Description
provided by AmphibiaWeb articles
Vomerine teeth present. Posterior part of the tongue free and forked. Toes webbed. Omosternum and sternum ossified. Pupil of the eye horizontal. Body chunky (or corpulent). Snout moderately sharp. When the shins are positioned perpendicularly to the body axis, the heels do not contact. Inner metatarsal tubercle large. Dorsal coloration usually green, yellowish-green, olive-green or greyish-green with dark spots which vary in number, size and arrangement. Light middorsal line and lines on dorso-lateral folds regularly present. No temporal spot. Belly white or yellowish-white, usually without spots. Male and female flanks become more yellowish at the breeding time. Males differ from females by having paired white vocal sacs behind the mouth angles and nuptial pads on the 1st finger.In 2016 Orizaola and Laurila found that three populations of P. lessonae from the northernmost populations, isolated in the Uppland district north of Stockholm, Sweden, display greater thermal phenotypic plasticity than three populations from Poland (about the center of the species distribution) and Latvia (two from northern-edge populations). The Uppland populations show greater temperature-induced plasticity affecting duration of the larval period, mass at metamorphosis, and growth rate, than other populations. All these variables are important in facilitating positive responses to periodic warm spells in colder environments with shorter growing seasons. Geographic variation in plasticity of life history components should be considered in predicting responses of particular species to climate change.
Orizaola, German and Laurila, Anssi (2016). ''Developmental plasticity increases at the northern range margin in a warm-dependent amphibian.'' Evolutionary Applications, 9(3), 471-478.
- author
- Sergius L. Kuzmin
- author
- John Cavagnaro
Distribution and Habitat
provided by AmphibiaWeb articles
The species lives in Europe. The westernmost localities are in France (Garonne, Grenoble etc.) and Southern Italy. The southern margin of the range runs by Yugoslavia, Czech Republic, and Romania to the northwestern shore of the Black Sea, then from southern Ukraine northeastwards approximately along the line: Nikolaev Province - eastern part of Dnepropetrovsk Province and western part of Zaporozhie Province - southern part of Kharkov Province. Then it extends in Russia from Byelgorod Province to Voronezh Province, then northwards to Tambov Province then northeastwards to Penza Province and to the south of Ulyanovsk Province and to Samara Province. The northernmost localities are known from the Southern Norway and the Southern Sweden. From the southern coast of the Baltic Sea, the margin runs from Estonia to northwestern Russia, then eastwards and southeastwards approximately along the line: Leningrad Province - southern districts of Vologda Province - Kirov Province - Tataria and Bashkiria. From Tataria, the margin turns southwards to the northeast of Ulyanovsk Province and to Samara Province.Pelophylax lessonae inhabits deciduous and mixed forests. The frog penetrates steppe within forests and bushlands (e.g. riparian alder groves). It occurs primarily in stagnant water bodies such as lakes, ponds, swamps, large puddles and ditches, generally covered with dense herbaceous vegetation. The pools may be located within the forests, in glades and forest edges, in fields and flooded meadows. The frog occasionally stays in shallow pools along small rivers and streams. The presence of permanent water is necessary for the existence of P. lessonae populations. In the forest zone, when the air humidity is high, the frog frequently occurs on land far away from water bodies. Using chains of small ponds, the frog can migrate distances of up to 8 km.
- author
- Sergius L. Kuzmin
- author
- John Cavagnaro
Life History, Abundance, Activity, and Special Behaviors
provided by AmphibiaWeb articles
At most sites, this is a common amphibian. The population density of adults reaches one individual per few square meters of pond shore.Hibernation occurs from September - late November to March - May. Frogs hibernate in water, rarely on land (but then in holes and burrows). Reproduction extends from late March - May to late June. Males form breeding choruses. Amplexus is pectoral (axillary). The clutch contains 440 - 4400 eggs. Metamorphosis occurs from June to October, usually in July - August. The tadpoles sometimes overwinter reaching an especially large size. Sexual maturity is attained probably in the 2nd-3rd year of life. The maximum life span is 6-12 years in different populations.Tadpoles consume primarily algae: Cyanophyta, Chlorophyta etc. Juveniles eat large amounts of flies and fly larvae. They sometimes climb plant leaves (at a height up to 0.5 m) to forage. The food of adults consists mainly of terrestrial invertebrates (mainly insects). Aquatic organisms (Gerridae, Dytiscidae etc.) comprise usually less than a half of prey items. Feeding does not cease during the breeding season. The Pool Frog is not as voracious as the taxonomically and ecologically similar Marsh Frog (P. ridibunda), evidently due to its smaller body size. However, different amphibians and even juvenile grass snakes are consumed time by time.
