Black widow spider Most common poisonous spiders
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Most common poisonous spiders The United States is home to three types of poisonous spiders: black widow, brown recluse and tarantula A black widow spider's venom is classified as a neurotoxin, which means it is poisonous to the neryous system whereas the venom of a brown recluse spider causes necrosis - essentially a breakdown of skin and tissue. The tarantula injects venom into its prey through the hair on its body and legs, causing a severe allergic reaction that sometimes leads to anaphylactic shock. Black widow spider The black widow sprder is easy to identiff because of its black shiny body with red- to orange- colored markings visible on its underside. This spider lives in dark places such as trash cans, attics, closets, and woodpiles and is found in parts of Califomia and southern parts of Canada Black widows have also been known to hitch a ride with shipments of fresh fruit and make an appearance in other states and other Canadian destinations. Although death via a black widow spider bite is uncommon, its bite can be serious. Once bitten, the victim will notice apainful pale area of skin surrounded by a red ring. \Mithinthe first few hours, severe cramping may occur in the shoulders, baclq abdomen and thighs. In addition, the spider's bite may cause irching, sweating, headache, weakness, nause4 vomiting, increased blood pressure and breathing difficulties. Although most reactions to a black widow spider bite are not severe, medical attention is paramount if breathing is compromised and muscle cramps develop. Young children, the elderly and individuals with high blood pressure are more prone to develop severe adverse reactions to a black widow bite. Brown recluse spider The brown recluse spider is also feared for its painful bite and subsequent physical reactions. This spider is native to Oklahom4 Kansas, Texas and Mississippi but can surface anywhere thanks to modern transportation. The brown recluse spider prefers dark, quiet surroundings and doesn't venture out into open a.reas very often. It grows to a half-inch in length and its body is light brown in color. Ifs often referred to as the violin or fiddleneck spider because the markings on its back resemble a violin. Unlike other spiders, the recluse has six eyes instead of eight and the lower part of its body has no markings. A brown recluse spider's bite will leave a wound resembling a bull's eye; ared ring with a blister in the center. The blister will break giving way to an ulcer ffie sore that will scab over. In some cases, the ulcer will get larger and affect the underlying skin and muscle tissue and be accompanied by severe pain. Within 24 to 48 hours, an itchy, red rash will appear and may be accompanied by chills, fever, muscle aches, nausea and vomiting. In some instances, hemolytic anemia, which is a condition where red blood cells are destroyed, may occur.
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Although there is no current comprehensive list, Oregon probably has at least 5oo
species of spiders. Most spiders are small and rarely encountered, often living in forest
Iitter, rock crevices, rotten logs, and similar habitats. There are a dozen or so that are
frequently found in or near residences. Although all spiders have fangs and virtually all
have venom, only a few are either krrown or thought to have bites harmful to people. The
rest are harmless (at least to people), feeding on a wide variety of insects and other
invWhen a person gets too close to a spider, they may be bitten. Spiders bite people in self-
defense. They otherwise have no interest in biting something they can't eat, particularly
something that is likely to squash them. Normally people are not bitten unless they actually come
in contact with a spider. People may be biuen when they place a hand on a spider (for instance,
upon one sheltering in a wood pile or behind fumiture or some boxes) or if they put on clothing
or footwear that has a spider sheltering in it. Even if a spider bites you there is chance that it will
be a"dty" bite, meaning there is no venom. If you do receive a venomous bite, the amount of
toxin will vary from spider to spider, even bites within the same species. According to at least
one arachnologist, spider bites are not very common. You are not likely to receive more than one
or two bites in a lifetime.
The black widow, the hobo spider, and the yellow sac spider are of interest in Oregon because
they occasionally enter homes and may bite people. Black widow bites should always be treated
as potentially serious. Reactions from the bites of hobo spiders and yellow sac spiders are not
well documented. Recently, questions have been raised as to whether hobo and yellow sac spider
bites are truly dangerous. Some researchers believe that the symptoms associated with presumed
bites from these spiders really have other causes. Since no one knows for sure, we believe it is
best to treat suspected bites from hobo spiders (and to a lesser degree, those from yellow sac
spiders) as potentially serious. A fairty well known venomous spider that occasionally bites
people, the brown recluse, Loxosceles reclusa, does not occur in Oregon, despite reports to the
contrary. Most spiders in Oregon, even those most likely to be found in homes, are not known to
be dangerous. Rarely, serious systemic ("allergic") reactions from spiders can occur.
If a spider bites you try to save it for identification. Having the spider identified will help to
determine what type of treatment you need. Spiders can be brought to or mailed to identifiers at
ODA as detailed below.
Please follow these tips on saving and mailing a spider for identification:
a If possible don't crush the spider.
a To kill the spider either place it in a container and put it in the freezer or submerge the spider in rubbing
alcohol in a small leak proof container.
