Dataset Information

Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist.

ABSTRACT: External factors such as geography and weather strongly affect bird migration influencing daily travel schedules and flight speeds. For strictly thermal-soaring migrants, weather explains most seasonal and regional differences in speed. Flight generalists, which alternate between soaring and flapping flight, are expected to be less dependent on weather, and daily travel schedules are likely to be strongly influenced by geography and internal factors such as sex. We GPS-tracked the migration of 70 lesser kestrels (Falco naumanni) to estimate the relative importance of external factors (wind, geography), internal factors (sex) and season, and the extent to which they explain variation in travel speed, distance, and duration. Our results show that geography and tailwind are important factors in explaining variation in daily travel schedules and speeds. We found that wind explained most of the seasonal differences in travel speed. In both seasons, lesser kestrels sprinted across ecological barriers and frequently migrated during the day and night. Conversely, they travelled at a slower pace and mainly during the day over non-barriers. Our results highlighted that external factors far outweighed internal factors and season in explaining variation in migratory behaviour of a flight generalist, despite its ability to switch between flight modes.

SUBMITTER: Lopez-Ricaurte L

PROVIDER: S-EPMC8187636 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist.

Lopez-Ricaurte Lina L Vansteelant Wouter M G WMG Hernández-Pliego Jesús J García-Silveira Daniel D Bermejo-Bermejo Ana A Casado Susana S Cecere Jacopo G JG de la Puente Javier J Garcés-Toledano Fernando F Martínez-Dalmau Juan J Ortega Alfredo A Rodríguez-Moreno Beatriz B Rubolini Diego D Sarà Maurizio M Bustamante Javier J

Scientific reports 20210608 1

External factors such as geography and weather strongly affect bird migration influencing daily travel schedules and flight speeds. For strictly thermal-soaring migrants, weather explains most seasonal and regional differences in speed. Flight generalists, which alternate between soaring and flapping flight, are expected to be less dependent on weather, and daily travel schedules are likely to be strongly influenced by geography and internal factors such as sex. We GPS-tracked the migration of 7 ...[more]

PMID: 34103580

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Dataset Information

Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist.

Publications

Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist.

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