{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T21:13:37Z","timestamp":1792012417203,"version":"4.4.0"},"reference-count":30,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2013,7,31]],"date-time":"2013-07-31T00:00:00Z","timestamp":1375228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Anderson\u2019s crocodile newt (Echinotriton andersoni) is distributed in the Central Ryukyu Islands of southern Japan, but environmental degradation and illegal collection over the last several decades have devastated the local populations. It has therefore been listed as a class B1 endangered species in the IUCN Red List, indicating that it is at high risk of extinction in the wild. The species is also protected by law in both Okinawa and Kagoshima prefectures. An artificial insemination technique using hormonal injections could not be applied to the breeding of this species in the laboratory. In this study we naturally bred the species, and tested a laboratory farming technique using several male and female E. andersoni pairs collected from Okinawa, Amami, and Tokunoshima Islands and subsequently maintained in near-biotopic breeding cages. Among 378 eggs derived from 17 females, 319 (84.4%) became normal tailbud embryos, 274 (72.5%) hatched normally, 213 (56.3%) metamorphosed normally, and 141 (37.3%) became normal  two-month-old newts; in addition, 77 one- to three-year-old Tokunoshima newts and  32 Amami larvae are currently still growing normally. Over the last five breeding seasons, eggs were laid in-cage on slopes near the waterfront. Larvae were raised in nets maintained in a temperature-controlled water bath at 20 \u00b0C and fed live Tubifex. Metamorphosed newts were transferred to plastic containers containing wet sponges kept in a  temperature-controlled incubator at 22.5 \u00b0C and fed a cricket diet to promote healthy growth. This is the first published report of successfully propagating an endangered species by using breeding cages in a laboratory setting for captive breeding. Our findings on the natural breeding and raising of larvae and adults are useful in breeding this endangered species and can be applied to the preservation of other similarly wild and endangered species such as E. chinhaiensis.<\/jats:p>","DOI":"10.3390\/ani3030680","type":"journal-article","created":{"date-parts":[[2013,7,31]],"date-time":"2013-07-31T12:11:46Z","timestamp":1375272706000},"page":"680-692","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["An Attempt at Captive Breeding of the Endangered Newt Echinotriton andersoni, from the Central Ryukyus in Japan"],"prefix":"10.3390","volume":"3","author":[{"given":"Takeshi","family":"Igawa","sequence":"first","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirotaka","family":"Sugawara","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miyuki","family":"Tado","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takuma","family":"Nishitani","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atsushi","family":"Kurabayashi","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed","family":"Islam","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shohei","family":"Oumi","sequence":"additional","affiliation":[{"name":"Section of Agriculture and Forestry, Amami City Government, Amami, Kagoshima 894-0048, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seiki","family":"Katsuren","sequence":"additional","affiliation":[{"name":"Okinawa Prefectural Institute of Health and Environment, Okinawa 901-1202, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tamotsu","family":"Fujii","sequence":"additional","affiliation":[{"name":"Faculty of Human Culture & Science, Hiroshima Prefectural University, Hiroshima 734-8558, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masayuki","family":"Sumida","sequence":"additional","affiliation":[{"name":"Institute for Amphibian Biology, Graduate School of Science, Hiroshima University,  1-3-1 Kagamiyama, Higashihiroshima 739-8526, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2013,7,31]]},"reference":[{"key":"ref_1","first-page":"I","article-title":"Searching for a \u2018living fossil\u2019, Tylotriton andersoni","volume":"144","author":"Utsunomiya","year":"1973","journal-title":"Asahi-Larousse Weekly Animal Encyclopedia"},{"key":"ref_2","first-page":"1","article-title":"A note on the distribution of Tylotriton andersoni Boulenger in Okinawa Island","volume":"15","author":"Matayoshi","year":"1997","journal-title":"Biol. Mag. Okinawa"},{"key":"ref_3","unstructured":"Zhao, E-M., and Adler, K. (1993). Herpetology of China, Society for the Study of Amphibians and Reptiles."},{"key":"ref_4","unstructured":"Zhao, E. (1998). China Red Data Book of Endangered Animals: Amphibia and Reptilia, Science Press."},{"key":"ref_5","first-page":"234","article-title":"On Chinese herpetology","volume":"51","author":"Matsui","year":"1995","journal-title":"Herpetologica"},{"key":"ref_6","first-page":"117","article-title":"Negative impact of an invasive small Indian mongoose Herpestes javanicus on native wildlife species and evaluation of a control project in Amami-Ohshima and Okinawa Islands","volume":"8","author":"Yamada","year":"2004","journal-title":"Glob. Environ. Res. (Japan)"},{"key":"ref_7","unstructured":"IUCN Red List of Threatened Species. Available online:http:\/\/www.iucnredlist.org."},{"key":"ref_8","unstructured":"Uchiyama, R., Maeda, N., Numata, K., and Seki, S. (2005). Amphibians and Reptiles in Japan, Heibonsha. [4th ed.]. (in Japanese)."},{"key":"ref_9","first-page":"11","article-title":"A note on the spawning of Tylotriton andersoni Boulenger in Okinawa Island","volume":"16","author":"Matayoshi","year":"1978","journal-title":"Biol. Mag. Okinawa"},{"key":"ref_10","first-page":"13","article-title":"Preliminary observations on ecology of the subtropical newts Tylotriton (Echinotriton) andersoni Tylotriton and Cynopus ensicauda in Sesokojima Island, the Ryukyu Islands","volume":"26","author":"Tanaka","year":"1994","journal-title":"J. Biol. Educ."