To prepare a frozen spider for the mail be sure the spider is kept in a container with tissue paper to prevent
it from rattling around and getting broken. Allow for a lot of airflow in the container if the-spider iJnot
completely dry because it will rot (poke some holes in the container if necessary). Spiders mailed in
rubbing alcohol need to be in leak proof containers. All spiders mailed need to be incrush proof containers
(such as film canisters orpill bottles).
Do not send live spiders to identifiers in containers tlat you can't see through the identifiers are not
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expecting a live spider so they could be bitten ifthey open the container.
r Black Widow Identification Key: The Red Hourglass
This is the distinctive sign of the black widow - a bright red hourglass marking on the
animal's ventral side (the "bottom" or underneath)" It's your surest guide to lllack Widow
identification -- no other spider has it. In the natural world, bright red, orange, or yellow
markings are universalll used to signiff protection by venom or caustic ehemicals in the
insect's haemoll-mph, or blood. This, in effect, tells everyone: "stay arvay from me, or you'll
be sorry." But the classic hourglass shape is only one morph that spiders in the Black
Widow's genus display. Here are a couple of other variations that still sen,e the purpose of
warning away predators -- including you.
of the genus of spiders known
The Hobo spider (Tegenaria agrestis) is a member
confused with the Australian funnel-web
coltoquially as funnel web spiders, but not to be
whose bites are generally considered to be
spider. It is one of a small number of spiders
structure of silk sheeting and
medically significant. Individuals construct a funnel-shaped
prey insects to brunder onto their webs. Hobo
Iie in wait at the sman end of the funnel for
spiders sometimes build their webs in or around
human habitations' This species of
spider has a reputation for aggressiveness, due
to its poor eyesight' They will normally
crushed or squeezed. The spider's venom
avoid contact with humans unless accidentally
possibly, necrosis
is strong enough to cause considerable local pain and,
W
Yellow SaC SpiderS vary in length, but average 6mm (about the size of a
nickle). They have no distinctive markings except a brownish tint to the mouth and eyes.
Their legs are slightly longer than the body, and the first two legs are longer than the oth-
ers. All the legs appear to have dark "feet," which is caused by an aggregation of dark,
dense hairs toward the tip of their legs. Except for sex characters, males and females
appear similar, with males being a little smaller. Scientists observed that the spider varied
in color according to the food it ingested. After eating a bright-green lepidopteran
caterpillar (moth or butterfly larvae), the spider became noticeably green. [mmature
spiders that fed on red-eyed fruit flies assumed a rosy hue, and those that fed on common
house flies became gray
Spider Bites: Hobo or Brown Recluse?
There,s a cofirmon myth among Pacific Northwest residents
about spider bites, and it's this:
recluse'
Many venomous spider bites come from the nasty, dangerous brown
are extremely rare in oregon
Recent studies, however, have proven that brown recluse spiders
and washington and aren't to bL blamed for the majority of
bites. The real culprit? The hobo
spider.
The Reality
Washington State
According to research done by many difterent organizations, including
all bites attributed to brown
University and a number of pest management professionals, almost
recluses actually came from hobo spiders'
Why the Mistake?
referenees physicians
The main reason most bites are misdiagnosed is because most diagnostic
and brown recluse' Since most
use to identifu spider bites offer only two options: blackwidow
complications in
all spider bite symptoms are similar- localiied tissue deterioration, ulceration,
the nervous system - it's difficult to determine
just what kind of spider caused the bite' Only
and are also quite
recently have hobo spiders - which ire coflrmon in the Pacific Northwest
venomous - been included in diagnostic references'
How to Tell the Difference
is to exrymne the pest
The only surefire way to determine whether you have a hobo spider
spider infestation can bring a
through a microscop". Corr..*.d homeownirs who suspect a hobo
spideisample to Eden Pest, whose entomologists will ID it at no cost.
cold packs to
If you believe you have been bitten by one, keep the area elevated and apply ice or
Once your bite has been
reduce inflammation. If the reaction worsens, siek medical attention.
treated, contact a pest management professional immediately. A
Portland pest control company
get rid of them.
can accurately deGrmine what type of spiders you have and how to
reliable sources. Just
What do they look like? Good question. I found 9 different photos from
one here but rarely
know that Brown Recluse a." not in Oregon. It is always possible to transport
do they survive our climate.
r Treatment of spider bites
The frst rule to treating a spider bite is to clean the bite, apply ice immediately and elevate the
bite area. Bites from any of these three spiders should be evaluated by a medical professional.
If the bite is mild, treatrnent includes analgesics, antihistamines and antibiotics and Antivenin. A
black widow bite may require a muscle relaxant inhoduced through intravenous or high blood
pressure medication to guard against elevated blood pressure caused by the venom.
A brown recluse spider bite may require hospitalization if hemolysis (the destruction of red
blood cells leading to the release of hemoglobin into the blood plasma) occurs and the tissue
surrounding the bite starts to die. A tarantula's bite can be treated with antihistamines or
glucocorticoids to ease the adverse symptoms. With all spider bites, a tetanus shot is
recommended.
