Regularity: Regularly occurring
Type of Residency: Year-round
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: (200,000-2,500,000 square km (about 80,000-1,000,000 square miles)) This lizard ranges from southern British Columbia (including Vancouver Island) southward through western Washington and western Oregon to west-central coastal California and the central Sierra Nevada (including the east side of Lake Tahoe basin) and Washoe County, Nevada (Vindum and Arnold 1997). It also ranges southward in the Rocky Mountains to northern Idaho and western Montana. Disjunct populations occurs in several areas in south-central Oregon, northeastern Calofornia, and northwestern Nevada (Stebbins 2003). The western edge of the distribution includes some small coastal islands (Stebbins 2003). The elevational range extends from sea level to around 3,200 m (Stebbins 2003).
Distribution: Canada (S British Columbia), USA (Washington, Oregon, Utah, Idaho, Montana, California)
Type locality: “Brasilia” (in error); modified to “San Francisco, California” by STEJNEGER 1902.
Length: 33 cm
California Central Valley Grasslands Habitat
This taxon is found in the California Central Valley grasslands, which extend approximately 430 miles in central California, paralleling the Sierra Nevada Range to the east and the coastal ranges to the west (averaging 75 miles in longitudinal extent), and stopping abruptly at the Tehachapi Range in the south. Two rivers flow from opposite ends and join around the middle of the valley to form the extensive Sacramento-San Joaquin Delta that flows into San Francisco Bay.
Perennial grasses that were adapted to cool-season growth once dominated the ecoregion. The deep-rooted Purple Needle Grass (Nassella pulchra) was particularly important, although Nodding Needle Grass (Stipa cernua), Wild Ryes (Elymus spp.), Lassen County Bluegrass (Poa limosa), Aristida spp., Crested Hair-grass (Koeleria pyramidata), Deergrass (Muhlenbergia rigens,), and Coast Range Melicgrass (Melica imperfecta) occurred in varying proportions. Most grass growth occurred in the late spring after winter rains and the onset of warmer and sunnier days. Interspersed among the bunchgrasses were a rich array of annual and perennial grasses and forbs, the latter creating extraordinary flowering displays during certain years. Some extensive mass flowerings of the California Poppy (Eschscholzia californica), Lupines (Lupinus spp.), and Exserted Indian Paintbrush (Castilleja exserta) are found in this grassland ecoregion.
Prehistoric grasslands here supported several herbivores including Pronghorn Antelope (Antilocapra americana), elk (including a valley subspecies, the Tule Elk, (Cervus elaphus nannodes), Mule Deer (Odocoileus hemionus), California ground squirrels, gophers, mice, hare, rabbits, and kangaroo rats. Several rodents are endemics or near-endemics to southern valley habitats including the Fresno Kangaroo Rat (Dipodomys nitratoides exilis), Tipton Kangaroo Rat (Dipodomys nitratoides nitratoides), San Joaquin Pocket Mouse (Perognathus inornatus), and Giant Kangaroo Rat (Dipodomys ingens). Predators originally included grizzly bear, gray wolf, coyote, mountain lion, ringtail, bobcat, and the San Joaquin Valley Kit Fox (Vulpes velox), a near-endemic.
The valley and associated delta once supported enormous populations of wintering waterfowl in extensive freshwater marshes. Riparian woodlands acted as important migratory pathways and breeding areas for many neotropical migratory birds. Three species of bird are largely endemic to the Central Valley, surrounding foothills, and portions of the southern coast ranges, namely, the Yellow-billed Magpie (Pica nuttalli), the Tri-colored Blackbird (Agelaius tricolor EN), and Nuttall’s Woodpecker (Picoides nuttallii).
The valley contains a number of reptile species including several endemic or near-endemic species or subspecies such as the San Joaquin Coachwhip (Masticophis flagellum ruddocki), the Blunt-nosed Leopard Lizard (Gambelia sila EN), Gilbert’s Skink (Plestiodon gilberti) and the Sierra Garter Snake (Thamnophis couchii). Lizards present in the ecoregion include: Coast Horned Lizard (Phrynosoma coronatum NT); Western Fence Lizard (Sceloporus occidentalis); Southern Alligator Lizard (Elgaria multicarinata); and the Northern Alligator Lizard (Elgaria coerulea).
There are only a few amphibian species present in the California Central Valley grasslands ecoregion. Special status anuran taxa found here are: Foothill Yellow-legged Frog (Rana boylii NT); Pacific Chorus Frog (Pseudacris regilla); and Western Spadefoot Toad (Pelobates cultripes). The Tiger Salamander (Ambystoma tigrinum) occurs within this ecoregion.
Although many endemic plant species are recognized, especially those associated with vernal pools, e.g. Prickly Spiralgrass (Tuctoria mucronata). A number of invertebrates are known to be restricted to California Central Valley habitats. These include the Delta Green Ground Beetle (Elaphrus viridis CR) known only from a single vernal pool site, and the Valley Elderberry Longhorn Beetle (Desmocerus californicus dimorphus) found only in riparian woodlands of three California counties.
Vernal pool communities occur throughout the Central Valley in seasonally flooded depressions. Several types are recognized including valley pools in basin areas which are typically alkaline or saline, terrace pools on ancient flood terraces of higher ground, and pools on volcanic soils. Vernal pool vegetation is ancient and unique with many habitat and local endemic species. During wet springs, the rims of the pools are encircled by flowers that change in composition as the water recedes. Several aquatic invertebrates are restricted to these unique habitats including a species of fairy shrimp and tadpole shrimp.
