Friday, October 31, 2008

Hallowe'en Bug News

We saved the scariest and most disturbing bug news to share today, in honor of all the little vampires and ghouls out there. This strange but true news comes from Discover Magazine's blog, in an article here. Apparently, scientists have discovered a new tendency in bugs: they crave blood! For mosquitos and bed bugs, this is not unusual. But these are insects that generally have been attracted by sweet substances, and are now looking for salt.
According to the article, research teams studying insects in Peru became puzzled when they were attacked by swarms of tiny bees. The bees were trying to get a taste of their sweat! Animals, and apparently even insects, need salt to maintain water balance in their cells.
Armed with new evidence and theories to test, the scientists baited ants on the Peruvian forest floor with vials of both sugary and salty water, then counted the ant species they baited. Ants living close to the ocean, and thereby near a source of salt, preferred the sugar. Inland ants preferred salt. Further, the scientists found the salt cravings were only seen in vegetarian ants, as carnivorous ants got enough salt from the bodies of their prey. Their report was published in the Proceedings of the National Academy of Sciences.
Which brings us to vampire moths. In another study, entomologists researched a population of fruit-feeding moths (Calyptra thalictri) which evolved the habit of feeding on blood. These moths, native to Russia, use their long, sharp  tongues to pierce human skin now instead of peaches and pears. They have been observed sucking blood from the scientists' hands for more than 20  minutes at a time. According to the Discover article, only male  moths engage in blood-feeding. The scientists suspect they are offering the salt from the blood as a gift to females during copulation. Happy Hallowe'en!

Thursday, October 30, 2008

More on Spiders - Spooky or Friendly?

In light of the Hallowe'en festivities all around us, we will share more information on spiders today, with a look at what makes them spooky and  how we can focus on their more redeeming qualities. Spiders have amazingly bad press. They have been cast as villains in horror movies, murder mysteries, and even fairy tales! The truth is that most spiders are harmless, and extremely beneficial. Part of the delicate balance of nature, spiders eat harmful and nuisance insects in our yards and homes. As noted in this week's bug quiz, only two varieties of spiders in San Diego County can be considered dangerous: The black widow and the desert recluse. Of those two, the black widow is most common. The desert recluse is, as its name suggests, reclusive - preferring to live in remote and unpopulated areas. Bites delivered by these two spiders may be painful, but reactions vary widely and are most often no more serious than a bee sting.  So how can you avoid the scariest spider in San Diego? The more you know about the black widow, the easier it will be to avoid their bites. 
Black widow spiders (pictured above) are shiny, black spiders with thick legs and bulbous abdomens, on the underside of which they sport a distinctive red hourglass marking. Females are around 1/2-inch long, males much smaller - around 1/4-inch, with a longer, narrower abdomen and somewhat longer legs. Black widows are shy, preferring to build their webs in dry, protected locations. Outdoors they are most often found in woodpiles, under rocks, beneath benches, under decks, etc. The web of the black widow is thick, sticky and irregular in shape. If you see this kind of web, use care in knocking it down - although spiders typically have eight eyes, their vision is not good, so they are most often alerted by vibrations. If you encounter black widows or their webs inside (very rare) use a vacuum to remove spiders, webs, and egg sacks - then seal the vacuum bag and discard immediately. Like so many other pests, spiders may be looking for harborage as the weather cools down - so inspect doors and screens to be sure your house is secure. And wear shoes outside! If you are seeing too many spiders in the house or yard, call a pest professional. But remember - spiders eat flies, moths and mosquitos, so as long as they are not bothering you or multiplying out of proportion, let them do their job.
Finally, although we don't see a lot of big scary spiders here, you can rely on videos and news reports from around the world to see the kind legends are made of. Check out the photo and article on a bird-eating spider from Australia here. Take a look at a photo and video of camel spiders here. Or check out the truly scary Monster Spider Web found in Texas here. Enjoy!

Wednesday, October 29, 2008

Quiz Answers: Spiders!