Take precautions and avoid getting a spider bite
Prevention is the key to avoiding a painful spider bite. Avoid areas in which spiders dwell and if
your path crosses a spider's web, be careful not to disturb it or provoke the spider. Be extra
cautious when using an outhouse - spiders often find refuge in the lowly outdoor commode.
Oregon's 15 Native Snakes
Life History
Observing Snakes
Prwenting and Addressing Conficts
Removinp Tiapping and Relocating Snakes
Recommended Con servation Actions
Attracting Snakes
Injured Snakes
Oregon's Snake Species Status
Nonnative, Invasive and F,xotic Snakes
Scientific and Education Peirnits
Public Health C-oncerns
More Information
Common Garter Snake (Thamnophis sirtalis)
Al Sr John photo
OREGON'S 15 NATTYE SNAKES garter snake may be mildly toxic to amphibians and other small animals.
Snakes ue among the most misunderstood of animals. Myths abound: If disturbed, a garrer snake will try to escape, but may strike or bite if
]Most snakes are poisonous, snakes can jump mo feet, snakes will not cross cornered or someone gets too close or tries to pick it up. Other than
a rope, snakes oniy strike when coiled and snakes travel in pairs. All of attempting to flee, garter snakes best defense againstwould-be predatois is
these myths are untrue as are many of the others that circulate, but in the the secretion of a foul-smeiling fluid ftom post-anal glands that is released
absence of information, people often believe them. In this fact sheet, we during high sffess events such as capture and handling.
provide facts about Oregont native snakes that dispel myths and promore a Garter snakes are highly beneficial in that rhey feed on slugs, snails and
better understanding of these wonderfirl, ecologically important animals. other garden pests. Small garter snakes ear earrhworms and slugs rvhile the
In general, snakes are relative[ inactive except when looking for a spot diet of larger snakes includes amphibians, small rodents, nesding birds and
in the sun or shade or when hunting. Like other reptiles, snakes are fish. Garter snakes give birth ro live young. Following are the four species
ectotherms meaning their body temperarure is regulated directly by the found in Oregon.
surounding temperature. They generally have poor eyesighr and hearing The Common Garter Snake (Ihamnopltis sirtal;s)ts the most widespread
uraste"
but have a well-developed sense of smell and the ability to rheir and frequently encounrered snake in Oregon. h is found from coastal and
imme&ate environment. To do this, they flick their rongues to pick up mountain forests to sagebrush deserts and baclgrard gardens. Coloration
gaseous particles out ofthe air and into a sensing organ (|acobsent organ)
and patterning is variable; genelally, it has a cream or yellow dorsal stripe
in the roof of their mouths. This helps them sense danger, find mates and running lengthwise down its body, red blotches along the sides, and a
locate or track prey.
grayish-blue, green, yellow or black underside.
There are 15 native snake species in Oregon. Of these, only the \flestern k averages 18 to 36 inches long. In the easrern parr ofthat srare, it
Rattlesnake has poisonous venom that is dangerous to humans. rypically occurs close to water. There are two sub-species in the state;
The Red-spotted Garter Snake (I r. concinruas),which is found only in the
Garter Snakes Mllamette Valley and the Vallq, Garrer Snake (T s. ftchi)which occurs
throughout Oregon except for tle northern coastal area and arid central
There are four species ofgarter snakes. They inhabit a variery ofhabitats,
portions of the state.
including suburban areas. Their name comes from their resemblance to
the design on garters once worn by men to hold up their socks. Garter
snakes are non-venomous and harmless ro humans, thou$ the saliva of a
Oregon Department of Fish and Wildlife
;lry,ffi
Pacific CoastAquatic Garter Snake (Thnrunophis atratus)
Simon Wray photo
The Pacific Coast Aquatic Garter Snake (Thamnophis a*atus) is found
along rivers in the southwestem part ofthe state, as far north as the
UmpquaValley in Douglas County. It stays close to water and its diet is
Northwestem Garter Snake (Thamnophis ordinoidts) comprised mostly of fish and amphibians (adults and larvae). To escape,
A1 St. John photo this snake wiil dive beneath the surface of the water and hide under rocla.
