red-bellied newt
{{Short description|Species of amphibian}}
{{Speciesbox
| image = Red Bellied Newt (Taricha rivularis).jpg
| status = VU
| status_system = IUCN3.1
| genus = Taricha
| species = rivularis
| authority = (Twitty, 1935)
| range_map = Taricha rivularis distribution.png
| range_map_caption = Red-bellied newt distribution
}}
The red-bellied newt (Taricha rivularis) is a newt that is native to coastal woodlands in northern California and is terrestrial for most of its life.
Description
When full grown, the red-bellied newt measures between {{convert|2.75|to|3.5|in|abbr=on}} from its nose to its vent, and between {{convert|5.5|and|7.5|in|abbr=on}} from its nose to its tail. It has grainy skin, and is brownish-black on top with a tomato-red underbelly.Californiaherps.com [http://www.californiaherps.com/salamanders/pages/t.rivularis.html Taricha rivularis – Red-bellied Newt]. californiaherps.com The male red-bellied newt often has a dark, broad coloring across the vent, while females do not.{{Cite web|title=Red-bellied Newt - Taricha rivularis|url=http://www.californiaherps.com/salamanders/pages/t.rivularis.html|access-date=2020-11-11|website=www.californiaherps.com}} Breeding males develop smooth skin and a flattened tail. The red-bellied newt can be distinguished from other coastal newts by its red belly and a lack of yellow in its eyes.
Distribution and habitat
The red-bellied newt is found in California along the coast from Bodega in Sonoma County, inland to Lower Lake, and north to Honeydew, Humboldt County.Stebbins, Robert C.; Amphibians and Reptiles of California; University of California Press, Berkeley, 1972 p. 52 It lives in coastal woodlands, especially in redwood forests. There is a disjunct population {{convert|130|km|mi}} south of Sonoma County in the upper watershed of Stevens Creek in the Santa Cruz Mountains that is genetically identical to the Sonoma County population.{{cite journal |title=Discovery of a New, Disjunct Population of a Narrowly Distributed Salamander (Taricha rivularis) in California Presents Conservation Challenges |author1=Sean B. Reilly |author2=Daniel M. Portik |author3=Michelle S. Koo |author4=David B. Wake |journal=Journal of Herpetology |year=2014 |volume=48 |number=3 |pages=371–379 |doi=10.1670/13-066 |s2cid=3957581 |url=https://bioone.org/journals/journal-of-herpetology/volume-48/issue-3/13-066/Discovery-of-a-New-Disjunct-Population-of-a-Narrowly-Distributed/10.1670/13-066.short |accessdate=January 31, 2021}}{{cite news |title=The Mysterious Red Belly. A visit with Stevens Creek's resident enigmas |author=Tony Iwane |magazine=Bay Nature |date=January 3, 2021 |url=https://baynature.org/article/the-mysterious-red-belly/?mc_cid=0534fafa59&mc_eid=fbd4e05426 |accessdate=January 31, 2021}}
Reproduction and ecology
Newts begin their lives as aquatic larvae similar to tadpoles, though elongated and with external gills. Once newt larvae mature into their adult form, which takes about four to six months, they will leave the water and live underground{{Cite web|title=AmphibiaWeb - Taricha rivularis|url=https://amphibiaweb.org/species/4289|access-date=2020-11-11|website=amphibiaweb.org}} until they are ready to breed, which is typically in four to six years.{{Cite web|title=Red-bellied Newt - Taricha rivularis|url=http://www.californiaherps.com/salamanders/pages/t.rivularis.html|access-date=2020-11-11|website=www.californiaherps.com}} Red-bellied newts can live for 20-30 years.{{Cite web|title=AmphibiaWeb - Taricha rivularis|url=https://amphibiaweb.org/species/4289|access-date=2020-11-11|website=amphibiaweb.org}}
