December 16, 2013

Bird Feeding

By Dave Erler

Over the years I have conducted a few workshops on bird feeding and the pros and cons of doing so. Since some people are surprised to hear that there are any cons to feeding birds, here are some considerations and myths about feeding wild birds.

How can feeding birds be anything but a good thing? In a biological sense, feeding wild birds is a wash as to whether birds benefit or are harmed by it. On the plus side, some species such as Northern Cardinals, Tufted Titmice, and Mourning Doves have probably been able to expand their ranges or increase their populations in northern New England due to bird feeding. In cold hard winters, many other bird species also benefit from an extra source of energy rich food.

On the negative side, if bird feeders are not strategically placed, they may increase the chance of birds becoming easier prey for predators, particularly house cats, or colliding with glass windows when startled. Bird feeding stations may also become a hot spot for birds to pick up bacterial and fungal diseases. Since feeders attract and concentrate both healthy and unhealthy birds, they increase the chance that diseases can be spread. Salmonella bacteria thrive in damp, soiled environments. When feeders accumulate old seed and bird feces, the result is prime conditions for Salmonella. This is a particular concern in late winter because the immune systems of birds, as well as most other wildlife, have been weakened due to the cumulative effects of winter stress. After a stretch of warmer damp weather in March (allowing Salmonella to thrive), people may find a few dead or dying birds in the yard while other sickened birds fall easy prey to predators. Feeders that keep seed dry and have perches that allow feces to drop clear of the feed help reduce this risk. On the other end of the spectrum, open flat tray feeders are probably the feeder style that will attract the most species but also require the most maintenance. Limiting the amount of seed placed on a tray feeder to that which can be cleaned up by birds in one day, as well as regularly cleaning the tray with a bleach solution, will greatly reduce this risk.

Another consideration is what species of birds are attracted to your feeders. If non-native House Sparrows or European Starlings are your most common visitors, it may be wise to discontinue feeding altogether. Why? These species are particularly aggressive and negatively impact many of our native species. The same can be said of Brown-headed Cowbirds, which have greatly expanded their range from the prairie states. Cowbirds have affected many of our native songbirds as they are parasitic nesters, dumping their eggs in other bird’s nests, with the resulting cowbird young aggressively out-competing the host bird’s young. The decline of such species as Wood Thrushes has at least been partially attributed to cowbird parasitism. Although other factors have helped cowbirds expand their range, bird feeding is certainly one.

So what are some myths about feeding birds?

  • Myth # 1 - Once bird feeding is started, you must continue because birds become dependent on feeders, and, if you were to discontinue for whatever reason, the birds will starve. Studies have shown that birds rarely get more than 20% of their daily calorie needs from feeding stations. Birds have survived for eons by opportunistically switching to what seasonable foods are available. Birds seem to be smart enough to know that an all-seed diet is not adequate for any species.
  • Myth #2 - Don’t feed birds in the summer because the young birds brought to the feeders will become lazy and dependent. Not true. If anything, parent birds bringing young to feeding stations may actually increase the young ones’ survival by exposing them to another food source. However, if you live in an area where bears are present, it isn’t wise to feed birds in the warmer months unless you are prepared to “bear proof” your feeders or take them in every night.
  • Myth #3 - It is not ethical to feed birds as those resources could be put to better use growing food that could feed the poor and starving. Although a purist might find traction with this concern, in reality, feeding birds is less of a resource drain than keeping household pets. The pet food industry far surpasses the bird food industry in the amount of resources consumed, so this argument only has standing if one chooses not to have a household pet.
There are other alternatives to attracting birds to your yard besides bird feeders. A well-maintained bird bath or landscaping with birds in mind are just two possibilities.

So why feed birds? It’s fun! If done responsibly, feeding birds provides hours of enjoyment and a sense of contact with the natural world. Bird feeding is a great introduction to nature study for both young and old. It can also be the first step in getting people to become more aware of and to care about the natural world around them.

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