REPTILES IN HERCULES
First vertebrates to live
completely terrestrial existence beginning about 250 million years ago.
of a shelled egg allowed for development of the young away from water source. Keratinous scaly
skin offers protection from desiccation and allows reptiles to live in less restricted habitats than amphibians.
Also conserve water by concentrating liquid wastes in their bodies. They are able to tolerate high concentrations
of waste in their bodies and release urinary wastes in a semisolid form similar to bird droppings. Although not
the best loved, they are among the most successful groups of animals in terms of diversity and variety
of habitats. Well over 6,000 species live in all but the coldest places on the earth. Some groups, such as the
crocodilians have survived unchanged for over 150 million years.
Dry skin covered with scales.
“Scales” are actually folds and pleats in the epidermis, unlike fish scales,
grow out of the dermis. Scales allow smooth movement through grass, sand and rock piles; shape and color aid
in camouflage and are important in the mating and territorial displays of some species. Claws on toes. Eggs
with a flexible, leathery shell. At least one lung, as these are air-breathing animals. Ectothermic (cold-blooded).
Adjust their behavior to maintain a constant body temperature. Most of the time they are probably as warm
blooded as most mammals. Often seen basking on rocks or logs but quickly move into the shade if temperatures
go too high. A regulated temperature aids in digestion, increases metabolic rate, mobility and alertness. Survive
extremes of heat or cold by retreating underground. Their slow metabolism reduces the need for food.
Desert species estivate in burrows or adopt primarily nocturnal habits (desert tortoise and rattlesnake).
Wide variety of reproductive
strategies. In all reptiles fertilization is internal, resulting from
Some species lay eggs in warm, moist sand or soil (oviparous); some bear live young after the
eggs have ruptured inside them (ovoviviparous); and some bear live young with no egg development
at all (viviparous).
Females of some species can store sperm for long periods. This allows them to delay fertilization if necessary. Recent advances in the science of radio telemetry have allowed scientists a much closer look at the habits of these very secretive animals. How they hunt, eat, migrate and reproduce can now be studied in greater depth. Long-term studies of a subspecies of western rattlesnake have revealed that the females protect their young for some time after birth. It seems likely that new revelations will continue to challenge our assumptions and change the way we look at these animals.
Because of their beautifully
marked and durable skin, many species worldwide are over-hunted. The pet trade
has also had a detrimental effect on some wild populations. As a group reptiles
are among the most feared and misunderstood animals on the planet. Many are simply
killed out of ignorance or fear. In our area habitat destruction, especially of
wetland areas, is a factor in the decline of native species. Predation by wild
pigs has reduced populations of egg laying snakes (such as gopher and king
snakes) in some parts of
Reptiles listed are classified as follows:
Suborder Sauria: All lizards, with or without legs
Suborder Serpentes: All snakes
Size: 5-9" Snakelike burrowing lizards commonly found in areas of sand or loose soil. Silvery legless lizard (Anniella pulchra pulchra) is the local subspecies. Silvery above with dark stripe down the middle of back and dark striping on sides. Yellow belly. No external ear openings; blunt snout and tail are well adapted for burrowing lifestyle. Tiny eyes but eyelids are discernable. Smooth scales. Nocturnal.
Habitat: Sand dunes, gravel banks of streams, also leaf litter in woodlands.
Reproduction: Viviparous. Mating season May to June. 1-4 young born September to November.
Food: Insects and their larvae, spiders.
Coast Horned Lizard (Phrynosoma cornatum)
Size: 2 1/2-4" Yellow, brown, reddish, or gray. Wavy dark blotches on back, pair of large dark blotches on neck. Light colors of cream, beige, or yellow below. Two horns at the back of the head are longer than the others. Commonly called horned or horny “toad” because of its stout, squat appearance. Slow moving and (often to their detriment) easy to catch. Camouflage is an excellent first defense as their colors blend well with the semi-arid habitat they prefer. Will inflate bodies with air and stab with horns if harassed. Rather dramatic defense of shooting blood from their eyes is reserved for foxes and coyotes. Diurnal.
Habitat:. Chapparal, grassland, coniferous forests and broadleaf woodland. Need brush for cover, open areas for sunning and fine loose soil with lots of ants and other insect prey.
