Redpoll Finch Die-Off Baffles
Experts As Hundreds Die

From Patricia Doyle, PhD
From ProMED-mail
By Margaret Friedenauer
News-Miner - Fairbanks, Alaska
A record number of redpolls in the Fairbanks area this winter [2005] brought a colorful presence to bird feeders. Now, however, many of the red-capped finches are dying.
Reports of dead redpolls at household bird feeders in Fairbanks and Nenana have been increasing. Alaska Department of Fish and Game (ADF&G) suspected the birds were dying of salmonellosis bacteria. Such an outbreak was anticipated when it became apparent that redpolls would have a commanding presence in the area this season.
But Fish and Game wildlife veterinarian Kimberlee Beckmen said Sunday [6 Feb 2005] that preliminary cultures did not confirm salmonellosis. "The way the die-off was going ... it was very suspicious of salmonella," Beckmen said. Beckmen sent tissues from dead redpolls to the state public health lab last week [1st week of February 2005]. She received the results Friday [4 Feb 2005]. She sent another sample to the Washington Animal Disease Diagnostic Lab and expects those results today [7 Feb 2005].
Beckmen said the next likely affliction to cause a similar die-off is a mycoplasma organism. But the dead redpolls she has seen do not have corresponding signs. "I'm really very shocked it's not salmonella at this point," she said. "It should have been salmonella. I don't know what else it could be."
Beckmen said that if the Washington lab does not get a salmonella culture, it will continue to work on the sample until it isolates the cause. Whatever the outcome, Beckmen said it is likely the culprit is being passed from bird to bird at feeders and that bird enthusiasts should continue to take precautions as if the outbreak was salmonella. That includes cleaning feeders frequently and disposing of dead birds so that pets do not become infected.
Beckmen has not received reports of any sick or dying birds aside from redpolls. She said one Nenana resident called to report dying redpolls, but said chickadees at the same feeder were doing just fine.
Wildlife biologist John Wright said the high numbers of redpolls this year [2004] increased the chances of an outbreak. For several years in the late 1980s and early 1990s, the redpoll count went up and down before leveling off in the late 1990s.
This year [2005], the red-capped finches arrived early and in full force. Usually not seen in the area until January or February, record numbers were being spotted as early as October. The Christmas Bird Count documented 8231 redpolls in this year's annual tally, surpassing the previous record of 7164 redpolls counted in 1997.
Wright said the die-offs may startle some people, but suspects that less than one percent of the redpoll population is affected. "It's definitely a major mortality factor, but it's not affecting the population," he said.
Most disease, such as salmonella, is spread from bird to bird, and die-offs often occur in winter when birds are stressed from the cold and congregate at feeders. Feces contaminate the feeders and infect other birds.
Wright said the feeding characteristics of the gluttonous finches also contribute to outbreaks. "Redpolls just go sit and munch right there in the feeder," Wright said. Feces on and around the feeders then infect other birds. Pets, especially cats, can easily become infected if they come into contact with feces or dead birds. Humans are less likely to become seriously ill from an outbreak of salmonella among birds, a strain, Beckmen said that is similar to that found in uncooked poultry.
Wright said there hasn't been a die-off this broad in the area since a salmonella outbreak 10 or 12 years ago. The U.S. Fish and Wildlife Service reported an outbreak of salmonellosis in pine siskins in the Juneau area about 3 weeks ago.
While feeders are a major conduit of the bacteria, fish and game officials warn against removing feeders, because that can cause additional deaths from starvation. Rather, constant and vigilant cleaning can curb outbreaks. Feeders should be emptied, scraped, soaked and cleaned with hot soapy water, rinsed and disinfected with a one-to-9 part bleach and water solution. Clean feeders should be soaked in the bleach solution for up to 20 minutes, rinsed well and air dried. Wright said feeders should be cleaned once a week, if weather allows. He said it is also important to clean feces and debris from around the feeder.
Use caution when discarding dead birds by using a plastic bag to pick them up and disposing of them in a sealed bag and trash can where pets cannot get to them. Hands should be thoroughly washed after cleaning and filling feeders and discarding dead birds.
Anyone noting ill or dead birds is asked to notify ADF&G at 907 459-7206.,1413,113~7244~2697559,00.html
We hope that when Dr. Beckmen has a definitive diagnosis she will be kind
enough to share it with ProMED-mail. - Mod.TG
Patricia A. Doyle, PhD
Please visit my "Emerging Diseases" message board at:
Zhan le Devlesa tai sastimasa
Go with God and in Good Health



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