Scaphiopus holbrookii Photo Fiona Sunquist ©
Spadefoot toads have evolved to live in semi-arid habitats. They burrow into the soil and remain there for days or weeks. Their digging is aided by the unique spade-like tubercles on their hind feet. If you look closely, the ‘spade’ appears as a sharp black ridge on the heel of each hind foot.
Photo Fiona Sunquist ©
When they dig themselves into the ground, these toads shuffle their feet, turn their body from side to side and rapidly sink into the ground within seconds.
Spade foots spend the day secure and hidden in their burrow, but at night they emerge to search for insects, worms and other prey. On summer nights following a thunderstorm, the hammock floor is covered with toads searching for food.
Many toads, including the spadefoot, are EXPLOSIVE breeders - on a single night, after a torrential downpour, thousands of individuals of both sexes gather at temporary pools to mate and lay eggs. At the water, males call to attract females. Call There are many more males than females at these temporary ponds and males will climb on and attempt to mate with almost anything that moves.
Spadefoot toads are adapted to breeding in these temporary pools, which often only last for a few weeks. Their eggs hatch in 1-2 days, and the tadpoles feed continuously and metamorphose into toadlets within two weeks. For protection against predators, tadpoles usually remain together in dense swarms. When they leave the water, the toadlets are about the size of a raisin. Masses of them disperse into the forest – in a good toad year there can be so many of them that they blanket the ground to the extent that it is impossible to walk without crushing them. In one hatch, photographed near a pond in the Ocala National Forest, Florida, an estimated one million toadlets carpeted the ground. Rather than refer to it as a ‘plague’ of toads, biologists have dubbed the phenomenon a “jubilee”.
Spadefoots breed only in ephemeral or extremely short-lived ponds. Most of these ephemeral breeding ponds appear only as dry depressions in the woods until a heavy rain fills them with water. The advantage of breeding in these temporary ponds is that tadpoles do not have to contend with the usual complement of fish and aquatic insects that normally prey on tadpoles. The disadvantage is that these depressions are often used as trash dumps or filled in by developers or homeowners who do not understand their importance.
top of page | back to frogs / toads