Migrating songbirds on stopover prepare for, and recover from, oxidative challenges posed by long‐distance flight

Ecology and Evolution

Megan M. Skrip⁴  Ulf Bauchinger⁵  Wolfgang Goymann¹  Leonida Fusani²  Massimiliano Cardinale³  Rebecca R. Alan⁴ 

[1] Max-Planck-Institut für Ornithologie, Abteilung für Verhaltensneurobiolgie, Seewiesen, Germany;ORCID:orcid.org/0000-0001-8900-796X;Department of Aquatic Resources, Marine Research Institute, Swedish University of Agricultural Sciences, Lysekil, Sweden;Department of Natural Resources Science, University of Rhode Island, Kingston, Rhode Island;Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland

关键词: Antioxidant capacity;    condition dependency;    ecological barriers;    lipid oxidation;    long‐distance flight;    migration strategy;   

DOI  :  10.1002/ece3.1601

来源: Wiley

【 摘 要 】

Abstract

Managing oxidative stress is an important physiological function for all aerobic organisms, particularly during periods of prolonged high metabolic activity, such as long-distance migration across ecological barriers. However, no previous study has investigated the oxidative status of birds at different stages of migration and whether that oxidative status depends on the condition of the birds. In this study, we compared (1) energy stores and circulating oxidative status measures in (a) two species of Neotropical migrants with differing migration strategies that were sampled at an autumn stopover site before an ecological barrier; and (b) a species of trans-Saharan migrant sampled at a spring stopover site after crossing an ecological barrier; and (2) circulating oxidative measures and indicators of fat metabolism in a trans-Saharan migrant after stopovers of varying duration (0–8 nights), based on recapture records. We found fat stores to be positively correlated with circulating antioxidant capacity in Blackpoll Warblers and Red-eyed Vireos preparing for fall migration on Block Island, USA, but uncorrelated in Garden Warblers on the island of Ponza, Italy, after a spring crossing of the Sahara Desert and Mediterranean Sea. In all circumstances, fat stores were positively correlated with circulating lipid oxidation levels. Among Garden Warblers on the island of Ponza, fat anabolism increased with stopover duration while oxidative damage levels decreased. Our study provides evidence that birds build antioxidant capacity as they build fat stores at stopover sites before long flights, but does not support the idea that antioxidant stores remain elevated in birds with high fuel levels after an ecological barrier. Our results further suggest that lipid oxidation may be an inescapable hazard of using fats as the primary fuel for flight. Yet, we also show that birds on stopover are capable of recovering from the oxidative damage they have accrued during migration, as lipid oxidation levels decrease with time on stopover. Thus, the physiological strategy of migrating songbirds may be to build prophylactic antioxidant capacity in concert with fuel stores at stopover sites before a long-distance flight, and then repair oxidative damage while refueling at stopover sites after long-distance flight.

【 授权许可】

CC BY   
© 2015 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.