- author
- Sergius L. Kuzmin
- author
- John Cavagnaro
Life History, Abundance, Activity, and Special Behaviors
provided by AmphibiaWeb articles
The species does not display overall decline, but local declines are known. They are caused usually by the same anthropogenic factors, as in P. ridibunda.Pelophylax lessonae went extinct in england in the mid 1990's. Reintroduction attempts using populations from Norway and Sweden (started in 2005) appear to have been successful (John W. Wilkinson & John Buckley, FrogLog 2012).
- author
- Sergius L. Kuzmin
- author
- John Cavagnaro
Relation to Humans
provided by AmphibiaWeb articles
Some populations of P. lessonae survive even in large cities. Frogs readily colonize fisheries, the settling reservoirs of wood-treatment enterprises, drains etc. The building of new ponds and channels by people promotes local dispersal and population increase in this frog. However, extensive and numerous dispersals as seen in the related species P. ridibunda are not known.
- author
- Sergius L. Kuzmin
- author
- John Cavagnaro
Biology
provided by Arkive
Pool frogs emerge from hibernation in spring, at a date depending on the weather conditions. They spend the first few weeks basking in the sun. Around mid-May, breeding begins, with the males croaking loudly by day and night. Females lay 2 or 3 clumps of spawn in the male chorusing area. The tadpoles feed on algae and detritus, and metamorphosis (when the tadpoles emerge as froglets) occurs from August-September. Pool frogs mature after 2-3 years. The adults feed on invertebrates, and take some flying insects by snapping at them as they fly past.
Conservation
provided by Arkive
The pool frog is a priority species under the UK Biodiversity Action Plan (UKBAP), and has been included in English Nature's Species Recovery Programme (SRP). An action plan was produced following surveys that concluded that the frog was probably extinct in the wild, and evidence increasingly indicated that native status was possible.
If the case for the native status of the pool frog is confirmed, re-introduction of the species to carefully selected sites will be attempted, subject to the necessary permissions. It is most likely that frogs from Sweden would be used for such a reintroduction. Measures to rectify the factors that led to the decline of the species have begun, and would continue alongside the reintroduction efforts.
Description
provided by Arkive
The pool frog was only recognised as a distinct species as recently as 1973. It is usually olive-brown above, with dark-brown blotches, and a prominent yellow line running down the centre of the back. Pool frogs from central and southern Europe are often green in colour. Pool frogs differ in shape from the common frog, having a more pointed snout, and they lack the dark patch behind the eye around the eardrum.
Pool frogs can be easily confused with two other species of frogs: the marsh frog and the edible frog (both introduced). They are best distinguished by a combination of characters, mainly geographic location, size, call, and to some extent coloration. Pool frogs have a loud call, somewhat similar to a duck quacking.
Habitat
provided by Arkive
Pool frogs tend to prefer permanent, un-shaded ponds which can warm up quickly. The pool frogs at the last known possibly native site were found in pingos, which are a special type of pond formed by depressions in the ground as relics of the last ice age. The species seems to thrive where there are many ponds in close proximity. Pool frogs also spend part of the year away from the breeding pond, dispersing across grassland and woodland.
Range
provided by Arkive
The pool frog is found across much of central Europe, as far north as Sweden and Norway (isolated populations only), and east to Russia. In the UK, they have only been recorded as possibly native from one site in Norfolk in recent years, with the last wild sighting in 1994. There has been much speculation as to whether the pool frog was native to the UK or an introduced species. Whilst there have been documented introductions in the past, recent evidence strongly indicates the species was in fact native to some areas. Evidence comes from genetic, vocalisation and fossil studies; taken together the information suggests that British pool frogs are most closely related to the Scandinavian pool frog populations. It was likely to have occurred in certain habitats in the east of England. Introduced pool frogs from central/southern Europe do occur at a few sites in England.
Status
provided by Arkive
The native form is currently extinct in the UK. This species is listed on Annex IV of the EC Habitats and Species Directive.
Threats
provided by Arkive
It is not fully understood exactly why the pool frog has disappeared from Britain, but it is likely that draining of wetlands, loss of suitable pools, successional changes to ponds, and growth of over-shading scrub have all contributed. 'Lucky', the last captive specimen from the Norfolk site, died in 1999.
