This seems a bit obvious, but have you considered running some fecals on this snake? Regurgitation is not a normal activity of snakes and this is usually a sign that something is wrong (environmental or physiological). I would recommend keeping this snake far from any other herps until you know what's going on. A 3' coachwhip should have no trouble taking a young adult mouse so a fuzzy or hopper should be fairly easy. You might try a very large pinky just to see what happens but I would give the snake at least a couple of weeks off before trying again and in the meantime, get a fecal done.
Rob Carmichael, Curator
The Wildlife Discovery Center
>>So I recently purchased two absolutely stunning red western coachwhips...both of them are very aggressive feeders, the male, who is over four feet long, can take down adult mice with ease. However, the female, who is a little over three feet long, I'm having a bit of trouble with. She's thrown up her last two meals, which were hoppers, which it seemed like she had no problem taking down, but the next day, snake vomit. I haven't handled her after feeding or anything like that, and aside from the vomitting, she seems fine, very energetic and alert. Do you think the meal was just too big, maybe try fuzzies or something like that? Thanks
>>Kevin
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Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL