It’s a comment often heard from backyard birders:
“The hummingbirds left early this year, so that must mean a hard winter ahead.”
That’s a myth, says Tennessee Wildlife Resources Agency ornithologist Scott Somershoe.
“I get calls about such things every Dan Cook year,” he said Commentary recently from his Nashville office. “But they don’t leave because of any fear of the weather.”
After the little ruby-throated creatures spend the spring, summer and early fall in the United States, they head south across the Gulf of Mexico because their built-in schedules tell them it’s time to. The fact they can make it that distance is a wonder in itself.
“As a human being, I’ll say this just isn’t possible. It’s pretty amazing stuff for a bird with a brain the size of a BB,” said Bob Sargent of Clay, Ala., a retired electrician with a longtime fascination for hummingbirds. “They fly by the clock. They’re going to go regardless.”
Perhaps part of the confusion about when the rubythroateds leave, he noted, is because of the arrival of other hummingbird species about the time the natives are departing. Those include the Rufous and Allen’s hummingbirds, coming from the West and even from Mexico.
“Unlike the ruby-throated, they are not cold-hearted,” Sargent said. “They come here and live during the winter. Their primary food is insects. A common misconception is that because frost has killed all of the flowers, they’ll starve. But they can find insects.”
The ruby-throats come back about the first of April, generally to the specific areas where they originally nested. Home feeders will likely attract the same ones from one year to the next. They are thought to cover the entire return trip within a single day, Sargent said.
Rufous birds may linger here until April or May.
While the same generation of birds that flies south returns, 80 percent of those that hatch in a particular year don’t live till their first birthday, Sargent said. Those that do, however, often survive for several years. The oldest known ruby-throated lived nine years, he related.
“The oldest (hummingbird) was a broad-tailed,” he added. “It was documented at 13. That’s the extreme.”
Female ruby-throateds are generally larger than the males. They hatch twice a year in the U.S. There are two eggs in each clutch, the female laying them two or three days apart.
“She will start to incubate that first egg immediately,” Sargent explained. “When they leave the nests, the babies can weigh almost twice as much as their mothers. They don’t learn to fly on the same day.”