Adults average 18 to 33 inches long and usually show a pattern over olive-
The Northwestern Garter Snake (Thatnnophis ordinoidu)occurs in coastal brown to gray background color. Dorsal stripes can be absent; ifpresent are
and mountain forest habitats west of the Cascades. It is most commonly typically a light yeilow.
found in grassT-brushy ueas and in weedy sections of suburban baclg,uds
and city parla. It is more slender than other gafter snakes and reaches two -;k'-
feet at maturity. The Northwestern Garter Snake is the most variable in *{
*r:.
color and patterning ofall Oregon snake species. lhe dorsal stripe can be
absent or resplendent in various shades and colors, such as red, orange,
greenish yeliow, tan, blue or rvhite,
'Western
Terrestrial Garter Snake (Thamnophis elegans)
Al St. John photo
Gopher Snake (Pituophis catenifer)
The Western Terrestrial Garter Snake (Tltamnophis elegans)occurs in a
Simon \flray photo
wide variety ofhabitats except along the centra.l and north coastal zones,
much of the east slope and crest of the Cascades, and in a smallportion The Gopher Snake (Pituophis catenifn), also known as the bull snake, is
of central Oregon. Despite its name, this snake spends a lot of time in the a constrictor, preying primarily on small rodents. It is often mistaken for
water. It is usually gray-brown or black, with a dark, checkered pattern a ratdesnake due to its coioration and its impressive ability to mimic a
between yellow stripes although identification can be difficuit, because rattlesnake by flamening its head, coiling, striking and hissing loudlli To
there are three sub-species recognized in Oregon, ali varying in coloration: complete the pseudo image of a rattlesnake, a gopher snake wiil vibrate the
the Coast Guter Snake (7. e. tenratris), found in the far southwest corner tip ofits tail. Althou$ it is not poisonous, this aggressive behavior leads
of the state; the Mountain Garter Snake, found throughout the Wiliamette many to believe that it is a ratclesnake. The easiest way to tell a gopher
Valley and southwest Oregon; and the'Wandering Garter Snake (T e. snake from a rattlesnake is to look at the taii. Gopher snake tails come to a
uagrans),found east of the Cascade Mountains. Nearly black forms occur fine pint and lack rattles. Ranlesnakes have an obvious "raftle" that comes
in some areas. Adults are 18 to 43 inches long. to a blunt end.
Oregon Department of Fish and Wildlife
The Gopher Snake is found statewide excepr along the coast and above yellow belly. It is thinner than a garter snake ofcomparable size and has
6,000 feet in the Cascades. k prefers waim, dry habitats including deserrs, larger eyes. The Racer is well named because it is extremely fast. It holds its
grasslands and open woodlands. It is a robust snake, measuring *uee to six head and neck above the ground when hunting and may climb into shrubs.
feet in length, and has dark blotches against tan along its back. Like most Its diet consists primarily of small mammals, lizards, frogs and insects,
oforegont snakes, gopher snakes have round pupils. The only snakes wirh
elliptical (cat eye) pupils are night snakes and ramlesnakes. Gopher snakes
have a disdnctive dark facial srripe that passes tluough both eyes. There
aje mo sub-species of gopher snake in Oregon, the Pacific Gopher Snake,
found in the \flillamette Valley and sourhwesr Oregon, and rhe Great Basin
Gopher Snake, found east of the Cascade Mountains.
Striped Whipb nake ( Co lu b e r t am i atus)
Al St. John photo
The StripedWhipsnake (Calubu tamiatus)is acloserelative of the
racer, inhabiting brush and grasslands of eastern Oregon up to 2,000 feet
elevation. Either black or dark brown above, the sides ofthe whipsnake
each have a white or yellow stripe rvith a dark line or dashes in thl middle
of the stripe making it appear to be rwo light stripes on each side of the
body. Primarily a day-hunting snake, it ears lizards, snakes and small
mammals. Often exceeding five feet, it tail and an
is slender, has a long
Ni$t Snake (Hypsigbna chlomphaea) elongated head with large Like the racer, it willhunt with im head
eyes.
AI St. John photo held above the ground and often climbs into shrubs to pursue prey or
evade predators.
The Ni$t Snake (fupstglena thlorophaea)lnes in roclcy areas in easrern
Oregon and is rarelv seen because it hunts and moves at night. Night
snakes are relatively small, less than 20 inches long, have a row of 6rown
blotches down the back, a large duk blotch at the back ofthe head and
conspicuous copper-colored eyes with narow vertical or cat-like pupils.
Ni$t snakes fced largely on lizards, which they subdue with rhe help of
poisonous saliva delivered via grooves in their slighdy enluged back teeth
and worked into their victim by a chewing acrion.
Sharp-ailed Snrke (Contia tenuis)
Al St. John photo
The Sharp-tailed Snake (Corutia renais)is closeiy associated wirh dry
habitats such
as oak woodland; coniferous and pine forest; and chapanal.
It found in southwest Oregon from the Cascades ro the coasr,
is
throughout most of rhe $0'illamette Valley, and along the Columbia River
near The Dalles. lhe Sharp-tailed Snake is secretive in nature and leads
a largely subterranean existence or hides under logs, rocks and other
objects. hs principalfood source is small siugs. k is mosr commonly seen
Racer (Co lub er constrictor) during periods when slugs are acrive in the fall when the ground is wet but
Al St. John photo before it begins to freeze at night and in the spring beforJit becomes too
dry. k can also be found in irigated gardens, especially those that have
The Racer (Coluber constrictor/ occurs statewide except along the coast black plastic sheeting used ro conuol weeds. The Sharp-tailed Snake has
north of Port Orford and the cresr of the Cascades. It prefers warm, dry alternating crossbars ofblack and cream on its underside. A small snake,
open or brushy countrywhere it is often observed crossing roads. It ranger rarely ol'er a foot long,
it gets its name fiom a tiny spineJike scale on the
&om two to four feet long and is plain brown or olive above with a pale dp of its tail.
