California Newt

A large-bodied salamander. Terrestrial adults have a light brown to dark brown dorsum with a yellowish to orange belly. The skin is dry with small bumps or warts and costal grooves are not visible. The eyes are large and the lower eyelids are yellow. Adult males in the breeding season develop smooth or slimy skin, a lighter body color, enlarged tail fins, and swollen cloacal glands (Storer, 1925; Stebbins, 1985). Adults are 6.9 - 8.7 cm snout to vent lenght (12.5 - 20 cm total length) (Stebbins 1985; Petranka 1998). Two allopatric subspecies are currently recognized based on geographic distribution (see below) and coloration. Taricha t. sierrae, the Sierra newt, is reddish to chocolate brown dorsally and burnt orange to yellow below. The eyelids and snout have conspicuous light coloring. Taricha t. torosa, the Coast Range newt, is yellowish to dark brown dorsally and pale yellow to orange ventrally. The eyelids and snout are not as conspicuously colored as in T. t. sierrae. (Riemer 1958; Stebbins 1985; Petranka 1998). Hatchlings are 10-14 mm total length. The larvae are pond type with bushy gills, balancer organs and a well-developed dorsal tail fin which extends forward to the shoulder region (Stebbins 1985; Petranka 1998). The dorsum of larvae is light yellow with two dark, narrow bands (Riemer 1958; Stebbins 1985). Taricha torosa may be distinguished from close relatives (T. granulosa and T. rivularis) by the Y-shaped pattern of the vomerine teeth, the light-colored lower eyelids, relatively large eyes, and lack of a tomato red belly. The defensive posture differs between T. torosa and T. granulosa (see below) (Petranka 1998).Extremely warty newts found in many localities in San Diego County have been described as a separate subspecies, T. t. klauberi (Riemer 1958). This subspecies is not currently recognized because the presence of warts is thought to be caused by a pathogenic agent (Stebbins 1951; 1985). This species was formerly a subspecies, Taricha torosa torosa, and now both T. t. torosa and T. t. sierrae are recognized as a full species respectively(Kuchta 2007).UC Berkeley's Botanical Garden Director explains Newts mating onsite:Deep Look into NewtsThis species was featured as News of the Week on March 23, 2020:Climate change is a growing threat to amphibians, in large part because of more frequent extreme heat and drought events. Using 10 years of survey and mark-recapture data, Bucciarelli et al. (2020) recently showed that populations of California newts (Taricha torosa) – a widespread species across California – have been impacted by extreme climate events in recent years, particularly in southern California where climate change is already more pronounced. Specifically, from 2008 to 2016, California newt body condition (body mass relative to newt length) decreased by 20% in response to extreme heat and drought. Newt survival also decreased over time in response to climate change. These effects were not seen in the northern part of the California newt’s range where climate change has been less pronounced. Even so, modeling suggests that climate change in northern California will be as severe or worse for newt populations. This work highlights the critical impact climate change will have on amphibian population declines and extinctions in the coming years, both on its own and also by exacerbating other serious threats like habitat loss and disease (Written by Max Lambert). See other species accounts at www.californiaherps.com.

The Coast Range newt, T. t. torosa, ranges from Mendocino Co. south through the Coast Range to the western slope of the Peninsular ranges in San Diego Co. The southern-most locality (San Diego Co.) is isolated geographically from the remaining coastal populations. A gap in the distribution also exists in Santa Barbara Co. (Jennings and Hayes 1994; Stebbins 1985). The Sierra newt, T. t. sierrae, has a disjunct population in Shasta Co. and ranges along the western slopes of the Sierra Nevada south to Kern Co. (Stebbins 1985). Terrestrial adults are found in mesic forests in relatively mountainous areas of northern California. Further south, they can be found in drier habitats such as oak woodlands or hilly grasslands. Sierran populations are found in habitats dominated by conifers (digger pines-blue oak and ponderosa pine communities) (Petranka 1998). Breeding sites include ponds, reservoirs, and slow moving streams. Sierran populations breed in faster moving streams than coastal populations (Stebbins 1985; Petranka 1998).

The breeding season ranges from late December and early May, depending on location, and lasts 6-12 weeks. Breeding aggregations form primarily in ponds and lakes. Stream-breeding is more common in sierran populations and tends to occur late in the season for coastal populations. Courtship involves amplexus of the female by the male who then rubs his head on hers. Eventually the male deposits a spermatophore on the substrate which the female picks up in her cloaca. Shortly after mating, the female lays her eggs in small clusters containing 7-30 eggs. Time to hatching ranges from 2 weeks to 2 1/2 months, depending on water temperature. Diet items include earthworms, snails, slugs, insects, and conspecific eggs and larvae. See Petranka (1998) for references. All species of Taricha possess the potent neurotoxin tetrodotoxin, that is used as an antipredator defense (Brodie et al. 1974). Tetrodotoxin is also harmful to humans (e.g. Petranka 1998). When harassed, Taricha assume the “unken reflex” where the head is raised, the tail is turned up and held straight over the body, the limbs are extended, and the eyes are closed (Riemer 1958; Brodie 1977). This action exposes the bright aposomatic coloration found on the newt's belly. The exact pattern of this reflex is a species-specific character, distinguishable from sympatric T. granulosa, which curls the tip of the tail (Stebbins 1985; Petranka 1998).

Loss and degradation of stream habitats, and predation on eggs and larvae by introduced predators such as crayfish and mosquitofish, are a serious concern for populations of T. t. torosa in southern California (Jennings and Hayes 1994; Gamradt and Kats 1996). Road-kill is also a large source of adult mortality. Furthermore, UV-B radiation has been shown to cause reduced hatching success (Anzalone et al. 1998; Blaustein et al. 1998).

No known relation.