I tried the tarp over the trap and every time I started towards the trap the tail came up. 

I had one at the foot of our deck and couldn't leave it there.  I ended up shooting it, only as I walked towards it it moved and I thought maybe I'd somehow missed.  Unfortunately I made the mistake of shooting it again and that time I must have hit the gland that sprays and it really stunk. 

Since then I put a long rope on the traps and can pull them away to a safe area where they can be dispatched and if they spray it's not as onerous.