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As The Mercury Rises So Does Pest Pressure


As California’s warm spring rolls toward summer the Clark Man wants to remind you that as the temperature rises on the thermometer so does pest activity.

And as you get out and about with your spring and summer activities, we remind you to keep any eye out for a pair of pests that can potentially cause harm to you and your family – spiders and stinging insects.

Spiders such as the common house, cellar, sac, gray house, brown widow and black widow are commonly found throughout various parts of California. And while spiders are beneficial to our eco-system since they trap and eat other invasive insects, they do tend to make most homeowners a little uneasy.

While most spiders are harmless, the black widow, with its rather creepy name, and venomous bite can post a threat for those coming into contact with it. For the record, the black widow spider gets it morbid name from the fact that the female often eats its male counterpart after mating.

Homeowners should not mistake the black widow spider’s withdrawn nature as a sign of friendliness. Black widows prefer dry, dark undisturbed places to spin their webs and hunt their prey.

Some areas where the black widow is commonly found include:


  • Storage sheds

  • Garages and carports

  • Under decks and benches

  • Wood or yard debris piles

  • Rocks and landscape bricks and pavers

  • Inside storage boxes, rolled up sleeping bags and yard furniture


When a black widow’s nesting site is disturbed they can bite unsuspecting humans. Usually these bites are no worse than a wasp sting but in some cases they can cause an anaphylactic reaction that requires medical treatment.


The Clark Man recommends wearing a pair of heavy gloves when cleaning out the garage or shed, unpacking items that have been stored away or working in the yard to avoid the black widow’s bite.

While yellow jackets and wasps are typically considered a late summer pest they do forage in the spring in search of a place to construct their nests. They will build their nests below ground or in undisturbed areas such as the eaves of a house or in trees.


The Clark Man recommends keeping food covered at outdoor events and cleaning up spills of sugary liquids and foods so as not to attract stinging insects.

And if you see what appears to be a nest, do not attempt to take the job of removing it upon yourself. Yellowjackets and wasps will aggressively defend their nests and with upwards of 30,000 inhabitants, the odds are not in your favor – call a pest professional to remove it.

Remember, if you have question on spiders or stinging insects, call 800/WE-NEED-YOU or drop me an e-mail at clarkcares@clarkpest.com


Until next time, I’m the Clark Man and thanks for helping me keep unwanted pests out of your home.

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The Wolf Spider - Clark Pest Control


Written by Fred Speer
Clark Pest Control 

wolf spider

Spiders often trigger fear in people who come into contact with them.  Frequently, they are portrayed in movies and TV shows as menacing, eight-legged, blood-thirsty freaks on the prowl for their next victim.

While sometimes this is a misconception, there is one spider that fits this description. The wolf spider is the perfect eight-legged hunter, one that will either lie in wait or stalk its prey. This agile, lightning-fast spider poses little threat to humans, and will only bite when provoked.

The wolf spider is often mistaken for a very young tarantula, because of its size, color, and “stout” stature. Its body size ranges from one to 30 millimeters. Interestingly, some wolf spiders have the ability to walk on water to avoid becoming prey.

A Softer Side of the Wolf Spider

One thing that really sets this spider apart from other spiders is the way the mother interacts with her offspring. Newly hatched spiderlings will climb onto her back, and they will stay there for up to a week before they venture off on their own.

Friend or Foe

The wolf spider should be considered our friend, as they are beneficial pests that munch on crickets, cockroaches, and various flying insects.  When a wolf spider bites a human, usually the damage is minimal, and typically there is no need for treatment unless the person bitten is allergic, or is having a reaction.

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World’s heaviest spider title challenged at Museum


Source: Natural History Museum

goliath birdeater

Boxing gloves were nowhere in sight for a world spider heavy-weight title challenge at the Natural History Museum last month.

The contenders were the Hercules baboon spider, and the current Guinness World Records (GWR) holder for world’s heaviest spider, the Goliath bird-eater.

