Oceanic seabirds chase tropical cyclones.

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, but cyclones can also enhance pelagic primary and secondary production. However, cyclone impacts on open ocean marine life remain poorly understood.

Observations and models of across-wind flight speed of the wandering albatross.

Wandering albatrosses exploit wind shear by dynamic soaring (DS), enabling rapid, efficient, long-range flight. We compared the ability of a theoretical nonlinear DS model and a linear empirical model to explain the observed variation of mean across-wind airspeeds of GPS-tracked wandering albatrosses. Assuming a flight trajectory of linked, 137° turns, a DS cycle of 10 s and a cruise airspeed of 16 m s, the theoretical model predicted that the minimum wind speed necessary to support DS is greater than 3 m s.

Flight speed and performance of the wandering albatross with respect to wind.

Background: Albatrosses and other large seabirds use dynamic soaring to gain sufficient energy from the wind to travel large distances rapidly and with little apparent effort. The recent development of miniature bird-borne tracking devices now makes it possible to explore the physical and biological implications of this means of locomotion in detail. Here we use GPS tracking and concurrent reanalyzed wind speed data to model the flight performance of wandering albatrosses soaring over the Southern Ocean.