_VJCTN.webp)
The Italian pool frog, Pelophylax bergeri, is a water frog of the family Ranidae native to mainland Italy south of Rimini and Genoa, and the islands of Sicily, Elba and Corsica, with an introduced population on Sardinia and, uncertainly, one in the United Kingdom. It was first described by Rainer Günther in 1986, with the subspecific name honouring the Polish biologist Leszek Berger, and has since been shuffled between genera — from Rana through Hylarana before settling in Pelophylax in 2006 — reflecting a long-running debate over how water frogs relate to one another that continues today, since some authorities still treat it as a subspecies of the pool frog, Pelophylax lessonae bergeri, rather than as a full species.
Identification
Adults reach about 80 mm (8 cm) in snout-vent length, with a pointed snout and a triangular head. The skin is smooth rather than warty, and colouring is variable: most individuals show some shade of green with black spots, though reddish-brown or grey forms also occur, typically with a pale stripe running down the back and dark stripes along the hind legs; the underparts are greyish-white with dark markings. In the hand, the species also shows a notched tongue and vomerine teeth. Calling males inflate external vocal sacs and produce a series of guttural croaks, each lasting up to one and a half seconds, the easiest way to confirm the species’ presence at a pond after dark.
Habitat and range
The Italian pool frog lives in sluggish streams and rivers, lakes, swamps and their surroundings, from coastal lowlands up to elevations exceeding 1,800 m in the Apennines and other mainland ranges. That spread, from sea level to high mountain pools, across both the Italian mainland and several islands, makes it one of the more habitat-tolerant water frogs of the region, though it stays tied throughout to standing or slow-moving fresh water rather than fast rivers or the sea coast itself.
Behaviour and breeding
As with other pool frogs, males call from the water’s edge to attract females, using the guttural, vocal-sac-amplified croak described above; detailed population-level data on clutch size, breeding season and larval development for P. bergeri specifically has not been published in a source this page can cite, so the facts box omits those figures rather than borrowing them from a related species.
Conservation
The species’ facts box carries its current IUCN Red List category, Least Concern. The main pressure on the species is the draining of its aquatic habitats, which is causing a slow population decline, but its wide mainland and island range and generally common local populations keep it below a higher threat category for now.
Similar species
The closest relative is the pool frog, Pelophylax lessonae, from which P. bergeri was only split as a distinct taxon in 1986 and which some authorities still treat as the same species; a 2024 genetic study put the split between the Italian and European pool frog lineages at around 2.7 million years ago. The two are best told apart by range rather than by appearance at a glance, since P. lessonae does not occur in peninsular Italy.