{{short description|Species of amphibian}} {{speciesbox | image = Vodnice posvátná zoo praha 2.jpg | image_caption = An individual feeding on a worm | status = EN | status_system = IUCN3.1 | status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=IUCN SSC Amphibian Specialist Group |date=2020 |title=''Telmatobius culeus'' |volume=2020 |article-number=e.T57334A178948447 |doi=10.2305/IUCN.UK.2020-2.RLTS.T57334A178948447.en |access-date=19 November 2021}}</ref> | status2 = CITES_A1 | status2_system = CITES | status2_ref = <ref name=CITES>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php| access-date=2022-01-14 |website=cites.org}}</ref> | taxon = Telmatobius culeus | authority = (Garman, 1876) | synonyms = *''Telmatobius albiventris'' *''Telmatobius crawfordi'' }}
'''''Telmatobius culeus''''', commonly known as the '''Titicaca water frog''' or '''Lake Titicaca frog''',<ref name="iucn status 19 November 2021"/> is a medium-large to very large and endangered species of frog in the family Telmatobiidae.<ref name=Threatened>{{cite book | editor1=Stuart, S. | editor2=M. Hoffmann | editor3=J. Chanson | editor4=N. Cox | editor5=R. Berridge | editor6=P. Ramani | editor7=B. Young | year=2008 | title=Threatened Amphibians of the World | pages=101, 410–419 | publisher=Lynx Edicions | isbn=978-84-96553-41-5 }}</ref> It is entirely aquatic and found only in the Lake Titicaca basin, including rivers that flow into it and smaller connected lakes like Arapa, Lagunillas and Saracocha, in the Andean highlands of Bolivia and Peru.<ref name=amphibiaweb>{{Cite web | author1=Lee, D. | author2=A.T. Chang | date=17 January 2019 | title=Telmatobius culeus | url=https://amphibiaweb.org/species/2695 | editor1=M.S. Koo | editor2=K. Whittaker | publisher=AmphibiaWeb, University of California, Berkeley | access-date=23 January 2020 }}</ref><ref name=Benavides2002>{{cite journal | author1=Benavides, E. | author2=J.C. Ortiz | author3=J.W. Sites, JR. | year=2002 | title=Species boundaries among the ''Telmatobius'' (Anura: Leptodactylidae) of the Lake Titicaca basin: Allozyme and morphological evidence | journal=Herpetologica | volume=58 | issue=1 | pages=31–55 | doi=10.1655/0018-0831(2002)058[0031:SBATTA]2.0.CO;2 | s2cid=33007774 }}</ref><ref name=Vellard1992>{{cite book | author=Vellard, J. | year=1992 | chapter=The Amphibia | pages=449–557 | editor1=C. Dejoux | editor2=A. Iltis | title=Lake Titicaca: a synthesis of limnological knowledge | publisher=Kluwer Academic Publishers | isbn=0-7923-1663-0 }}</ref> In reference to its loose skin, it is sometimes jokingly referred to as the '''Titicaca scrotum frog'''.<ref name=Gill2013>{{cite news|author=Gill, V. | date=12 September 2013 | title=Blobfish wins ugliest animal vote | url=https://www.bbc.co.uk/news/science-environment-24040130 | work=BBC News | access-date=12 September 2013 }}</ref>
It is closely related to the more widespread and semiaquatic marbled water frog (''T. marmoratus''),<ref name=Victoriano2015>{{cite journal |last1=Victoriano |first1=Pedro F. |last2=Muñoz-Mendoza |first2=Carla |last3=Sáez |first3=Paola A. |last4=Salinas |first4=Hugo F. |last5=Muñoz-Ramírez |first5=Carlos |last6=Sallaberry |first6=Michel |last7=Fibla |first7=Pablo |last8=Méndez |first8=Marco A. |title=Evolution and conservation on top of the world: Phylogeography of the marbled water frog (''Telmatobius marmoratus'' species complex; Anura, Telmatobiidae) in protected areas of Chile |journal=Journal of Heredity |date=2015 |volume=106 |issue=S1 |pages=546–559 |doi=10.1093/jhered/esv039|pmid=26245789 }}</ref><ref>{{cite journal |last1=De la Riva |first1=Ignacio |last2=García-París |first2=Mario |last3=Parra-Olea |first3=Gabriela |title=Systematics of Bolivian frogs of the genus ''Telmatobius'' (Anura, Ceratophryidae) based on mtDNA sequences |journal=Systematics and Biodiversity |date=2010 |volume=8 |issue=1 |pages=49–61 |doi=10.1080/14772000903526454|bibcode=2010SyBio...8...49D }}</ref> which also occurs in shallow, coastal parts of Lake Titicaca,<ref>{{cite journal |last1=Cossel |first1=J. |last2=Lindquist |first2=E. |last3=Craig |first3=H. |last4=Luthman |first4=K. |title=Pathogenic fungus ''Batrachochytrium dendrobatidis'' in marbled water frog ''Telmatobius marmoratus'': first record from Lake Titicaca, Bolivia |journal=Diseases of Aquatic Organisms |date=2014 |volume=112 |issue=1 |pages=83–87 |doi=10.3354/dao02778|doi-access=free |pmid=25392045 }}</ref> but lacks the excessive skin and it is generally smaller (although overlapping in size with some forms of the Titicaca water frog).<ref name=Benavides2002/>
