Evidence map›Paper›PMID 36747277›Full record

ArticleMovement ecology2023

The oxidative balance and stopover departure decisions in a medium- and a long-distance migrant.

Cas Eikenaar, Alessia Ostolani, Vera Brust, Thiemo Karwinkel, Heiko Schmaljohann, Caroline Isaksson

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In one paragraph

Article in Movement ecology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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1citing papers in PubMed
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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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1 citing paper in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Cas EikenaarInstitute of Avian Research "Vogelwarte Helgoland", 26386, Wilhelmshaven, Germany. cas.eikenaar@ifv-vogelwarte.de.
Alessia OstolaniDepartment of Biology, University of Pisa, 56126, Pisa, Italy.
Vera BrustInstitute of Avian Research "Vogelwarte Helgoland", 26386, Wilhelmshaven, Germany.
Thiemo KarwinkelInstitute of Avian Research "Vogelwarte Helgoland", 26386, Wilhelmshaven, Germany.
Heiko SchmaljohannInstitute for Biology and Environmental Sciences (IBU), Carl von Ossietzky University of Oldenburg, 26129, Oldenburg, Germany.
Caroline IsakssonDepartment of Biology, Lund University, 223 62, Lund, Sweden.

Funding

Bundesamt für Naturschutz 3515822100 and 3151986140Deutsche Forschungsgemeinschaft EI 1048/4-1Deutsche Forschungsgemeinschaft SCHM 2647/3-1 and SCHM 2647/4-1
6 · The paper itself

Abstract

backgroundBirds have extremely elevated metabolic rates during migratory endurance flight and consequently can become physiologically exhausted. One feature of exhaustion is oxidative damage, which occurs when the antioxidant defense system is overwhelmed by the production of damaging reactive oxygen species (ROS). Migrating birds have been shown to decrease the amount of oxidative lipid damage during stopovers, relatively stationary periods in between migratory flights. It has therefore been argued that, in addition to accumulating fuel, one of the functions of stopover is to restore the oxidative balance. If this is so, we would expect that migrating birds are unlikely to resume migration from stopover when they still have high amounts of lipid damage.

methodsTo test this hypothesis, we measured parameters of the oxidative balance and related these to stopover departure decisions of song thrushes (Turdus philomelos) and northern wheatears (Oenanthe oenanthe), a medium- and long-distance songbird migrant, respectively. We measured malondialdehyde (MDA) concentration, a biomarker for oxidative lipid damage, and total non-enzymatic antioxidant capacity (AOX), an overall biomarker of protection against ROS. Stopover departure decisions were determined using a fully automated telemetry system set-up on our small island study site.

resultsThe decision to resume migration was not related with MDA concentration in either study species, also not when this was corrected for circulating fatty acid concentrations. Similarly, AOX did not affect this decision, also not when corrected for uric-acid concentration. The time within the night when birds departed also was not affected by MDA concentration or AOX. However, confirming earlier observations, we found that in both species, fat individuals were more likely to depart than lean individuals, and fat northern wheatears departed earlier within the night than lean conspecifics. Northern wheatears additionally departed earlier in spring with more southerly winds.

conclusionsWe found no support for the idea that stopovers departure decisions are influenced by parameters of the oxidative balance. We discuss possible reasons for this unexpected finding.

Indexed as

DepartureMigrationPhysiologyRadio-telemetryStopover

Identifiers

PMID36747277
PMCPMC9903453

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