Editing Common frog

{{Short description|Species of amphibian}}
{{other uses}}
{{Use dmy dates|date=June 2023}}
{{Speciesbox
| image = European Common Frog Rana temporaria.jpg
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="Kuzmin 2008">Kuzmin, S., Ishchenko, V., Tuniyev, B., Beebee, T., Andreone, F., Nyström, P., Anthony, B.P., Schmidt, B., Ogrodowczyk, A., Ogielska, M., Bosch, J., Miaud, C., Loman, J., Cogalniceanu, D., Kovács, T. & Kiss, I. (2009). ''Rana temporaria'' (errata version published in 2016). The IUCN Red List of Threatened Species 2009: {{doi|10.2305/IUCN.UK.2009.RLTS.T58734A11834246.en}}</ref>
| taxon = Rana temporaria
| authority = [[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]
| subdivision_ranks = Subspecies
| subdivision = *''R. t. temporaria''
*''R. t. honnorati''
*''R. t. parvipalmata''
| range_map = Mapa Rana temporaria.png
| range_map_caption = Distribution of ''Rana temporaria'' in Europe
}}
[[File:Rana temporaria 120329-015849.ogg|thumb|Male ''Rana temporaria'' calling in a garden pond in [[Jambes]], Belgium]]
The '''common frog''' or '''grass frog''' ('''''Rana temporaria'''''), also known as the '''European common frog''', '''European common brown frog''', '''European grass frog''', '''European Holarctic true frog''', '''European pond frog''' or '''European brown frog''' or simply the '''frog''', is a [[Semiaquatic|semi-aquatic]] [[amphibian]] of the family [[Ranidae]], found throughout much of Europe as far north as [[Scandinavia]] and as far east as the [[Urals]], except for most of the [[Iberian Peninsula]], southern Italy, and the southern [[Balkans]]. The farthest west it can be found is Ireland. It is also found in Asia, and eastward to Japan. The nominative, and most common, subspecies '''''Rana temporaria temporaria''''' is a largely terrestrial frog native to Europe. It is distributed throughout northern Europe and can be found in Ireland, the [[Isle of Lewis]] and as far east as Japan.<ref name="BBC">{{cite web |publisher=[[BBC]] |work=Nature Wildfacts |title=Common frog, grass frog |url=http://www.bbc.co.uk/nature/wildfacts/factfiles/483.shtml |url-status=dead |archive-url=https://web.archive.org/web/20021028090843/http://www.bbc.co.uk/nature/wildfacts/factfiles/483.shtml |archive-date=2002-10-28 |access-date=2007-08-09}}</ref>

Common frogs [[Metamorphosis|metamorphose]] through three distinct developmental life stages&nbsp;— aquatic [[larva]], terrestrial juvenile, and adult. They have corpulent bodies with a rounded snout, webbed feet and long hind legs adapted for swimming in water and hopping on land. Common frogs are often confused with the common toad (''[[Bufo bufo]]''), but frogs are easily distinguished by their longer legs, hopping movements, and moist skin, whereas toads crawl and have a dry 'warty' skin. The spawn of the two species is also different, with frogs laying their eggs in clumps and toads in long strings.

There are 3 subspecies of the common frog, ''R. t. temporaria'', ''R. t. honnorati'' and ''R. t. palvipalmata''. ''R. t. temporaria'' is the most common subspecies of this frog.

==Description==
The adult common frog has a body length of {{convert|6|to|9|cm|in|1}}.<ref name="Complete">{{Cite book|last= Sterry|first= Paul|title= Complete British Wildlife Photoguide|year= 1997|publisher= [[HarperCollins]]|location= London|isbn= 0-583-33638-8 }}</ref> In addition, its back and flanks vary in colour from olive green<ref name="BBC"/> to grey-brown, brown, olive brown, grey, yellowish and [[rufous]].<ref name="Amphibia"/> However, it can lighten and darken its skin to match its surroundings.<ref name="BBC"/> Some individuals have more unusual colouration—both black and red individuals have been found in Scotland, and [[albino]] frogs have been found with yellow skin and red eyes. During the mating season the male common frog tends to turn greyish-blue (see video below). The average mass is {{convert|22.7|g|oz|abbr=on}}; the female is usually slightly larger than the male.<ref name="BBC"/>
[[File:Rana temporaria tadpoles eating 8.jpg|thumb|Captive common frog tadpoles eating a crushed garden snail]]
[[File:RanaTemporariaMaleThumb.JPG|thumb|Male during breeding season showing the nuptial pad, white throat and a blue grey hue over the normal black and brown skin]]
[[File:Rana_Temporaria_After_Egg_Laying_Mid-Norway_May_2013.jpg|thumb|Common frog mass spawning event in the wild]]

