This rare species of toad is significantly smaller than the more frequent species of toad (Bufo bufo). In addition, natter jack toads have noticeably shorter legs, which they use to walk rather than hop, and they also have a narrow, bright yellow stripe that runs down the middle of their backs. The male natter jack gives a loud, rasping cry during the springtime, which is where the bird gets its popular name.
Males perform their mating calls from the bank of a pond at night throughout the months of April through July, which is the peak of the breeding season. Each female natter jack toad lays eggs in the shape of two separate "spawn strings," with the majority of the eggs in each string constituting a single row. The tadpoles are rather little and dark in color. Similar eggs are laid by common toads, although often there are two rows of eggs along each string. The tadpoles mature quite fast, and even the immature natter jack toad lets already have a distinct yellow dorsal stripe visible on their backs.