(this is a repost from the old forum)
I'm pretty passionate about drastically reducing the invasive species. It's such a stupid thing that people have done and it drives me bonkers to see folks actively encouraging them, especially once they know that they're invasive. I can only surmise that folks have no real grasp of the environmental damage (i.e. near monoculture or bi-culture of birds) that sparrows and starlings can do. They've nearly wiped out Bluebirds in our area.
What's cool, however, is that you can almost immediately see the benefits of an eradication program. In one season, I've transformed my neighborhood from a starling-sparrow-Pigeon haven to a zone where there are 2 pairs of chickadees feeding, hairy and downy woodpeckers, tons of gold finches, cardinals, junkos, titmice, and a number of other birds feeding and breeding.
To that end, I strongly advocate shooting and where you can't get a good clean shot, trapping both sparrows and starlings.
But, with such an advocacy, there's a very real need for some pretty discerning identification skills. There are song birds that look a lot like European house sparrows, especially female sparrows. And there are sparrows that are native (and wonderful--beautify songs). We need to be careful.
Here's a great link for differentiating between HOSPS and similar "brown birds".http://www.sialis.org/otherbrownbirds.htm
One rule of thumb, make sure that the breast is plain and not ticked or mottled. Also, make sure you keep binoculars handy. It's shocking how similar a house finch and a sparrow look from behind at certain times of the year. Make sure you can check out that breast (which is yet another reason for the new gun and scope).
I'll occasionally post more on this stuff, but I wanted to keep banging the good ID drum here, just like I bang the "don't feed, but kill" HOSP's drum on birder sites.
BTW, it's very odd, but once I started working on the sparrows, I've become something of a birder. I've always been an outdoors man, but never have I had much interest in watching birds. Now, after I've killed a hundred or so sparrows in a year, I'm absolutely enthralled by all the OTHER species.