Creepy crawlers…creeping in by Jamee Larson

Arachnophobia, or fear of spiders and other arachnids, is one of society’s most common phobias. It has been the subject of extensive research and even immortalized in the 1990 movie Arachnophobia. Experts estimate that almost fifty percent of women and ten percent of men are afflicted with this phobia. That is not to say, however, that those without this debilitating fear are comfortable in the presence of eight-legged critters.

Why has there been a

population growth in the F/M area?

The Fargo/Moorhead area has seen an increase in the number of spiders this summer. This can be attributed to a number of factors, one of which is the weather. Mild winters can actually increase population levels as many that would normally freeze do not. Dr. Janet Knodel, Extension Entomologist and Associate Professor at NDSU, explains the affect that the weather can have. “Two weather conditions that can impact insect development are temperature and moisture. Insect development generally speeds up with warmer temperatures, since insects are poikilothermic (cold-blooded).” In addition, she attributes the larger population to the area’s dry summer. “The drought favors some insects, such as grasshoppers and not others,” she said. “Spiders do well when there is abundant prey and vegetation.”

Although irritating, spiders are beneficial to the environment and should be tolerated if possible. Most are beneficial predators that feed mainly on insects. According to the University of Minnesota, spiders can be broken into two groups based on how they capture their prey. Hunting spiders do not use webs to capture their food as opposed to web-building spiders that use silk webs to trap potential prey.

Life with arachnids:

The bottom line is that spiders, bees, hornets, and other arachnids are a necessary part of the evolutionary food chain. Actions can be taken to avoid close contact, but the existence of these critters is not going to change. Mild winters and warm, dry summers may be desirable, but they also bring an increase in the prevalence of insects. It is a side effect that will never be eliminated, but can be tolerated.

What species of spiders are

prevalent in the Fargo/Moorhead area?

Common hunting spiders in North Dakota and Minnesota include jumping spiders, wolf spiders, sac spiders, and crab spiders.

– Jumping spiders are medium size and dark in color with bright white or colored spots.

– Wolf spiders are large and usually dark grey or brown. Most have white markings on their abdomen.

– Sac spiders are small and yellow or light colored.

– Crab spiders are small to medium size and can range in color from yellow to red to brown. Their first four legs are long and crab-like, hence their identifying name. Common web-building spiders include house spiders, barn spiders or orb weavers, and grass spiders.

– House spiders are small to medium size and brown or gray. They build webs in undisturbed areas like corners and behind furniture.

– Barn spiders are commonly found outdoors and have swollen-looking abdomens. They construct the round, wheel like webs usually associated with spiders.

– Grass spiders are medium size and brown to gray in color. Their webs are large flat sheets with a funnel for a retreat.

The most infamous spiders are the black widow and the brown recluse, both of which possess a potentially dangerous bite. Neither species is native to North Dakota, although there have been instances when they have been inadvertently transported to the area from other parts of the country.

It is common for unexplained skin irritations to be called a “spider bite.” In reality, spiders are timid creatures and usually bite only in self-defense. Most are active only at night. Many spiders are not capable of breaking the skin with their fangs and most species; especially those found in the Fargo/Moorhead area, contain venom that causes no reaction. Typical reactions to an actual spider bite include localized reddening and various degrees of swelling, itching, and pain.