personally,
to enclose the amphibian frog creature ones would need a good area with a high awall as to prevent the creature from boinging over the walls and escaping,
personally id use the frog-hurder2000 designed especially for the job, this has a nice soft scoup and lite bristles to poke the beast and get it to move, i believe these retail at around £5.99?
good luck with hurding them :P