental conditions for flight, misinterpret function It thus important realise acknowledge stopovers have many different functions, not every migrant has same (set of) reasons stop‐over. Additionally, may obtain contradictory results because significance traits context dependent. For instance, late spring migrants be more prone risk‐taking with lower stores than early migrants. Thus, neglect decisions subject selection minimise immediate (mortality risk) and/or delayed (low future reproductive output) fitness costs. To alleviate these issues, first define as an interruption endurance flight costs . Second, review all probable stopover, which include accumulating energy, various forms recovery avoiding adverse list potential other less well studied, minimising predation, exhaustion spatiotemporal adjustments migration. Third, derived aspects, argue paradigm shift ecology research. This includes focusing why individual interrupts its likely identify individual‐specific function(s) correctly departure‐decision studies. Moreover, highlight selective forces acting dependent expected differ between, K −/ r ‐selected species, sexes migration strategies. example, else being equal, species survival rate, high rate) should stronger urge continue or resume increase suffered offset by higher success subsequent breeding season. Finally, propose focus mechanisms controlling landing decisions, ultimate shaping ideas limited but can applied any species. revised definition proposed stimulate fruitful discussion towards better understanding Furthermore, identifying will support targeted measures conserve restore functionality sites threatened anthropogenic changes. especially long‐distance migrants, currently alarming decline.

Language: Английский

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Proximate mechanisms affecting seasonal differences in migration speed of avian species

Scientific Reports, Journal Year: 2018, Volume and Issue: 8(1)

Published: March 1, 2018

Faster migration in spring than autumn seems to be a common pattern birds. This has been ultimately explained by seasonally different selection pressures. Variation speed is proximately caused adjusting travel (distance covered during flight) and/or stopover duration (times when birds rest and refuel). Yet, it remains unclear whether individual seasonal differences match the what precise role of proximate, behavioural mechanisms for is. By reviewing 64 studies 401 tracks, I show that waders, gulls, swifts, songbirds speeds were significantly higher spring, while opposite was case waterfowl owls. Thus, ultimate selecting faster might not consistently act across bird groups. Breeding latitude, strategy, distance, flight style, body mass, sex did explain speed. The ratio between total 257 tracks negatively affected same individuals comparative analysis accounting shared ancestry. Seasonal variation appears thus main biological mechanism regulating

Language: Английский

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Stopover departure decisions in songbirds: do long-distance migrants depart earlier and more independently of weather conditions than medium-distance migrants?

Movement Ecology, Journal Year: 2020, Volume and Issue: 8(1)

Published: Feb. 7, 2020

Songbirds following distinct migration strategies (e.g. long- vs. short- to medium-distance migrants) often differ in their speed of during autumn and, thus, are assumed face different time constraints. During migration, most songbird species alternate migratory flights with stopover periods. Many them restrict these the night, i.e., they nocturnal migrants. At stopover, migrants need select a specific night (night-to-night decision) and (within-night resume migration. These departure decisions, which largely determine jointly affected by set intrinsic extrinsic factors, cues. Here we aim assess whether factors magnitude respective effects on decisions differs between nocturnally migrating species, depending strategy associated constraints.We radio-tracked Northern Wheatears (Oenanthe oenanthe; long-distance migrant), European robins (Erithacus rubecula) Common Blackbirds (Turdus merula; both analysed night-to-night within-night timing relation factors.Species generally differed temporal scales, shortest stopovers earliest departures migrant. Some such as day year, fuel load, cloud cover crosswind, had consistent all three species. However, tailwind assistance, change atmospheric pressure air temperature decisions. Whereas were either or one migrants, not found migrant.Our results suggest that general songbirds is species-specific Further, imply assessment usage weather conditions, cues adjusted based this strategy, being least selective at departure. Other however, seem be used independent strategy.