The flanks, limbs and backs are covered with irregular dark blotches<ref name="BBC"/> and they usually sport a [[Chevron (insignia)|chevron]]-shaped spot on the back of their neck and a dark spot behind the eye.<ref name="Amphibia"/> Unlike other amphibians, common frogs generally lack a mid-dorsal band but, when they have one, it is comparatively faint.<ref name="Amphibia"/> In many countries [[moor frog]]s have a light dorsal band which easily distinguishes them from common frogs. The underbelly is white or yellow (occasionally more orange in females) and can be speckled with brown or orange.<ref name="BBC"/> The eyes are brown with transparent horizontal pupils, and they have transparent inner eyelids to protect the eyes while underwater, as well as a 'mask' which covers the eyes and eardrums.<ref name="BBC"/> Although the common frog has long hind legs compared to the [[common toad]], they are shorter than those of the [[agile frog]] with which it shares some of its range. The longer hind legs and fainter colouration of the agile frog are the main features that distinguish the two species.

Males are distinguished from females by being smaller and having hard swellings known as [[nuptial pad]]s, on the first digits of their forelimbs, which are used to grasp females during mating.<ref name="Complete"/><ref name="BBC"/> During the mating season males' throats often turn white, and their overall colour is generally light and greyish, while the female is browner, or even red.<ref name="Amphibia"/>

These smooth-skinned frogs can grow to an average weight of 22.7 grams and length of seven to ten centimeters (2.8-3.9&nbsp;in) with colors varying from gray to green, brown, yellow, or red and may be covered in blotches.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/128297/common-frog|title=Common frog &#124; amphibian &#124; Britannica}}</ref> The underside is white or yellow, often with spots.<ref name="BBC"/>

==Habitat and distribution==
Outside the breeding season, common frogs live a solitary life in damp [[wetland]] [[ecological niche|niche]]s near ponds or marshes or among long [[riparian]] grass.<ref name="Roots">{{cite book |author=Roots, Clive |title=Hibernation |publisher=Greenwood Press |location=Westport, Conn |year=2006 |pages=510, 511 |isbn=0-313-33544-3}}</ref> They are normally active for much of the year, only [[hibernating]] in the coldest months.<ref name="Amphibia"/> In the most northern extremities of their range they may be trapped under ice for up to nine months of the year, but recent studies have shown that in these conditions they may be relatively active at temperatures close to freezing.<ref name="Roots"/> In the [[British Isles]], common frogs typically hibernate from late October to January. They will re-emerge as early as February if conditions are favorable, and migrate to bodies of water such as garden ponds to spawn.<ref name="enfo">{{cite web |title=The Common Frog – (''Rana temporaria'') |work=enfo.ie |publisher=ENFO |url=http://www.enfo.ie/leaflets/bs33.htm |access-date=2007-08-09 |url-status=dead |archive-date=28 September 2007 |archive-url=https://web.archive.org/web/20070928111934/http://www.enfo.ie/leaflets/bs33.htm}}</ref> Where conditions are harsher, such as in the [[Alps]], they emerge as late as early June. Common frogs hibernate in running waters, muddy burrows, or in layers of decaying leaves and mud at the bottom of ponds or lakes primarily with a current. The oxygen uptake through the skin suffices to sustain the needs of the cold and motionless frogs during hibernation.<ref name="BBC"/><ref name="Amphibia">{{cite web|url=https://amphibiaweb.org/cgi-bin/amphib_query?where-genus=Rana&where-species=temporaria |access-date=2007-08-09|last=Kuzmin|first=Sergius L.|date=10 November 1999|title=''Rana temporia'' |publisher=AmphibiaWeb}}</ref><ref>{{Cite web|title=Common Frog final|last=Dunlop|first=David|date=26 February 2004|publisher=Lancashire BAP|url=http://www.lbap.org.uk/bap/urban/Microsoft%20Word%20-%20Common%20Frog%20final.pdf|access-date=2007-08-09|archive-date=27 September 2007|archive-url=https://web.archive.org/web/20070927161321/http://www.lbap.org.uk/bap/urban/Microsoft%20Word%20-%20Common%20Frog%20final.pdf|url-status=dead}}</ref>

