Sunday, June 20, 2010
Saturday, June 19, 2010
Tuesday, June 15, 2010
International Tour II
Tarantula on our Morning Walk
Most spiders are small, inconspicuous arthropods which are harmless to humans. Their beneficial role in keeping insect populations in check far outweighs the hazard posed by the few spiders that occasionally bite humans. Very few of the nearly 900 species of spiders in Texas can hurt people. Only two groups--recluse spiders and widow spiders-- are considered poisonous to humans.
Tarantulas, jumping spiders, wolf spiders and some other spiders worry people who mistakenly believe they are seriously poisonous. Although these spiders are often large, hairy and formidable-looking, their bite is typically less harmful than a bee sting. People who are extremely allergic to spider venom, though, react severely to any spider bite.
Many people have a phobia of spiders. However, knowing how to distinguish harmless from dangerous spiders, how to prevent them from entering the home and how to control those that do enter can prevent needless concern and reduce the chances of harm to humans.
Tarantulas in Texas are members of the hairy mygalomorph family in the genus Aphonopelma. These large, hairy spiders are brown to black and more than 3 inches long when full-grown. Females, larger than males, have abdomens about the size of a quarter.
Tarantulas hunt at night and spend the day under rocks, in abandoned mouse burrows or in other sheltered areas. They may be seen in the evening or late at night along country roads or trails. Migrating male tarantulas can be commonly seen for a few weeks in early summer. This migration’s purpose is not completely understood, but it may occur as males seek mates.
Tarantulas are sometimes kept as pets and can become quite tame. Although they can be handled, be careful, because they can quickly become disturbed and pierce the skin with their fangs on the chelicerae. The hair on some tarantulas may irritate the skin, so take care when handling them.
Tarantulas need a constant supply of water in a flat dish into which they can lower their mouths. They eat live crickets, mealworms, caterpillars or other insects and can go for several weeks without food, sometimes refusing to eat before molting. Tarantulas can crawl up glass and escape through small openings, so they must be kept in a container with a good lid.
Sunday, June 13, 2010
Spring Storms Over Austin
Another batch of beautiful lightning storms hit the Austin Area. The lightning was stunning once the massive storm moved through the area. But this time the lightning had a yellowish tint to it. This is the first time I've recorded such colors. So I did a little research on it and found ..... the color was yellow because the storm was far away. Just as the moon appears yellow when near the horizon, the shorter wavelengths of the light from the lightning were scattered out by the atmosphere, leaving the longer wavelengths(yellow, red) to be seen. The sun, when right on the horizon, sometimes appears red because there is sufficient water vapor, aerosols, and other pollutants to scatter out even yellow light. The lightning, being both far away and in proximity to a lot of water vapor and water droplets (over the lake and associated with a storm) was seen as yellow. As far as the color of lightning, even when seen close, natural lightning usually appears somewhat yellowish.