MEETING FRENZY FOR A COMMON SPECIES
In a beechwood of the Ligurian Apennines, every year in early spring, when snow and ice begin to melt, you can attend an extraordinary event: thousands of specimens of common frogs come out from their winter shelters and buried by snow, a leap after another one, they move to a pond that is located in the woods.
Sometimes they move so lonely, sometimes males ask “a passage” at the females: already laden of eggs, they have also bring the weight of the male along the way.
For these reasons the evolution processes have meant that female specimens of these frogs are larger than males. Reach the water is an essential goal for many amphibians, because only in this way the laid eggs can be fertilized and in the future bring the new generation.
Sometimes happens that the females are so full of eggs and exhausted from fasting of the long winter that have to leave the eggs in the snow in the woods, where are destined to become dehydrated and…die!
The males, once arrived in the pond, can start with the competition for the females. The reproductive frenzy is such that it is not unusual to find more than a male clinging to the same female.Happens that some specimens die suffocated or worn out by effort, even before they start to mate. This competition to seduce the females is necessary, since the fertilization takes place outside the body of the frogs. All they can do to secure offspring is contend the female “hugging” to be with her as much as possible during the deposition of the eggs. and release the sperm on their eggs thus ensuring fertilization.
All this happens in just over a week and, in some areas, the pond is so full of egg masses to form a sort of gelatinous carpet. Above it there are hundreds of frogs, perhaps to take a rest from the long swim sessions. The sound of this large number of specimens can be heard from several meters from the pond.
Almost like a long gurgle, is the only sound that combine the event along with the sound of the drops that fall from the trees in the snow not yet melted. Few weeks later, hundreds of thousands, perhaps millions of tadpoles, swim in the pond threatened by numerous predators; but they have a sufficient number to ensure new adults every year.
After the event the survivors disperse back into the woods waiting to do the same think next year in the same time and pond.