Catching a bullfrog is a challenging summertime activity in North America. It's a prey that require stealth and strategy to catch, but are also completely harmless. So remember to respect your quarry with careful handling.
Find bullfrog habitat. Bullfrogs dwell in freshwater lakes, ponds, rivers, and streams. They will tend to live where there is a tree canopy, cover such as cattails, and little to no current. Bullfrogs make a distinctive low-toned bass-like call, (sounds like a low "Ru-u-umm - Ru-u-umm").
Choose your tools. Bullfrogs can be caught bare-handed. However, you may want to consider other tools:
A net (such as a fishing net). One with a longer pole will work best!
A flashlight: The brighter the better- If you're hunting at night, you can use a flashlight to "jack" your bullfrog.
A Gig: Usually a fishing fly lure without a barb, the fishing lure imitates an insect. The frog eats it, and becomes easily caught.
A Container: If you're transporting the frog, consider what to put your amphibian in. A large plastic bucket will do, but bullfrogs can jump out unless there's a lid--bullfrogs are stronger than other common North American frogs. A bait bucket is an excellent choice as well.
A Frog Hotel: If you are planning to have your bullfrog visit a while, be sure to have a temporary habitat that can be set up for it. An aquarium with a secure lid is ideal. Remember that a bullfrog can jump up and knock off a lid that is not secured or weighed down.
Search for bullfrogs. When approaching frog habitat, move slowly and quietly. Stop and pause occasionally, as you are likely to spot frogs more easily if you search for movement on the banks or in the river.
Stalk Your Bullfrog. When you find a bullfrog, continue to move quietly and slowly. Bullfrogs react strongly to movement. Also, you may stumble on a closer bullfrog.
Position yourself for the pounce. After all this slow movement, be ready to pounce to catch your bullfrog. You will probably get only one chance.
If you are "jacking" a bullfrog, blind it. "Jacking" a bullfrog means using a strong flashlight directed at the frog's eyes (they shine the light back) at night. Blinded, the frog is easy to catch.
Use the Giggity-Giggity-Goo method. If you are "gigging" your frog, dangle your lure in front of the bullfrog and do your best insect impression. Be patient--bullfrogs usually do not bite right away.
Grasp the bullfrog firmly but gently. After grabbing or netting your frog, handle the frog with the same pressure as a bar of soap.
Hold the bullfrog properly. Hold the bullfrog by grasping around the "upper thighs" with its legs together. This position minimizes chance of injury, while making it difficult for the critter to get away.
Be kind to your web-footed friend. Now that you've caught your bullfrog, treat it humanely.
Bullfrogs seldom thrive in captivity, even with proper food, housing, environment, and so on. (Usually they just refuse to eat). The one possible exception is if a bullfrog is provided with a large outdoor pond.
If you choose to keep it for a while (a week at most), be sure to set up a safe, comfortable habitat for it, such as with a temporary terrarium. Keep it moist, cool, and out of the sun, and protected from dogs, cats, wild predators (like raccoons) and small children.
Bullfrogs live longer than other North American frogs, so they tend to be more intelligent than their smaller cousins.
Never grab a bullfrog (or any frog) by the legs--it could cause a fracture.
Frogs can see equally well from behind as in front.
It's always easier to capture frogs on land than in the water, with or without a net.
Frogs tend to swim downwards when panicked, so try to scoop with a net when hunting in the water rather than bring it downwards.
Bullfrogs do not have particularly long memories--so if you fail, try coming back in a few hours and try again.
Leave your dog at home. Most dogs will simply scare all the wildlife away.
Bullfrogs will scream when they are in distress (the scream sounds like a crying baby). If your bullfrog does this, release it immediately. It is very scared and unhappy.
Use insect repellent when hunting...frogs thrive where there are mosquitoes, chiggers, and black flies.
Respect property rights and posted areas while out in your hunts.
Make sure that what you are catching is in fact a bullfrog, and not some endangered frog that resides in your state!