I haven't done any real experimenting with frogs and trapping. Made one coon set one season with a bullfrog and it never hit.
I know from cat fishing that there are major differences in species. A bullfrog wont catch much. (fishing) Spring frogs will fill the boat with channel cats. One of my favorite baits. About all I use June July and August.
MIGHT be like that trapping
I catch them at night with a Maglite. Shine the light on them then grab them with the other hand. Works best if it hasn't rained in a week or so. They will be on pond banks or big puddle banks or creek banks. If you like catfish they are worth catching wherever you find them.