INTRODUCTION: During the wet winter season in Shelter Cove, and especially in springtime, several different kinds of amphibians can be found. Even in drier times of year, it is not uncommon to lift up a log or rock and find an amphibian keeping itself underneath in a moist microenvironment. Amphibians include salamanders and newts as well as frogs and toads, and they depend upon moist environments for survival. Adult amphibians may have lungs for air-breathing, but they also obtain oxygen across their thin skins, which need to be moist for this to be effective. Most amphibians also require standing water in order to lay eggs to bring the next generation of their species. A particularly interesting aspect of amphibians is that their younger larvae have gills and swimming fins for life in water (the larvae are commonly called tadpoles), but then will later undergo significant development into air-breathing (with lungs) adults with four legs for moving around on land. This dramatic developmental process from a "fish-like" juvenile into an adult with lungs and legs is called metamorphosis. There are also some interesting variations on how metamorphosis proceeds depending upon the species -the words "neoteny" and "paedomorphosis" are used to describe such variations which, for example, explains why some species may retain fish-like bodies but become reproductive adults. In the Descriptions provided below, these and other aspects of their biology are described further, and there are also links to additional information.
Finding and identifying amphibians requires that one knows a few things about their biology. First and foremost, keep in mind that they will be most active and easy to find in the winter and especially in spring; in the summer and fall, however, they will likely to be underground or under objects like logs and rocks, in order to avoid drying which can kill them. As you look for amphibians, know what their habitat needs are, for example if they are likely to be in water or on land, and know what they eat and how they reproduce. The Descriptions and Pictures below start you out with some useful information for selected amphibians likely to be found in and around Shelter Cove. The short Descriptions will help you to know a few facts that can help you find and identify different amphibian species - they also include some interesting additional facts and provide links to the photo and other sites that provide more information.
When you go out to find amphibians, make sure you have the following:
1. What will the amphibian be doing this time (season) of year? (find out below!)
2. In what type of habitat will the amphibian most likely be found? (find out below!)
3. Are you looking for a tadpole in spring, or an adult on land, or a neotenic body form in water? (find out below!)
4. Do you know the coloration patterns of males and females? (find out below!)
5. Bring your camera!
Quick-Links for each amphibian species listed in the Shelter Cove Wild Animals Guide given here:
Northwestern Salamander (Ambystoma gracile): found along the Mendocino and Humboldt County coasts, and coast range forests, north into British Columbia; 3-5 inches (7-13 cm) in length with a stout body, rounded head and blunt snout; dark brown, gray or black in color; aquatic larvae (‘tadpoles’) have gills and large tailfin for swimming, and then later undergo metamorphosis into adult form with four legs and lungs for air-breathing in terrestrial environments; notably, some adults may remain in aquatic environments and will develop legs but keep their gills and finned tails –this partial metamorphosis to keep some juvenile features in an adult is called ‘neoteny’ or ‘pedomorphosis’; terrestrial adults are typically found in underground burrows or under surface objects, or at water's surface during rain; they eat small invertebrates (insects, crustaceans) and even tadpoles; they make a ticking sound when engaging in aggressive or defensive behavior, and when threatened, will elevate tail while secreting a sticky white poison that can sicken or kill small animals.
Coastal Giant Salamander (Dicamptodon tenebrosus): found along Mendocino and Humboldt County coastal and coast range areas north to Washington State, favoring wet forests with clear cold streams, rivers, lakes and ponds; typically shelters under rocks, logs, or leaf litter, or in root channels during the day, and is typically more active nocturnally; largest terrestrial salamander in North America, with adults up to 13 inches (34 cm) long with stout head and limbs and flattened tail for moving in water; dark brown to near-black color with light brown spotting or marbling; a similar species, the California Giant Salamander (Dicamptodon ensatus), is difficult to distinguish from the Coastal Giant Salamander except for the presence of marbling patterns on the chin and throat of D. ensatus; aquatic larvae (‘tadpoles’) have gills and large tailfin for swimming, and then later undergo metamorphosis into adult form with four legs and lungs for air-breathing in terrestrial environments; notably, some adults may remain in aquatic environments and will develop legs but keep their gills and finned tails –this partial metamorphosis to keep some juvenile features in an adult is called ‘neoteny’ or ‘pedomorphosis’; large adults can defend themselves by delivering a painful bite, and their skin produces noxious secretions to discourage predators; they will eat almost anything they can fit into their mouth, including a variety of invertebrates as well as small vertebrates.