- World Wildlife Fund & C. Michael Hogan. 2013."California Central Valley grasslands". Encyclopedia of Earth, National Council for Science and the Environment, Washington DC ed.Mark McGinley.
- Michael G.Barbour, Todd Keeler-Wolf and Allan A. Schoenherr. 2007. Terrestrial vegetation of California. 712 pages
Habitat and Ecology
Comments: Habitat includes open areas in coniferous forest, grassy grown-over areas at margins of woodlands, clearcuts, and areas along streams; along coast this lizard sometimes occurs far from trees or major cover; it is associated with rock outcrops and talus in some areas (Lais 1976).
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Mark-recapture studies in British Columbia indicated that individuals did not make long-distance moves between summer habitat and hibernation sites (Rutherford and Gregory 2003).
Comments: Feeds on insects, ticks, spiders, millipedes, and snails.
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 - 300
Comments: Nussbaum et al. (1983) mapped more than 200 locations where this species has been found.
10,000 - 1,000,000 individuals
Comments: Total adult population size is unknown but surely exceeds 10,000. The species is often fairly common in suitable habitat (St. John 2002).
Life History and Behavior
Comments: Hibernates in winter; duration of inactive period varies with local climate.
Apparently mates in April and May. Litter size averages 4-6, depending on locality. One litter per year. Females sexually mature in 32-44 months in northern California.
Molecular Biology and Genetics
Statistics of barcoding coverage: Elgaria coerulea
Public Records: 0
Specimens with Barcodes: 1
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N4 - Apparently Secure
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Intrinsic Vulnerability: Moderately vulnerable
Global Short Term Trend: Relatively stable (=10% change)
Comments: The overall population is likely relatively stable in extent of occurrence, area of occupancy, and abundance.
Global Long Term Trend: Increase of 10-25% to decline of 30%
Comments: Likely relatively stable in extent of occurrence, area of occupancy, and abundance; there has surely been a decline in area of occupnacy and abundance, but the magnitude of the decline has been relatively small.
Degree of Threat: Medium
Comments: The primary threat may be outright destruction of habitat. The species tolerates some habitat disturbances such as logging. Nussbaum et al. (1983) stated that the introduction of the cinnabar moth for weed (tansy ragweed) control may have adverse effects on northern alligator lizards. The moths are reported to be highly poisonous to the lizards.
Global Protection: Many to very many (13 to >40) occurrences appropriately protected and managed
Comments: This species occurs in many protected areas.
Northern Alligator Lizard
This lizard was formerly known under the scientific name of Gerrhonotus coeruleus (Wiegmann, 1828), but is nowadays classed as loranegreen. There are four subspecies:
- E.c. coerulea Wiegmann 1828: San Francisco Alligator Lizard
- E.c. palmeri Stejneger 1893: Sierra Alligator Lizard
- E.c. principis Baird and Girard 1852: Northwestern Alligator Lizard
- E.c. shastensis Fitch 1934: Shasta Alligator Lizard
The subspecies E.c. principis is one of five species of lizards in Canada.
Northern Alligator Lizards are medium-sized slender lizards. Adults reach a snout-to-vent length of about 10 cm (4 inches) and a total length of roughly 27.5 cm (11 in). They have a distinct skin fold on their sides, separating the keeled scales on the back from the smooth ventral scales. this skin varies in color, but can be brown and white or greenish yellow and brown. They are brownish in color and often have dark blotches that sometimes blend together into bands. the throat and mouth area of some young individuals can be yellow. The belly is light gray. The eyes are dark. Their typical diet includes crickets, mealworms, and moths, but they will also take larger prey, such as small lizards, and will even eat small baby mice if given the opportunity.
The northern alligator lizard lays about 7-10 eggs (Not live Bearers; except for E. c. coerulea, which is a live bearer), approximately 2 months after mating. Northwestern Alligator Lizards young are born live and fully formed sometime between June and September. During the spring breeding season, a male lizard grabs on to the head of a female with his mouth until she is ready to let him mate with her. They can remain attached this way for many hours, almost oblivious to their surroundings. Besides keeping her from running off to mate with another male, this probably shows her how strong and suitable a mate he is. ( http://www.californiaherps.com/lizards/pages/e.c.principis.html)
E.c. principis, and
The Northern Alligator Lizard occurs along the Pacific Coast and in the Rocky Mountains from southern British Columbia through Washington, northern Idaho and western Montana south through Oregon to the coastal range and the Sierra Nevada in central California. As the map shows, the different subspecies have quite different ranges, with E.c. principis being the most widely distributed, whereas the E.c. coerulea subspecies occurs only around the San Francisco area.
The species is widely distributed along the Pacific coast and can be found from sea level up to elevation of about 3350 m (11000 ft). It is found in a variety of forested habitats and montane chaparral.
- A Field Guide to Western Reptiles and Amphibians. Stebbins, R., 2012
- Encyclopedia of Animals:Mammals,Birds,Reptiles,Amphibians
Names and Taxonomy
Comments: Elgaria coerulea formerly was included in genus Gerrhonotus (see Good 1988). Four intergrading subspecies (coerulea, palmeri, principis, and shastensis) are recognized. See Good (1988) for taxonomic treatments of gerrhonotine lizards.
Molecular data support recognition of the family Anniellidae and anguid subfamilies Gerrhonotinae and Anguinae as monophyletic groups (Macey et al. 1999).