A closeup of two pair of Wood Frogs (Lithobates sylvaticus) breeding in an ephemeral pool (vernal pool). The frogs are so interested in copulation that they don’t pay attention to what is going on around them. One pair is on top of the other pair, and they are facing in opposite directions. It is not unheard of in situations like this for the pair on the bottom to be accidentally drown. Their are egg masses (black in color) under and around the two copulating pair. In copulation the male Wood Frogs approach a female from behind, and clasps her with his front legs, behind her front legs, and then he hooks a digit on each front foot together in a hold called “amplexus” which is continued until the female deposits the eggs. When the female deposits her eggs the male fertilizes them. The deposited eggs usually attach to submerged substrate, typically vegetation, downed branches, or simply float. Most commonly, females deposit eggs adjacent to other egg masses, creating large aggregations of egg masses. The males are in their breeding colors, which varies from brown to blue gray. The females are always larger than the males, and they are less than two inches long.
A closeup of a pair of Wood Frogs (Lithobates sylvaticus) that were breeding in an ephemeral pool (vernal pool). The male (on top) was gripping the female so hard in amplexus (copulation grip) that it actually eviscerated the female. In trying to escape the male’s grip the female crawled up onto the bank where I took this photograph. If you look between the males right front, and rear legs you can clearly see some of the females intestines protruding from her body.