Museum bug expert George Beccaloni was contacted by GWR Editor-in-Chief Craig Glenday after reports of a possible rival. Craig asked George if he could check the size of the Hercules baboon spider as the Natural History Museum has the world’s only known specimen and George is the author of the Museum book, Big Bugs Life-Size.

Craig was there to adjudicate when George measured the two spiders. Using a jar of alcohol and the Archimedes' Principle, both specimens were submerged to discover the volume of alcohol they displaced, and therefore the volume of their bodies.

Spider specimens are stored in alcohol and this makes their internal organs shrink. The water inside them gets replaced by alcohol, which is about 25% lighter than water. This means that their weight when they were alive would be about 25% greater

Knowing that they would weigh about 1g per cubic cm when alive means that their weights can easily be calculated  if their body volumes are known.

Winning measurements

The female Goliath bird-eating spider specimen measured 69 cubic cm, more than double the volume and therefore the weight of the Hercules baboon spider that measured 22 cubic cm.

So the Goliath bird-eating spider remains the world's heaviest spider species, with the heaviest recorded individual being a 12-year-old captive female called Rosi - according to GWR, it had a body length of 119.4mm and weighed a massive 175g

'Rosi was considerably heavier than the Museum specimen that we measured,' says George. 'It's amazing to think that she weighed about as much as 5.8 house sparrows!' 

Click here to read the entire article

To learn about household spiders you may encounter in California visit our Pest Library today.


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Swimming Spiders - Diving spiders make their own gills


In Germany’s Eider River, spiders not only swim with the fishes, they kind of breathe like them, too.

Eurasian diving bell spiders (Argyroneta aquatica) survive entirely underwater by living in large air bubbles, which the crawlers trap indiving spider silken webs. A new study shows that these bubbles work like a “physical gill,” drawing oxygen in from the water to match much of the spider’s consumption. Researchers from Australia and Germany report their findings in the July Journal of Experimental Biology.

For insects, physical gills are nothing new. Certain small bugs bob and dive into streams and rivers with the help of plastrons, trapped films of air that coat their bodies. As the bugs consume this trapped oxygen, gas diffuses in from the surrounding water, replenishing the supply, says Morris Flynn, a mechanical engineer at the University of Alberta in Canada. In contrast, diving bell spiders seem to actively replenish their air bubble – called a diving bell after the antique submarines – by frequently traveling to the surface to grab more oxygen. They trap the air between their back legs and abdomens, later adding it to the bell. This keeps the diving bell from collapsing.

Click here to learn more about the diving spiders!

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Common Spiders in California | Clark Pest Control


Fred Speer
Clark Pest Control

Spiders are considered to be air-breathing arthropods with eight legs, chelicerae and fangs that can and will inject venom if threatened or disturbed. Spiders have been identified as the largest order of arachnids, ranking seventh in total species diversity among all other groups of organisms. We most frequently encounter in our homes, yards and out structures are the Wolf spider, Cellar spider, Black widow, Yellow sac spider and even occasional, although extremely rare in California, the Brown recluse.

The Wolf spider

The name Lycosidae, comes from the Ancient Greece meaning “wolf” as the Lycosidae or Wolf spider has very good eyesight and is an outstanding agile hunter.

The Wolf spider preys on insects that are crawling or resting on the ground. Wolf spiders actively hunt in the open during the day and night, often observed on the ground in litter and on low vegetation. The Wolf spider burrow is often found under debris or on soil. Instead of spinning webs to catch prey, make a small, thick web where they rest. Wolf spiders a distinctive pattern of eyes: four small eyes in front in a straight row, one middle pair of larger eyes, and one rear pair of widely spaced eyes on top of the head.

Adult Wolf spiders have been mistaken for young to juvenile Tarantulas as they have long hairy legs. They are usually black and white or strongly contrasting light and dark, which can make them difficult to discern unless they are moving. Currently, there is about 200 species in North America.