Speckled Black Salamander (Aneides flavipunctatus): found along the coast and coast ranges from Sonoma County north through Humboldt County and into far-SW Oregon; adults are up to 5 inches (13 cm) long; color varies according to location—in Humboldt County they may appear green, grey or dark black with lighter speckled patterns (some individuals may be black without patterns); toes have rounded tips; the family that includes this species (Family Plethodontidae) do not breath using lungs, and instead all respiration occurs across the skin and mouth linings—this requires them to live in damp locations and to move around only during times of high humidity like rainstorms; they do not live in water, but rather on the humid floor of damp forests, often under objects during day; they mostly eat small invertebrates; they typically flee from predators into leaf litter, but they may also bite and/or release noxious skin secretions.
BACK... to Shelter Cove AMPHIBIANS QUICK-LINKS
Arboreal Salamander (Aneides lugubris): found along the California coast and coast range from San Diego north to Humboldt County; adults range up to 7 inches (18 cm) in length, and are found in moist places on land, often in coastal oak woodlands; most active at night or with rainfall; light-to-dark brown skin often with yellow speckles or spots, but they can change their pigmentation in response to temperature and other cues; toes have expanded tips that help in climbing cliffs and tree trunks; tail is prehensile and often coiled; sharp teeth are used in conflicts or as defense (and can draw blood from human fingers!); they will also produce a squeak sound when disturbed, and will flee rapidly and can jump; the family that includes this species (Family Plethodontidae) do not breath using lungs, and instead all respiration occurs across the skin and mouth linings—this requires them to live in damp environments; they are ‘sit-and-wait’ predators that feed on a variety of small invertebrates using tongue capture and crushing using strong jaws.
Wandering Salamander (Aneides vagrans): found in north coast and coast range forests between Sonoma County north to Del Norte County; adults are 3-5 inches (7-13 cm) in length, slim and long-legged with expanded toe tips and a rounded prehensile tail; avid climbers and can be found in trees up to 300 feet (90 m) above ground (e.g., in Redwood or Douglas Fir trees), as well as in or under fallen logs and moist forest floor; dark brown in color with lighter-colored or golden blotch patterns across back and head; the family that includes this species (Family Plethodontidae) do not breath using lungs, and instead all respiration occurs across the skin and mouth linings—this requires them to live in damp environments; active on wet nights, ‘sit-and-wait’ predators of small invertebrates that come by; they are not as aggressive as other Plethodontids, and typically flee or remain motionless as a defense
California Slender Salamander (Batrachoseps attenuatus): very common, found in coastal and coast range environments from Monterey County north to Del Norte County; adults are 3-5 inches (7-14 cm), with a long slender body and narrow head, with very short limbs with 4 (not 5 like most other salamanders) toes on the hind feet; vary in coloration according to location –in Humboldt County they typically have dark bodies with dorsal reddish gold and brown spotting; the family that includes this species (Family Plethodontidae) do not breath using lungs, and instead all respiration occurs across the skin and mouth linings—this requires them to live in damp environments; most active on wet nights or in moist forest floor; they do not travel beyond 6-7 feet (2 m) during their entire life and they are thought to live for up to 10 years; ‘sit-and-wait’ predator that uses its projectile tongue to catch small invertebrates; they have several defense tactics, including coiling up, remaining still relying on their cryptic coloration, fleeing, and wiggling their tail for a predator to eat –after which a new tail will slowly grow back.
