CHARLESTON, S.C. (AP) — Ruby-throated hummingbirds are migrating to North America weeks earlier than in decades past, and research indicates that higher temperatures in their winter habitat may be the reason.
Researchers say the early arrival could mean less food at nesting time for the tiny birds that feed on insect pests, help pollinate flowers and are popular with birdwatchers.
"Hummingbirds are charismatic, and they do things that fascinate us," said Ron Johnson, a scientist at Clemson University and one of the study's authors. "They fly backward, and they hover, and they will come to feeders at homes so people can easily see them."
Johnson and colleagues from Clemson; Taylor University in Upland, Ind.; and the University of Nebraska last month published an article on the migration of the hummingbirds in The Auk, the Journal of the American Ornithologists Union.
The birds, which weigh little more than a nickel, fly hundreds of miles over the Gulf of Mexico from their wintering grounds in Central America to arrive in North America. The research compared data on their first arrival times from 1890 to 1969 with arrival times during the past 15 years or so.
The comparison found that the birds are arriving in North America 12 to 18 days earlier than in the past.
Jason Courtier of Taylor University said the historical data on hummingbirds is based on government surveys from about 3,000 naturalists around the country who recorded the first spring arrival time of bird species over the decades.
About 6 million such records exist and are being scanned into computer databases by the North American Bird Phenology Program.
The research compared the historical documents with about 30,000 recent records on hummingbird arrivals. Scientists say the earlier arrival times could be problematic for hummingbirds, of which there are an estimated 7 million.
"With any bird that migrates over long distances, it's good to show up at the nesting grounds at a good time when you can set up a territory and build your nest and when the young come along there will be a lot of food available," Johnson said.
"You want to be there ideally right when the food becomes available at its peak so the young ones will have enough food."
Ecological systems work differently, Johnson said, and the hummingbirds' early arrival doesn't necessarily mean that the flowers and insects of their diet are available earlier.
Courtier said future research might focus on other species farmers needed for pollination of plants.
"We're wondering what the consequences are and are hummingbirds representative of other species farmers rely on for other pollination and biological pest control," he said.
James Van Remsen, the curator of birds at the Museum of Natural Science at Louisiana State University, said that while he had not seen the hummingbirds research, a wide body of literature shows other species of birds flying north earlier in both North America and Europe.
But he added that sometimes too much emphasis is placed on the earliest date a bird appears. It could reflect a couple of extremely early arrivals, he said.
"What really counts, biologically, is whether the peak period of migration has actually changed," he said. "That is what would most likely affect population biology."
MAY 24 Blogger Robert Mann posts this entry about the Baton Rouge Chamber's recent report on Louisiana's higher education system. It's critical to economic development, and yet our system is facing a "funding crisis" with no way to resolve it, the report says. The Chamber says control of tuition and fees must be returned to the higher ed governing boards.
MAY 24 Here's a NBC33 story about Tyrann Mathieu. He has signed with the Arizona Cardinals, inking a $3 million, four-year deal. He gets a signing bonus of $265K, but gets another, larger bonus if he doesn't get cut from the team for doing drugs. The deal reportedly includes mandatory tests and meetings for the player.
MAY 24 Jarvis DeBerry posts here about the redonkulus rhetoric that would have us believe NOLA is a safe city with a murder problem. Maybe the city's crime stats don't compare with its murder stats because you can't manipulate a murder, he says: a dead body's a dead body. It just doesn't make sense, he says, and his readers agree: a poll asks if they believe the city is safe, and more than 90 percent say no.
MAY 24 Jindal administration officials announced Thursday that the privatization of public health care is going to cost a lot more than they budgeted for, the Advocate reports here. "I'm so surprised," said no one. Anywhere. The cost they're projecting now is more than $1 billion - a lot more than the $626 million budgeted for it. And, it's more than it cost the state to operate those hospitals. So why are we doing this again?
MAY 24 Blogger CB Forgotston ridicules the recent PR campaign by the state GOP in the wake of a legislative auditor's request to both major parties. The GOP (apparently unaware that the Dems got the same request) started yammering about being targeted because it had "killed" a tax increase. CB finds that laughable, but it's also pretty funny that the GOP was comparing this episode to the IRS scandal (Because the President has so much to do with our state auditor. Right?).
MAY 24 Politico details some recent fund-raising efforts by Sen. David Vitter, which have raised the question of his future political plans. This time, it is a $5,000 per head "bayou weekend" that includes "Cajun cooking" and an all-caps "alligator hunt," the story reports. Funds raised go to a super PAC that can spend money to support Vitter in federal or state races, the story points out.
MAY 24 The pink building on Royal in the quarter was sold at a sheriff's sale Thursday, this Picayune story reports. An injunction that would have halted the sale wasn't enforced because the family failed to post a $150,000 bond, the story reports. So the owner of the mortgages on the building bought it, for nearly $7 million. Now the feuding family will have to negotiate with that company to get a lease on the building that has housed their business for close to 60 years.
MAY 23 This post in Louisiana Voice tells us about a bill by a Winnsboro lege that would require all public high school students to take at least one Course Choice online class in order to graduate. (What?) Blogger Tom Aswell says it's a monument to "waste and corruption," especially in light of the problems he's exposed with the program in recent weeks. Idaho had a similar program, but voters removed it by a 2-1 margin, Aswell says.
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