water bugs work well for channel cats...

all you need to catch them is a empty 2 litre bottle..
put some little pieces of food in it for bait...
and at night lay it in a water meter or anywhere you you have spoted these critters..
make sure to put something going to the mouth of the bottle so they have a way in ....
and presto once they are in they are stuck they wont be able to climb back out.....

now the way  i have fished these with success is by craming 1 or 2 on a hook and fishing botton  

or hooking one towards the back end and fishing with a bobber of some kind leave a sizeable leader so that it can act natural and swim....

this is the best channel bait i know of and channels of all sizes eat them ..... and they put off and odor so they will come from far off like useing STANK BAIT ..... so hope this works for you as well

never tried them either......you have to hook me up with some mike