Oregon Department of Fish and Vildlifelhe California Mountain Kinpn*e (Lampropeltis zonata) is one o{
Oregon's most colorfulsnakes. h has a circular pattern of red, black and
creamy yellow bands separated by black. They average 20 to 30 inches
in length and occur mainly in the Rogue and Umpqua River valleys and
the Klamath Basin. A constrictor, the Caiifornia Mountain Kingsnake
eats other snakes, lizuds, small mammals and the eggs and nestlings of
birds. Jhese snakes ue often killed when people mistakenly r}ink they are
venomous coral snakes native to the southeastein U.S. and as far west as
Ring-necked Snake (Diadaphis ?anctdtal southein A,rizona.
Simon Wayphoto
The Ring-necked Sntke (Diadophis ?unctatal occurs in the drier puts
of southwestern Oregon, the \flillamette Valley and the lower Deschutes
River Valley and has been recorded along the Grande Ronde fuver and in
Hells Canyon. This snake is rwo-toned, with slate gray to green coloration
above with contrasting bright reddish orange or yellow below. A ring of
matching orange or yellow encircles the neck. \When alarmed, this snake
hides its head and coils the tail upward, revealing the bd$t underside. It
grows to thirry inches in length and eats salamanders, frogs, small lizuds
and snakes.
Common Kingsnake (Lamprop ebis gauk)
Ai St. John photo
The Common Kingsnake (Lanpropeltis gau@ is found in oak savannas,
Ground Snake (Sonora semiannulata) mixed pine-oak woodlands and brushy ueas in the Umpqua and Rogue
A1 St. John photo River valleys. This snake attains a length of almost four feet and has a
pattern of brown to black and cream to wliite circular bands. lhe Common
The Ground Sntke (Sonora semiannulata)reaches the northern limits of
Kingsnake feeds on avariety oflive prey, but is partial to other reptiles,
its distribution in Oregon with known populations along the Owyhee
particularly lizuds. These snakes ue known to eat rardesnakes and ue
River. It is one of Oregon's smallest snakes with adults averaging eight to
immune to the venom. The species can be quite excitable when initially
12 inches. Ground Snake coloration can be varied, but the most common
disturbed and may vibrate its tail, hiss or strike.
morph has alternating rows ofblack crossbands separated by a reddish
color. lrss common morphs include alternating black and white or black
and gray bands, or no bands and a reddish orange stripe running down the
back. lhe ground snake eats spiders, grasshoppers and insect larvae.
California Mountain Kingsnake (Lartpropehis zonata) Rubber Boa (Charina bouae)
Hodo Sondassi, USF![S, photo Al St. John photo
Oregon Department of Fish and Wildlifelhe Rubber Bor (charina botne)isa member of the familv that includes Ratdesnakes cannot spit venom.
some of the world's largesr snakes-including the boa.onst i.to, ,nd
While human deaths from raulesnake bites are rare, a do*or should be
anaconda. However, ir measures only 14 to 30 inches. It is olive-green, consulted immediately as a bite can be lethal.
reddish-brown or ran ro chocoiate-brorvn. It loola rubbery and hL a short,
Although venom is mosr often tlought of as a tlueat to humans, it is
broad snour and a short, blunt tail, giving it a rwo-headed appearance.
used in a number of beneficial wryr. For example, venom from Austrarian
The Rubber Boa is found in a wide variety of habitats indu&ng oak and
pine woodlands, grassy areas, brushy chapural and moist sandliueas along
tipans is being us".d to promore
clotting anditop excessive bleeding
rocky streams. Although seldom encountered, this snake.r, b. .ormon "
dunng surgery ol major rrauma. Additionalln ongoing research
fe_r
has demonstrated high potentialfor enzymes within snike ieno,
and has one of the widest distribution of any Oregon snake species. It to b.
used in the treatment of some cancers, stroke victims and neurorogicar
occurs starewide ex{ept along the coast north of Gos Bay, thi Cascade
conditions such as Parkinson's and Alzheimert diseases.
crest, a section of the Columbia Gorge and southern Harney Counry.
It eats small rodenrs, mostly mice end shrews, and is a goodswimmir,
burrower and climber. LIFE HISTORY
Food and Feeding Behavior
' snakes ue.predators and eat evariety of animals including earrhworms,
slugs, snails, insects, mice, voles, bird eggs and nesdings, irh, frog,
*j
lizards.
. have hinged jaws that can disengage to allow them ro consume
lnakeq
food that is wider than their bodies.