==Appearance== ===Size=== In the late 1960s, an expedition led by Jacques Cousteau reported Titicaca water frogs up to {{cvt|2|ft|cm|-1|order=flip}} in outstretched length and {{cvt|1|kg|lb}} in weight,<ref>{{cite news | author=McDowell, E. | date=29 November 1987 | title=The Lake Atop Bolivia | url=https://www.nytimes.com/1987/11/29/travel/the-lake-atop-bolivia.html | work=New York Times | access-date=18 January 2020 }}</ref><ref>{{cite book | editor1=Quinn, J.A. | editor2=S.L. Woodward | year=2015 | title=Earth's Landscape: An Encyclopedia of the World's Geographic Features | page=404 | publisher=Bloomsbury Academic | isbn=978-1-61069-445-2 }}</ref><ref name=Cousteau1969>{{Cite episode | title=The Legend of Lake Titicaca | series=The Undersea World of Jacques Cousteau | author1=Cousteau, J. | author2=A. Landsburg | date=24 April 1969 | number=7 }}</ref> making these some of the largest exclusively aquatic frogs in the world (the exclusively aquatic Lake Junin frog can grow larger, as can the helmeted water toad and African goliath frog that sometimes can be seen on land).<ref name=Halliday>{{cite book | author=Halliday, T. | year=2016 | title=The Book of Frogs: A Life-Size Guide to Six Hundred Species from around the World | pages=89, 258–259, 527 | publisher=University Of Chicago Press | isbn=978-0-226-18465-4 }}</ref> The snout–vent length of the Titicaca water frog is up to {{cvt|20|cm|in|0}},<ref name=BerlinZoo>{{cite web | title=Titicaca water frogs | work=Zoo Berlin | date=20 November 2017 | url=https://www.zoo-berlin.de/en/species-conservation/worldwide/titicaca-water-frogs | publisher=Berlin Zoo | access-date=4 January 2020 | archive-date=30 July 2020 | archive-url=https://web.archive.org/web/20200730234416/https://www.zoo-berlin.de/en/species-conservation/worldwide/titicaca-water-frogs }}</ref><ref name=Mendoza2019>{{cite report |author=Mantilla Mendoza, B. |author2=Dina Pari Quispe |author3=Manuel Mamani Flores | year=2023 | title=Reproducción de la rana gigante (''Telmatobius culeus'', Garman 1875) del lago Titicaca en ambientes controlados, Puno | publisher=Universidad Nacional Autónoma de Tayacaja Daniel Hernández Morillo (UNAT) |url=https://fondoeditorial.unat.edu.pe/index.php/EdiUnat/catalog/view/16/17/51 }}</ref> and the hindlegs about twice as long.<ref name=Cousteau1969/> [[File:Vodnice posvátná zoo praha 1.jpg|left|thumb|Individual from the captive breeding program at Prague Zoo]] Most individuals do not reach such sizes, but are still big frogs. Titicaca water frogs of the largest and typical form, upon which the species was first described, usually have a snout–to–vent length of {{cvt|7.5|to(-)|17|cm|in}} and weigh less than {{cvt|0.4|kg|lb|1}}.<ref name=Benavides2002/><ref name=Halliday/><ref name=Mendoza2019/> This typical form tends to inhabit relatively deep water in eastern Lake Titicaca, but a minority of the individuals in the Coata River (which flows into far western Lake Titicaca) are similar.<ref name=Benavides2002/><ref name=Vellard1992/> Several other forms are found at shallower depths in Lake Titicaca, in smaller lakes that are part of the same basin, and in rivers and streams that flow into Titicaca. These tend to be smaller in size with a snout–to–vent length of {{cvt|4|to(-)|8.9|cm|in}} and historically they were recognized as separate species (''T. albiventris'' and ''T. crawfordi''), but there are extensive individual variations (sometimes even at a single location), no clear limits between the forms (they intergrade) and taxonomic reviews have found that all are variants of the Titicaca water frog.<ref name=Benavides2002/><ref name=Vellard1992/> Females generally reach maturity at a slightly larger size than males, they average larger and they also have a larger maximum size than males.<ref name=Mendoza2019/><ref name=Saravia2018>{{cite journal | author1=Muñoz-Saravia, A. | author2=G. Callapa | author3=G.P.J. Janssens | year=2018 | title=Temperature exposure and possible thermoregulation strategies in the Titicaca water frog ''Telmatobius culeus'', a fully aquatic frog of the High Andes | journal=Endangered Species Research | volume=37 | pages=91–103 | doi=10.3354/esr00904 | doi-access=free | hdl=1854/LU-8618660 | hdl-access=free }}</ref><ref name=BolAmpIn>{{cite news | title=Telmatobius culeus | url=http://bolivianamphibianinitiative.org/telmatobius-culeus/ | publisher=Bolivian Amphibian Initiative | archive-url=https://web.archive.org/web/20171027072702/http://bolivianamphibianinitiative.org/telmatobius-culeus/ | archive-date=27 October 2017 }}</ref>
===Morphology and color=== [[File:Telmatobius culeus.jpg|thumb|Illustration by Samuel Garman (1876) showing the typical form of the species]]In addition to total size, the various forms of the Titicaca water frog differ in the relative size of the dorsal shield (a hard structure on the back), relative width of the head and other morphological features, with most bays in Lake Titicaca having their own type.<ref name=Benavides2002/><ref name=Vellard1992/>