Common frogs are found throughout much of Europe as far north as northern Scandinavia inside the [[Arctic Circle]] and as far east as the [[Urals]], except for most of the [[Iberian Peninsula|Iberia]], southern Italy, and the southern [[Balkans]]. Other areas where the common frog has been introduced include the [[Isle of Lewis]], Shetland, [[Orkney]] and the [[Faroe Islands]]. It is also found in Asia, and eastward to Japan.<ref name="BBC"/><ref>[http://jenskjeld.info/UK_side/indexuk.htm ''Rana temporaria'' have established themselves as a wild population in Nólsoy]. jenskjeld.info</ref>

The common frog has long been thought to be an entirely introduced species in Ireland,<ref name="enfo"/> however, genetic analyses suggest that particular populations in the south west of Ireland are indeed indigenous to the country.<ref name=IrlFrog1/> The authors propose that the Irish frog population is a mixed group that includes native frogs that survived the [[last glacial period]] in ice free [[refugium (population biology)|refugia]], natural post-glacial colonizers and recent artificial introductions from Western Europe.<ref name=IrlFrog1>{{cite journal|issn=0018-067X|volume=102|issue=5|pages=490–496|last=Teacher|first=A. G. F.|author2=T. W. J. Garner |author3=R. A. Nichols |title=European phylogeography of the common frog (''Rana temporaria''): routes of postglacial colonization into the British Isles, and evidence for an Irish glacial refugium|journal=[[Heredity (journal)|Heredity]] |date=21 January 2009|doi=10.1038/hdy.2008.133|pmid=19156165|doi-access=free}}</ref><ref>{{cite web |url=http://www.zsl.org/science/news/irish-frogs-may-have-survived-ice-age,568,NS.html|title=Irish frogs may have survived Ice Age|publisher=[[Zoological Society of London]]|date=17 March 2009|url-status=dead |archive-url=https://web.archive.org/web/20090618224252/http://www.zsl.org/science/news/irish-frogs-may-have-survived-ice-age,568,NS.html|archive-date=18 June 2009}}</ref>

=== Genetic population structure ===
The common frog is a very widely distributed species, being common all throughout Europe and northwest Asia. The more peripheral subpopulations of common frogs are significantly less in number, as well as less genetically variable. There is a steep genetic decline when approaching the periphery of the common frog's distribution range.<ref name=Johansson>{{cite journal |last1=Johansson |first1=Markus |last2=Primmer |first2=Craig R. |last3=Merilä |first3=Juha |date=14 March 2006 |title=History vs. current demography: explaining the genetic population structure of the common frog (''Rana temporaria'') |doi=10.1111/j.1365-294X.2006.02866.x |journal=Molecular Ecology |volume=15 |issue=4 |pages=975–983 |pmid=16599961 |bibcode=2006MolEc..15..975J |s2cid=30974911 |ref=Demography}}</ref> Additionally, genetic differentiation of common frog subpopulations tends to decrease in relation to increasing latitude.<ref name=Johansson/> The colder climates create a strong selective pressure favoring common frog populations able to behaviorally [[Thermoregulation|thermoregulate]] at a high degree.<ref name="Ludwig-2015" />

