Albatross spend most of their lives in flight. They forage in the open ocean, where food may be separated by many miles, and they head for islands only to breed. They have been documented making around-the-world trips in just 46 days (take that, Jules Verne!) and flying for weeks at an average speed of 950 km per day (Croxall et al. 2005). That’s 40 km per hour, so you could beat them in a car (if you could stay awake that long), but still!
How can an animal spend so much time in such fast flight? How do albatross not waste away and die from the sheer energetic effort?
They have some tricks. One is physical: imagine holding your arms outstretched for weeks—it would be awful, right? Birds are built for outstretched forelimbs better than we are, but even so, the strain of simply holding out their wings for that long should be a problem for albatross. The solution? They have a “shoulder lock,” a rigid tendon that acts as a strut to passively prop up their wings. They also have a lot of slow fibers in their wing muscles, meaning that those muscles are good at sustained activity (Meyers & Stakebake 2005).
Their best trick, though, is that they have figured out how to fly without—theoretically, at least—expending any energy at all. They almost never flap their wings; like any bird with long, narrow wings, they are best as gliding flight, not flapping. (This video shows the running start albatross need to take off, but makes them look much more competent than they often are; albatross sometimes need several attempts to get off the ground.)
Hawks and vultures are great gliders too, but they get to use the rising hot air of thermals to keep them aloft. There aren’t many thermals on the open ocean, so albatross use a strategy called “dynamic soaring,” which lets them glide potentially endlessly while theoretically expending no energy.
Dynamic soaring takes advantage of the fact that wind near the water’s surface is slowed down by friction with the water, and wind a little higher than that is slowed down by the slower wind below it, and so on; so there is an increase in wind speed as you move higher from the water. This is represented by the black arrows in the diagram below: longer arrows mean faster wind.
At point (1) on the diagram, the albatross is near the water’s surface and flying towards the wind and upward. It’s losing speed, since it’s flying into the wind. However, once it gets high enough that the wind is quite fast (2), it turns around and goes with the wind as far as the energy of that fast wind can take it, gradually falling back towards the water (3). When it gets low again, it turns toward the wind, and the cycle repeats.
The albatross loses speed when it goes up into the wind, but it gains even more speed than it lost when it turns and glides with the wind – just enough extra gain to compensate for drag, friction with the air that slows down all flying things. That extra speed is possible because the albatross mostly goes toward the wind when it’s low, where the wind is slow, and mostly goes with the wind when it’s high and the wind is fast (Sachs et al. 2012).
In addition to dynamic soaring, albatross may also use variations in the wind around waves to get extra little bursts of energy (Pennycuick 2002). Albatross in flight with favorable winds use up “little more energy than birds resting on land” (Weimerskirch et al. 2000).
Flying out in the open ocean can be challenging. In March 2003, a Gray-headed Albatross fitted with a GSP locator flew into an Antarctic storm. For nine hours, thanks to high tailwinds from the storm, it flew at 127 km/hr (79 mph)—and continued to capture prey at the same rate it would have under normal weather conditions (Catry et al. 2004). Albatross may do funny dances and look less than dignified when they are young, but they perform amazing feats of flight as a matter of daily life.
Edit: Maggie wondered where the albatross’ feet were; here’s proof that they do still have feet when flying:
Catry P et al. 2004. Sustained fast travel by a Gray-headed Albatross (Thalassarche chrysostoma) riding an Antarctic Storm. The Auk 121(4):1208-1213.
Croxall JP et al. 2005. Global circumnavigations: tracking year-round ranges of nonbreeding albatrosses. Science 307:249-250.
Meyers RA, Stakebake EF. 2005. Anatomy and histochemistry of spread-wing posture in birds. 3. Immunohistochemistry of flight muscles and the “shoulder lock” in albatrosses. Journal of Morphology 263:12-29.
Pennycuick CJ. 2002. Gust soaring as a basis for the flight of petrels and albatrosses (Procellariiformes). Avian Science 2(1):1-12.
Sachs G et al. 2012. Flying at no mechanical energy cost: disclosing the secret of wandering albatrosses. PLoS ONE 7(9): e41449. doi:10.1371/journal.pone.0041449
Weimerskirch H et al. 2000. Fast and fuel efficient? Optimal use of wind by flying albatrosses. Proc. Roy. Soc. B 267(1869-1874).