Compared to similar-sized frogs, the lungs of the Titicaca water frog only are about one-third the size. Instead it has excessive amounts of skin to help the frog respire in the cold water in which it lives.<ref name=amphibiaweb/><ref name=Hutchison1976>{{cite journal | author1=Hutchison, V.H. | author2=H.B. Haines | author3=G. Engbretson | year=1976 | title=Aquatic life at high altitude: Respiratory adaptations in the Lake Titicaca frog, ''Telmatobius culeus'' | journal=Respiration Physiology | volume=27 | issue=1 | pages=115–129 | doi=10.1016/0034-5687(76)90022-0 | pmid=9678 }}</ref><ref name=Hutchison2008>{{cite journal | author=Hutchison, V.H. | year=2008 | title=Amphibians: Lungs' Lift Lost | journal=Current Biology | volume=18 | issue=19| pages=R392–R393 | doi=10.1016/j.cub.2008.03.006 | pmid=18460323 | doi-access=free | bibcode=2008CBio...18.R392H }}</ref> The baggy skin is particularly distinct in large individuals.<ref name=Knoll2017>{{cite thesis | author=Knoll, S. | year=2017 | title=Nutrition of the Titicaca water frog (''Telmatobius culeus'') |type=Master thesis | publisher=Ghent University |url=https://libstore.ugent.be/fulltxt/RUG01/002/509/181/RUG01-002509181_2018_0001_AC.pdf }}</ref> In living individuals the skin folds are swollen with fluids, but if deflated the frog is actually relatively thin.<ref name=Vellard1992/>
The color is highly variable, but generally gray, brown or greenish above, and paler below. There are often some spots, which can form a marbled pattern.<ref name=BolAmpIn/><ref name=Knoll2017/> Animals in coastal southernmost Lake Titicaca typically have striped thighs and relatively bright orange underparts.<ref name=Vellard1992/> If teased, Titicaca water frogs can secrete a sticky whitish fluid from their skin in defense.<ref name=Allen1922>{{cite journal | author=Allen, W.R. | year=1922 | title=Notes on the Andean frog, ''Telmatobius culeus'' (Garman) | journal=Copeia | volume=108 | issue=108 | pages=52–54 | doi=10.2307/1436304 | jstor=1436304 }}</ref>
==Habitat and ecology== Titicaca water frogs live exclusively in lakes and rivers in the Lake Titicaca basin.<ref name=Vellard1992/><ref name=Knoll2017/> Adults of the typical form generally live deeper than {{cvt|10|m|ft}} in Lake Titicaca itself,<ref name=Benavides2002/> but the maximum limit is unknown.<ref name=LiveS2016/> While exploring this lake in a mini submarine, Jacques Cousteau filmed individuals and their prints in the bottom silt at {{cvt|120|m|ft|-2}}, which is the record depth for any species of frog.<ref name=Cousteau1969/><ref name=Knoll2017/> The other forms of the Titicaca water frog are found at no more than {{cvt|10|m|ft}}.<ref name=Benavides2002/> A study that surveyed depths from the shore to {{cvt|7|m|ft}} near Isla del Sol found that adults were most common at {{cvt|1.5-3|m|ft|0}}.<ref name=Saravia2018/> In general, Titicaca water frogs prefer a mixed bottom; either a muddy or sandy bottom with some rocks, or with plenty of aquatic plants and some rocks.<ref name=Saravia2018/><ref name=Knoll2017/>
===Temperature=== The Titicaca water frog spends its entire life in water that typically is {{cvt|8|-|17.5|C|F|round=0.5}}, with the average annual temperature being near the middle and the minor seasonal variations being matched or even exceeded by the daily variations.<ref name=Mendoza2019/><ref name=Saravia2018/> The frogs can regulate their own temperature by moving between different microhabitats with slightly different water temperatures and adults will sometimes position themselves on top of underwater rocks to bask in the sun that penetrate the lake's clear water.<ref name=Saravia2018/>
===Respiration=== The water in which it lives generally is very rich in oxygen, but limited by the low atmospheric pressure at the high altitude,<ref name=amphibiaweb/><ref name=Hutchison1976/><ref name=Hutchison2008/> from about {{cvt|3800|m|ft}} at Lake Titicaca to at least {{cvt|4250|m|ft|-3}} in associated river and smaller lakes.<ref name=Vellard1992/> It respires by its skin, which absorbs oxygen, functioning in a manner that is comparable to gills.<ref name=Hutchison1976/><ref name=Hutchison2008/><ref name=LiveS2016>{{cite news | last=Pappas | first=S. | title=Dying Breed? Zoo Toils to Save Strange 'Scrotum Frog' | url=http://www.livescience.com/54567-zoo-tries-to-save-strange-titicaca-frogs.html/|publisher=Live Science | access-date=9 February 2017 | date=27 April 2016}}</ref> It sometimes performs "push-ups" or "bobs" up–and–down to allow more water to pass by its large skin folds. The skin is very rich in blood vessels that extend to its outermost layer. Of all frogs, it has the lowest relative red blood cell volume, but the highest count (i.e., many but small red blood cells) and with a high oxygen capacity. The frog mainly stays near the bottom and it has never been observed to surface in the wild, but captive studies indicate that it may surface to breathe using its diminutive lungs if the water is poorly oxygenated.<ref name=amphibiaweb/><ref name=Hutchison1976/><ref name=Hutchison2008/>
