Also, if you want to try to catch them, a good way is to use a pitfall trap. There are many ways to make a pitfall trap, but all of them involve burying a cup of some sort and waiting for insect to fall in and become trapped. You can google pitfall trap and find a bunch of different ways to do this. My favorite is to take a 2-liter soda bottle, cut the top off a short ways after if curves, then invert the top into the bottom such that the cut ends are aligned. Dig a hole then bury the trap so that the edge of the trap is even with ground. You can put bait in it before you set out the trap to increase your chances of catching roaches. I always heard that stale beer makes a good roach attractant but have never tried it. If you try using a pitfall, chances are you will come up with much more than just roaches, but hey, thats just more bugs to try out when you go fishing. Good luck.