Language: Английский

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The physiology of movement

Movement Ecology, Journal Year: 2020, Volume and Issue: 8(1)

Published: Feb. 4, 2020

Abstract Movement, from foraging to migration, is known be under the influence of environment. The translation environmental cues individual movement decision making determined by an individual’s internal state and anticipated balance costs benefits. General body condition, metabolic hormonal physiology mechanistically underpin this state. These physiological determinants are tightly, often genetically linked with each other hence central a mechanistic understanding movement. We here synthesise available evidence drivers signatures review (1) how as measured in its most coarse way condition correlates decisions during foraging, migration dispersal, (2) changes underlie these strategies (3) can molecular pathways. reveale that high facilitates efficiency routine dispersal migration. Dispersal is, however, some cases stimulated decreased condition. Many biotic abiotic stressors induce initiate cascade vertebrates through production stress hormones. Movement therefore associated hormone levels but also insects, interaction factors related or social underlying mechanisms currently studied few model species, show –in congruence our insights on role condition- energy metabolism glycolysis, coupling timing processes Molecular into basis remain, highly refractory. finalise critical reflection importance feedbacks for better effects ecological dynamics at all biological organization.

Language: Английский

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Beyond refueling: Investigating the diversity of functions of migratory stopover events

Ornithological Applications, Journal Year: 2021, Volume and Issue: 123(1)

Published: Feb. 1, 2021

Abstract Stopovers comprise a significant proportion of the time that many birds spend migrating, and researchers have long relied on these events to define classify broader migratory strategies. Analyses stopovers often assume individuals stop primarily or exclusively in order replenish energy stores, but other non-fueling behaviors also been described during stopover can influence incidence duration. Here, we discuss growing demand for understanding restoring inherent behavioral complexity events. We begin by describing how light-weight tracking technologies allow follow along their entire journeys, capturing controvert traditional stop–refuel–resume paradigm. then 5 well-identified behaviors—recovering, sleeping, waiting, information gathering, social interactions—and examine including alter interpretations individual movement paths. Finally, outline emerging directions identifying look larger implications population management site conservation flyways.

Language: Английский

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Not just fuel: energy stores are correlated with immune function and oxidative damage in a long-distance migrant

Current Zoology, Journal Year: 2019, Volume and Issue: 66(1), P. 21 - 28

Published: March 7, 2019

Abstract In many animals, catabolic and anabolic periods are temporally separated. Migratory birds alternate energy expenditure during flight with accumulation stopover. The size of the stores at stopover affects decision to resume migration thus temporal organization migration. We now provide data suggesting that it is not only per se may influence scheduling, but also physiological consequences flying. two subspecies northern wheatear Oenanthe oenanthe, a long-distance migrant, estimated autumn were positively related both constitutive innate acquired immune function, negatively oxidative damage lipids. other words, migrants’ condition was associated their energetic condition. Although time spent before sampling have contributed this relationship, our results suggest migrants trade-off depletion incurring costs. This will affect decisions when start terminate migratory flight. costs help explaining why often arrive depart from sites larger than expected. propose studies on role as drivers (avian) need consider condition, such immunological states.

Language: Английский

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Immune function and blood parasite infections impact stopover ecology in passerine birds

Oecologia, Journal Year: 2018, Volume and Issue: 188(4), P. 1011 - 1024

Published: Nov. 1, 2018

Stopovers play a crucial role for the success of migrating animals and are key to optimal migration theory. Variation in refuelling rates, stopover duration departure decisions among individuals has been related several external factors. The physiological mechanisms shaping ecology are, however, less well understood. Here, we explore how immune function blood parasite infections relate aspects behaviour autumn short- long-distance songbirds. We sampled six species used an automated radio-telemetry system area subsequently quantify duration, 'bush-level' activity patterns (~ 0.1–30 m), landscape movements 30–6000 direction time. show that complement activity, acute phase protein haptoglobin were prolonged duration. Complement (i.e., lysis) total immunoglobulins negatively correlated with bush-level patterns. differences partly depended on whether birds or short-distance migrants. Birds infected avian malaria-like parasites showed longer during than uninfected individuals, double departed more 2.5 h later after sunset/sunrise suggesting shorter flight bouts. conclude variation baseline infection status affects helps explain individual behaviour. These affect overall speed, thus can have significant impact induce carry-over effects other annual-cycle stages. Immune should, therefore, be considered as important factors when applying

