A Fly-by-Night Operation

NightSkyBirds

Many birds make their seasonal departures and returns when people are least likely to see them—at night. No wonder folks long ago believed that these creatures migrated to the moon. Little, though, did they suspect the stars’ role in such journeys.

Navigating by the Stars

Before developing sophisticated GPS devices and even the magnetic compass, we humans relied on the constellations for guidance during nightly travels. So what if birds happened to use the stars in a similar manner? Sure, it may sound a bit farfetched at first. However, studies from over the past few decades indicate that for many species this is likely the case. In fact, certain birds depend on constellations as guideposts, so much so that researchers have discovered that heavy clouds can obstruct their view and, in turn, lead them astray, requiring the creatures to later correct their flights.

Like these birds, our ancestors, too, used astronomical formations as navigational aids. By identifying clusters of stars into constellations, earlier explorers were capable of making extensive expeditions over land and voyages over sea, long before the inventions of satellite technology and electronic communications. Connecting the night’s starry dots into linear forms was critical for orienting purposes. Some folks today still use the stars in this way.

An Interstellar Assembly of Fowl

The human practice of studying the stars has resulted in some interesting constellations, as societies easily found inspiration in their own myths as well as in the creatures around them. Among the most familiar bird-related constellations in the West are the Eagle (Aquila), Dove (Columba), Raven (Corvus), Swan (Cygnus), Crane (Grus), Peacock (Pavo), and Toucan (Tucana) (1, 2). Stargazers in other places, of course, generated different names for the same combinations. For instance, the Arabian equivalent to the constellation Lyra is sometimes referred to as the Vulture (3). In that same constellation, some aborigine people of southeast Australia see instead a Mallee-fowl (4). Different constellations also appear only to specific societies (not unlike a kind of Rorschach test), as in the case of a large Emu constellation recognized as well by Australian aborigines (5).

The Mi’kmaq people of eastern Canada associated certain stars with birds. In their folklore, the constellation commonly referred to as the “Big Dipper” or Ursa Major is related as seven birds hunting a bear. The birds, all represented by individual stars, include a Chickadee, Blue Jay, and Pigeon, among others. They attempt to trail the ursine from the spring until fall, but only the Robin is at last able to kill the great bear. Interestingly, the Mi’kmaq’s astronomical interpretation operates as well as a just-so story, in that it seeks to explain why the robin has a red breast and why fall foliage turns red (both, according to the tale, due to the bear’s massive bloodshed) (6).

Starry Nights, Starry Flights

As mentioned earlier, ornithologists began learning decades ago that birds can use the constellations for navigational purposes. In the mid-20th century, Franz Sauer was the first to discover that such a thing was even possible. He ran numerous experiments on European warblers which led him to conclude that the birds have the ability to orient themselves directionally by the stars during autumnal migration periods. Another prominent researcher in this field, Stephen Emlen has worked extensively on indigo buntings (7, 8). He has stated, “Numerous species have been examined, and it appears that the ability to orient by the stars is widespread among birds that migrate at night” (9).

Interestingly enough, researchers use the full moon as a lit backdrop for tracking birds during these nocturnal migrations. As a bird flies over the moon, its silhouette is recorded via a photographic telescope. One such facility that routinely conducts such studies is Indiana’s Chipper Woods Bird Observatory (10). Another is New Hampshire’s Squam Lakes Natural Science Center, responsible for this YouTube video of several passing birds over a full moon. Of course, with spring on the way, more and more birds will be making such nocturnal migrations.

Sources:

  1. Cornelius, G. The Starlore Handbook: An Essential Guide to the Night Sky. San Francisco: Chronicle Books, 1997.
  2. “Constellation Names”, Constellation Guide: http://www.constellation-guide.com/constellation-names/
  3. Heck, C., Cordonnier, R. The Grand Medieval Bestiary: Animals in Illuminated Manuscripts. New York: Abbeville Press Publishers, 2012. p. 69.
  4. Norris, R. “Australian Aboriginal Astronomy: Calendars”, Australia Telescope National Facility: http://www.atnf.csiro.au/research/AboriginalAstronomy/Examples/calendar.htm.
  5. Norris, R. “Australian Aboriginal Astronomy: The Emu in the Sky”, Australia Telescope National Facility: http://www.atnf.csiro.au/research/AboriginalAstronomy/Examples/emu.htm.
  6. Dempsey, F. “Aboriginal Canadian Sky Lore of the Big Dipper”, Journal of the Royal Astronomical Society of Canada, Vol. 102, No. 2, April 2008. pp. 59-61.
  7. Moon Watching: Studying Birds that Migrate at Night”, Chipper Woods Bird Observatory, Indianapolis, IN: http://www.wbu.com/chipperwoods/photos/moon.htm.
  8. Emlen, S.T. “The Stellar-Orientation System of a Migratory Bird”, p. 3: http://courses2.cit.cornell.edu/bionb221/WIM/readings/Emlen%20%281975%29%20-%20The%20stellar-orientation%20system%20of%20a%20migratory%20bird.pdf. (Also appeared in Scientific American. Vol. 233, August 1975. pp. 102-111.)
  9. Emlen, S.T.
  10. Moon Watching: Studying Birds that Migrate at Night”, Chipper Woods Bird Observatory, Indianapolis, IN.
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