PCEC Video of Batrachoseps attenuatus in coastal Humboldt County, California USA
Oregon Ensatina (Ensatina eschscholtzii oregonensis): found in cool and moist coastal to coast range forests from Marin County north to British Columbia; adults are 3-6 inches (7-15 cm) in length with large protruding dark eyes and a characteristic constriction (smaller diameter) in the base of the tail; in Humboldt County, they have a reddish-to-dark-brown back coloration, sometimes with small yellow flecking, and yellow/orange sides; the family that includes this species (Family Plethodontidae) do not breath using lungs, and instead all respiration occurs across the skin and mouth linings—this requires them to live in damp environments; most active on wet nights, will stay underground during dry periods; ‘sit-and-wait’ predators, but may also stalk their prey, using a long sticky tongue to capture a wide variety of invertebrates; when threatened, they may produce a hissing sound (similar to a snake) but their principal defense is to detach their tail at its constriction, leaving a wiggling tail to distract the predator while it slowly crawls to safety.
Southern Torrent Salamander (Rhyacotriton variegatus): found in coastal forests from Mendocino County north to central coast of Oregon; adults are 2-3 inches (6-9 cm) in length with slim bodies, short tail, and a small head with large protruding dark eyes; large dark eyes have gold reflective speckling in iris; body coloring is brown dorsally with orange/yellow speckling, while sides and ventral surfaces are yellowish with speckled patterning; small lungs mean that the skin serves as a critical respiratory organ that must remain moist; the species is primarily aquatic, but capable of terrestrial activity in moist environments; in flowing streams, they may be found burrowed into stream bed substrates; diet includes aquatic invertebrates.
Rough-skinned newt (Taricha granulosa): found along the Pacific Coast from the Bay Area to southern Alaska; adults are 3-8 inches (9-20 cm) in length, with dry darkly-colored granular skin on back, and bright orange/yellow undersides; eyes have dark lower lids and reflective yellow irises; uses lungs as primary respiration in a mostly terrestrial life; often seen crawling overland during daytimes, but will take on aquatic form for breeding season including flattened tails to assist in swimming and specialized toe pads to hold onto mates; live up to 12 years old, with a strong defense against predators consisting of the potent neurotoxin, tetrodotoxin, produced in its skin and muscles—to warn predators, it turns its tail up over its head which displays a bright yellow/orange coloration; eating newts could kill a human, but garter snakes (Thamnophis sirtalis) eat them and store the poison for their own defense purposes!; diet consists of a broad range of invertebrates but also vertebrates like small fish or amphibian eggs and larvae.
Red-bellied newt (Taricha rivularis): found in southern Humboldt County south into Sonoma County; adults are 5-7 inches (14-20 cm) in length, with dark brown back and tail and bright tomato-red undersides (except limbs that have dark undersides); unlike other Taricha species, they have dark eyes without yellow irises; uses lungs as primary respiration in a mostly terrestrial life; often seen crawling overland during daytimes, but will take on aquatic form for breeding season including flattened tails to assist in swimming and specialized toe pads to hold onto mates; most active at night and late afternoon, during rain, or in streams (not in still waters like ponds where T. granulosa may reside)—in summer, they burrow in moist habitats; believed to live as long as 20-30 years, with a strong defense against predators consisting of the potent neurotoxin, tetrodotoxin, produced in its skin and muscles—to warn predators, it turns its tail up over its head which exposes their bright red coloration; eating newts could kill a human, but garter snakes (Thamnophis sirtalis) can eat them and store the poison for their own defense purposes!; diet consists of a broad range of invertebrates.
Boreal Toad (Anaxyrus boreas boreas): found in western North America from Northern California and Nevada to western Canada and Alaska; prefers edge of water bodies from marshes to creeks; adults are 2-5 inches (5-13 cm) from snout to vent, greenish/reddish-colored, dry and warty skin, with a more pale throat coloration; large forward-looking eyes with horizontal pupils; active nocturnally in summer, diurnally in wet wintertime, and crawl slowly unless hopping; can live up to 9 years and secretes poison on skin to deter many predators; mostly invertebrate prey are located visually followed by lunging toward the prey while extending its large sticky tongue to catch and bring it into the mouth; they produce a simple repeated plinking sound during breeding season or when threatened.
