Spiders and Trapdoor Spiders Wednesday January 4, 2012
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Our own San Diego trail guide, Donna Walker, inspired by her new career at Hearts Pest Management, took to the Mission Trail this past week and came back thrilled by her find of a trapdoor spider.

Article by Donna Walker

Hearts Pest Management Customer Service and MTRP Trail Guide

Spiders, Trap Doors, Jumping Acrobats, Oh My!

General Spider Information

Spiders can be identified by their 8 legs (jointed) and 2 body parts.  They do not have wings or antennae.  Since they spend most of their lives capturing and eating other insects, they are a natural form of pest management, however, they too can become pests once they decide to make webs inside your home.  Most spiders are not dangerous to humans but many of us fear them because of the way they look.  Spiders will bite out of their own fear and try to defend themselves when disturbed.

Venomous Spiders

In California, the only spider to really be careful of is the venomous black widow.  The black widow usually lives in dark places like woodpiles, attics, and garages.  In size, it is a half to one inch in length; its body is shiny with a large abdomen and a red/orange marking in the shape of an hourglass on the underside of its belly.  Spraying with pesticides is more effective when the actual spider and/or egg sac is sprayed.

A black widow spider hanging out in a corner

A black widow spider hanging out in a corner

Another venomous spider commonly feared but is often misidentified is the brown recluse.  It is not native to California.  If the brown recluse has been found in California, it was most likely brought here from its native habitat, the south-central portion of the Midwest.  Like the black widow, the recluse likes to hide in dark spaces or corners.  It is about a half-inch long, and light brown in color.  It has 6 eyes rather than 8 like other spiders.  You can read more about venomous spiders and treatment for bites at California Poison Control

Brown Recluse Spider Resting in Wait for Prey

Brown Recluse Spider Resting in Wait for Prey

Scary But Fun Spiders

Jumping spiders are the largest family of spiders with more than 300 species in the United States.  Hunters by day they make no web but instead they stalk and pounce on their prey by jumping long distances.  Jumping spiders diets include earwigs, flies and such other pests.  They are easily identifiable by their large, middle eyes, giving them the keenest vision of all spiders and the ability to respond to any movement up to 18 inches away.  As true acrobats, jumping spiders attach a safety strand of silk just prior to leaping from one area to another.

A Jumping Spider in Plain View

A Jumping Spider in Plain View

Trapdoor spiders

A trapdoor spider in plain view

A trapdoor spider in plain view

Trapdoor spiders are curious looking creatures ranging from Virginia, South to Florida and West to California.   The California Trapdoor Spider lives in chaparral coastal sage scrub and mid-level forest habitats.  It burrows into the hillside and low embankments along trails making a perfect hole complete with a trapdoor hinged with silk for sneaking out and catching unsuspecting prey.  It resembles a small tarantula with shiny, rather than hairy legs. This spider is non-aggressive but may rear up and show its fangs if harassed.

A trapdoor spider peeking out of a hole

A trapdoor spider peeking out of a hole

A trapdoor spider close up

A trapdoor spider close up

A close relative to the tarantula, trapdoor spiders are smaller and have shiny rather than hairy legs.  Their chelicerae (jaws) are strong like rakes which helps loosen the earth when digging to create their homes.  The burrow is then lined with silk and looks like a hollow tube.  The female lays eggs in the fall at the bottom and covers them with a sac attached to the tunnel wall.  Once the spiderlings are hatched, she cares for and feeds them all through the winter.

Illustration of a Trapdoor Spider by Donna Walker

Drawing of a Trapdoor Spider Catching a Cricket

When a potential meal comes close such as cricket or even a small lizard, the spider uses its strong chelicerae to hold the trap door shut, waits until it can feel the vibration of the passing prey, then quickly throws the lid open, grabs the unsuspecting prey and returns with it down the tube.

The California Trapdoor Spider lives in native chaparral and mid-level forest habitats, however, its tunnels can also be found in natural areas of soil, free from plants, like hillside slopes. These spiders would not be considered pests but a species to protect.  Below is a picture of a California Trapdoor Spider taken on the Oak Grove Loop at Mission Trails Regional Park.

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