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Optimal Bird Migration: The Relative Importance of Time, Energy, and Safety
“Optimization is the process of minimizing costs or maximizing benefits, or obtaining the best possible compromise between the two,” (R. McNeill Alexander 1982).
Differences in the climatic debts of birds and butterflies at a continental scale
Climate changes have profound effects on the distribution of numerous plant and animal species(1-3). However, whether and how different taxonomic groups are able to track climate changes at large
Fuel deposition rates in migrating birds: Causes, constraints and consequences.
Most, if not all, migrants deposit fuel before they fly. Some migrants can more than double their mass from fuelling (Piersma and Gill 1998), whereas others, like the white stork, Ciconia cconia, put
Fuel use and metabolic response to endurance exercise: a wind tunnel study of a long-distance migrant shorebird.
The relationships between energy expenditure, body mass loss and metabolic pattern suggest that a higher individual energy expenditure entails a higher rate of catabolism of both lipids and protein and not a shift in fuel substrate.
Carrying large fuel loads during sustained bird flight is cheaper than expected
The most likely explanation is that the efficiency with which metabolic power input is converted into mechanical output by the flight muscles increases with fuel load, which will influence current models of bird flight and bird migration.
Maximum fat deposition rates in migrating birds
Large birds are generally more efficient flyers than smaller birds and can therefore partly compensate for their lower maximum fat deposition rates, and maximum speed of migration is predicted to be proportional to M-014, where M = lean body mass.
Timing of spring migration in birds: long-term trends, North Atlantic Oscillation and the significance of different migration routes
Long-distance migrants wintering south and south-east of the breeding grounds showed some of the strongest changes in long-term trends (passing progressively earlier) at Ottenby, and for some of these species passage time varied negatively with NAO.
The Energetic Cost of Feather Synthesis Is Proportional to Basal Metabolic Rate
It was concluded that neither diet nor latitudinal constraints alone could explain the differences found between species, and the tight association of Cf and BMRm between species suggests that feather production costs include more than the costs for keratin synthesis: they mainly consist of costs of maintaining tissues necessary for feather production.
Basal metabolic rate in migratory waders: intra-individual, intraspecific, interspecific and seasonal variation
The data contradict the idea that BMR is high during migration as an adaptation to generally high levels of energy expenditure and indicate that non-fat tissues, with a high metabolic activity, are involved in the mass changes during migratory stopover.
Optimal departure decisions of songbirds from an experimental stopover site and the significance of weather
Recent models have worked with the assumption that birds try to minimize either time, energy or predation risk during migration, or some combination of these. The few empirical studies available have