With the arrival of spring and the rising temperatures, many species of amphibians have started playing. Russet frog (Rana temporaria ) Lowland they did in the fall and now it's the turn of the highland peoples who had spent the winter under the snow. Other species with a less differentiated phenology, such as common toads (Bufo bufo ) will use these days to make his productions. You only need to visit the blogs of friends ( 1 , 2) to realize that these last weeks the reproduction of this species is in full swing throughout our country ..
The toads are highly philopatric, ie they have a special fondness playing as the birthplace and repeated year after year in the same places. This means that in certain zones produce large concentrations of players for a few weeks a year in which males gather waiting for mature females come to spawn.
males are armed with patience and compete with other males for the best places and once the females will appear kicks and slaps to get hold of them. Most will not succeed and only those stronger and able to displace its rivals will mate successfully. Because of this, when we study the dynamics and genetics of a population is more important the concept of "effective population" which is the number of individuals that reproduce and thus pass their genes to the next generation, the total population , which includes the fraction that does not play.
The aims amplexus stimulate the female to perform the commissioning. The male presses his front legs and when she is ready arching his body and begins to expel the eggs. The male fertilizes them as they come out with their hind legs and grab the cord coming out of his cloaca and pull him thus helping to deportation (Click on the photos to view in more detail.) When you are finished spawning, a small bead filler transparent black eggs, which can reach several meters in length, eventually tangled branches and pebbles occupying much of the pond or stream.
But not all frogs reach their ponds, hundreds of them unfortunately being killed by cars and that much of the breeding sites are on the verge of roads and highways. Last night, in the town of Tuiza, on a stretch of about 30 meters we recently hit a 15 toads. Would require only a minimal investment by the government to prevent it, and of course just a little care and respect from drivers, but I fear that at least in our country that is a tall order.
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