' snakes have forked tongu€s that deposit air molecules on receptors in
the mouth; thus, snakes 'taste" the air, which helps them locaie prey
and sense their way in the dark.
. Snakes are cold-blooded animals that use the energy from the sun to
Wesrern Rattlesnake (Croatus uiridis)
run their bodies' bio-chemical processes, such as liuscle contraction,
AI St. john photo
digestion, growth and reproduition.
The Western Rattlesnake (Croatus uiridis)isOregont only indigenous ' snakes can live offtheir stored far reserve for exrended periods of time.
Tho sub+pecies are recognized in Oregon: th. Norih.rn Shelter and Hibernation Sites
1attl9sryke..
Pacific Rattlesnake (C. u.
!rrg*^),-which occurs irisouthwestern Oregon, . Snakes seek shelter to hide from predators and to regulate body
the mid- to southern villamette valley and the columbia plateau anithe
temperarure. Sites used include rodent burrows, spices underlogs and
Great Basin Ranlesnake (c. a. lutosut),which occurs in south centrar and
ffee sftmps, rock crevices, lumber and rock piles. Man-mad. rt,i,.t*.,
soudreastern oregon. The \(estern Ratdesnake is distinguished from other
are also sometimes used.
Oregon snakes by its broad, triangular head that is mucf, wider rhan its
. Snakes hibernate during winter, either alone or in
neck, vertical pupils (a characteristic shared onlywith night snakes) and a group site called
a hibernaculum.
the ratdes on the end of its tail. overall color parerns di"ser wirh habitat,
. Hibernation sires musr remain warm enough ro prevent death by
rang]ng fr9ry olive to brown to gray. Black and white crossbus may occur
freezing, they must be neither too dry nor loo wet, and they must be
on the tail. \fiestern rattlesnakes averaBe 18 inches to 36 inches ar maturiry,
adequately ventilated.
with some individuals occasionally attaining lengths of four feet, ,nd ,rrrly
five feet. ' snakes will use the same hibernaculum year after year; several hundred
snakes of different species, and sometimes liruds may occupy the same
These snakes are most commonly seen near their den ueas, which are
hibernaculum.
generallyin rock crevices
!*p9r.4 to sunshine. They are most likely to be ' Emergence from hibernation can_ begin as early as Much, depending
seen during the spring and fall when moving to and from hibernaiion
on the species, location and weather. Snakes will stay close to the
sites' Rattlesnakes do not view humans as piey and will not bite unless
hibernaculum in the sprinp basking on neuby rocks during warmer
threatened.
day and reruming.ro its.safe deprhs during coid nighm. Thilpanern
Rattlesnake fangs ue hollow and are used to inject the snake,s venom in wili continue until the day anilnighni*elemperafures stabiiire
order to srun or kill their prey, primarily warm-blooded mammals such in the late spring and the snakes leave for theiisummer
1 m]ce, woodram, ground squirrels and young rabbits and marmors. hunting grounds.
Rattlesnakes are born with muldple sets of fangs that are shed and replaced
Reproduction
approximately every rwo months. In order to .nror. that the snake has at
least one fang with.whiqh to.subdue prey and defend irsel{ the fang on . Courtship and mating occurs shortly after snakes emerge
one side is shed and replaced before the fang on the other side is sh"ed. from hibernation.
Repiacementtake,s qco-uplg of days. Venom is contained in mo giands . Garter snakes, rubber boas and I(estern ratdesnakes beu live young
in the snakes head. Each gland is conneaed to a fang and conuo"lled by from eggs retained in the body until hatching. AII other oregon snlk s
a sphincter that enables the snake to bite without reliasing rny
u.nor, k lry.gg, in protected areas rvhere the egs wil'i receive .nougli.rt.rnrl
can also release measured amounts ofvenom through onJor both fangs.
heat to hatch.
Oregon Department of Fish and Wildlife" Young hatch from July through September and fend for themselves Droppings
after hatching, althou$ there has been documentation ofrattiesnake
Snake droppings ue interesting in tiat you will find a capping of white
mothers defending their young for a period a-fter birth. calcareous deposits at one end. The size ofdre dropping corresponds to
. Young snakes grow rapidly and reach sexual maruriry in two or the size ofthe snake. Snake droppings are cordJike, with constrictions
three years. and undulations.
lit,rtaliy and Longeviry
PRT\E}{T iI{G,LhiD ADDRESSI}iG COI{FLICTS
. Garter snakes have lived as long as 18 yeus in captivigr The lifespan of
Many people fear snakes and consequently try to get rid of them
Oregon snakes in the wild is generally unknown.
unnecesarily. Native snakes are an important put of a healthy ecosystem,
. Snakes are prey for avariety ofwildlife including badgers, coyotes, foxes,
both as predators and prey for other wildlife. 'lhey do not damege
opossitms, raccoons, skunks, weasels, great blue herons, raptors and
property and, with the exception of ranlesnakes, they do not generally pose
other snakes. Some livestock-chickens for example-eat snakes.
any real tireat to humans.
