TribLIVE

| USWorld


 
Larger text Larger text Smaller text Smaller text | Order Photo Reprints

Hummingbirds migrating earlier

Daily Photo Galleries

By The Associated Press
Sunday, Feb. 17, 2013, 9:12 p.m.
 

CHARLESTON, S.C. — 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 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.

The historical data on hummingbirds is based on government surveys from 3,000 naturalists 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The research compared the historical documents with about 30,000 recent records on hummingbird arrivals.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.

 

 
 


Show commenting policy

Most-Read Nation

  1. Edible pot ban proposed, yanked in Colorado
  2. Earth heads for record 2014
  3. GOP governors don’t see ‘Obamacare’ going away
  4. Indiana slaying suspect hints at more deaths
  5. High court will take case on gun ownership
  6. Over 3 years, extended federal leave adds up to $775M
  7. Navy civilian goes on trial for diverting $2M to brother of his boss
  8. Congress examines NSA official’s part-time job
  9. Revised Ebola guidelines stress full gear, training
  10. EPA hopes grants will reduce Lake Erie algae
  11. Crowd at Met protests ‘Death of Klinghoffer,’ calling opera anti-Semitic
Subscribe today! Click here for our subscription offers.