Frog, toad, newt: Amphibian offspring on the way

These days, the alpine newt looks particularly smart: During the mating season, the male's back turns blue. If he succeeds in winning a bride, she lays up to 250 eggs, which are individually attached to water plants. When the spawning season is over, the adult animals leave the waters and exchange their conspicuous coloring for their almost black camouflage suits once more.

The common toad is not only one of the most common amphibian species in Europe but, with a length of up to 11 centimeters (4.3 inches), also one of the largest. Its brown, warty skin does not make it a beauty, but the common toad is sporty: The female often carries the male piggyback during a couple's perilous migration to the water. Once there, the females lay egg strings with up to 6,000 eggs.

In the beginning, even the largest common toad (Bufo bufo) is a tiny dwarf. After about three months of existence as a tadpole, the toad offspring undergoes an amazing metamorphosis into a lung-breathing, four-legged land animal and leaves the waters where it was born. The common toad becomes sexually mature after about three to five years.

The midwife toad is distinguished by the fact that it takes care of its spawn —hence its name. It is the male that looks after the offspring. After fertilization has occurred on land, he takes over the egg lines from the female and wraps them around his hind legs. The toads distribute the spawn among several males. This way, they can reproduce up to four times a year.

The expectant midwife toad dad lugs the eggs around with him for the next 20 to 45 days. Only when the babies hatch does he carry them to a suitable body of water. The larvae either develop into a toad the same year or spend the winter as tadpoles in the water to go ashore the following spring.

Amphibians aren't cute? This little guy proves otherwise. When the egg containing the mini-fire salamander has fully developed inside her, the mother deposits it in the water along with up to 70 others. At this moment, the egg shells burst open and the fully developed, 25 to 35 millimeter (1 to 1.4 inch) larvae see the light of day.

The tree frog, which is just 3 to 5 centimeters long, is one of the best-known amphibians in central Europe and also one of the most popular. However, this, alas, is of little use to the frog: It is one of the most endangered amphibian species, too. In addition to suffering from the destruction of habitats, tree frogs, like many other amphibians, often meet their deaths when crossing roads.

The pool frog (Pelophylax lessonae) is widespread throughout Europe. It likes to live in small bodies of water that are low in nutrients. The small frog, up to 7.5 centimeters long, largely avoids large lakes and rivers. If the pool frog shares its habitat with a marsh frog, the two species can have joint offspring. These hybrids are called edible frogs or green frogs.