"Killer" House Sparrows?
The House Sparrow (which is not a true sparrow, but in the Weaver Finch family) is just one of a number of non-native bird species that harm our native cavity-nesting birds, including the Eastern Bluebird. House Sparrows are the most abundant species of bird in North America, and are likely to remain in that position due to their great adaptability in feeding and nesting. The Starling is another, even worse, problem species for many more of our native birds. House Sparrows and Starlings can be very destructive, and at times I wish they all could just “go away”, but I don’t feel the “killer” label is appropriate.
There are a number of techniques (plugging, next box construction, trapping, etc.) that the Bluebird Society recommends to reduce the impact of House Sparrows, since they are going to be around human habitations whether we feed them or not. See http://www.nabluebirdsociety.org/sparrow.htm for more specifics. The only sure method to get rid of House Sparrows from an area is to remove the humans entirely! If you are attempting to encourage Bluebirds in your yard, anything you can do to discourage their competitors is appropriate. However, many of us don't have Bluebird habitat and want to encourage a wide variety of birds at our feeders.
Regarding feeding, House Sparrows are very opportunistic. I live in a typical suburban neighborhood, and feed the birds as Bluebird Bob suggests, though for different reasons. But I have dozens of House Sparrows that LOVE my black oil sunflower seed. When those feeders run empty they move over to my niger seed feeder. And they are always nibbling at the suet cake I have out. Other Audubon members I’ve asked also have the same experience.
So while mixes of seed (with millet, milo, corn and other grains) may be a House Sparrow’s first choice, they definitely eat – and enjoy – whatever you put out. So I see no reason to not use whatever mix of seeds you prefer. The advantage of using a mix is that you will attract ground-feeding species that do not eat sunflower seed, such as Juncos, Mourning Doves and the native, true sparrow species, such as White-throated and White-crowned Sparrows.
In the interest of full disclosure, I will point out that the Tulsa Audubon Society, www.tulsaaudubon.org, does sponsor an annual bird seed sale every Autumn with a variety of products, including mixes. Shops like Wild Birds Unlimited sell high quality mixes of seeds. I too advise skipping the cheap mixes that you can find in the grocery store, as they contain many filler items that only a House Sparrow would love!