Archive for October, 2010
Written by Lucy Brzoska
Montjuic, fragmented into a hundred spaces, often comes up with the unexpected. One of its disused quarries was landscaped into a steeply sloping garden, with carefully tended ornamental flower beds and terraced brick ponds. Layered with water lilies, these harbour an apparently vast number of Iberian Water frogs (Rana perezi or Pelophylax perezi)), whose massed choruses used to compete with the roar of Espanyol fans when their team still played in the Olympic stadium.
One of the ponds is thick with ribbon-like rushes, and a tall aquatic plant with large flat leaves. On one of these I noticed a small green blob, about half the size of my thumb nail, and realised there was a colony of Tree Frogs here too.
The species found in Catalunya is Hyla meridionalis, the Stripeless Mediterranean Tree Frog, but the pronounced black stripes in evidence here were confusing. Could this be an introduced Hyla arborea population? The distribution of the European or Common Tree Frog in Iberia is generally given as the north, north west and centre.
In fact, the juveniles of both species can have strong black markings, which shrink in adult Stripeless Tree Frogs. The Common Tree Frog is also fatter.
Feet tucked out of sight, they were clinging to stems and leaves, smooth, pea-green mounds. Unlike the Water frogs, which come in an infinite variety of green-brown combinations, Tree Frogs are quite uniformly coloured (though a rare blue morph crops up). The main variation is their size.
They’re inscrutable, with black stripes masking their eyes, like shadows permanently lying across them. The Water frogs leap almost as soon as you look at one, but these are easier to photograph, trusting in camouflage. When they do move, they reveal elastic-looking legs, and long toes tipped with round sticky pads.
With Tree Frogs imprinted on my mind, I began spotting them everywhere. Including one snoozing in the sun, camouflaged on a matching leaf, protruding right out of the park’s railings. You can see how the black stripe has faded away on this adult.
The season can betray them, though.