Black House Spiders

Facts, Identification & Control

Scientific Name:

Badumna insignis

Appearance

What do they look like?

B. insignis is a dark-colored spider with the mature female about ¾ inch long with a 1 ¼ inch leg span.

The males are smaller as their body is about 3/8 inch long.

Both the males and females have dark brown legs and a gray abdomen with light markings on the top.

How Did I Get Black House Spiders?

As their name implies, black house spiders sometimes live indoors. Like most home-invading species, the pests come inside seeking shelter or food. A black house spider often resides in the bathroom or basement, and the presence of cobwebs may hint at the location of an infestation.

How Serious Are Black House Spiders?

Unlike black widows, black house spiders do not have a potentially fatal or medically serious bite. However, they still prove to be a nuisance and leave messy webs with funnel-shaped entrances. Although they only bite as a last resort, black house spiders can become aggressive if people touch them. Bites may be painful and cause skin irritation or other symptoms.

How Do I Get Rid of Them

What Orkin Does

The Orkin Man™ is trained to help manage house spiders. Since every building or home is unique, your Orkin technician will design a special program for your situation.

Keeping spiders out of homes and buildings is an ongoing process, not a one-time treatment. Orkin’s exclusive A.I.M. solution is a continuing cycle of three critical steps — Assess, Implement and Monitor.

The Orkin Man™ can provide the right solution to keep spiders in their place...out of your home, or business.


Habitat, Diet, Life Cycle

Their normal outdoor habitat is logs, tree trunks, rock walls and building crevices and gaps. Black house spiders prefer outdoor habitats, but they will go inside buildings and may be found where their prey is located including corners, around windows and doorways. It is common for this spider to be located near a light source since lights attracts a wide variety of prey insects like flies, beetles, ants, moths and mosquitoes. The spiders may themselves become prey for a number of other spiders, wasps and parasitic flies. Adult spiders live for about two years.

Reproduction

The female constructs several white silk egg sacs, which are secured within the web. The female stays with the eggs until they hatch. Once hatched, the immature spiderlings then disperse by producing a thread, which is blown about by the wind, so the young can move to other locations.

Signs Of An Infestation

The presence of the spider and their webs indicates black house spider activity.

Distribution

Black house spiders are widely distributed throughout Australia and New Zealand.

More Information

Do They Bite?

Black house spiders are not aggressive and bites are infrequent. However, when bitten, the bite may cause pain and localized swelling. Occasionally other symptoms like nausea, vomiting, sweating and skin lesions are produced.

Sealing all cracks, gaps and crevices that provide access inside the home is an important way to prevent spiders from wandering into the structure. Using a vacuum or broom to remove spiders, webs and egg cases is another way to prevent the spiders from moving inside. Still another method is making sure the black house spider’s food source is kept to a minimum and harborage sites are removed and cleaned up.

Should the homeowner need help controlling these or any other spiders, contact your pest management professional and request an inspection. Your pest management professional can then use his or her inspection findings to prepare a comprehensive pest management plan that will effectively and efficiently deal with the specific pest problem.