' Habitat loss and alteration are a *reat to snake populations.
Prerent Entrv into tsuiltlings
" Humans kill many snakes each year out of fear and misunderstanding.
" Domestic cats and dogs, Iawn mowers, weed-whackers and vehicles Snakes usually enter buildings at ground level, so sealing all ground-
fatally wound or kill snakes. level holes or cracls can prevent their entry. Seal all cracks and holes in
. Vehicles accounl for more snake deaths than any other cause because foundations and exterior walls, including warped siding, where a small
the snakes are drawn to warm payement to sun themselves. snake could enter. Usell4-inchmesh hardware cloth, caulk, mortar or
a concrete patch to make the seal.A three-inch layer of pea-size gravel
OISSERVTNG S\"qIGS around the foundation will help plug smali holes. Snakes can find easy
Most snake encounters are momentary. Observe snakes from a distance. access to garage areas through open garage doors or under poorly fitting
Never attempt to caprure a snake. Although snakes are often seen as doors. Cover door bonoms with metal flashing or another material. Any
threatening, they hiss, strike or bite only ifyou get too close or ifthey are weather-suipping along the guage and other outside doors should fit
cornered or restrained. They tend to be inconspicuous, prefering to move tightly. These modificadons will also exclude mice and other rodents.
away and hide or lie still in the hope of being overlooked. Most of the Pursuing prey such as small rodents is often the reason snakes attempt to
time, snakes are slow moving, but they can make short dashes to chase enter houses and other buildings.
prey or escape from predators. They are unable to sustain long-&stance Snalies in buildings fall into rwo categodes: those that entered accidentally
movement. Because they are panicululy active and les wary during the and are trying to escape because they find the habitat unsuitable and those
breeding season, be on the lookout for them in spring, Snakes ue often that have entered to find prey or shelter and would take up perman€nt
inactive dudng the hottest part of the day, especially in mid- to late residence if allowed. The former includes small snakes that are trapped and
summer and seek shelter or crawl underground to avoid overheating. In will likely die from la& of food or moisture if not captured and removed.
desert areas, snakes may become active at night when the air cools and Some snakes may hibernate in buildings with leaky cellars or crawlspaces
while the ground remains warm. with dirt floors. The presence of shed skin usuaily indicates that a snake has
Iiaskins Sites been living in the building for some time.
Most snakes reach their prefered body temperature by basking on surfaces Modi& Ilabitat
exposed to sun. They control their body temperature by moving in and To limit the number of snakes living in an atea, reduce their food supply,
out ofthe sunlight and by changing their orientation to it (facing the sun, shelter and encourage natural predators. Areas that provide shelter for
back to rhe sun, etc.). They also derir,,e body heat by lytng on or under rodents and cover for snakes should be eliminated, such as removing
warm surfaces. In hot areas, look fol snakes basking in the morning sun on lumber, woodpiles, bushes, shrubs, piles ofrocks, boards, and other debris
asphalt, concrete, rocks and wooden fences. In cooler regions, they can be lying close to the ground, especially around buildings. Modify areas ihat
seen basking throughout the day, Snakes tend to bask on sun-warmed roads provide cool, damp dark habitat for snakes. Vegetation should be kept
in the evening afactthetoften leads to them being run over by vehicles. shon around the buildings. Mowed lawns and short-cropped fields near the
SheriSnake Sirin house are less attractive to snakes and the rodents they fced on. Of course,
as the number of snakes decreases, the number of rodents and insects may
A growing snake sheds its skin every four to five weeks. When ready
increase, resuldng in different probiems.
to shed, a snake's eyes look bluish white and dull. It may even become
Fences
temporarily blinded undl the old skin splits at the head, and it is able to
crawl out. Shed skin loola like thin, clear plxtic, with every detail of Fences can be used to keep snakes away from buildings and out ofyards.
*ie scales sdll visible, even the eyeball cover. You may find shed skin near A snake-prooffence can be made fiom 30-inch high /+-inch galvanized
boards or lock piles and other piaces where snakes congregate. hardware cloth. The botmm edge should be buried *uee to six inches in
the ground and ttre support stakes should be inside the fence to prevent
irails
snakes from crawl-ing up them. A snake fcnce should be slanted outnard
Snake uaiis are most easily seenin sandy or dusty ueas in their prefered at a 30-degree angle towud the area coniaining snakes. Fences should
habitats. Snakes tracks may be wary or straight iines. Surface material, such also have a self-closing gate design to prel.ent accidental access by snakes.
as sand or loose soil, is usuaily pushed up at the outside of each curve. Regularly inspect the fence to be sure that holes havent been opened under
Oregon Depaftment of Fish and Wildlifeit and that items have not been piled against the outside. Keep grass and ATTMCTING SNAKIS
weeds around the fence mowed.