The Cellar spider

Cellar spiders have extremely long, skinny legs with small bodies that are usually tan or gray. The web of a cellar spider is usually very messy, similar to the web of a cobweb spider. Like all spiders, cellar spiders have 8 legs, 2 body parts, and fang-like mouthparts. The body length of adult cellar spiders about 1/4" or less.

The Black widow

The black widow spider, Latrodectus hesperus, is the most common harmful spider in California. Venom from its bite can cause reactions ranging from mild to painful and serious, but death is very unlikely and many symptoms can be alleviated if medical treatment is obtained. Anyone bitten by this spider should remain calm and promptly seek medical advice; it is helpful if the offending spider can be caught and saved for identification.

The typical adult female black widow has a shiny black body, slender black legs, and a red or orange mark in the shape of an hourglass on the underside of the large, round abdomen. The body, excluding legs, is 5/16 to 5/8 inch long. Only the larger immature female and adult female spiders are able to bite through a person’s skin and inject enough venom to cause a painful reaction.

The Yellow sac spider

The common, house-dwelling agrarian sac or yellow sac spider, Cheiracanthium inclusum, is a small spider that spins a silken sac web in the corners of ceilings and walls, and behind shelves and pictures; it is also commonly found outdoors in shrubbery. This spider is light yellow and has a slightly darker stripe on the upper middle of the abdomen. The eight eyes of this spider are all about equal in size and arranged in two horizontal rows.

Yellow sac spiders can be seen running on walls and ceilings at night and quickly drop to the floor to escape if they are disturbed. Bites usually occur when the spider becomes trapped against a person’s skin in clothing or bedding. It is estimated that sac spiders are responsible for more bites on people than any other spider. Typical symptoms of a bite include initial pain, redness, and sometimes swelling.

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The yellow sac spider hits the road with the Mazda 6


Mazda 6 recall: Beware the yellow sac spider and the web it weaves

By Melissa Bell

The Washington Post Blog

In Friday's terrifying news story of the day, a tiny spider's web might crack apart your car engine and start a fire. But only if you have a Mazda 6. And no one has any idea why this is happening.

The news has forced Mazda to recall 65,000 cars in the United States, Canada and Mexico. The spider is the yellow sac spider.Yellow Sac Spider Mazda dealers reported 20 cases of webs being found in a vent connected to the fuel tank system. The webs could clog the ventilation system, applying pressure to the fuel tank, which could then crack and cause a fuel leakage. The Associated Press reports:

"Mazda spokesman Jeremy Barnes said dealers had identified 20 cases in which spider webs were found in the vents. The webs were linked to yellow sac spiders, Barnes said, but it was unclear why they were crawling into the Mazda 6 rather than other vehicles.Adding to the mystery, Barnes said the arachnoid attraction to the sporty cars -- which the company has marketed with its 'zoom-zoom' tagline -- had no specific connection to a particular region of North America."

Click here to read the entire article at The Washington Post's Blog


About the Yellow Sac Spider

The Cheiracanthium, also known as the yellow sac spider is a genus of spiders in the Miturgidae family. Certain species are commonly known as the "yellow sac spider". They are usually pale to in colour, and have an abdomen that can range from yellow to beige. 

The yellow sac spider's venom is necrotic (premature death of cells and living tissue and can cause a small lesion in humans. Because of the necrotic nature of the wound, MRSA (a bacterium responsible for several difficult-to-treat infections in humans) infection is a danger and victims are advised to seek medical treatment. 

For more information on Spiders Clark Pest Control treats, visit our spider page.



