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SPIDERS |
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PHYSICAL CHARACTERISTICS
Spiders are predators paralyzing or killing their prey
with venom. They typically feed by injecting a predigestive fluid into the body
of their prey and then suck out the digested food.
Spiders can survive for long periods of time without food and also have been
known to survive even whole house fumigation.
There are anywhere from 500 to 800 species of spiders in the United States.
Spiders have only 2 body regions, no antennae, no compound eyes and have 4 pairs
of legs. The female lays her eggs either in a dark place or in egg sacs
depending on the species. Both the black widow and the brown recluse have egg
sacs. The young are called "spiderlings".
All spiders have poison glands containing venom. They use their venom to kill
their prey and feed on the body fluid of their catch.
Most spiders can climb and hang by silk webs, and some can even jump.
Many spiders, especially young spiders, move long distances by spinning a web
and letting the wind carry them and their web. This is called ballooning. The
spider climbs to the top of a roof or fence post and releases a strand of silk
into an air current. Some spiders are known to have been carried in this manner
for distances of 60 miles and upwards to 5,000 feet.
Some spiders do not spin webs.
Males are usually smaller than females of the same species.
The most common spider found in the eaves of homes in California is the cellar
spider.
BLACK WIDOW
There are two kinds of spiders that bite and can cause
painful poisoning in humans, they are the black widow spider and the brown
recluse spider.
Female black widows are black with a red or orange hour glass shape on the
underside of the abdomen.
Black widows are present in every state in the United States as well as other
countries with similar or warmer climates.
A female may produce four to nine egg sacs during a summer. Egg sacs contain 300
to 400 eggs which will hatch in about 8 to 10 days. Egg sacs appear white in
color, but after a while turn pale brown.
After laying eggs the female is hungry and more likely to bite a human.
In some instances bites can be fatal.
A bite may cause pain at the site of the bite, general aching of the body,
headache and nausea but in most cases symptoms disappear in 2 to 3 days.
The black widow web is an irregular, tangled, criss cross web woven of a coarse
silk. Strand for strand it is stronger than steel, and is used for cross hairs
in large telescopes in observatories.
BROWN RECLUSE
Brown recluse spiders can be identified by the violin
shape on the back of the thorax. Also they have six eyes while the majority of
spiders have eight.
"Fiddleback spider" and "Violin spider" are other names of the brown recluse
spider.
Some spiders may have a bite as toxic as that of a brown recluse, but because of
the difficulty in obtaining venom, research on identifying these spiders is
nearly impossible.
People are most commonly bitten in bed, dressing or cleaning storage areas.
Adult male and female brown recluse and immature spiderlings are capable of
injecting venom which may result in serious lesion formation. If damage is
severe, a skin graft is sometimes required.
TREATMENT
Part of the treatment is not only providing a residual
barrier for the control of insects and spiders, but to physically
sweep down all accessible spider webs. This helps control in 3 ways:
- It removes the harborage of the spider.
- It forces the new spider to contact the residual
barrier in order to get to the home.
- The technician will kill any visible spiders in the
process of removing the actual web.
SPIDER MYTH: It has been widely reported that a
black widow female eats her mate. Generally, these observations have been made
under laboratory conditions which are not natural and may not represent what is
normal. Actually males live longer when with a mate because he lives off of the
food captured in the females web.
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