I have been using a cottontail in distress call but have not had very good luck with it so far.
It may be the sounds you're making with it. It's impossible to describe the sound, but I learned from a cat. He had caught a cottontail, and the sounds I was hearing had me totally baffled until I looked outside and saw what it was. It was nothing like the "how to call" tapes you could buy back then. It was a frantic series of high volume - short duration calls that sounded just like a cottontail with his a$$ in the jaws of a predator!
The calls would go on for a very short time, then the cottontail would be quiet. The cat would give it a minute, then release it and then re-capture it as it tried to escape - then - a repeat of the screams!
I went out that evening (summer time) and set up in a logging road where I knew gray foxes were close. One series of calls and a fox almost ran over me!
Not all sounds will work in every location, and a lot of places have been over hunted and animals have been educated to calls, but the cottontail distress is still my #1 call to try first.
If you want to PM me with your phone number and a time you will be home I'll call and let you hear the sounds I use. (best done when my wife isn't home

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