The brown recluse spider is most common in the south-central United States, including Tennessee.  These spiders are also commonly referred to as “fiddleback” because of the violin-shaped marking on the top surface of the head/back.  They are often found in dark, unventilated areas, which are rarely disturbed by humans. 

SIZE
Body - (1/4 to 1inch) The legs span an area roughly the size of a quarter to a half-dollar.

COLOR
Light yellowish/brown to a dark, reddish or chocolate brown, but most are light to medium brown.

DESCRIPTION

• The Brown Recluse spiders have these four characteristics:
• Six eyes in pairs
• Dark pattern near the eyes (“violin” shape)
• Uniformly colored abdomen with fine hairs
• No spines on the legs

HABITAT
Brown recluse spiders prefer isolated corners and sheltered areas with low moisture levels.  These spiders are called “Recluse” for a reason – they prefer areas unoccupied and not disturbed by humans.  In a study conducted by Jamél Sandidge, Entomologist, the top 10 areas where brown recluse spiders are found in homes:

• Near furnace and water heater
• Second floor bedrooms – unoccupied
• Any room without air conditioning or ventilation
• Bathroom – behind toilet or tub
• Near plants
• Basement – under stairs
• Basement – in piles of wood, boxes, carpet or clothing
• Windowsills
• Behind entertainment center
• Bedrooms

LIFE CYCLE
The brown recluse spider has been known to live up to two years in captivity. According to the University of Tennessee:

• Brown recluse spiders may live five to 10 years under ideal conditions.
• These spiders develop egg sacs between February and September, with most development from May through July.
• Each egg sac normally contains between 20 and 50 eggs.
• The female usually constructs up to five egg sacs.
• Spiderlings emerge from the egg sac within three to five weeks and stay in the web with the mother for one or two molts (shedding of skins) before migrating to other suitable habitats.
• The spiderlings molt six or seven times before becoming an adult in the following year.
  

CONTROL
Control of indoor infestations of the brown recluse spider can take a long time (6 months or more) and can be difficult since they tends to be widely dispersed within infested buildings, and the spiders seeks isolated sites. The first step in effective management of brown recluse spiders is to conduct a thorough inspection of the property. Control of spiders, including the brown recluse, is best achieved by following an integrated pest management (IPM) approach. IPM involves using multiple approaches such as preventive measures, exclusion, sanitation, trapping, and chemical treatment when necessary.

Large infestations will take multiple treatments targeting the spider itself, common habitats and its food sources – other insects.

• The bite may feel like a pinprick and/or stinging sensation followed by intense pain
• The initial bite area may have a little red mark.
• The lesion from a brown recluse spider bite may grow 1½ inches by 2¾ inches or smaller.  The lesion may exhibit blue-gray or blue-white colors and surrounded by redness—hence the “red, white, and blue sign.”
• A small white blister usually initially rises at the bite site surrounded by a swollen area. The affected area enlarges and becomes red, and the tissue is hard to the touch for some time.
• After a few days, the bite site can erupt into a “volcano lesion,” basically a hole in the flesh due to damaged, gangrenous tissue.
• Sometimes a person may not be aware of the bite for 2 to 8 hours.
• Some victims experience general systemic reactions that may include restlessness, generalized itching, fever, chills, nausea, vomiting, or shock.

Preventing Spider Bites

• Inspect bedding and towels before use.
• Shake out clothing and shoes before getting dressed.
• Wear gloves when handling firewood, lumber, and rocks.
• Move the bed away from the wall. Remove bed skirts.
• Don’t store boxes underneath beds.
• Exercise care when handling cardboard boxes (some spiders may inhabit the space under folded cardboard flaps).

First Aid
If bitten, remain calm, and immediately seek medical attention by contacting your physician, hospital and/or poison control center.

1. Apply an ice pack directly to the bite area to relieve swelling and pain.
2. Collect the spider (even a mangled specimen has diagnostic value), if possible, for positive identification by a spider expert.
3. A plastic bag or small jar is useful and with no preservative. However, rubbing alcohol helps to preserve the spider.

Interesting Facts
Webs:
The brown recluse spider builds irregular, patternless webs in poorly-lighted areas. There is usually a thicker portion of web (sometimes almost tubular) built in a protected area such as in a crevice or between two rocks. The spider will retreat to this area of the web when threatened. Silk webs are laid down as the spider walks, and the web becomes thicker. Webs can eventually become sheet-like if located in an area of abundant prey.

Feeding:
Brown recluse spiders feed on a variety of insects and other  a spider. Their bite quickly paralyzes prey, which may remain alive for a few days until the spider decides to feed on it. The spider is alerted to the presence of prey by web vibrations caused by passing prey. However, there is some evidence that the brown recluse spider might forage short distances from the web at night. Prey is located and bitten, but not wrapped in silk.

Click Here > Brown Recluse Service Guidelines

For more information on spider control problems, visit Spider Pest Control . Com or Knols: Brown Recluse Spiders - Pest Control Measures