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MailTribune.com
  • Bird counters also keep eye on climate change

  • Groups of bird watchers heading out all over the U.S. this month for the 113th annual Christmas Bird Count are helping plot what appear to be significant global trends.
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    • If you go
      What: Christmas Bird Count
      When: In Medford, the count is scheduled for Saturday, Dec. 15. In Ashland, the count is scheduled for Thursday, Dec. 27.
      Information: For details about the Medford...
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      If you go
      What: Christmas Bird Count

      When: In Medford, the count is scheduled for Saturday, Dec. 15. In Ashland, the count is scheduled for Thursday, Dec. 27.

      Information: For details about the Medford count, contact Bob Hunter at bobhunter@embarqmail.com or 541-826-5569. Co-leaders for the Ashland count are Harry Fuller and John Bullock. Contact Fuller at 541-488-8077, anzatowhee@yahoo.com, or Bullock at 541-488-7962, jas@opendoor.com.
  • Groups of bird watchers heading out all over the U.S. this month for the 113th annual Christmas Bird Count are helping plot what appear to be significant global trends.
    For example, surveys indicate the goldfinch, Washington's state bird, may be looking northward for real estate in southern Canada, while the scrub jay in Oregon may find Washington more hospitable.
    Climate change has nearly 60 percent of the 305 bird species found in North America during winter on the move, said Gary Blevins, Spokane Community College biology professor.
    "In Southern Oregon, it is the alpine species that are being affected," says Pepper Trail, ornithologist with the U.S. Fish & Wildlife Service in Ashland. "They are like little islands in a sea of warmer climates, like islands in the ocean. As the temperature rises, it floods the habitat. There are not many alpine specialist birds in the Siskiyous, but we do have birds that will be affected by a loss of alpine habitat."
    Clark's nutcrackers and gray-crowned rosy finches are dependant on this habitat and are likely to be affected, Trail believes. The higher elevation, subalpine habitats will also be affected, impacting birds such as Cassin's finch, gray jay and red crossbill.
    Although Christmas Bird Count groups survey an area just 15 miles in diameter, they provide a snapshot of data added to the sightings from more than 2,000 circles across North America that helps scientists plot such trends.
    Last year, 2,248 counts and 63,223 volunteers in all 50 states and all Canadian provinces — plus 99 count circles in Latin America, the Caribbean and the Pacific Islands — tallied more than 60 million birds.
    Count leaders file their surveys of the number of birds and species online so central computers can organize the data into an impressive continent-wide picture.
    The Christmas Bird Counts occur on specific days between Dec. 14 and Jan. 5. In Medford, the count is scheduled for Saturday, Dec. 15. The Ashland count is scheduled for Thursday, Dec. 27.
    "This is not just about counting birds," said Gary Langham, Audubon's chief scientist. "Data from the Audubon Christmas Bird Count are at the heart of hundreds of peer-reviewed scientific studies and inform decisions by the U.S. Fish and Wildlife Service, the Department of the Interior and the EPA.
    "Because birds are early indicators of environmental threats to habitats we share, this is a vital survey of North America and, increasingly, the Western Hemisphere."
    In Southern Oregon, gray jays are particularly vulnerable to rising temperatures, Trail says.
    "They chew their food into a half-digested mass called 'bolas' — like chewing gum — then store it (gluing it to tree branches). It freezes and is preserved for later consumption. They rely on it for the winter," Trail explains. "As the winters get milder, it can thaw out the bolas."
    As regional temperatures rise, the size of the mixed conifer — Douglas fir and ponderosa pine — forests is likely to shrink, while the range of oak woodlands will expand. As the old saying goes, "in change there is opportunity."
    "There will always be winners and losers," says Trail. "Those species that live in oak woodlands will do better, for example, scrub jays, titmice, acorn woodpeckers, because their habitat will expand."
    As local forests change, birds from other areas are likely to move in.
    "Look to Northern California," Trail says. "Some may be invading from that area, like Lawrence's goldfinch, a species that like heat. Also blue grosbeak, California thrasher. It's hard to predict because there's so much we don't know."
    Habitat change is likely to produce "novel communities" of bird species.
    "There are going to be new levels of competition and different experiences with predation," says Jaime Stephens, research and monitoring director of the Ashland-based Klamath Bird Observatory. "We expect that this area is going to be a bit of a hot spot for those novel communities because of the uniqueness of the Klamath-Siskiyou bioregion: it's known for its high levels of biodiversity.
    "Generally the birds that are already at risk are going to be most susceptible to climate change as well, birds that include small geographic ranges, species that are dependant on highly seasonal resources, such as aerial insects or nectar, and long-distance migrants face multiple challenges such as the timing of food availability throughout their annual cycle."
    In particular, Stephens predicts that the hermit warbler and the rufous hummingbird will not fare well under climate change. Though they are both considered common species today, the goal for land managers, says Stephens, should be to "keep the common birds common" as well as protect the at-risk species.
    After decades of serving as the poster child in the battle over old-growth forests, the northern spotted owl is returning to the limelight, and climate change-induced wetter winters will play a central role.
    "Extreme events, particularly in the wintertime, can affect adult survivorship and the ability of (these) birds to successfully nest during the nesting season," says Dominick DellaSala, president and chief scientist of the Geos Institute in Ashland. "The birds are physiologically stressed when they have to hang around in extreme weather"… that's based on years of measurement."
    The spotted owl is at the center of a burgeoning land management controversy: competition from the more aggressive new invader, the barred owl. The U.S. Fish & Wildlife Service is poised to test a new strategy of shooting barred owls in selected locations to give the spotted owls a fighting chance.
    "The spotted owl faces this double whammy"… the competition with the barred owl, which is a tougher owl, if you will, and the combined loss of old forest habitat, says DellaSala. "Now you've got climate change that's entering the scene and that could be a triple whammy for the spotted owl."
    DellaSala is quick to admit that there are many unknowns in predicting the fate of specific local birds. But the big picture, he says, is clear.
    "If the climate is changing, the vegetation is changing," says DellaSala. "Eventually you're going to get a reshuffling of the deck of wildlife cards, because that's what birds are following, they're habitat-specific."
    Daniel Newberry is a freelance writer living in the Applegate Valley. You can reach him at dnewberry@jeffnet.org. Rich Landers of the The Spokesman-Review in Spokane contributed to this story.
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