==Behavior== ===Social behavior and breeding=== Although a good swimmer, several individuals can often be seen laying inactively next to each other on the bottom.<ref name=Vellard1992/> Titicaca water frogs tend to be most active during the night.<ref name=Watson2017b>{{cite journal | author1=Watson, A.S. | author2=A.L. Fitzgerald | author3=O.J. Damián Baldeón | author4=R.K. Elía | year=2017 | title=Habitat characterization, occupancy and detection probability of the Endangered and endemic Junín giant frog ''Telmatobius macrostomus'' | journal=Endangered Species Research | volume=32 | pages=429–436 | doi=10.3354/esr00821 | doi-access=free }}<!-- ref mainly about T. macrostomus but also has a bit about T. culeus --></ref>
The Titicaca water frog breeds year-round in shallow coastal water where the female lays about 80 to 500 eggs.<ref name=amphibiaweb/><ref name=Knoll2017/> Amplexus lasts one to three days.<ref name=Mendoza2019/> The "nest" site is typically guarded by the male until the eggs hatch into tadpoles,<ref name=Knoll2017/> which happens after about one to two weeks.<ref name=Mendoza2019/><ref name=Perez1998>{{citation | author=Pérez, M.B. | year=1998 | title=Dieta y ciclo gametogénico anual de ''Telmatobius culeus'' (Anura, Leptodactylidae) en el Lago Titicaca (Huiñaimarca) | publisher=Higher University of San Andrés }}</ref> The tadpole stage lasts for a couple of months to a year.<ref name=Knoll2017/> The tadpoles and young froglets stay in shallows, only moving to deeper water when reaching adulthood.<ref name=Saravia2018/> Maturity is typically reached when about three years old.<ref name=Mendoza2019/>
===Feeding=== [[File:Telmatobius culeus VA.jpg|thumb|At the Vancouver Aquarium]] The Titicaca water frog mostly feeds on amphipods (especially ''Hyalella'') and snails (especially ''Heleobia'' and ''Biomphalaria''),<ref name=Saravia2018/> but other food items are insects and tadpoles.<ref name=amphibiaweb/> Adults also regularly eat fish (primarily ''Orestias'', up to at least {{cvt|4|in|cm|order=flip|disp=sqbr}} long) and cannibalism where large frogs eat small individuals has been recorded.<ref name=Knoll2017/><ref name=Allen1922/><ref>{{cite thesis | author=Muñoz Saravia, A. | year=2018 | title=Foraging strategies and ecology of Titicaca water frog (''Telmatobius culeus'') |type=PhD thesis | publisher=Ghent University |hdl=1854/LU-8577989 |url=https://biblio.ugent.be/publication/8577989 }}</ref> It has an extremely low metabolic rate; below that of all other frogs and among amphibians it is only higher than that of a few salamanders.<ref name=amphibiaweb/><ref name=Knoll2017/><ref name=Hutchison1976/>
In captivity, the tadpoles will feed on a range of tiny animals, such as copepods, water fleas, small worms and aquatic insect larvae.<ref name=Mendoza2019/>
===Call and hearing=== Similar to at least some other ''Telmatobius'' species, male Titicaca water frogs will call underwater when near the shore. The simple and repeated call can only be detected with a submerged microphone from a relatively short distance. The function is not clear, but calling primarily occurs during the night and it is likely related to attracting females, courtship or aggression.<ref name=Brunetti2017>{{cite journal | author1=Brunetti, A.E. | author2=A. Muñoz Saravia | author3=J.S. Barrionuevo | author4=S. Reichle | year=2017 | title=Silent sounds in the Andes: underwater vocalizations of three frog species with reduced tympanic middle ears (Anura: Telmatobiidae: ''Telmatobius'') | journal=Canadian Journal of Zoology | volume=95 | issue=5 | pages=335–343 | doi=10.1139/cjz-2016-0177 | bibcode=2017CaJZ...95..335B | hdl=11336/49168 | hdl-access=free }}</ref>
The ears are greatly reduced and several of the structures, including the tympanic membrane and the Eustachian tubes, are absent. How the Titicaca water frog hears is unconfirmed, but it probably involves the lungs (as known from some other frogs).<ref name=Brunetti2017/>
==Conservation status and threats== The Titicaca water frog has declined drastically, leading the IUCN to rank it as endangered.<ref name="iucn status 19 November 2021" />
It was once common, with a survey in the late 1960s by Jacques Cousteau and colleagues counting 200 individuals in an only {{convert|1|acre|ha|1}} plot of the huge lake.<ref name=Cousteau1969/> Although not directly comparable, a survey in 2017 of three {{cvt|100|x|2|m|ft|0}} transects at 38 locations only detected a total of 45 Titicaca water frogs at 6 of the locations (none at the remaining).<ref name=Rodrigo2019>{{cite journal | author1=Ramos Rodrigo, T.E. | author2=J.A. Quispe Coila | author3=R.K. Elias Piperis | year=2019 | title=Evaluación de la abundancia relativa de ''Telmatobius culeus'' en la zona litoral del lago Titicaca, Perú | journal= Revista Peruana de Biología| volume=26 | issue=4 | pages=475–480 | doi=10.15381/rpb.v26i4.17216 | doi-access=free }}</ref> It is estimated that it declined by more than 80% in just 15 years, from 1990 to 2004, equalling three Titicaca water frog generations.<ref name="iucn status 19 November 2021" /><ref name=amphibiaweb/><ref name=McKittrick2018>{{cite news|author=McKittrick, E. | year=2018 | title=Saving the Scrotum Frog | url=https://www.earthisland.org/journal/index.php/magazine/entry/saving-the-scrotum-frog/ | publisher=Earth Island Journal | access-date=22 January 2020 }}</ref> Several other species in the genus ''Telmatobius'' are facing similar risks.<ref name=Threatened/>