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Man living in shop window with 400 deadly spiders


Source: CNN
Origional Story

Forget bedbugs in New York, imagine dealing with deadly spiders - 400 of them everywhere.
Now, picture waking up each day surrounded by them for three weeks while living in the confines of a storefront window.

living with spiders

It may sound like something only a crazy person would do - but it's actually all a part of Nick Le Souef's plan to help a charity.
The Melbourne man, who by the way told reporters he doesn't "like spiders all that much," is being dubbed Australia's very own Spiderman for his attempt to break a record he set 30 years ago - and raise $50,000 for a children's charity.
"I'm not afraid of them, but it's just that I'm not overly keen on them," the 67-year-old told the Australian Broadcasting Company.
Le Souef originally planned to do the stunt with snakes but was not allowed.
According to Australian media reports, the number of creatures has dwindled a bit after some began to turn on each other - a sign things may get more difficult for him, some say.
Le Souef says the incident doesn't worry him and he isn't afraid of being surrounded by the dangerous blackhouse, redback and huntsmen spiders.
"Redbacks are very calm," he said. " Once they make their webs and their sort of little nests, they don't move around," he said.

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Baby cannibal spider gang makes web vibrate in time

BY Matt Walker
Editor, Earth News

Good vibrations (courtesy of Dr K W Kim)

It is like something out of a horror movie: baby spiders devour their own mother, then climb aboard her web, and make it throb in a series of pulsating vibrations.

But that is exactly what black-lace weaver spiderlings do, a biologist in South Korea has discovered.

After cannibalizing their mother, up to 160 spiderlings gather and contract their bodies in synchrony, collectively pulling at the web to make it vibrate.

Ultimate sacrifice

Most spiders are solitary animals.

But some are social animals, living in communal webs throughout their lives, cooperating in nest construction, brood caring and prey hunting.

Other species are subsocial, where individual spiders come together and cooperate at certain stages of their lives.

They belong to the subsocial spiders, with the young baby spiders displaying a range of intriguing behaviours.

For example, female A. ferox spiders produce a single clutch of 60-130 spiderlings, which she feeds by laying eggs for her offspring to eat.

But then she makes the ultimate sacrifice: she encourages her spiderlings onto her body, and allows them to devour her alive (see video below).

After she has died, the spiderlings then form a social group for 3-4 weeks until they disperse from the social nest.

During this time, the spiderlings are known to cooperate by going hunting together.

By cooperating on a hunt, the spiderlings are capable of attacking and subduing prey up to 20 times bigger than themselves.

Web shake

But Dr Kil Won Kim of the University of Incheon of the Republic of Korea, who has researched this cooperative hunting behaviour, has discovered that the spiderlings gang together in another bizarre, and previously unknown way.

"After matriphagy [the eating of the mother], A. ferox spiderlings show synchronous movement, contracting their bodies simultaneously," Dr Kim told the BBC.

This behaviour emerged the day after the death of the mother, and was triggered by intruding insects, mites or worms approaching the web.

Eating mother alive (courtesy of Dr K W Kim)

An individual spiderling contracted its body, pulling at the web as it did so.

Almost immediately, other spiderlings joined in, also contracting their bodies.

That created a bigger effect, which was to make the whole web throb in a series of rhythmic vibrations.

At its peak, up to 60 per cent of the spiderlings engaged in this behaviour at any one time.

The denser the group of spiderlings, the stronger the vibrations of the web, and the presence of other spiderlings nearby encouraged others to also contract their bodies.

The spiderlings also performed contractions at the highest frequency four days after eating their mother, with the behaviour declining as they aged.

It also occured during the period before the baby spiderlings were old enough to go hunting.

Scary tactic

It is unclear why the baby spiders make their web throb in this way.

"Contractions may function as antipredatory behaviour," says Dr Kim.

A few lines of evidence point to this.

The baby spiders do not do it in the presence of the mother, which likely protects them before sacrificing herself.

They also vibrate only when a large intruder is nearby, suggesting it is a defence mechanism, as the vibrations would be transmitted to any intruder touching the web.

The visible movements of the web may also give an intruder the impression that there is a much larger organism nearby, again deterring them from approaching the vulnerable baby spiders.

Few other collective defence responses have been recorded in spiders.

One other example is in the territorial social spider Cyrtophora moluccencis. When a bee or wasp flies over a female's cocoon, she will shake it vigorously, an action that prompts other females nearby to also shake their cocoons, perhaps to deter the invader.