==Conservation ==

=== Long-term impact of diseases ===
Of the many diseases that affect common frogs, one of the most deadly is [[Ranavirus]], which has been responsible for causing declines in amphibian populations worldwide. Two of the most important and deadly symptoms caused by ranavirus in common frogs are skin ulcerations and [[Bleeding|hemorrhaging]].<ref name="Teacher-2010">{{cite journal |last1=Teacher |first1=A. G. F. |last2=Cunningham |first2=A. A. |last3=Garner |first3=T. W. J. |date=10 June 2010 |title=Assessing the long-term impact of Ranavirus infection in wild common frog populations: Impact of Ranavirus on wild frog populations |journal=Animal Conservation |volume=13 |issue=5 |pages=514–522 |doi=10.1111/j.1469-1795.2010.00373.x|s2cid=85889833 }}</ref> Mortality rates associated with the disease are very high, in some cases exceeding 90%.<ref name="Teacher-2010" /> Deaths caused by ranavirus occur at all stages of the common frog's lifecycle and are concentrated mostly during the summer months. Overall, populations of common frog affected by ranavirus experience consistent and substantial declines in population size. Recent metagenomic studies of common frogs from the UK have revealed widespread viral infections with Rana tamanavirus, a positive-sense RNA virus that is closely related to Tamana bat virus, with no pathology or effects on life history traits observed to date.<ref name="pmid38059479">{{cite journal| author=Parry RH, Slonchak A, Campbell LJ, Newton ND, Debat HJ, Gifford RJ | display-authors=etal| title=A novel tamanavirus (Flaviviridae) of the European common frog (Rana temporaria) from the UK. | journal=J Gen Virol | year= 2023 | volume= 104 | issue= 12 | pages=  | pmid=38059479 | doi=10.1099/jgv.0.001927 | pmc=10770923 }} </ref>

=== Impact of urbanization ===
Due to the widespread nature of ''Rana temporaria'', common frogs can make their homes in both urban and rural environments. However, many of the populations living in urban areas are subject to the detrimental effects of urbanisation. The construction of roads and buildings – absolute barriers to migration – has prevented [[gene flow]] and [[Genetic drift|drift]] between urban populations of common frogs, resulting in lower levels of genetic diversity in urban populations of common frog compared to their rural counterparts.<ref name="Hitchings-1997">{{cite journal |last1=Hitchings |first1=Susan P. |last2=Beebee |first2=Trevor J. C. |date=August 1997 |title=Genetic substructuring as a result of barriers to gene flow in urban Rana temporaria (common frog) populations: implications for biodiversity conservation |journal=Heredity |volume=79 |issue=2 |pages=117–127 |doi=10.1038/hdy.1997.134|pmid=9279008 |s2cid=6284299 |doi-access=free }}</ref> Urban common frog populations also experience higher levels of mortality and developmental abnormalities, indicating forced [[inbreeding]].<ref name="Hitchings-1997" />

However, the common frog is listed as a species of [[least concern]] on the [[IUCN Red List|IUCN Red List of Threatened Species]].<ref name="Kuzmin 2008" />

== Diet ==

=== Juvenile ===
During metamorphosis, when the tadpole's front legs have developed, the frog stops eating for a short time. Recently metamorphosed juveniles feed mainly on small insects such as [[Springtail|Collembola]] (hexapods), [[Mite|Acarina]] (mites and ticks), and small fly larvae. ''Rana temporaria'' tadpoles. However, they mostly feed on algae and decomposed plants,<ref name="Stojanova-2008">{{cite journal |last1=Stojanova |first1=A. |last2=Mollov |first2=I. |date=2008 |title=DIET AND TROPHIC NICHE OVERLAP OF THE MOOR FROG (Rana arvalis Nilsson, 1842) AND THE COMMON FROG (Rana temporaria L., 1758) FROM POLAND |s2cid=83200707 |language=en |ref=food3}}</ref> but when their hind legs develop, they become carnivorous.<ref>{{Cite web |title=Tadpole to frog: development stages & metamorphosis – Saga |url=https://www.saga.co.uk/magazine/home-garden/gardening/wildlife/amphibians/the-tadpole |access-date=2023-03-17 |website=saga.co.uk}}</ref>