Pictured: The eyes of a brown recluse spider

Spiders have been big news in San Diego this year. We continue to receive more calls for spiders than usual - indicating a population surge for spiders. Perhaps it is the weather, or maybe more people have been putting out bird seed. Whatever the reason, it is not necessarily a bad thing! The overwhelming majority of household spiders are good for the ecological balance of your yard. Because of the bad press of a scary minority of spiders, it seems the whole group has a bad aura. Here are the answers for yesterday's quiz:

1. The number of spider species that have been identified world wide is (d) 37,000. This is of course an approximate number. But taking that number into consideration, it should become immediately apparent why we are not always able to identify spider samples. What we can do is rule out the most dangerous of local spiders. Which brings us to:

2. The number of spiders in San Diego County which deliver poisonous bites: (a) two. According to the County of San Diego's Pest Management website, "The only poisonous spiders in San Diego County are the Black Widow and the Desert Recluse." From the same source, the Desert Recluse is not the same as the Brown Recluse - and it is found mainly in the Sonoran and Mojave deserts, the foothills of the lower Joaquin Valley and areas close to the Mexican border. Check their excellent site here for more information on these two local spiders with attitude.

3. The largest spiders in the world can be found in (c) South America. In fact,  South American Tarantulas are about the size of a dinner plate - around 12 inches in diameter, with 1-inch fangs. For a video on these "killing machines" see the video here. The good news? Their sting is usually  no worse than a bee sting. There are no reported cases on human death by tarantula!

4. The most  reliable distinction between a brown recluse and a wolf spider is (d) the number of eyes. While it is true that the brown recluse has a dark, violin-shaped marking behind the head (on its cephalothorax), many brown spiders, including varieties of Wolf spider, have markings that could be interpreted as looking like a violin. While the 6 eye pattern of the brown recluse is easy to see with magnification, we do not recommend looking closely at the eyes of a live spider! Some spitting spiders do have a similar eye pattern, but do not have a violin. See the photo above for the distinctive eye pattern of the brown recluse. For more on how to identify the brown recluse, visit the website here. To view a map of where brown recluse spiders are found, see here. Note: The city of San Diego is NOT identified as a brown recluse zone on the map.

5. The largest family of spiders is (a) Jumping spiders (Salticidae), followed by Sheet Weavers (Linyphiidae) and Orb-weaving spiders (Araneidae). Using a well-developed hydraulic system which extends their limbs by altering the pressure of body fluid, jumping spiders can jump 20-60 times their body length as they pursue prey. They typically have eight eyes in two or three rows. Tarantulas are the largest of spiders, but not the largest family of spiders.

6. The best way to avoid spider bites is to (b) wear shoes outdoors. Keeping exterior house doors closed is also a good idea, but unless you are able to close even the smallest breaches under doors and around windows spiders are likely to find their way inside. 

7. The correct FALSE answer is (b) - all arachnids are spiders. In fact, all spiders are arachnids - but not all arachnids are spiders. One case in point is the Daddy-longleg, which is an arachnid but not a spider.

8. This is a trick question. Remember, this is the Hallowe'en edition of the quiz! Depending on what species of spider you were, and how tall you stand proportionally, you might be able to jump (a)85 feet, (b) 130 feet, (c) 260 feet (best answer) or (d) 350 feet. Remember, there are around 37,000 varieties of spiders in the world, with various abilities. Now that you know a little more about spiders, we hope you will not  jump when you see one! For more information in a short video about spiders, click here.

Tuesday, October 28, 2008

Tuesday's Quiz: Spiders!

Just in time for Hallowe'en, we present Tuesday's Quiz with a focus on spiders this week. Are they the scariest bugs? Certainly one of the creepiest! Test your knowledge of arachnids today and find the answers in tomorrow's blog.

