Salmonella may not be the main culprit
The Washington Department of Fish and Wildlife is advising people to take down their seed feeders because of a widespread occurrence of dead and dying pine siskins from salmonella. Pine Siskins are small finches that travel and socialize in dense flocks. But salmonella is not always the main culprit. We are in the midst of a massive winter invasion of pine siskins because of the failure of seed and cone crops in boreal forests across Canada. Many of these birds arrive weak and emaciated because they have flown a long way with little or no food. I worry that taking down feeders could add to their problems.
Salmonella is a normal inhabitant of the bird gut; but can multiply in feces and contaminated seed if it is allowed to accumulate on feeder surfaces. The solution is to clean feeders often. That also applies to moldy seed and droppings that accumulate on the ground beneath feeders.
In the past, we’ve advised people to take feeders down for a week or two if they find dead or dying birds in order to prevent sick birds from reinfecting feeders. The dilemma is that starving birds may need this food to survive.
If you choose to feed birds, be sure to clean your feeders often.
Please don’t take hummingbird feeders down
I disagree with the WDFW advice to take down hummingbird feeders to stop the spread of salmonellosis among finches and other birds. Anna’s hummingbirds are thriving because more people are feeding them during the winter. As hummingbirds become more dependent on nectar feeders for winter survival, taking down feeders for an extended period can threaten their survival – especially now, as nighttime temperatures dip below freezing. Hummingbirds are at minimal risk of salmonella infection because they don’t frequent seed and suet feeders. And they have little contact with infected finches.
Many of the pine siskins driven south by the failure of cone crops further north, are emaciated and starving when they arrive here. Taking feeders down for a week or two is long enough to prevent previously sickened birds from re-infecting feeders. While the salmonella threat is serious, taking down seed feeders for longer periods may just add to their toll from starvation.
It may be unrealistic to expect people to keep their seed and suet feeders clean; but the preferred solution for many of us is to take seed and suet feeders down for a week or two, followed by regular cleaning and sanitizing. That includes raking and removing old seed and droppings from the ground beneath feeders.
Gene Bullock, President, Kitsap Audubon Society
Photo of Townsend’s Warbler provided by Don Willott