I have North American racers on my place, (blue racers for us old folks). The small ones are black with green speckles and green belly. The adults are all black.
Anyway, they assume a defensive posture when approached. They are non-poisionous, but wiggle their tail as if mimicking a rattlesnake. In the fall they wiggle their tail in dry leaves and sound like a rattlesnake.
I found a baby one in my RV garage about 1' long. It did the same as the adult I surprised when I approached it.
I caught it in a glass quart jar my holding the jar close in front of it. When it made a strike at my hand it went into the jar and I promptly fastened the lid.
After I'd made a positive ID I released it up the valley at my barn.
Racers are excellent mouse and spider eaters. My RV garage had a lot of mice 4 years ago, now there are no signs of mice.
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