You have a grearer chance ofauracting snakes to your properry ifit is near
Repellents
an undeveloped site, greenway or freshwater area (e.g., stream). But, yog
Snake rEellents have mixed results. Snakes "smell" via their tongues and can add habitat fearures such as ponds, rockpiles, brush piles and basking
the Jacobson's organ. So, unless a snake just happens to poke its tongue out (sunning) sites to provide suitable snake habitat and improve your chances
at the precise moment that it is moving over the repellent, it will not notice of observing snakes. Habimt-enhancement features ought to be placed
a thing. Even if it does, the smell may not be noxious enough to drive the away from driveways or heavily uaveled roads to minimize road monality.
snake in another direction. See Amract Reoriles and Amohibians to vour Yard (odfl in the Oreson
Extension catalos for more inFormation.
REh,f OVING, TRAPPING AND RILT}CATING SN AKES
Whter
Relocation ofany wildlife, including snakes, for any reason requires a
Many snakes are associated with water. Even baclryard ponds can provide
permit from ODFW: However, you can move a snake outside on the same
habitat for a variery of invertebrates that snakes consume, Build a small,
properfy if it is in a building or if a one-way door can be insralled that will
6sh-free (fish eat allstages of amphibian$ pond for amphibians. Many
allow the snake to exit but ror reenrer.
snakes, garter snakes in particulat feed on tadpoles, adult frogs and
If a snake gets into a house or orher building, it may need help to find its invertebrates found in and around backyud ponds. Place logs, rocla and
way out and get back to its natural habitat. You can hire a Iflildlife Control
planm near your pond to provide shelter for snakes and their prey.
Operator to do the job. For a list of permited Wildlife Control Operators.
call your locai ODF\fl office or refer to the ODF\fl website, Rock Piles
To create a one-way door, seal all the openings except the suspected main Rock piies or rock walls are excellent habitat for snakes. Snakes will use
entrance being used by the snake(s). On that opening, insall a one-way them as cover from predarors and weather, as places to raise young and for
door made from a piece of aluminum window screen rolled into a cylinder basking. You can build rock piles from bricls, rocla or broken concrete.
about 10 inches long and with a siighdy iarger diameter than the enrrance Place your rock pile where it receives both sun and shade each day. A good
hole. Suspend the outlet end ofthe rube offthe ground to prevent the place for a rock pile is nexr to a creek or a pond.
returning snake (s) from finding the entry. The device may be left in place
for a month or longer to allow time for the snakeft) to leave. Make any Brush Files
necessary repairs to the house or orher structure to preyenr the problem Brush piles also provide habitat for garter snakes and attracr insects and
from reoccurring. small mammals that then become prey for snakes. The best places to build
a brush pile are near a hedgerow, shrub, mature uee, pond or recenth
RECCIMMENIIED C0 n- SERIATION ACTIONS cleared area. Iflyou have enough land, make several brush piles and place
from persecudon
Snakes are negatively affeced by habitat alterations and them in spots that get different amounrs of sunlight. Do not place piles in
based on fear and misundersmnding. For example, snakes fare poorly low areas where there is standing water in rainy weather.
when natural lands are broken up by development as it isolates animals
from one another and subjects them to increased risk ofmortaliry as rhey
II{IURED SN,{KES
move across inhospitable terrain. The following conservarion acrions are
recommended to benefit snakes: If you find an injured snake, you can callyour local ODF\X/ office during
n Protect known hibernation sites and other areas used by snakes. weekday business hours for advice or call a certified wildlife rehabilitator.
. Maintain, create and enhance habitat features (e.g., ponds, rock piles, A list of licensed wildlife rehabilitators is availabie on the ODFW web site.
downed wood, brush pile$ to provide suitable habitat for snakes. Do not artempr to care for snai. Ifyou hear but cannot see a rattlesnake, stay calm and locate the
Species Statrs
direction of the rattle. Do not panic and risk being bitten by
Rattlesnake
Iflestern Sensitive - Cdtical (Villamette Valley)
accidentally moving closer or stepping on the snake. Once you know
Common Kingsnake Sensitive - Vulnerable hange-wide), Proteced
the direction of the snake, move away in the opposite direction.
Califomia Mounmin Kingsnake Sensitive - Vulnerable hange-wide), Proteaed . Ratdesnakes are occasionally found near buildings seeking shelter,
Snake
Sham-tailed Proteaed shade, or prey but they seldom enter houses.
Vestern Ground Snake Proteaed
Prevent Problems While Hiking
. Stick to well-used, operr trails. In brushy ueas, use a walking stick to
NONNATI!'E, INVASNT AND EXOTIC SNAKES alert a snake ofyour approach.
. Avoid walking through thick brush and willow thickets.
Exotic pets . Do not step or put your hands where you cannot see.
Some nonnative snake species are legal to have as pets in Oregon, while . 
