Then they try to pin the other underwater for a few minutes. Satellite males try to intercept females that are attracted to the resident male's territory. Sometimes they succeed, or sometimes they take over the resident male's territory while the resident is busy mating. When a female chooses her mate she approaches and touches him with a leg or nose. Then the male clasps onto her and they move away to deposit and fertilize the eggs.
Male bullfrogs have several aggressive calls given during territorial encounters.
Females lay an average of 7000 eggs in a surface film in the male's territory. These eggs hatch within two weeks. Some females lay two clutches of eggs in a season, or up to 40,000 eggs. They have white or cream colored bellies. They have very muscular tails, especially in older individuals.