The tail of an Ensatina is
constricted at the base
Some Ensatinas, like this one, are found without a tail. The tail is easily broken off, and sometimes it will be intentionally released by the salamander to distract a predator. The tail will grow back, but not always as long as it was before it broke.
A careful look underneath the fallen branches and bark of the dead tree shown above on a wet winter afternoon turned up 16 salamanders of 4 species - one Arboreal Salamander, two Coast Range Newts, one Yellow-eyed Ensatina, and 12 California Slender Salamanders, proving that wood debris on a forest floor is an important microhabitat for salamanders. Along with fallen debris, tree bark, tree cavities, root holes, and splits in trees are also useful habitat for many kinds of wildlife, including birds, mammals, amphibians and reptiles, but dead trees and their debris are often removed indiscriminately without consideration for wildlife.
Views of two Yellow-eyed Ensatina, the first from Contra Costa County, the second from the Santa Cruz Mountains.
An adult Ensatina measures from 1.5 - 3.2 inches long (3.8 - 8.1 cm) from snout to vent, and 3 - 6 inches (7.5 - 15.5 cm) in total length.
A medium-sized salamander.
The legs are long, and the body is relatively short, with 12 - 13 costal grooves.
Nasolabial grooves are present.
The tail is rounded and constricted at the base, which will differentiate this salamander from its neighbors.
Color and Pattern
A bright yellow patch on the eye gives this salamander its common name.
This subspecies is orange-brown to dark brown above, with orange coloring below, on the eyelids, and on the sides of the head, tail and body.
Yellow to orange coloring is present on the base of the limbs.
Young are dark above, with yellow or orange coloring on the base of the limbs.
Male / Female Differences
Males have longer, more slender tails than females, and a shorter snout with an enlarged upper lip, while the bodies of females are usually shorter and fatter than the bodies of males.
Life History and Behavior
A member of family Plethodontidae, the Plethodontid or Lungless Salamanders.
Plethodontid salamanders do not breathe through lungs. They conduct respiration through their skin and the tissues lining their mouth. This requires them to live in damp environments on land and to move about on the ground only during times of high humidity. (Plethodontid salamanders native to California do not inhabit streams or bodies of water but they are capable of surviving for a short time if they fall into water.)
Plethodontid salamanders are also distinguished by their naso-labial grooves, which are vertical slits between the nostrils and upper lip that are lined with glands associated with chemoreception.
All Plethodontid Salamanders native to California lay eggs in moist places on land.
The young develop in the egg and hatch directly into a tiny terrestrial salamander with the same body form as an adult.
(They do not hatch in the water and begin their lives as tiny swimming larvae breathing through gills like some other types of salamanders.)
Ensatina live in relatively cool moist places on land becoming most active on rainy or wet nights when temperatures are moderate. They stay underground during hot and dry periods where they are able to tolerate considerable dehydration.
They may also continue to feed underground during the summer months.
High-altitude populations are also inactive during severe winter cold.
Adults have been observed marking and defending territories outside of the breeding season.
Longevity has been estimated at up to 15 years.
When it feels severely threatened by a predator, an Ensatina may detach its tail from the body to distract the predator. The tail moves back and forth on the ground to attract the predator while the Ensatina slowly crawls away to safety. The tail can be re-grown.
The tail also contains a high density of poison glands. When disturbed, an Ensatina will stand tall in a stiff-legged defensive posture with its back swayed and the tail raised up while it secretes a milky white substance from the tail, swaying from side to side. This noxious substance repels predators, although some experienced predators learn to eat all but the tail. The poison is also exuded from glands on the head.
If a person gets the poison on their lips, they will experience some numbness for several hours. (Charles Brown - Ensatina.net)
Rarely, an Ensatina may make a hissing or squeaking sound when threatened, presumably to distract or frighten a predator.
Predators include Stellar's Jays, gartersnakes, and racoons.
(Kuchta and Parks, Lanoo ed. - Amphibian Declines... 2005)
Diet and Feeding
Ensatinas eat a wide variety of invertebrates, including worms, ants, beetles, spiders, scorpions, centipedes, millipedes, sow bugs, and snails.
They expell a relatively long sticky tongue from the mouth to capture the prey and pull it back into the mouth where it is crushed and killed, then swallowed.
Typically feeding is done using sit-and-wait ambush tactics, but sometimes Ensatinas will slowly stalk their prey.
"Rarely, it may produce a squeak or snakelike hiss, quite a feat for an animal without lungs!"
(Stebbins & McGinnis 2012)
This frightened Humboldt County Ensatina is raised up in defensive mode, excreting a milky white defensive liquid on its head and tail. It jerks its head several times, and each time it makes a very faint squeaking sound.