The causes of the precarious status of the Titicaca water frog are over-collecting for human consumption, pollution and introduced trout, and it may also be threatened by disease.<ref name="iucn status 19 November 2021" /><ref name=Threatened/> {{Citation needed span|Additionally, the Titicaca grebe, which are flightless birds that reside in the local area of Titicaca lake, have been targeting the animal. These birds have a Papillae that reacts positively to the skin of the frog.|date=January 2026}}
===Capture for food=== The species is consumed as a traditional food or blended drink known as frog juice, and as traditional medicine that is claimed to be an aphrodisiac, and treat infertility, tuberculosis, anemia, asthma, osteoporosis and fever, but this is entirely unsupported by evidence.<ref name=AmphibianArk>{{cite web | title=Telmatobius culeus | url=http://www.amphibianark.org/telmatobius-culeus/ | publisher=Amphibian Ark | access-date=20 January 2020 }}</ref><ref name=Fobar2019>{{cite web | author=Fobar, R. | date=19 April 2019 | title=How poachers of this rare frog became its protectors | url=https://www.nationalgeographic.com/animals/2019/04/former-peruvian-frog-poachers-help-protect-lake-titicaca-scrotum-frog/ | archive-url=https://web.archive.org/web/20190420003355/https://www.nationalgeographic.com/animals/2019/04/former-peruvian-frog-poachers-help-protect-lake-titicaca-scrotum-frog/ | archive-date=April 20, 2019 | publisher=National Geographic | access-date=20 January 2020 }}</ref> Dishes with Titicaca water frogs are also sold by some local restaurants as a novelty to tourists.<ref name=McKittrick2018/>
On a month-long expedition to Lake Titicaca 100 years ago, this frog was not seen in any of the markets in the region, no locals were seen hunting for it and when asked locals said they considered it inedible.<ref name=Allen1922/> Whether this reporting was incomplete or there has been a significant change is unclear, but by the 2000s tens of thousands were caught for food and traditional medicine each year,<ref name=CITESBolivia2016>{{cite web| title=Additional information on international trade Telmatobius culeus | url=https://cites.org/sites/default/files/eng/cop/17/InfDocs/E-CoP17-Inf-71.pdf | year=2016 | publisher=CITES | access-date=20 January 2020 }}</ref> and even though now illegal the trade has to some extent continued.<ref name=Fobar2019/><ref name=CITESPeru2019>{{cite web| title=Conservation of the Titicaca water frog (''Telmatobius culeus'') | url=https://cites.org/sites/default/files/eng/cop/18/doc/E-CoP18-087.pdf | year=2019 | publisher=CITES | access-date=20 January 2020 }}</ref> Smaller numbers have been exported to other countries as food, for frog leather (skin) and the pet trade.<ref name=CITESBolivia2016/>
=== Pollution and mass deaths === Pollution from mining, agriculture and human waste has become a serious problem in the range of the Titicaca water frog.<ref name="iucn status 19 November 2021" /><ref name=Threatened/> Breathing through their skin, Titicaca water frogs easily absorb chemicals from the water. Additionally, nutrient-rich pollution from agriculture can cause algae blooms where oxygen levels plummet, asphyxiating the fully aquatic frog.<ref name=McKittrick2018/>
Historically, smaller mass deaths occasionally occurred in this species, but they are now fairly common and since 2015 there have also been large mass deaths.<ref name=Fobar2019/><ref name=BolivianAmphibianInitiative>{{cite news|title=Rescuing Titicaca Water Frog | url=http://bolivianamphibianinitiative.org/titicaca-water-frog-project/ | publisher=Bolivian Amphibian Initiative | archive-url=https://web.archive.org/web/20170805172233/http://bolivianamphibianinitiative.org/titicaca-water-frog-project/ | archive-date=5 August 2017 }}</ref> In April 2015, thousands of dead Titicaca water frogs were found in Bolivia on the shore of Lake Titicaca,<ref name=StiftungArtenschutz>{{citation | title=Titicaca water frog | url=http://www.stiftung-artenschutz.de/projects/titicaca-water-frog/ | publisher=Stiftung Artenschutz | archive-url=https://web.archive.org/web/20180620014524/https://www.stiftung-artenschutz.de/projects/titicaca-water-frog/ | archive-date=20 June 2018 }}</ref> and in October 2016 an estimated 10,000 were found dead in the Coata River (a Lake Titicaca tributary). At least in the latter case, scientists believe pollution killed the frogs.