Black Widow

Black widows are named for the female’s occasional cannibalistic practice towards her mate. Females are easier to identify, and sometimes males aren’t even recognized as black widows. Males are smaller, and lighter in color. However, females are the only sex able to inflict the painful bite. Females are dark colored, around ½” long, with a bulbous abdomen. Luckily they have a red hourglass on their underside, which is made visible by the female’s habit of hanging upside down from her web. Black widow populations are erratic, sometimes rising and falling dramatically over the years. They prefer to make their webs in dark, dry, undisturbed places. They are common underneath houses, in garages, or outside in woodpiles. Black widow webs are very irregular in design, not looking like the traditional bulls eye shape. Females can get defensive around their webs and bite, especially when there are egg sacs present. The venomous bite from one of these spiders causes pain rather quickly. If a black widow bite is suspected, look for the two small teeth marks on the swollen area. Although 99% of people survive the bites, it is still a good idea to contact your doctor – especially if a young child, or older person is involved. Watch out for signs like nausea, tremors, and sweating if bitten. First aid such as washing the area and applying ice can provide minor relief. To keep from getting bitten wear gloves when working in areas that could have spiders, and pay attention. Look for irregular webs, egg sacs, and spiders. Removing webs, and crushing spiders and egg sacs is helpful in controlling overall black widow populations. Fogging for black widow spiders is particularly effective for knockdown, because they spend most of their time on their web. Residual sprays have to contact them directly, since they may not crawl through them.


Hydrex Pest Control of the North Bay Inc.
4685 Scotts Valley Rd.
Lakeport, CA 95453
(800) 760-3028

Hydrex Pest Control of the North Bay Inc.
1120 Industrial Ave
#18 Petaluma, CA 94952
(707) 795-6345


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