VINS has received many reports of sick and dying
<http://www.birds.cornell.edu/BOW/CORE/>Common Redpolls at bird
feeders around the state. We have sent some samples for testing and
they have come back positive for Salmonella. We advise people to
clean their bird feeders with a 10% bleach solution and clean up all
seed waste that may be on the ground.
These birds come from the north where they may not be exposed to
pathogens common in our year-round backyard birds. Salmonella is
commonly isolated from House Sparrows for example. That, coupled with
the fact that they congregate in large numbers around a concentrated
food source and come into contact with infected droppings. The warm
weather this winter and lack of snow cover (on top of old seed on
ground to hide it and freeze it) has probably increased transmission.
Salmonellosis is caused by a bacteria belonging to the genus
Salmonella. It is a common cause of mortality in feeder birds, but
the symptoms are not always obvious. Sick birds may appear thin,
fluffed up, and may have swollen eyelids. They are often lethargic
and easy to approach. Some infected birds may show no outward
symptoms but are carriers of the disease and can spread the infection
to other birds.
It is primarily transmitted by fecal contamination of food and water
by sick birds, though it can also be transmitted by bird-to-bird
contact. Occasionally, outbreaks of the disease cause significant
mortality in certain species.
For more information visit the
Wildlife Health Center.
Conservation Biology Department
Vermont Institute of Natural Science
27023 Church Hill Rd.
Woodstock, VT 05091
Visit the CBD Blog: http://www.vinsweb.org/cbd/news.html