After reaching reproductive maturity, male red-bellied newts start congregating at stream banks as early as January or February. One to three weeks later, the females join them and the newts mate. Red-bellied newts lay their eggs in fast-flowing streams or rocky rivers. The females lay their eggs in about 12 streamlined clusters with six to 16 eggs each,[http://www.enature.com/fieldguides/detail.asp?recnum=AR0049 Red-bellied Newt (Taricha rivularis)]. enature.com and the eggs are typically attached to the bottoms of rocks, or on branches and roots leaning into the stream.Stebbins, Robert C.; Amphibians and Reptiles of California; University of California Press, Berkeley, 1972 p. 52 When the adults leave the stream, instead of moving directly uphill, they move at an angle that leads them somewhat upstream.{{cite journal|author=Twitty, V.|author2=Grant, D.|author3=Anderson, O.|name-list-style=amp |pmid=17792064|year=1967|title=Amphibian orientation: An unexpected observation|volume=155|issue=3760|pages=352–3|doi=10.1126/science.155.3760.352|journal=Science|bibcode=1967Sci...155..352T|s2cid=41486745}} The females, unlike the males, do not breed every year.[https://web.archive.org/web/20070307092149/http://www.livingunderworld.org/caudata/database/salamandridae/taricha/ Taricha (Gray, 1850) Western Newts, Pacific Newts]. livingunderworld.com
Homing
Red-bellied newts have a remarkable homing ability. They make great efforts to always go back to the same spot on the stream. They find their way over several miles of rugged terrain to get back to the spot.{{cite journal|author=Twitty, V.|author2=Grand, D.|author3=Anderson, O.|name-list-style=amp |year=1964|pmc=300603|pmid=16591135|title=Long distance homing in the newt Taricha rivularis|volume=51|issue=1|pages=51–8|journal=Proceedings of the National Academy of Sciences of the United States of America|doi=10.1073/pnas.51.1.51|bibcode=1964PNAS...51...51T|doi-access=free}} Likely, smell is responsible for the homing ability.{{cite journal|author=Grant, D.|author2=Anderson, O.|author3=Twitty, V.|name-list-style=amp |year=1968|title=Homing Orientation by Olfaction in Newts (Taricha rivularis)|pmid=5651897|volume=160|issue=3834|pages=1354–6|journal=Science|doi=10.1126/science.160.3834.1354|bibcode=1968Sci...160.1354G|s2cid=34974609}}
Defense
Red-bellied newts have a brownish-black topside to avoid being noticed. When that fails, and they are seen and disturbed, they pull their heads and tails back to reveal their bright-red undersides. This serves as a warning to potential predators, as red-bellied newts have enough of a neurotoxin, tetrodotoxin, in their skin, eggs, and embryos to potentially kill an adult human,[https://web.archive.org/web/20070307092149/http://www.livingunderworld.org/caudata/database/salamandridae/taricha/ Taricha (Gray, 1850) Western Newts, Pacific Newts]. livingunderworld.com or 1,200 to 2,500 mice.{{Cite web|title=AmphibiaWeb - Taricha rivularis|url=https://amphibiaweb.org/species/4289|access-date=2020-11-11|website=amphibiaweb.org}} Because red-bellied newts are so poisonous, they are nearly inedible and have no reported predators other than a few species of snake which are resistant to the toxin.{{Cite web|title=Red-bellied Newt - Taricha rivularis|url=http://www.californiaherps.com/salamanders/pages/t.rivularis.html|access-date=2020-11-11|website=www.californiaherps.com}} Like other newts, red-bellied newts have the ability to regenerate several body parts, including their limbs, eyes, hearts, intestines, upper and lower jaws, and damaged spinal cords.Shannon Odelberg. [https://web.archive.org/web/20090115062737/http://www.bioscience.utah.edu/mb/mbFaculty/odelberg/odelberg.html Research]. bioscience.utah.edu
References
{{Reflist}}
External links
- http://www.californiaherps.com/salamanders/pages/t.rivularis.html
- [http://depts.washington.edu/natmap/maps/CA_maphtml/a008.html Range map]
- [http://www.pwrc.usgs.gov/armiatlas/species.cfm?recordID=173621 Range map]
- [http://www.livingunderworld.org/caudata/database/salamandridae/taricha/]
{{Taxonbar|from=Q2275994}}
Category:Amphibians of the United States
Category:Endangered fauna of California