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Abstract(s)
In late summer and autumn, the passage of intense tropical cyclones can profoundly perturb oceanic and
coastal ecosystems. Direct negative effects on individuals and marine communities can be dramatic, especially in the coastal zone,1–4 but cyclones can also enhance pelagic primary and secondary production.5–9
However, cyclone impacts on open ocean marine life remain poorly understood. Here, we investigate their
effects on the foraging movements of a wide-ranging higher predator, the Desertas petrel (Pterodroma deserta), in the mid-latitude North Atlantic during hurricane season. Contrary to previously studied pelagic seabirds in tropical and mid-latitude regions,10,11 Desertas petrels did not avoid cyclones by altering course, nor
did they seek calmer conditions within the cyclone eye. Approximately one-third of petrels tracked from their
breeding colony interacted with approaching cyclones. Upon encountering strong winds, the birds reduced
ground speed, likely by spending less time in flight. A quarter of birds followed cyclone wakes for days and
over thousands of kilometers, a behavior documented here for the first time. Within these wakes, tailwind
support was higher than along alternative routes. Furthermore, at the mesoscale (hours–weeks and hundreds
of kilometers), sea surface temperature dropped and surface chlorophyll sharply increased, suggesting
direct effects on ocean stratification, primary production, and therefore presumably prey abundance and
accessibility for surface-feeding petrels. We therefore hypothesize that cyclone wakes provide both predictably favorable wind conditions and foraging opportunities. As such, cyclones may have positive net effects
on the demography of many mid-latitude pelagic seabirds and, likely, other marine top-predators.
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Citation
Ventura, F., Sander, N., Catry, P., Wakefield, E., De Pascalis, F., Richardson, P. L., Granadeiro, J. P., Silva, M. C., & Ummenhofer, C. C. (2024). Oceanic seabirds chase tropical cyclones. Current Biology, 34(14), 3279–3285. https://doi.org/10.1016/j.cub.2024.06.022
Publisher
Cell Press