<ref name="Howard">{{cite news| last1=Howard | first1=Brian Clark | title=10,000 'Scrotum Frogs' Die Mysteriously in Lake Titicaca|url=http://news.nationalgeographic.com/2016/10/scrotum-frogs-lake-titicaca-water-frogs-mass-death-peru-bolivia-pollution/ |archive-url=https://web.archive.org/web/20161019173415/http://news.nationalgeographic.com/2016/10/scrotum-frogs-lake-titicaca-water-frogs-mass-death-peru-bolivia-pollution/ |archive-date=October 19, 2016 | access-date=19 October 2016 | publisher=National Geographic | date=19 Oct 2016}}</ref><ref name="Collyns">{{cite news | last1=Collyns | first1=Dan | title=Scientists investigate death of 10,000 endangered 'scrotum' frogs in Peru | url=https://www.theguardian.com/environment/2016/oct/19/scientists-investigate-death-of-10000-endangered-scrotum-frogs-in-peru | access-date=19 October 2016 | work=The Guardian | date=19 Oct 2016}}</ref> This is also supported by the timing of the mass deaths, which mostly occur in the rainy season where pollution likely is washed into the lake from the surroundings.<ref name=Fobar2019/>
Die-offs possibly are reversible. It has been observed that small Titicaca water frogs may appear in the vicinity of an affected area later, possibly recolonizing it.<ref name=McKittrick2018/>
===Introduced trout=== The introduced, non-native rainbow trout likely feed on tadpoles of the Titicaca water frog, the frogs are caught as bycatch in fishing nets set for trout, and coastal pens for farming trout overlap with the frog's breeding habitat and may impact it.<ref name="iucn status 19 November 2021" /><ref name=McKittrick2018/> Lake Saracocha was home to Titicaca water frogs of the "''albiventris''" form, but they have not been found in later surveys and it is suspected that introduced trout were implicated in their apparent disappearance from this location.<ref name=Vellard1992/>
Rainbow trout was introduced on a US initiative from their original North American range to Lake Titicaca in 1941–42 to aid the local fisheries that had relied on the smaller native fish.<ref name=Indelicato2015/><ref name=Lauzanne1992>{{cite book | author=Lauzanne, L. | year=1992 | chapter=Fish Fauna | pages=405–448 | editor1=C. Dejoux | editor2=A. Iltis | title=Lake Titicaca: a synthesis of limnological knowledge | publisher=Kluwer Academic Publishers | isbn=0-7923-1663-0 }}</ref> The fast-growing and relatively large non-native fish (trout and Argentinian silverside) are now the most important species in local fisheries, far exceeding the fisheries for the smaller natives (''Orestias'' and ''Trichomycterus'').<ref name=Indelicato2015/><ref name=Lauzanne1992/> Because of the economic importance, these fisheries, along with trout farming, are supported by the local governments, making it unlikely that they would support any initiatives to reduce or even remove the trout from the region.<ref name=McKittrick2018/>
===Disease=== ''Batrachochytrium dendrobatidis'', a fungus that causes the disease chytridiomycosis in frogs, has been present in the Andes for a long time. Although first definitely confirmed in Lake Titicaca in a study in 2012–2016,<ref name=Berenguel2016>{{cite journal | author1=Berenguel, R.A. | author2=R.K. Elias | author3=T.J. Weaver | author4=R.P. Reading | year=2016 | title=Chytrid fungus, ''Batrachochytrium dendrobatidis'', in wild populations of the Lake Titicaca frog, ''Telmatobius culeus'', in Peru | journal=Journal of Wildlife Diseases | volume=52 | issue=4 | pages=973–975 | doi=10.7589/2016-01-007 | pmid=27525594 | s2cid=46881923 }}</ref> a later study of museum specimens found it in several old Titicaca water frogs, one of them collected in 1863, which is the oldest known case of the fungus in the world.<ref name=Burrowes2017>{{cite journal | author1=Burrowes, Patricia A. | author2=De la Riva, Ignacio | year=2017 | title=Unraveling the historical prevalence of the invasive chytrid fungus in the Bolivian Andes: implications in recent amphibian declines | journal=Biological Invasions | volume=19 | issue=6 | pages=1781–1794 | doi=10.1007/s10530-017-1390-8 | bibcode=2017BiInv..19.1781B | s2cid=23460986 }}</ref> However, this appears to involve a much less virulent form and widespread deaths of frogs in the highlands of Bolivia and Peru only began much later, in the 1990s, likely coinciding with the spread of a far more lethal form of the fungus.<ref name=Burrowes2017/> The rapid declines, often closely linked to chytridiomycosis, have affected several of its relatives (some of them likely now extinct),<ref name=Threatened/><ref name=Mayer2019>{{cite web | author=Mayer, L.R. | date=14 February 2019 | title=A Tale Of Two Frogs (And Some Of The Biologists Who Love Them) | url=https://www.globalwildlife.org/blog/a-tale-of-two-frogs-and-some-of-the-biologists-who-love-them/ | publisher=Global Wildlife Conservation | access-date=24 January 2020 }}</ref> but the disease does not appear to have seriously affected the Titicaca water frog.<ref name=Saravia2018/><ref name=Berenguel2016/> This may change with global warming if the water it lives in surpasses {{cvt|17|C|F}} for longer periods, which is the optimum temperature for the disease (it is lethal to many frog species at {{cvt|17-25|C|F|disp=sqbr}}),<ref name=Saravia2018/><ref name=Berenguel2016/> or with increasing pollution, making the Titicaca water frogs more vulnerable to infection.<ref name=LiveS2016/> Another factor that may afford some protection to this frog is the slightly basic water (generally pH ≥7.5) of Lake Titicaca, as the fungus has the best growth rates in neutral or slightly acidic conditions (pH 6–7).<ref name=Saravia2018/><ref name=Berenguel2016/>