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"67","DOI":"10.5358\/hsj.21.67","article-title":"Male courtship behavior of Tylotriton (Echinotriton) andersoni Boulenger under laboratory condition","volume":"21","author":"Utsunomiya","year":"2002","journal-title":"Current Herpetol."},{"key":"ref_12","first-page":"115","article-title":"Record of the egg-laying behavior of Anderson\u2019s crocodile newt (Echinotriton andersoni) from Tokunoshima (in Japanese)","volume":"2011","author":"Sugawara","year":"2011","journal-title":"Bull. Herpetol. Soc. Japan"},{"key":"ref_13","first-page":"4","article-title":"Bemerkungen zu Echinotriton andersoni von den Japanischen Inseln Tokunoshima und Okinawa sowie zur Nachzucht von Tieren der Tokunoshima-Form","volume":"5","author":"Fleck","year":"2006","journal-title":"Amphibia"},{"key":"ref_14","first-page":"2","article-title":"Amphibian Conservation at the Detroit Zoological Institute","volume":"40","author":"Snider","year":"2000","journal-title":"Froglog"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"25","DOI":"10.11646\/zootaxa.2767.1.3","article-title":"Inter- and intra-island divergence in Odorrana ishikawae (Anura, Ranidae) of the Ryukyu Archipelago of Japan, with description of a new species","volume":"2767","author":"Kuramoto","year":"2011","journal-title":"Zootaxa"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"111","DOI":"10.5358\/hsj.30.111","article-title":"On the brown frogs from the Ryukyu Archipelago, Japan, with descriptions of two new species (Amphibia, Anura)","volume":"30","author":"Matsui","year":"2012","journal-title":"Current Herpetol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1038\/hdy.2012.59","article-title":"Population structure and landscape genetics of two endangered frog species of genus Odorrana: Different scenarios on two islands","volume":"110","author":"Igawa","year":"2013","journal-title":"Heredity"},{"key":"ref_18","first-page":"178","article-title":"Allozyme variation in the newt Tylototriton andersoni from three islands of the Ryukyu Archipelago","volume":"48","author":"Hayashi","year":"1992","journal-title":"Herpetologica"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1266\/ggs.87.39","article-title":"Mitochondrial genomes and divergence times of crocodile newts: Inter-islands distribution of Echinotriton andersoni and the origin of a unique repetitive sequence found in Tylototriton mt genomes","volume":"87","author":"Kurabayashi","year":"2012","journal-title":"Genes Genet. Syst."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1016\/j.ympev.2012.07.019","article-title":"Phylogeny and biogeography of the Anderson\u2019s crocodile newt, Echinotriton andersoni (Amphibia: Caudata), as revealed by mitochondrial DNA sequences","volume":"65","author":"Honda","year":"2012","journal-title":"Mol. Phylogenet. Evol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"595","DOI":"10.1007\/s12686-012-9600-2","article-title":"Isolation and characterization of ten microsatellite loci of endangered Anderson\u2019s crocodile newt. Echinotriton andersoni","volume":"4","author":"Sugawara","year":"2012","journal-title":"Conserv. Genet. Resour."},{"key":"ref_22","unstructured":"Igawa, T., Sugawara, H., Honda, M., Tominaga, A., Oumi, S., Katsuren, S., Ota, H., Matsui, M., and Sumida, M. (2013). Fine scale population structure and genetic divergence of Anderson\u2019s crocodile newt, Echinotriton andersoni. in preparation."},{"key":"ref_23","first-page":"65","article-title":"On the development of Tylototriton andersoni","volume":"16","author":"Utsunomiya","year":"1997","journal-title":"J. Fac. Fish. Anim. Husb."},{"key":"ref_24","first-page":"75","article-title":"Amphibians","volume":"Volume 1","author":"Egami","year":"1982","journal-title":"Lecture for Experimental Biology. Method for Preparing Experimental Materials"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"834","DOI":"10.2108\/zsj.28.834","article-title":"Artificial production and natural breeding of the endangered frog species Odorrana ishikawae, with special reference to fauna conservation in the laboratory","volume":"28","author":"Sumida","year":"2011","journal-title":"Zool. Sci."},{"key":"ref_26","unstructured":"Utsunomiya, T. (1998). Data Book on Rare Wild Aquatic Organism in Japan, Japan Fisheries Resource Conservation Association. (in Japanese)."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1007\/s10646-011-0658-5","article-title":"Agricultural intensity in ovo affects growth, metamorphic development and sexual differentiation in the common toad (Bufo bufo)","volume":"20","author":"Orton","year":"2011","journal-title":"Ecotoxicology"},{"key":"ref_28","unstructured":"Maeda, N., and Matsui, M. (1999). Frogs and Toads of Japan, Bunichi-Sogo Shuppan."},{"key":"ref_29","unstructured":"Ota, H. (2003). Endangered Wild Animals and Plants in Kagoshima Prefecture, Kagoshima Environmental Research and Service. (in Japanese)."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"733","DOI":"10.1016\/j.ympev.2005.04.030","article-title":"Multiple invasions of the Ryukyu archipelago by Oriental frogs of the subgenus Odorrana with phylogenetic reassessment of the related subgenera of the genus Rana","volume":"37","author":"Matsui","year":"2005","journal-title":"Mol. Phylogenet. Evol."}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/3\/3\/680\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:48:20Z","timestamp":1760219300000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/3\/3\/680"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,7,31]]},"references-count":30,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2013,9]]}},"alternative-id":["ani3030680"],"URL":"https:\/\/doi.org\/10.3390\/ani3030680","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2013,7,31]]}}}