Language: Английский

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The start of migration correlates with arrival timing, and the total speed of migration increases with migration distance in migratory songbirds: a cross-continental analysis

Movement Ecology, Journal Year: 2019, Volume and Issue: 7(1)

Published: Aug. 11, 2019

Anthropogenic changes in the climate and environment have globally affected ecological processes such that spatiotemporal occurrence of main annual cycle events (i.e., breeding, wintering, moulting, migration) has shifted migratory birds. Variation arrival timing at destinations can be proximately caused by an altered start migration, total migration distance, and/or speed migration. Quantifying relative contributions these causes is important because this will indicate mechanisms whereby birds could potentially adjust their response to global change. However, we relatively little quantitative information about how each factors contributes variation timing. My aims are estimate correlated with distance may change body mass a comprehensive analysis including multiple species.For purpose, I considered individual tracks covering complete migrations from species distinguished between within- between-species effects.Assuming effects quantified under approach agree acting level, starting one day later or increasing 1000 km would result 0.4-0.8 days 2-5 days, respectively. The generality which within suggests general biological mechanism regulating timing, rather than distance. was positively but not bird's mass.As endogenously controlled hatching date, directional selection probably act on existing within-species/within-population alter This factor importance for suggest species/populations there sufficient transgenerational affect corresponding present advantage over others coping anthropogenic-induced changes.

Language: Английский

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Avian Use of Agricultural Areas as Migration Stopover Sites: A Review of Crop Management Practices and Ecological Correlates

Frontiers in Ecology and Evolution, Journal Year: 2021, Volume and Issue: 9

Published: May 14, 2021

An estimated 17% of migratory bird species are threatened or near with extinction. This represents an enormous potential loss biodiversity and cost to human societies due the economic benefits that birds provide through ecosystem services ecotourism. Conservation presents many unique challenges, as these rely on multiple geographically distinct habitats, including breeding grounds, non-breeding stopover sites during migration. In particular, habitats seldom studied relative despite their importance refueling stations for birds. this study, we summarize current research use temporary primary crops by migration assess characteristics agricultural practices most often associated cropland habitat. First, conducted a systematic review literature document effects various farming crop types have abundance diversity using areas stopovers. Second, analyzed ecological correlates in Northern Hemisphere predict which may while migrating. We ran GLMM test whether diet, diet breadth, habitat, habitat realm predicted areas. Our suggests particular (principally rice, corn, sunflower), well result higher non-cultivated plant diversity, encourage migrating found is used can utilize large breadth preferences similar structure

Language: Английский

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Nocturnal departure timing in songbirds facing distinct migratory challenges

Journal of Animal Ecology, Journal Year: 2018, Volume and Issue: 87(4), P. 1102 - 1115

Published: March 5, 2018

Abstract Most migratory songbirds travel between their breeding areas and wintering grounds through a series of nocturnal flights. The timing departures defines the potential flight duration thus distance covered during night. Yet, show substantial variation in departure timing. With this study, we aim to assess whether respective challenges migration route, namely its nature, help explain variation. At stopover site, caught Northern Wheatears ( Oenanthe oenanthe ) two subspecies that differ nature onward route spring, but not autumn. We determined start restlessness short‐term captivity, radiotracked after release both seasons. started earlier when facing long remaining an extended sea barrier spring. Individual directions generally affected with early being directed towards destination. In pattern was predominantly found birds carrying relatively large fuel stores, absent lean birds. same time, short no strongly reacted stores by behaviour (migratory timing), whereas reaction barrier. These results suggest basic diel schedule birds’ activity is adapted route. Further, they adjust behavioural response, behaviour, relation impending challenges. This step understanding adjustments songbirds. it emphasizes importance interpreting ecological context.

Language: Английский

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