currently housed at the University of Rostock in Rostock, Germany. Image Credit:
University of Rostock.
Spring is fast approaching, and with its arrival come many seasonal visitors to New York: Birds migrating from Central and South America arrive in vast numbers to breed and raise their chicks. They make the long journey because the days in the northern latitudes are becoming seasonally longer than in the tropics and there is a greater abundance of food in the form of emerging insects and flowers. They also avoid breeding in the high heat and humidity of the more southerly latitudes, which would present serious challenges to the success of their eggs and chicks. When the weather in the northern latitudes begin to turn cold, the birds return to their territories in the tropics.
The first concrete evidence that birds migrate from continent to continent came in 1822, when a White Stork (Ciconia ciconia) landed near the northern German village of Klütz with a 30-inch spear protruding through its neck. The spear was determined to be made from African wood, meaning this stork must have traveled between the continents. At least 24 subsequent storks sporting an African spear or piece of spear, now referred to as pfeilstorche, or arrow-storks, have been identified in Europe.
While Indigenous peoples in Alaska, such as the Athabascans, knew long ago that geese migrated south over the ocean, they didn’t know where the birds were headed. But that didn’t stop people from speculating about where the birds were going. The Greek philosopher Aristotle suggested that many of the disappearing birds simply hibernated in nooks and crannies during the winter. Others suggested that they metamorphosed into other types of birds, or even rodents, that were better able to cope with wintry weather. In the mid-17th century, the English naturalist Francis Willughby suggested (accurately but without evidence) that many European birds most likely wintered in Africa, but that didn’t stop Harvard professor Charles Morton from writing in the 1680s that the most logical location for birds to migrate to and from was…the moon!
Today, we track birds using armies of birdwatchers and modern technology, and we take these two-way migrations for granted. But for thousands of years, no one really knew where many of the birds we see in the spring and summer went in the fall and winter.