1. How many spider species have been identified worldwide?
a. 1,600
b. 16,000
c. 3,700
d. 37,000

2. Of the many spider species in San Diego County, how many deliver poisonous bites?
a. 2
b. 4
c. 6
d. 8

3. Where would you find the largest spiders in the world?
a. Africa
b. Australia
c. South America
d. Asia

4. The spider pictured above is a Wolf spider, fairly common in North America and often mistaken for the Brown Recluse spider. What distinguishes a wolf spider from a brown recluse?
a.  Brown Recluse are bigger
b. Wolf spiders are nocturnal
c. Brown Recluse have a distinctive marking behind the head
d. Wolf spiders have more eyes

5. The largest family of spiders is 

6. The best way to avoid spider bites is to
a. Wear strong perfume
b. Wear shoes outdoors
c. Keep doors closed
d. Hang garlic around your neck

7. Which of the following is false?
a. all spiders are arachnids
b. all arachnids are spiders
c. arachnids do not have antennae
d. Daddy-longlegs are not spiders

8. If you were a spider, how high could you jump, proportionately?
a. 85 feet
b. 130 feet
c. 260 feet
d. 350 feet

Wednesday, October 1, 2008

Quiz Answers: Weird Bug News

Here are the answers to yesterday's quiz on weird bug news. These are actual news stories we gleaned off the internet - so you know they are true! Have fun reading the answers, and perhaps learning a bit more about the wonderful world of insects.

1. From Liverpool, England, we have a story about a 50-foot mechanical spider, placed on one of the biggest buildings in town by a French arts collective called La Machine. The three-story arachnid is lovingly named (d) "La Princess." We are not sure why they chose the name (we like our fake names better) or the location for this giant bug, but it makes a great photo op (see photo above). 

2. From Tokyo, a Japanese monk accidentally set fire to his temple while trying to eradicate (b) hornets. The story, from, reports the Buddhist monk had lit rags attached to a stick and tried to apply it to the hornet nest in the temple - but dropped the torch when the hornets attacked him. So much for attempting your own pest control! 

3. From Eagle Rock, California, a school teacher was recently praised by PETA for (a) appointing an insect monitor to prevent the squashing of bugs in the classroom. The teacher, Melodie Conrad, said she is  not exactly an insect rights activist, but she wanted to emphasize to the children that there is already too much violence in the world.

4. From New Jersey, another man's attempt at do-it-yourself pest control ends in disaster. According to the story on Isias Vidal Maceda was not injured but destroyed 80 percent of his apartment in Eatontown when he attempted to (a) spray for roaches. Although the article does not give details, we suspect Mr. Maceda may have used an over-the-counter bug bomb without turning off pilot lights, or perhaps used too many. Whatever the details, the bug spray reportedly ignited a blast that started a fire in the apartment and caused smoke damage in the apartment above.

5. From Pennsylvania, via an article on the Fox News website, (c) giant beetles from Taiwan were discovered in a postal package. The contents were listed as toys, gifts and jellies - but when the postal workers heard scratching noises coming from inside the box, they became suspicious. The parcel was X-rayed then opened, revealing 26 of the largest beetles imaginable - averaging 5-6 inches in diameter. For the record, it is illegal to ship live beetles into the United States without a permit from the Department of Agriculture, as they can cause a great deal of damage to fruit and vegetable crops.

6. From Brazil, ants have been observed (c) sacrificing themselves to seal the entrance to their nest. A few ants, probably the older ones in the colony, remain outside the entrance to kick sand over the hole until it becomes invisible. Being unable to reenter the nest, these ants die from exposure to the cold. It is apparently a pre-meditated task, performed each night at sunset - whether or not there is a clear danger from predators. The covering of the entrance takes about 50 minutes, as the ants heroically kick sand backwards with their hind legs. 

7. According to an article in the Marin Independent Journal, a 250 million-year-old fossilized dragonfly had a wingspan of (b) 28 inches! The article goes on to note that dragonflies can be beneficial to gardeners, feeding on other more harmful garden pests. In case  you were wondering, the "dragon" portion of their name comes from the fierce jaws they use to catch their prey. And as mentioned in a previous post, they are the fastest of all insects, able to reach speeds of up to 60 mph.

We hope you have enjoyed this brief detour into the wide world of bugs. More local pest items tomorrow.