Reproduction: Oviparous. Clutches of 6-21 eggs are laid from April to June, hatch July to September.
Food: Insects, especially ants. Poor survival rate in captivity because of this specialized diet.
Northern Alligator Lizard (Gerrhonotus coeruleus)
3-8" Local subspecies is San Francisco
Alligator Lizard (Gerrhonotus coeruleus coeruleus). All
alligator lizards have slender bodies with long semi-prehensile tails that are
used to varying degrees to assist in climbing after prey. Very short limbs and
long tail may cause them to be mistaken for snakes. As with the legless lizard,
if the animal you are looking at can blink it’s not a snake. Dorsal and ventral
scales are reinforced with bone, a distinctive fold on each side of the body is
formed in a strip of granular scales that separate the larger scales on the
back and belly. These lateral scales are more flexible and allow for breathing,
and the accommodation of food, eggs and/or developing embryos. Eyes dark or
dark around the pupils. Gray, olive, greenish or bluish above.
Reproduction: Viviparous. Unlike the Southern Alligator
Lizard, the Northern bears live young. Mates in April. 2-15. Young are born in 7-10 weeks
Food: Insects, ticks, snails, millipedes, spiders.
Southern Alligator Lizard (Gerrhonotus multicarinatus)
Size: 3-7" Local subspecies is California Alligator Lizard (Gerrhonotus multicarinatus multicarinatus). Primarily brown, gray, reddish, or yellowish above. Red blotches on back. Top of head often mottled. Eyes pale yellow. Usually well defined dark crossbands on back and tail. Young have broad stripe of tan, reddish beige or gray from head to the end of tail. Barred sides. Adult males have a larger, more triangular head than females.
Habitat: Grassland, chaparral, oak woodland. May enter water to escape enemies. Woodpiles are a favorite hiding place. Good climber. Highly adept and aggressive hunters, these lizards will eat almost anything they can catch and subdue. Can inflict a nasty bite if handled, will also exude foul smelling musk (feces) in effort to discourage predators. Can also shed tail if necessary. Diurnal.
Reproduction: Oviparous. 1-3 clutches of 5-20 eggs laid from May to June.
Food: Slugs, insects, centipedes, scorpions, spiders and their egg cases (including black widow), lizards, small mammals, eggs and young of birds.
Western Fence Lizard (Sceloporus occidentalis)
2-6" Possibly two local
subspecies: Northwestern Fence Lizard (Sceloporus occidentalis
occidentalis) and Coast Range Fence Lizard (Sceloporus
occidentalis bocourti). Commonly called “blue-belly” or “swift”,
these are probably the most common and commonly seen lizards in
Habitat: Has adapted well to human habitation. Makes use of woodpiles, decks, fences, and buildings as well as the chaparral, grassland and woodland that are its natural habitat. Prefers such areas with rock outcroppings or fallen trees. Principal methods of defense are camouflage, speed, and the ability to leave a briskly wiggling portion of its tail behind while the lizard makes its escape. Care should be taken when handling these animals as the tail is quite easily shed. It will eventually grow back but in the meantime the lizard is without this very effective defense. Diurnal.
Reproduction: Oviparous. 1-3 clutches of 3-17 eggs laid between April and July. Hatch July-September.
Food: Insects of various kinds, spiders.
Western Skink (Eumeces skiltonianus)
Size: 2-6" Local subspecies is the Skilton skink (Eumeces skiltonianus skiltonianus). Skinks in general have long cylindrical bodies and tails covered with smooth scales containing bony plates (osteoderms). Very small legs and sinuous method of locomotion. Local variety has a broad brown stripe down the back, edged with black and bordered on each side with a beige or white stripe. Red or orange color appears on the head, chin and parts of the tail during the breeding season. Juveniles have bright blue tails. These may serve to decoy predators to the tail area which can be shed and/or to curb the cannabalistic tendencies of adult males.
Habitat: Grassland, chaparral, mixed forest. Prefers areas with some moisture and good plant cover. Diurnal but shy. Will bite if handled roughly.
Reproduction: Oviparous. Mates May-June, clutch of 2-6 eggs is laid June-July in burrow or under rocks. Tended by female until hatching in July-August.
Food: Insects, spiders and sowbugs.
Garter Snakes (Thamnophis spp.)
Several varieties of these familiar snakes are found in the area. Common in streamside areas and near ponds. Terrestrial variety can be found far from water, where it uses plant cover for protection. Common name comes from the striped varieties resemblance to an old-fashioned sleeve garter. Sometimes called “garden” snakes, either a corruption of garter or because they have made their home in someone’s backyard. Usually striped but can be speckled or blotched. Patterns of stripes can vary from species to species. Generally slender and small in size but some varieties can reach 5 feet in length. Identification can be difficult, but as in some cases essential. The San Francisco Garter Snake, a local subspecies of the Common Garter Snake, is a federally listed endangered species. Collecting this snake or disturbing its habitat can result in prosecution and a heavy fine. All garter snakes are truly viviparous. Females actually have a rudimentary placental attachment to their young which is very unusual in snakes. From 4-85 young (depending on the species) are born from May through October. Kills by seizing and engulfing prey.
Common Garter Snake (Thamnophis sirtalis)
Size: 2 1/2-4 feet. Most widely distributed snake in
Habitat: Grassland, woodland, chaparral, and forest. Prefers to be near water, making use of ponds, ditches, streams or marshy meadows. Enters water freely for food and protection. Diurnal.
Reproduction: Viviparous. 3-85 young born May-October.
Food: Fish, toads, frogs and salamanders (and their larvae), birds, small mammals, reptiles, earthworms, slugs and leeches. One of the few predators of the highly poisonous Pacific newts (Taricha spp.).
Gopher Snake (Pituophis melanoleucus)
Size: 2-8 feet. Large yellow or cream colored snake with black brown or reddish brown dorsal blotches. Dorsal scales are keeled, giving a rough appearance to the skin. Dark line across the head in front of the eyes and from behind the eye to the angle of the jaw. White to yellowish below, often spotted with black.
Habitat: Very common in grassland areas around rodent burrows and in open brushland. Good climber and burrower. Diurnal except during very hot weather. When threatened, it can hiss very loudly and will sometimes vibrate the tip of its tail. This rattlesnake mimicry serves the animal very well with predators other than humans. It has led to the death of many snakes at the hands of those who kill first and look for rattles later. Kills prey by constriction.
Reproduction Oviparous. 1-2 clutches of 2-24 eggs laid June through August.
Food Rodents, rabbits, birds and their eggs, and occasionally lizards and insects.
Common King Snake (Lampropeltis getulus)
Size: 2-6 feet.
California King Snake
getulus californiae). Genus name means “shiny skin” because of the
animal’s very smooth scales. Can be banded or striped with intermediate
variations. Banded snakes are more common here, striped pattern more common in
Reproduction: Oviparous. 2-24 eggs laid May-August.
Food: Snakes of all kinds, lizards, frogs, birds and their eggs and small mammals.
Racer (Coluber constrictor)
Western Yellow-bellied Racer (Coluber constrictor mormon.)
Size: 20-73". In this area usually under 36 inches. Slender, fast moving snake with broad head, slender neck and large eyes. Smooth scales plain brown, olive or bluish above and unmarked pale yellow below. Young have brown saddles on the back, smaller blotches on the side. Sometimes confused with young gopher snakes.
Habitat:. Favors open areas such as meadows, grassland and open chaparral. Prefers grassy places with rocks and logs or other basking sites used by lizards (a favorite prey). Is usually found on the ground but occasionally climbs trees or shrubs. When hunting, tends to hold its head high and move swiftly through grass or plant cover. Despite its species name, it is not a constrictor. It is quite difficult to catch and bites readily if annoyed. Also mimics rattlesnake by vibrating its tail in grass or dry leaves. Diurnal.
Reproduction: Mates April to late May. Oviparous. 3-7 eggs laid June-August.
Food: Lizards and other reptiles, small mammals, insects and frogs.
Western Rattlesnake (Crotalus viridis)
Size: 1-5 feet.
Northern Pacific Rattlesnake (Crotalus viridis oreganus)
In this area primarily brownish or olive above. Large oval or hexagonal dark blotches bordered by white scales. Light stripe extending from behind the eye to the corner of the mouth. Well defined dark tail rings. Young have light yellow tail. Scales keeled, giving skin a rough appearance.
Like all pit vipers, a heavy bodied snake with a slender neck and triangular shaped head. Loreal pits located between the eye and the nostril are heat sensitive and assist in the location of prey. The only venomous snake native to this area. Hollow, retractable fangs are recurved along the inside of the jaw. When the mouth is opened they swing forward, the prey is struck and venom injected. The distinctive rattle is made up of flattened, interlocking segments of keratin. A new segment is added each time a snake sheds. Since many factors affect the rate at which a snake sheds its skin, it is not possible to tell a rattlesnake’s age by counting the rattles. Young snakes may shed 3 or 4 times a year, an adult once or twice. Rattles also break off. Young rattlers have a noiseless “button” until their first shed. For this reason they are sometimes more dangerous than adults. They are not more venomous or more aggressive, just less experienced and unable to warn us of their presence. Snakes are not active during cold months. May retreat to communal dens or rodent burrows to hibernate.
Habitat: Chaparral, woodland, around barns and rodent burrows, rocky outcrops, ledges and rocky stream courses. Diurnal, crepuscular during hot months.
Reproduction: Ovoviviparous. 1-25 (often 4-12) young born July-October.
(Western Rattlesnake continued)
Food: Small mammals such as mice, ground squirrels, and rabbits, nestling birds. Lizards are a favorite food of young snakes. Their highly effective venom allows rattlesnakes to kill and eat much larger prey. Prolonged and possibly damaging physical contact with sharp toothed prey is avoided. Venom effectively begins the digestive process by breaking down the blood vessels of the victim.
Ringneck Snake (Diadophis punctatus)
Size: 8-30 inches.
Pacific Ringneck Snake (Diadophis punctatus amabilis)
Slender, brownish olive or nearly black snake with dark head and distinctive orange-red band around the neck. Ventral surface yellow-orange to red. Color is more intense on underside of tail. Smooth scales.
Habitat: Prefers moister areas in woodland, forest, grassland, chaparral, and gardens. Seldom seen, often found under rocks, rotting logs or boards. If disturbed will emit a foul odor. Will also display the brightly colored ventral surface of the tail by coiling it in a tight spiral. Sometimes gather together in protected sites. Females often lay eggs in a communal nest. Diurnal.
Reproduction: Oviparous. 1-2 clutches of 1-10 eggs laid June through July.
Food: Slender and other salamanders, small frogs, lizards, small snakes, slugs and worms. May be venomous to smaller prey but not considered a danger to humans.
Rubber Boa (Charina bottae)
Size: 14-33 inches.
Pacific Rubber Boa (Charina bottae bottae)
A stout, smooth scaled, rubbery looking snake. Sometimes called the two headed snake because the tail is similar in shape to the head. Large symmetrical plates on the top of the head. Pale brown to olive green above, yellow or cream below. Young are pinkish to tan above, belly light yellow to pink. Adult males have tiny “spurs” on either side of the vent. These are the vestiges of hind limbs and are often seen in members of the boa family. In females spurs are reduced or absent.
Habitat: Grassland, broken chaparral, woodland and forest in and beneath rotting logs, under rocks and woodpiles, under the bark of dead trees. Excellent swimmer, burrower and climber. Burrows into damp sand, hollow rotting logs or forest litter. Crepuscular and nocturnal. Docile and long - lived in captivity.
Reproduction: Viviparous. 2-8 young born August through November.
Food: Small mammals such as young mice and shrews, birds, salamanders, and snakes. Kills by constriction.
Amplexus- Sexual embrace of a male amphibian in which the forelimbs of the male clasp the female from behind in the chest or waist region.
Cloaca- The common cavity into which the intestinal, genital and uninary tracts open in vertebrates such as fish, reptiles, amphibians and birds.
Crepuscular- Becoming active at twilight or before sunrise.
Desiccation – To dry out completely or dehydrate.
Estivate – To pass the summer in a dormant or torpid state.
Isopod – Any numerous crustaceans of the order Isopoda, characterized by a flattened body bearing legs.
Keratin – A tough insoluble protein and the chief constituent of hair.
Oviparous – Producing eggs that hatch after laying
Ovoviviparous – Producing eggs that have a well developed shell but which hatch before or at the time of laying, as in certain reptiles.
Vent – The opening on the surface of the body of the cloaca is the common chamber into which intestinal, urinary and reproductive canals discharge.
Viviparous – Bearing live young with no egg development at all.