Reproduction is terrestrial.
Mating takes place in Fall and Spring, but may also occur throughout the winter.
Stebbins describes an elaborate Ensatina courtship involving the male rubbing his body and head against the female eventually dropping a sperm capsule onto the ground which the female picks up with her cloaca. A description and illustration of this courtship can be seen here. You can also watch an Ensatina courtship video on YouTube.
The female can store the sperm until she determines the time is right to fertilize her eggs.
At the end of the rainy season, typically April or May, females retreat to their aestivation site under bark, in rotting logs, or in underground animal burrows, and lay their eggs.
Females lay 3 - 25 eggs, with 9 - 16 being average.
Females remain with the eggs to guard them until they hatch. (You can see pictures of two Ensatinas with their eggs and hatchlings here.)
In labs, eggs have hatched in 113 - 177 days.
Young develop completely in the egg and probably leave the nesting site with the first saturating Fall rains, or, at higher elevations, after the snow melts.
Inhabits moist shaded evergreen and deciduous forests and oak woodlands, mixed grassland, and chaparral. Found under rocks, logs, other debris, especially bark that has peeled off and fallen beside logs and trees.
Most common where there is a lot of coarse woody debris on the forest foor. In dry or very cold weather, stays inside moist logs, animal burrows, under roots, woodrat nests, under rocks.
This subspecies, Ensatina eschscholtzii xanthoptica - Yellow-eyed Ensatina, is endemic to California, ranging from from near Healdsburg in Sonoma County, south along the east side of the San Francisco Bay to Santa Cruz County. (See comments under "Taxonomic Notes" below for the SF Peninsula Ensatina population.) A separate population occurs in the foothills of the central Sierra Nevada mountains. Yellow-eyed Ensatina were probably distributed from the Bay Area across the central valley when the climate there was cooler and moister, but as it became drier, two separate populations were formed.
Ensatina is the most widely-distributed plethodontid salamander in the West, ranging from an isolated location in the mountains of Baja California north along the extreme northwest coast of Baja California, through most of California excluding the deserts, the central valley, and high elevations in the mountains, continuing north into Oregon and Washington west of the Cascades Mountains, and farther north into Canada along the coast of southern British Columbia. Also found on Vancouver Island.
The range maps in Stebbins (2003 and 2012) show a very large range of intergradation between 4 subspecies in Northern California that at one time was considered part of the range E. e. oregonensis. I show this range on my maps as E. e. oregonensis partly because Stebbins & McGinnis, 2012, report that molecular studies have shown complexities that make the use of the term "intergrade" innacurate.
In his 2003 field guide, Stebbins shows the elevational range of Ensatina eschscholtzii as "Sea level to around 11,000 ft (3,350 m). That is for the species but not necessarily this subspecies.
Notes on Taxonomy
E. e. xanthoptica hybridizes with E. e. platensis in the Sierra Nevada foothills.
Ensatina taxonomy is controversial. The species Ensatina eschscholtzii traditionally consists of 7 subspecies:
Some researchers see Ensatina eschscholtzii as two or more species that make up a superspecies complex.
They recognize E. e. klauberi, found at the southern end of the ring, as a separate species - Ensatina klauberi.
Ensatina as a Ring Species
Ensatina eschscholtzii has been called a "ring" species, or "Rassenkreis" (race circle) "...a connected series of neighbouring populations, each of which can interbreed with closely sited related populations, but for which there exist at least two 'end' populations in the series, which are too distantly related to interbreed, though there is a potential gene flow between each 'linked' population. Such non-breeding, though genetically connected, 'end' populations may co-exist in the same region thus closing a 'ring'." (Wickipedia, 8/26/17) The "end" populations of Ensatina are the E. e. escholtzii and the E. e. klauberi subspecies, which hybridize in San Diego County.
Charles W. Brown explains the taxonomy of the Ensatina complex in detail, describing it as "a classical example of Darwinian evolution by gradualism; an accumulation of micro mutations that is now leading to the formation of a new species."
Illustration of the Ensatina ring:
Use: This file is licensed under the Creative Commons Attribution 2.0 Generic license.
Photo Credit: Thomas J. Devitt, Stuart J.E. Baird and Craig Moritz, 2011.
Source: (2011). "Asymmetric reproductive isolation between terminal forms of the salamander ring species Ensatina eschscholtzii revealed by fine-scale genetic analysis of a hybrid zone". BMC Evolutionary Biology 11 (1): 245. DOI:10.1186/1471-2148-11-245.
What Subspecies of Ensatina eschscholtzii Occurs in San Francisco?