=== Adults ===
The common frog takes its place as an unspecialized and opportunistic feeder wherever it is found. In other words, common frogs will consume whatever prey that is most available and easy to catch.<ref>{{cite journal |last1=Houston |first1=W. W. K. |date=October 1973 |title=The food of the Common frog, Rana temporaria, on high moorland in northern England |journal=Journal of Zoology |language=en |volume=171 |issue=2 |pages=153–165 |doi=10.1111/j.1469-7998.1973.tb02212.x |issn=0952-8369 |ref=Food1}}</ref> This usually means that the common frog feeds by remaining inactive and waiting for a suitable prey to enter the frog's area of capture. This also means that the common frog's diet changes according to the season when its prey is most abundant. In the summer, the common frog's diet mostly consists of adult [[Crane fly|crane flies]] and the larvae of butterflies and moths. To a slightly lesser extent, common frogs will feed on [[Woodlouse|woodlice]], arachnids, beetles, slugs, snails, and earthworms.<ref>{{cite journal |last1=Trakimas |first1=Giedrius |last2=Jardine |first2=Timothy D. |last3=Barisevičiūtė |first3=Rūta |last4=Garbaras |first4=Andrius |last5=Skipitytė |first5=Raminta |last6=Remeikis |first6=Vidmantas |date=6 July 2011 |title=Ontogenetic dietary shifts in European common frog (Rana temporaria) revealed by stable isotopes |journal=Hydrobiologia |volume=675 |issue=1 |pages=87 |doi=10.1007/s10750-011-0804-3 |bibcode=2011HyBio.675...87T |s2cid=39126267 |ref=Food2}}</ref><ref name="Stojanova-2008" /><ref>{{cite web | url=https://animaldiversity.org/accounts/Rana_temporaria/ | title=Rana temporaria | website=[[Animal Diversity Web]] }}</ref><ref>{{cite web | url=https://amphibiaweb.org/species/5168 | title=AmphibiaWeb – Rana temporaria }}</ref> In addition, common frogs will typically feed on bigger prey as they become larger. Therefore, newly developed common frogs are limited to smaller insect prey, whereas larger frogs are able to consume a wide range of insects. Common frogs will hide in damp places, such as in the water, during the day, and at night, they will begin searching for food.

== Reproduction and mating patterns==
[[File:DutchCommonFrogsCroackingRanaTemporaria.ogv|thumb|right|Choir of greyish males and a few brownish females still present in a small pond]]
During the spring the frog's [[pituitary gland]] is stimulated by changes in external factors, such as rainfall, day length and temperature, to produce hormones which, in turn, stimulate the production of sex cells – [[egg]]s in the females and [[sperm]] in the male. The male's nuptial pad also swells and becomes more heavily pigmented.<ref name="frog reproduction">{{cite web|url=http://www.frog-garden.com/frog-reproduction.html|title=Frog Reproduction|last=Anon|work=Frog-garden.com|access-date=23 March 2014|archive-date=21 January 2019|archive-url=https://web.archive.org/web/20190121083313/https://www.frog-garden.com/frog-reproduction.html|url-status=dead}}</ref> Common frogs breed in shallow, still, fresh water such as ponds, with spawning commencing sometime between late February and late June, but generally in April over the main part of their range.<ref name="Amphibia"/>

=== Competition among males ===
Like its close cousin, the moor frog (''R. arvalis''), ''R. Temporaria'' does not exhibit [[Territory (animal)|territoriality]], resulting in a lack of physical fighting among males. During the breeding season, male common frogs undergo a period of a few days (less than 10 days) during whichthey display rapid and frenzied breeding behavior,<ref name="Elmberg-1986">{{cite journal |last1=Elmberg |first1=Johan |date=1986 |title=Apparent lack of territoriality during the breeding season in a boreal population of common frogs Rana temporaria L |url=https://www.thebhs.org/publications/the-herpetological-journal/volume-1-number-2-june-1986/1129-09-apparent-lack-of-territoriality-during-the-breeding-season-in-a-boreal-population-of-common-frogs-rana-temporaria-l |journal=Herpetological Journal |volume=1 |issue=2 |pages=81–83 |language=en-gb |ref=breeding1}}</ref> during which the purpose of the male is to quickly find and mate with as many female frogs as possible. Males with higher mating success rates typically have longer thumbs than single males,<ref name="Ryser-1989">{{cite journal |last1=Ryser |first1=Jan |date=1 January 1989 |title=The breeding migration and mating system of a Swiss population of the common frog Rana temporaria |journal=Amphibia-Reptilia |volume=10 |issue=1 |pages=13–21 |doi=10.1163/156853889X00269 |ref=breeding2|doi-access=free }}</ref> which gives them  a better grip on females.

=== Mating interactions ===
About three years after birth, the common frog will return to its original birthplace and emit a [[mating call]]. Males will be the first to arrive at the pond and wait for females to enter. During this period of pre-female competition, the pond becomes significantly male-dominated, and there is a substantial degree of [[Male intrasexual competition|intrasexual competition]] taking place.<ref name="Ryser-1989" /> The shallower portion of the pond, which is more conducive to egg-laying, is more predominantly occupied by the larger males. However, once the females arrive, this territoriality quickly dissipates and male-female [[Amplexus|amplexed]] pairs are free to move anywhere in the pond. Additionally, once an amplexus is established, it is rare for single males to attempt to displace or "take over" the paired male.<ref name="Ryser-1989" />

It is also important to note the effect of size on the mating strategies of a male common frog. Smaller frogs are crowded out of the shallow areas of the pond during the pre-spawning period, a problem which they circumvent by searching for females on the land or in areas of the pond where they first arrive.<ref name="Elmberg-1986" /> Meanwhile, the larger frogs occupy the spawning site, where they encounter more amplexed pairs and therefore rely on their ability to displace amplexed males to secure a mate.<ref name="Elmberg-1986" /> However, the frequency of these takeovers is not consistent.

==Life cycle==
Clutch sizes of female common frogs range from a few hundred to 5,000 eggs. Many of these eggs form large aggregations that serve to thermoregulate and protect the developing embryo from potential predators. The aggregation of eggs raises the temperature of the embryo relative to the surrounding water, which is important because the rate of tadpole development is faster at higher temperatures.<ref name="Laugen-2003">{{cite journal |last1=Laugen |first1=A. T. |last2=Laurila |first2=A. |last3=Rasanen |first3=K. |last4=Merila |first4=J. |date=September 2003 |title=Latitudinal countergradient variation in the common frog (Rana temporaria) development rates – evidence for local adaptation |journal=Journal of Evolutionary Biology |volume=16 |issue=5 |pages=996–1005 |doi=10.1046/j.1420-9101.2003.00560.x |pmid=14635915 |s2cid=22444241 |ref=dev1|doi-access=free }}</ref> Additionally, the eggs are typically laid in the shallower regions of the pond to prevent hypoxia-induced fatality of the embryos.<ref name="Laugen-2003" />

It usually takes 2-3 weeks for the eggs to hatch. After that, the frog larvae group together in schools, where they help each other to feed on algae and larger plants, and to avoid predators.<ref name="Terhivuo-1988" /> By June and July, most tadpoles will have [[Metamorphosis|metamorphosized]], and the remaining time until winter is used to feed and grow larger.<ref name="Terhivuo-1988">{{cite journal |last1=Terhivuo |first1=Juhani |date=1988 |title=Phenology of spawning for the Common Frog (Rana temporaria L.) in Finland from 1846 to 1986 |url=http://www.jstor.org/stable/23734521 |journal=Annales Zoologici Fennici |volume=25 |issue=2 |pages=165–175 |jstor=23734521 |issn=0003-455X |ref=dev2}}</ref> Only the largest frogs will survive the winter, which places a large emphasis on rapid development until then. In fact, a common frog's rate of development correlates with temperature. In lower temperature regions, common frogs will hatch earlier and metamorphosize sooner than common frogs living in warmer climate regions.<ref name="Terhivuo-1988" /> Sexual maturity occurs only after three years, and common frogs will typically live between six and eight years.<ref name="Laugen-2003" />[[File:Junger Grasfrosch (Rana temporaria) in Buchenlaub im Naturpark Pfälzerwald.jpg|thumb|Common frog camouflaged in autumn leaves.]]

===Development in the presence of predators===
The presence of a predator in the early development of the tadpole affects its metamorphic traits. For example, it can lead to a longer larval period and a smaller size and mass at metamorphosis.<ref name="Vodrážková-2022" /> Once the predator is removed, the growth rate of the tadpole returns to, or even exceeds, baseline. This influence of predator threat is only significant during early tadpole development.<ref name="Vodrážková-2022">{{cite journal |last1=Vodrážková |first1=M. |last2=Šetlíková |first2=I. |last3=Navrátil |first3=J. |last4=Berec |first4=M. |date=12 May 2022 |title=Different time patterns of the presence of red-eared slider influence the ontogeny dynamics of common frog tadpoles |journal=Scientific Reports |volume=12 |issue=1 |pages=7876 |doi=10.1038/s41598-022-11561-6 |pmid=35552438 |pmc=9098440 |bibcode=2022NatSR..12.7876V |s2cid=248759763 |ref=devpred}}</ref>

One of the common frog's most pervasive predators is the red-eared slider (''[[Red-eared slider|''Trachemys scripta elegans'']]''), which is a very invasive species of turtle.

== Thermoregulation ==
As an [[ectotherm]], the common frog is highly dependent on temperature as it directly affects its [[metabolism]], development, reproduction, muscular strength, and respiration. As such, common frogs at medium and high elevations have developed a unique set of strategies to survive in cold climates. In fact, it is due to the common frog's ability to thermoregulate so effectively that the species has been able to become so widespread in a variety of environments and climates, living as far north as the [[Arctic Circle]] in [[Scandinavia]], which is further north than any other amphibian in the region.<ref name="Ludwig-2015" /> Contrary to ''[[Wood frog|''Lithobates sylvaticus'']]'' (wood frogs), common frogs do not have the ability to freeze protect themselves by increasing their levels of blood glucose to serve as a [[cryoprotectant]].<ref name="Ludwig-2015">{{cite journal |last1=Ludwig |first1=Gerda |last2=Sinsch |first2=Ulrich |last3=Pelster |first3=Bernd |date=1 April 2015 |title=Behavioural adaptations of Rana temporaria to cold climates |journal=Journal of Thermal Biology |volume=49-50 |pages=82–90 |doi=10.1016/j.jtherbio.2015.02.006 |pmid=25774030 |bibcode=2015JTBio..49...82L |ref=thermoreg}}</ref> As a result, common frogs must rely on behavioral thermoregulation by seeking out warm microhabitats (such as in the soil or between rocks) during wintertime. In addition, common frogs often hibernate in groups during the winter season in order to maintain body heat.<ref name="Ludwig-2015" />

== Social behavior ==
Similar to other [[Frog|anuran]] species (''[[American toad|Bufo americanus]]'' and ''[[Wood frog|Rana sylvatica]]''), ''Rana temporaria'' are able to naturally discriminate others of its kind. Post-embryonic interaction with conspecifics is not necessary to induce associative behavior for common frogs as an adult. Rather, once common frog tadpoles have reached a certain age, they gain a strong innate associative tendency.<ref>{{cite journal |last1=Griffiths |first1=R. A. |last2=Foster |first2=J. P. |date=August 1998 |title=The effect of social interactions on tadpole activity and growth in the British anuran amphibians ( Bufo bufo , B. calamita , and Rana temporaria ) |journal=Journal of Zoology |volume=245 |issue=4 |pages=431–437 |doi=10.1017/S0952836998008061}}</ref> ''Rana temporaria'' tend to aggregate as the result of environmental pressures, such as temperature or predators.<ref>{{cite journal |last1=Nicieza |first1=A. G. |date=December 1999 |title=Context-dependent aggregation in Common Frog Rana temporaria tadpoles: influence of developmental stage, predation risk and social environment: Context-dependent aggregation in frog tadpoles |journal=Functional Ecology |language=en |volume=13 |issue=6 |pages=852–858 |doi=10.1046/j.1365-2435.1999.00375.x|doi-access=free }}</ref>
[[File:Graureiher mit Grasfrosch Federsee Bad-Wuertt Guntram Deichsel 2013.jpg|thumb|[[Grey heron]] feeding on a common frog]]

==Predators==
Tadpoles are eaten by fish, [[Dytiscidae|diving beetles]], dragonfly larvae and birds. Adult frogs have numerous predators including [[storks]], [[birds of prey]], [[crow]]s, [[gull]]s, ducks, [[tern]]s, [[heron]]s, [[pine marten]]s, [[stoat]]s, [[weasel]]s, [[European polecat|polecats]], [[badger]]s, [[otter]]s and snakes.<ref name="Anon">{{cite web |last=Anon |title=Common frog: rana temporaria |url=http://www.snh.org.uk/pdfs/education/commonfrog.pdf |url-status=dead |archive-url=https://web.archive.org/web/20100215055419/http://www.snh.org.uk/pdfs/education/commonfrog.pdf |archive-date=15 February 2010 |access-date=10 November 2010 |work=All about... |publisher=Scottish National Heritage}}</ref> Some frogs are killed, but rarely eaten, by [[domestic cat]]s, and large numbers are killed on the roads by motor vehicles.<ref>[[RSPB]] '''Birds''' magazine Summer 2004, page 66</ref>

