by Angie Williams, JRA Database and Web Coordinator
 |
| photo by Peter Baer |
As Halloween draws close, yards in your neighborhood may become
littered with ghosts, zombies and huge creepy-crawly spiders in order to strike
fear into the hearts of young and old alike. Although the majority of spiders
in Virginia do not cause harm to humans, there are a few that do. One of the
most known, fitting perfectly into the all-black Halloween theme, is the Black
Widow.
Black widows (Latrodectus mactans) are so named for their black
coloring and because females often kill and eat their ‘spouse’ after
mating. These spiders can be easily
identified by the red hourglass shaped mark on the underside of their abdomens.
The venom of the black widow is reported to be much more potent
that rattlesnake or cobra venom. Although it is rare for a healthy human adult
to receive a fatal dose, in the event of a bite, it is recommended to receive
medical attention immediately. The venom may cause muscle aches, nausea, and
difficulty breathing. Very rarely does their bite cause death in humans; this
is mostly due to the development of antivenin. Fortunately, improvements in
household plumbing have reduced the incidence of bites to humans!
 |
| photo by Jeremy Hall |
The black widow preys on a variety of insects and sometimes
other arachnids. This makes them carnivorous and cannibalistic! When their prey has become ensnared in their
web, they wrap it in silk and deliver a deadly bite with their fangs. The venom
takes approximately ten minutes to take effect. Once the prey has stopped
moving, the spider injects it with digestive enzymes that liquefy the dead body
so it can be sucked up by the spider.
These spiders are partial to dark areas and wood piles, so this
fall when stacking wood or clearing areas take care not to be the black widow’s
next victim.
References:
No comments:
Post a Comment