==Conservation measures== [[File:Lake Titicaca frogs in Denver Zoo's Tropical Discovery, Aug 2018.jpg|thumb|A group at Denver Zoo, which initiated the captive breeding program for this frog outside its native South America and supported the original program in Peru]]
The Titicaca water frog is regarded as one of the flagship species of Lake Titicaca,<ref name=CITESPeru2019/> and in 2019 Peru issued a 1 sol coin with an illustration of this frog as part of an endangered wildlife series.<ref>{{cite web | author=Starck, J. | date=28 November 2019 | title=Peru completes circulating commemorative wildlife series | url=https://www.coinworld.com/news/precious-metals/peru-completes-circulating-commemorative-wildlife-series | publisher=Coin World | access-date=20 January 2020 }}</ref>
In 2013, it was one of the contenders for "ugliest animal", a humorous public vote arranged by the Ugly Animal Preservation Society, an organisation that attempts to draw attention to threatened species that lack the cuteness factor.<ref name=Gill2013/>
===Protection=== In Peru, trade outside its native range at Lake Titicaca has been illegal for decades,<ref name=AmphibianArk/> and in 2014 it was afforded full protection in the country, making it illegal to catch the species.<ref name=CITESPeru2019/> The Peruvian authorities have seized thousands of Titicaca water frogs that were illegally traded within the country.<ref name=AmphibianArk/><ref name=Fobar2019/> In 2016–2017, it was legally protected from hunting in Bolivia.<ref name=CITESPeru2019/> Since 2016, commercial international trade has been prohibited because it is included on CITES Appendix I.<ref name=CITESPeru2019/><ref name=CITES/>
Reserves where the frog occurs have been established,<ref name=CITESPeru2019/> and Lake Titicaca is recognized as a Ramsar site, but the protection provided by reserves in this region is often very limited.<ref name=McKittrick2018/>
===Projects=== Bolivia and Peru have agreed to work together to resolve the environmental problems of Lake Titicaca, but corruption and the risk of local civil unrest might cause problems for the implementation of this.<ref name=Indelicato2015>{{cite web | author=Bloudoff-Indelicato, M. | date=9 December 2015 | title=What Are North American Trout Doing in Lake Titicaca? | url=https://www.smithsonianmag.com/science-nature/what-are-north-american-trout-doing-lake-titicaca-180957472/ | publisher=Smithsonian Magazine | access-date=20 January 2020 }}</ref> In 2016, the two countries pledged to use 500 million US dollars on it, including new water treatment facilities; otherwise waste water has been led directly into the lake.<ref name=amphibiaweb/><ref name=Fobar2019/>[[File:Titicaca Frog - Singapore Zoo.png|thumb|An individual pictured at Singapore Zoo]]
Conservation projects specifically aimed at the Titicaca water frog have been initiated, some of them in cooperation between Bolivia and Peru, including population monitoring, studies to find the reason for the mass deaths and efforts to reduce the demand for the species as a food/traditional medicine.<ref name="CITESPeru2019" /><ref name="BolivianAmphibianInitiative" /><ref name="StiftungArtenschutz" /><ref name="Erbol2016">{{cite news|title=Titicaca: Equipo internacional rescata a la rana gigante | url=http://www.erbol.com.bo/video/titicaca_equipo_internacional_rescata_la_rana_gigante | publisher=Erbol Digital | date=2 March 2016 | archive-url=https://web.archive.org/web/20170916100433/http://www.erbol.com.bo/video/titicaca_equipo_internacional_rescata_la_rana_gigante | archive-date=16 September 2017 }}</ref> Education projects have resulted in some former frog poachers instead becoming part of a handicraft collective that provides a small alternative income.<ref name="Fobar2019" /> The possibility of offering ecotours where tourists can snorkel in a wetsuit and see the frogs is being considered at Isla de la Luna (where the species is still quite common), and a pilot project related to this was completed in 2017.<ref name="McKittrick2018" />