Associations
provided by BioImages, the virtual fieldguide, UK
In Great Britain and/or Ireland:
Animal / predator
Rana esculenta is predator of imago of Donacia clavipes
Pool frog
provided by wikipedia EN
The pool frog (Pelophylax lessonae) is a European frog in the family Ranidae. Its specific name was chosen by the Italian herpetologist Lorenzo Camerano in 1882, in order to honour his master Michele Lessona.
Description
1897 sciagraph (X-ray photograph) of
P. lessonae (then
Rana Esculenta), from James Green & James H. Gardiner's "Sciagraphs of British Batrachians and Reptiles"
The pool frog is a small frog which rarely grows to more than 8 cm long, although females can grow up to 9 cm. Males are typically around 5 cm long, while females are around 6–6.5 cm long. These frogs are brown or green, with dark blotches along their backs, a pair of ridges running from each eye and a cream or yellow stripe down the middle of the frog's back. The vocal sacs on the male are cream or even white.[2]
Distribution
The pool frog is found across most of central Europe from the west coast of northern France to the Western part of Russia. There are also small populations of pool frogs in the United Kingdom, Spain, Sweden and Norway.[1] Pool frogs were previously thought to be a non-native species in the UK, but studies have shown that English pool frogs are related to the Swedish and Norwegian populations.[2]
The pool frog is found in damp areas with dense vegetation, or in calm, slow flowing rivers, ponds, bogs or marshes.[2]
According to Amphibiaweb populations of this frog survive in urban areas and even fisheries. The creation of new ponds and other bodies of water leads to increased dispersal and a growth in the population of these frogs.[3]
Pool frogs in Britain
Pelophylax lessonae is one of only four amphibian species recognized by the UK government as protected under its Biodiversity Action Plan. The reasons for declining populations are decreased pond habitat from human encroachment and also air pollution leading to over-nitrification of pond waters.
The pool frog has not always been recognised as a native British species. Part of the reason for this is that specimens are known to have been introduced from southern Europe (though not from Scandinavia). However research has now shown that the potentially native UK pool frogs are closely related to Scandinavian frogs, not to frogs from further south. A native origin is most likely.[4]
The Herpetological Conservation Trust website states that "The Pool Frog is a European frog and was formerly recorded from two sites in East Anglia although it was lost from one of these in the middle of the 19th century. It was presumed extinct in the wild at the last remaining site by 1995. A single individual known from this population survived in captivity until 1999. Other populations have become established in the UK and it is known that some of these included individuals of British origin in their founding stock."
An English Nature reintroduction project is underway in Breckland, where pool frogs were introduced to a single site in 2005.
Hybridogenesis
The edible frog Pelophylax kl. esculentus is a hybridogenetic hybrid of the pool frog Pelophylax lessonae and the marsh frog P. ridibundus. Its populations are maintained however through other crossings by hybridogenesis.[5]
References
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^ a b IUCN SSC Amphibian Specialist Group. (2022). "Pelophylax lessonae". IUCN Red List of Threatened Species. 2022: e.T58643A177068753. doi:10.2305/IUCN.UK.2022-1.RLTS.T58643A177068753.en. Retrieved 16 October 2022.
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^ a b c "Pool Frog". www.froglife.org. Retrieved 2022-05-25.
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^ "AmphibiaWeb - Pelophylax lessonae". amphibiaweb.org. Retrieved 2022-05-25.
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^ Beebee, Trevor J. C.; Buckley, John; Evans, Ivor; Foster, Jim P.; Gent, Antony H.; Gleed-Owen, Chris P.; Kelly, Geoffrey; Rowe, Graham; Snell, Charles; Wycherley, Julia T.; Zeisset, Inga (2005). "Neglected native or undesirable alien? Resolution of a conservation dilemma concerning the pool frog Rana lessonae". Biodiversity and Conservation. 14 (7): 1607–1626. doi:10.1007/s10531-004-0532-3.
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^ Berger, L. (1970). "Some characteristics of the crossess within Rana esculenta complex in postlarval development". Annales Zoologici. 27: 374–416.
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- Wikipedia authors and editors
Pool frog: Brief Summary
provided by wikipedia EN
The pool frog (Pelophylax lessonae) is a European frog in the family Ranidae. Its specific name was chosen by the Italian herpetologist Lorenzo Camerano in 1882, in order to honour his master Michele Lessona.
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- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors
