REPTILES IN HERCULES
First vertebrates to live
completely terrestrial existence beginning about 250 million years ago.
Development
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.
Characteristics
Dry skin covered with scales.
“Scales” are actually folds and pleats in the epidermis, unlike fish scales,
which
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).
Reproduction
Wide variety of reproductive
strategies. In all reptiles fertilization is internal, resulting from
copulation.
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.
Conservation
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
Classification
Reptiles
listed are classified as follows:
Order
Squamata
Suborder Sauria:
All
lizards, with or without legs
Suborder
Serpentes:
All snakes
LIZARDS
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)
Size:
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.
Habitat:
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)
Size:
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.
SNAKES
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.
Local subspecies:
California King Snake
(Lampropeltis
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
southern
Habitat:
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)
Local subspecies
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.
Local
subspecies
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.
Local
subspecies
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.
Local
subspecies
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.
GLOSSARY
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.
