Berries beware.
Anchorage's annual winter invasion of nomadic flocks of chirpy Bohemian waxwings is exploding.
Initial tallies from the Christmas Bird Count sponsored by the Audubon Society indicate that more than 22,000 waxwings were seen by dozens of bird counters spread across Anchorage Dec. 20, the most ever tallied in the history of the count that goes back to 1941. How many is that?
• Nearly four times the 6,261 reported last year. And 2007 was when the waxwing was the bird most commonly seen in both Anchorage and statewide during the count. Some 13,590 were seen statewide.
• Nearly double the previous Anchorage high of 11,415 in 2004, which until this year was the only time the count exceeded 10,000.
• A sea change from the two waxwings counted in 1968 or the one seen in 1977.
"We had a really high count," said Sirena Brownlee, Anchorage Audubon's Field Trip Coordinator.
"They're an eruptive species, and sometimes you get huge numbers depending on the mountain ash crops. Participants were seeing very large flocks."
Bohemian waxwings feast on the red berries of mountain ashes and similar ornamental fruit trees in winter.
Anchorage pilot Bill Quirk, a retired federal government employee who's lived in Anchorage 40 years, believes the waxwing boom is linked to those mountain ashes.
"The big change in Anchorage came, I believe, in the early- to mid-1980s," he said.
"This was when the big oil companies like Arco and Exxon decided they wanted to beautify Anchorage by offering ornamental trees for planting in citizens' yards.
"The oil companies bought thousands of 2- to 4-foot sapling trees ... given away free ... to plant in your yard. The free-tree program went on for several years (and) thousands of trees were planted in yards all around Anchorage. A large percentage of the trees were mountain ash.
"That's an enormous food source."
Quirk said he sees flocks of 500 birds and, occasionally, perhaps up to 1,000.
"But by late February," he notes, "see if you can find a mountain ash tree with any berries."
Typically,waxwings move in unpredictable migration patterns and nest high in conifers, but much depends are where food is available.
"They can be spectacular to see," Brownlee said.
In addition to berries, waxwings feast on insects come summer.
John Hersh of Wasilla said he's spotted thousands in the Point Mackenzie area fattening up on leftover grain too.
Brownlee noted that last week's frigid Mat-Su temperatures may have pushed some waxwings into Anchorage.
"It was really cold in the Valley," she said. "That might have had something to do with it."
While many counters saw Bohemian waxwings, only one saw a Harris's sparrow.
This was only the second time in the history of the Anchorage's Christmas Bird Count that a Harris's sparrow, which breeds in Canada and typically winters in the central U.S. was seen.
Brownlee's group, which surveyed the Spenard and Turnagain areas, went out on the tidal flats too and counted about 200 rock sandpipers.
"That's pretty much the only shorebird that overwinters here," she said.
Find reporter Mike Campbell on line at adn.com/contact/mcampbell or call 257-4329.
For more information
• COUNT DETAILS: Full results should be posted on Anchorage Audubon's Web site this weekend. www.anchorageaudubon.org
• PAST BIRD COUNTS -- Check by species and location nationwide at audubon2.org/cbchist/count_table.html
By MIKE CAMPBELL
mcampbell@adn.com