In 2020, scientists from Bolivia's Science Museum and Natural History Museum, Peru's Cayetano Heredia University, Pontifical Catholic University in Ecuador, Denver Zoo in the US and the NGO NaturalWay teamed up for further conservation efforts.<ref>{{Cite news|date=2020-07-27|title=Cross-border effort to save giant 'scrotum frog'|language=en-GB|work=BBC News|url=https://www.bbc.com/news/world-latin-america-53553636|access-date=2020-07-28}}</ref> ====Captive breeding==== [[File:Renacuajo de la Rana de Titicaca.jpg|thumb|Tadpole at the Parque de las leyendas (Huachipa Site) in 2025]] Following its rapid decline in the wild, it was decided in the early 2000s that a secure captive population should be established, which may form the basis for future reintroductions into places where it has disappeared.<ref name=BolivianAmphibianInitiative/><ref name=StiftungArtenschutz/><ref name=Erbol2016/> Early captive breeding attempts were unsuccessful;<ref name=amphibiaweb/> the only partial success was a few tadpoles hatched at the Bronx Zoo in the United States in the 1970s, but they did not metamorphose into frogs.<ref name=Nicholson2015>{{cite news | author=Nicholson, K. | date=25 November 2015 | title=Endangered Lake Titicaca frogs land at the Denver Zoo | url=https://www.denverpost.com/2015/11/25/endangered-lake-titicaca-frogs-land-at-the-denver-zoo/ | publisher=Denver Post | access-date=4 January 2020 }}</ref>
The first fully successful captive breeding was relatively recent: In 2010 it was first bred at Huachipa Zoo in Lima, Peru, and in 2012 it was first bred at Museo de Historia Natural Alcide d'Orbigny in Cochabamba, Bolivia.<ref name=LiveS2016/><ref>{{cite news|last1=Mendoza Miranda|first1=D.P. Clark|last2=Munoz|first2=A.|title=Ampliacíon del Programa de Cría en Cautiverio de género Telmatobius en Cochabama|url=http://bolivianamphibianinitiative.org/wp-content/uploads/2015/09/informe-cria-small.pdf|access-date=8 February 2017|publisher=Bolivian Amphibian Initiative}}</ref><ref name=AmphibiaWebCapt>{{cite web| title=The Titicaca Water Frog | url=https://amphibiaweb.org/amazing_amphibians/20131216_Telmatobius_culeus.html | publisher=AmphibiaWeb | access-date=4 January 2020 }}</ref> The breeding center in Bolivia is supported by Berlin Zoo, Germany,<ref name=BerlinZoo/> and also involves several other threatened Bolivian frogs.<ref name=Hess2019>{{cite web | author=Hess, E. | date=2 July 2019 | title=Romeo & Juliet: Summer Of Love! | url=https://www.globalwildlife.org/blog/romeo-juliet-summer-of-love/ | publisher=Global Wildlife Conservation | access-date=24 January 2020 }}</ref> As a result of disagreement between the museum that provided space for it and the local biologists running it, it was briefly put on pause in 2018,<ref name=McKittrick2018/> but has since been continued.<ref name=Hess2019/>
In 2015, the breeding project initiated in Peru was expanded when a group of Titicaca water frogs bred at Huachipa Zoo was sent to Denver Zoo, United States,<ref name=LiveS2016/><ref name=Nicholson2015/> which already supported the effort at Huachipa Zoo and was involved in the establishment of a laboratory and program working with the frogs at the Cayetano Heredia University in Lima, Peru.<ref name=AmphibiaWebCapt/> The first successful captive breeding outside its native South America happened at the Denver Zoo in 2017–2018 (first tadpoles in 2017, first metamorphosis into young frogs in 2018).<ref>{{cite web|title=Denver Zoo hatches first Lake Titicaca frog tadpoles in North American history |url=https://denverzoo.org/denver-zoo-hatches-first-lake-titicaca-frog-tadpoles-north-american-history |date=15 May 2017|publisher=Denver Zoo|access-date=6 January 2020 }}</ref><ref>{{cite web|title=Peru |url=https://www.denverzoo.org/peru/ |date=15 May 2017|publisher=Denver Zoo|access-date=6 January 2020 }}</ref> In 2019, some offspring from Denver were transferred to other US zoos and some to Chester Zoo in the United Kingdom, which redistributed them among several European zoos in an attempt of establishing another safe population. Among the European institutions, Diergaarde Blijdorp, Münster Zoo, Prague Zoo, Wrocław Zoo and WWT Slimbridge already managed to breed it in the first year.<ref>{{cite web|title=Titicaca water frog |url=https://www.zootierliste.de/en/?klasse=4&ordnung=403&familie=40311&art=55008111&haltungen=1 |publisher=Zootierliste|access-date=4 January 2020 }}</ref>
In early 2019 (prior to the breeding at several European institutions and not counting those at the breeding center in Bolivia), there were about 3,000 Titicaca water frogs at the breeding center in Peru, and 250 in zoos in North America and Europe.<ref>{{cite web | title=The frog as an aphrodisiac | url=http://www.zoo.wroclaw.pl/en/the-frog-as-an-aphrodisiac.htm | date=15 March 2019 | publisher=Zoo Wroclaw | access-date=4 January 2020 }}</ref> Captives have lived for up to 20 years.<ref name=LiveS2016/>
==References== {{Reflist}}
==External links== * [https://web.archive.org/web/20161117070307/http://www.arkive.org/titicaca-water-frog/telmatobius-culeus/ Titicaca Water Frog] on ARKive
{{Taxonbar|from=Q1628083}}
culeus Category:Amphibians of the Andes Category:Amphibians of Bolivia Category:Amphibians of Peru Category:Amphibians described in 1876 Category:Taxa named by Samuel Garman Category:Species that are or were threatened by use as food Category:Lake Titicaca