The Karpathos frog (Pelophylax cerigensis) is a species of frog in the family Ranidae. Once considered as critically endangered, its range was thought to be restricted to two streams in the north part of Karpathos. However recent research implies the species also occurs on Rhodes Island. My understanding is this is a matter of opinion among scientists, but I prefer to believe our frogs are unique. The people of Olympos and Diafani are proud of them and so am I.
There are around 7600 species of frog in the world. New species are discovered each year and other species become extinct so the exact number varies. They have differing life styles; some give live birth, others swallow the spawn or tadpoles and spit them out to become baby frogs. Some lay eggs in tunnels, others build mud nests, or lay eggs in trees. Yet others have the male collect their offspring and carry them on their backs to spread through the forest floor. We know very little about the Karpathos frog. We visit them several times a year to count the number we observe. There are tadpoles in springtime but we have never seen frog spawn so it is possible they live birth their offspring. They also climb trees. Not very far, but when it looks as if rain is coming they move away from stream beds and up the banks to the lowest branches of local bushes. I think this behaviour stops them being swept away by floods, but have no idea how they know it is going to rain?
Our frogs prey on beetles, spiders, bees, woodlice wasps and ants and water boatmen. Low-scale habitat changes could be detrimental to the species due to very small number of individuals. Water availability is the main threat. Even in winter, the volume of water is limited. Forest fires are an additional threat. It is not only that the water table gets lower every year. Denuded mountainsides lead to stones, soil and pebbles rolling down and filling the river valleys so the stream is below ground level, there are fewer insects and limited scope for tadpoles.
As numbers fall there is limited connectivity among pockets of isolated frogs. What numbers survive have a narrow gene pool and are subject to sickness and disease. One pathogen which has decimated frog species throughout the world is the chytrid fungi. This can be carried on the feet of people and animals, and survives for 24 hours away from a host. It is essential, if you have arrived from Europe, that you do not go anywhere near local frog populations for 24 hours. And never handle them.
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