Water is a necessary medium for the
fertilization of spadefoot
eggs, and once the eggs hatch, water also provides a place for
tadpoles to mature to the adult stage. Because of the importance of water, spadefoots are active during the wet season spring and summer in the
Northern Hemisphere, and remain underground during the dry season (fall and winter). When a summer thunderstorm arrives, the male toads emerge from underground and look for pools of rainwater. When they find water, the males produce a
mating call that attracts female toads. New research has shown that females tend to be more attracted to bright-colored males over their dark-colored peers. Thus creating a new aspect in their determination of the male's size and condition. Because the pools of water may be short-lived, mating occurs the first night after rainfall begins. During reproduction, the male mounts the female and releases
sperm to fertilize the eggs, which are deposited in the pools of water in the form of a floating mass. The eggs hatch into tadpoles, which quickly mature into adults. They must reach this stage before the pool of water evaporates, and thus they sometimes mature in as little as 9 days after the eggs are laid. Western spadefoot toads take longer to mature (at least three weeks). The small pools of water are warmed by the
sun, which speeds up the growth of the tadpoles. Tadpoles will eat a variety of foods, such as small
insects near the pool and
algae, which they scrape off rocks. They also filter
microorganisms from the water as it is passed over their
gills. Tadpoles gather in wriggling masses, stir up the muck on the bottom of the pool, and filter out the organic nutrients. Unlike most tadpoles, which are exclusively
herbivores and
filter feeders, spadefoot tadpoles are
omnivores. They also eat dead
insects and tadpoles, as well as
fairy shrimp. ==References==