Determining the taxonomy of Ensatina eschscholtzii in San Francisco County and the west side of the San Francisco Bay has been challenging:
The range maps in Stebbins, Robert C. Amphibians and Reptiles of Western North America. McGraw-Hill, 1954 and 1985 show them to be intergrades, but they do not indicate whether they itergrade with E. e. eschscholtzii or with E. e. oregonensis.
The large color range map in Thelander, Carl G., editor in chief. Life on the Edge - A Guide to California's Endangered Natural Resources - Wildlife. Berkeley: Bio Systems Books, 1994 that is based on two of Robert Stebbins' works appears to show them as intergrades with E. e. eschscholtzii, though that is not entirely clear.
The range map in Petranka, James W. Salamanders of the United States and Canada. Smithsonian Institution, 1998. shows them to be E. e. oregonensis.
The range maps in Stebbins, Robert C. A Field Guide to Western Amphibians and Reptiles Third Edition. Houghton Mifflin, 2003 and Fourth Edition 2018 are too small to show that part of the peninsula.
The range map in Joao Alexandrino, Stuart J. E. Baird, Lucinda Lawson, J. Robert Macey, Craig Moritz, and David B. Wake. Strong Selection Against Hybrids at a Hybrid Zone in the Ensatina Ring Species Complex and Its Evolutionary Implications. Evolution, 59(6), 2005, pp. 1334–1347 shows them to be E. e. oregonensis
David B. Wake. Problems with Species: Patterns and Processes of Species Formation in Salamanders. Annals of the Missouri Botanical Garden. 93: 8–23. Published on 31 May 2006 shows a range map (click here to see it) based on a preliminary analysis from a study in progress using mitochondrial DNA in which Ensatina on the SF peninsula are shown as E. e. xanthoptica but there are E. e. oregonensis clades shown on the coast south of there. (A color map in the same paper shows the entire area west of the S.F. Bay to beE. e. oregonensis.)
The map used by Devitt, et al, 2011, shown above in their illustration of the Ensatina ring, shows them to be E. e. oregonensis.
A range map in Shawn R. Kuchta, Duncan S. Parks, David B. Wake. Pronounced phylogeographic structure on a small spatial scale: Geomorphological evolution and lineage history in the salamander ring species Ensatina eschscholtzii in central coastal California. Molecular Phylogenetics and Evolution 50 (2009) 240–255 shows them to be E. e. xanthoptica (with E. e. oregonensis to the southwest.) (Click here to see the map.)
The range map in Stebbins, Robert C., and McGinnis, Samuel M. Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012 shows them to be E. e. xanthoptica.
There are certainly more studies with more maps which I have not seen, but since some recent research shows them as E. e. xanthoptica (and photos I've seen of Ensatina from San Francisco corroborate this) I will show them as such until further research shows otherwise.
Stebbins, Robert C., and McGinnis, Samuel M. Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012.
Stebbins, Robert C. California Amphibians and Reptiles. The University of California Press, 1972.
Flaxington, William C. Amphibians and Reptiles of California: Field Observations, Distribution, and Natural History. Fieldnotes Press, Anaheim, California, 2021.
Samuel M. McGinnis and Robert C. Stebbins. Peterson Field Guide to Western Reptiles & Amphibians. 4th Edition. Houghton Mifflin Harcourt Publishing Company, 2018.
Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.
Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.
Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998.
Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Amphibians of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009.
Bishop, Sherman C. Handbook of Salamanders. Cornell University Press, 1943.
Lannoo, Michael (Editor). Amphibian Declines: The Conservation Status of United States Species. University of California Press, June 2005.
Petranka, James W. Salamanders of the United States and Canada. Smithsonian Institution, 1998.
Joao Alexandrino, Stuart J. E. Baird, Lucinda Lawson, J. Robert Macey, Craig Moritz, and David B. Wake. Strong Selection Against Hybrids at a Hybrid Zone in the Ensatina Ring Species Complex and Its Evolutionary Implications. Evolution, 59(6), 2005, pp. 1334–1347.
Shawn R. Kuchta, Duncan S. Parks, David B. Wake. Pronounced phylogeographic structure on a small spatial scale: Geomorphological evolution and lineage history in the salamander ring species Ensatina eschscholtzii in central coastal California. Molecular Phylogenetics and Evolution 50 (2009) 240–255
The following conservation status listings for this animal are taken from the October 2021 California "Special Animals List" and the October 2021 "State and Federally Listed Endangered and Threatened Animals of California" list, both of which are produced by multiple agencies and available here: https://www.wildlife.ca.gov/Data/CNDDB/Plants-and-Animals. You can check the link to see if there are more recent lists.
If no status is listed here, the animal is not included on either list. This most likely indicates that there are no serious conservation concerns for the animal. To find out more about an animal's status you can go to the NatureServe and IUCN websites to check their rankings.
This salamander is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.