Coastal Tailed Frog (Ascaphus truei): found in coastal and damp forests from Mendocino and Humboldt Counties north to British Columbia; small ‘toad-like’ frogs of 1-2 inches (2.5-5 cm) in length, with rough splotchy-patterned skin reflecting colors and patterns of its surroundings (often brown color base); long fingers with tips hardened to serve as claws to help in crawling among stream bottoms and rocks; males have a ‘tail’ extending from the body that serves as a copulatory organ; lungs are reduced in size (to decrease buoyancy so they can move around more easily in underwater substrates) and they respire mostly through the skin; they are mostly nocturnal and most active spring to autumn; they live up to 20 years and defend themselves by jumping into water, tucking in their limbs to dive down quickly on their way downstream away from danger; they do not have vocal sacs and do not make sounds; they eat a wide range of invertebrates typically along stream banks.
Sierran Tree Frog (Pseudacris sierrae): ranges from central California north to the Humbolt County coast, inland to Nevada and Idaho and up into British Columbia; they are found in a variety of habitats, sometimes far from water (outside of breeding season which requires water); even though its called a ‘tree frog’, it is mostly a ground-dweller; small bodied frog, adults are not larger than 2 inches (5 cm) snout to vent; relatively large head and eyes with a characteristic dark stripe running to each eye from the nostrils out to the shoulders; typically green or brown in body color, but coloring can vary quickly to match background of environment (e.g., in response to moving into dark or light locations); active in both day and night, unless during a dry period in which nocturnal activity predominates; produce loud vocal sounds including a two-part ‘rib-it’ (or ‘krek-ek’) used to warn other males and a one-part attraction call for females; feed on flying insects, located visually followed by lunging and unleashing its large sticky tongue to catch and move into mouth.
Northern Red-legged Frog (Rana aurora): found in coastal and coast range forests, grasslands and streamsides in Mendocino County north to British Columbia; adults are 2-3 inches (4-8 cm) long from snout to vent; typically reddish-brown smooth skin with small black flecks and spots on back and sides, a cream-colored chest and throat marbled with dark gray, but with red-colored hind legs and lower belly; typically a ‘pond frog’ but may also be found in damp places far from water; their vocal call consists of a weak sound of 5-7 notes (‘uh-uh-uh-uh-uh-uh’) most often delivered underwater (so it’s very difficult to hear); typical of most frogs, they locate a variety of invertebrates by vision, followed by use of their sticky tongue to catch and move into mouth; can live more than 10 years, and defend themselves by blending into their environment while remaining still or quickly leaping into brush or water to escape.
Foothill Yellow-legged Frog (Rana boylii): found in coastal, coast range, and Sierra Nevada forests and chaparral in California and southwest Oregon; adults are 1.5-3 inches (4-8 cm) long with grainy (rather than smooth) skin of a gray, brownish or olive color with mottled patterns; the undersides of the rear legs and abdomen are yellow; typically found near or in water, active during daylight; feeds on flying insects, grasshoppers, and several other types of invertebrates; they locate their prey visually, followed by capture using a quickly released sticky tongue that then takes it to its mouth; their vocal call is typically delivered under water, so is rarely heard; they defend themselves by diving to bottom of water or use of cryptic coloration and markings to blend in with the stream substrate; according to local studies by Dr. Sarah Kupferberg from U.C. Berkeley, the once large populations of this species across California have shown concerning declines, possibly due to habitat alterations, agricultural pesticide use (frogs readily absorb many chemicals through their permeable skins), and predation by the invasive non-native Bull Frog (Lithobates catesbeianus)—the local North Coast populations, however, appear to be okay for now, a stronghold for the Foothill Yellow-legged Frog.
American Bullfrog (Lithobates catesbeianus): largest frog inhabiting North America and distributed throughout California as an invader that originated from east of the Rocky Mountains; they are voracious eaters and will eat just about anything they can swallow, including other frogs, lizards, snakes, fish, and small mammals; adults are 4-8 inches (9-20 cm) long snout to vent, typically with light green to olive green coloration on their back and sides along with dark spots and blotches; undersides are often cream to yellow; they are rarely found far from water and are active both day and night; they make loud, low-pitched sounds often described as “jug-o’rum”, among other calls; they prefer warmer temperatures compared with many California native frogs, so they are typically not found in mountainous environments—indeed, their natural barrier to western expansion appears to have been the Rocky Mountain range prior to human-caused introductions.