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Deadly spiders found in county


Source: Lancashire Evening Post

black spider

RED ALERT: Poisonous spiders like these redbacks have been found in Lancashire

Published on Fri Jun 25 09:48:24 BST 2010

Extermination experts are standing guard at a Lancashire aerodrome after deadly Australian spiders were discovered. Up to five redback spiders and eggs were found by workers in transportation crates at BAE Systems, Warton. Rentokil Pest Control was called in and its staff will remain on site until the all-clear is given. Shocked BAE workers raised the alarm and the area was sealed to prevent the creatures scuttling away. Chiefs at the site, where Eurofighter jets are built, do not believe any of the spiders have left the immediate area. A spokesman for BAE said: “I can confirm that we have found a small number of redback spiders that were discovered in transportation crates that were returned from Australia. “We contacted the appropriate authorities and have engaged a firm of pest control experts. “They have been carrying out inspections and treatment.” The workers immediately recognised the potentially deadly creatures thanks to training given to them prior to work trips to Australia to carry out testing. The spokesman said: “We called Rentokil and they inspected the areas where they had been found and laid down insect detection. “They cordoned off the particular areas so they couldn’t move.” The BAE spokesman rubbished claims that several of the spiders fled to nearby fields, sparking fears they could invade the UK, as they tend to prefer to stay in one place, close to their web and eggs. He said: “That’s not in their nature. “We have no evidence of them moving anywhere apart from where they were found. “Rentokil is carrying out regular inspections.” He said that no-one had been bitten by the spiders, but they had been in touch with the Department for Environment, Food and Rural Affairs (Defra), the Food and Environment Research Agency (Fera), the Health Protection Agency (HPA) and the local authority for advice. An investigation has now been launched into how the spiders ended up in Lancashire on Friday, from 10,000 miles away. The spokesman added: “The transportation crates are fumigated before they are packed and they are then loaded into container crates. “We believe they have got inside the container crates and attached themselves to the outside.” Thousands of people are bitten by redbacks in Australia each year and 15 people have been killed. They are considered to be one of the country’s most dangerous spiders.

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Desperate Female Spiders Fight By Different Rules


If you thought women's pro wrestling was a cutthroat business, jumping spiders may have them beat.

In most animals the bigger, better fighter usually wins. But a newjumping spider study of the jumping spider Phidippus clarus suggests that size and skill aren't everything - what matters for Phidippus females is how badly they want to win.

Found in fields throughout North America, nickel-sized Phidippus clarus is a feisty spider prone to picking fights. In battles between males, the bigger, heavier spider usually wins. Males perform an elaborate dance before doing battle to size up the competition. "They push each other back and forth like sumo wrestlers," said lead author Damian Elias of the University of California at Berkeley.

This fancy footwork allows males to gauge how closely matched they are before escalating into a full-blown fight. "Males rarely get to the point where they solve things by fighting," said co-author Carlos Botero of the National Evolutionary Synthesis Center in Durham, NC. "Before the actual fight there's a lot of displaying. This allows them to resolve things without injuring themselves."

But when the researchers watched female fights, they found that females fight by different rules. They skip the preliminaries and go straight for the kill. "Males have a more gentlemanly form of combat, whereas in females it's an all-out fight," said Elias. "At the drop of a hat they start bashing and biting each other."

And unlike male combat, female feuds were often fatal. "They don't give up, even when their opponent is beating them to a pulp," said Botero. "They keep going until one of them is dead, or severely injured."

The researchers were unable to predict which female would win based on size or strength. "Nothing we could measure predicted which one would come out on top. That was really unexpected," said Elias.

At first, the researchers wondered if victory went not to the bigger fighter, but to the owner of the battlefield. "In a lot of animals one of the things that determines whether they win a fight is whether they're on their own territory," Elias said.

Phidippus clarus spiders live in nests they build from silk and rolled up leaves. While males are nomads, wandering from nest to nest in search of mates, females generally stick to one nest and guard it against intruders.

Click here to read the entire article

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