==Interactions with humans and livestock==
Common frogs have an important place in human ecology by controlling the insect populations. In particular, their consumption of [[mosquito]]s and other crop-damaging insects has been especially valuable. In addition, ''Rana temporaria'', due to their ecological pervasiveness and relative abundance, have become a common laboratory specimen.<ref name="Anon" />

==Farming==
''R. temporaria'' are [[frog raising|farmed]].<ref name="Ferrie-et-al-2014">{{cite conference |last1=Ferrie |first1=Gina M. |last2=Alford |first2=Vance C. |last3=Atkinson |first3=Jim |last4=Baitchman |first4=Eric |last5=Barber |first5=Diane |last6=Blaner |first6=William S. |last7=Crawshaw |first7=Graham |last8=Daneault |first8=Andy |last9=Dierenfeld |first9=Ellen |last10=Finke |first10=Mark |last11=Fleming |first11=Greg |last12=Gagliardo |first12=Ron |last13=Hoffman |first13=Eric A. |last14=Karasov |first14=William |last15=Klasing |first15=Kirk |last16=Koutsos |first16=Elizabeth |last17=Lankton |first17=Julia |last18=Lavin |first18=Shana R. |last19=Lentini |first19=Andrew |last20=Livingston |first20=Shannon |last21=Lock |first21=Brad |last22=Mason |first22=Tom |last23=McComb |first23=Alejandra |last24=Morris |first24=Cheryl |last25=Pessier |first25=Allan P. |last26=Olea-Popelka |first26=Francisco |last27=Probst |first27=Tom |last28=Rodriguez |first28=Carlos |last29=Schad |first29=Kristine |last30=Semmen |first30=Kent |last31=Sincage |first31=Jamie |last32=Stamper |first32=M. Andrew |last33=Steinmetz |first33=Jason |last34=Sullivan |first34=Kathleen |last35=Terrell |first35=Scott |last36=Wertan |first36=Nina |last37=Wheaton |first37=Catharine J. |last38=Wilson |first38=Brad |last39=Valdes |first39=Eduardo V. |title=Nutrition and health in amphibian husbandry |journal=[[Zoo Biology]] |publisher=[[Wiley Periodicals]] |volume=33 |issue=6 |date=2014-10-08 |issn=0733-3188 |doi=10.1002/zoo.21180 |pages=485–501 |conference=Veterinary Medicine, Husbandry, Nutrition, Science, and Research Working Groups of the Ex Situ Amphibian Medicine and Nutrition Workshop (February 2013) |s2cid=17636001 |pmid=25296396 |pmc=4685711}} [[NIH Manuscript Submission|NIHMSID]] 743535.</ref> Miles ''et al.'' 2004 provide improved ingredients for manufacturers of [[food pellet|pellet food]] for farmed common frogs.<ref name="Ferrie-et-al-2014" />

Due to the spread of diseases such as ranavirus, the UK-based amphibian charity [[Froglife]] advised the public to avoid moving frogspawn, tadpoles or frogs from one pond to another, even if they are nearby.<ref>{{Cite web |title=Spawn & tadpoles: in my garden |url=https://www.froglife.org/info-advice/frequently-asked-questions/spawn-tadpoles-larvae/ |access-date=2022-05-18 |website=froglife.org}}</ref> It has also been recommended not to place goldfish or exotic frog species in outdoor ponds as this could have a negative effect on the frog population.

==References==<!-- Molecular Phylogenetics and Evolution 46 (2008) 49–60 -->
{{Reflist}}

==External links==
{{Commons category|Rana temporaria}}
{{Wikispecies|Rana temporaria}}
*[http://www.herp.it/ Amphibians of Europe]
*[http://www.frogswatch.com/ FrogsWatch.com Web page developed around photographs of the common frog taken in the same suburban garden over a period of 10 years. ]

{{portalbar|Frogs}}
{{Rana (genus)}}
{{Taxonbar|from=Q27465}}
{{Authority control}}

[[Category:Rana (genus)]]
[[Category:Amphibians of Europe]]
[[Category:Arctic land animals|Frog, Common]]
[[Category:Animal models]]
[[Category:Fauna of Finland]]
[[Category:Articles containing video clips]]
[[Category:Amphibians described in 1758]]
[[Category:Taxa named by Carl Linnaeus]]
[[Category:Habitats Directive species]]