Are you using a meat type bait ?Hedgehogs shouldn't enter a trap if you're using grain as bait, but rats will.
I caught hedgehogs for 9 or 10 days in a row in a cat trap when using dog food as bait.
On the 2nd last day I marked the Hedgehog with a bit of whitewash and sure enough he was in the trap the next morning.
I had been catching the same one all along.
I've caught plenty of hedgehogs in cages baited with nuts for squirrels or carrot and apple for rabbits. Strange but it happens
There you go, hunting or trapping any animal will always ,eventually, make a liar of us, LOL.Glad to