Backyard Orchard News
Human blood--it drives mosquitoes wild.
Today Marlene Cimmons of the National Science Foundation (NSF) spotlights chemical ecologist Walter Leal, professor of entomology, University of California, Davis, on the LiveScience Web site.
This interesting feature takes a behind-the-scenes look at Leal, a Brazilian-born scientist trained in three countries: Brazil, Japan and the United States.
His research, partly funded by a NSF grant, has received international acclaim. Last year he was elected a Fellow of the 6000-member Entomological Society of America, a prestigious honor reserved for only 10 or fewer scientists a year.
Leal, who focuses his research on how insects detect smells, is not shy about being a human subject.
Or human pincushion.
Cimmons wrote about how Leal "rolled up his sleeves" when he and his colleagues were looking for the substance that would lure mosquitoes into a blood meal. "And they found it--nonanal, a substance made by humans and birds that creates a powerful scent that Culex mosquitoes find irresistible."
Leal also recalls the time when he was searching for beetles in Mexico and mosquitoes went after him with a vengeance.
"They'll go through anything, even jeans, as long as they know there is a blood vessel on the other side," Leal told Cimmons. "They can sense the heat."
Indeed, some folks just seem to attract more than their share of mosquitoes.
Only the female mosquitoes bite--they need a blood meal to develop their eggs.Related links:
UC Davis Researchers Identify Dominant Chemical That Attracts Mosquitoes to Humans
Groundbreaking Research on DEET
It’s raining in northern California like the proverbial cats and dogs--and all the more reason to think of vacations.
Extension apiculturist Eric Mussen, member of the UC Davis Department of Entomology faculty, received a query last week from a family planning a camping trip to a public park in the Midwest.
A daughter is allergic to bee stings, so the family wanted to know two things:
1. Is there any way to find out what a bee population is in a specific area?
2. How can we avoid bee stings?
His answers are informative:
Is there any way to find out what a bee population is in a specific area?
Usually, the only records that are kept deal with the number of colonies registered by the beekeepers in a state once a year. If the beekeepers are commercial beekeepers, they are likely to move the colonies around for purposes of crop pollination or producing honey crops. Unless you knew all the beekeepers and their patterns of operation, there is no way to know where the colonies are.
If this is a good honey producing area, beekeepers might be moving their bees into it. You could call the park (if it is one) and see if they allow beekeeping on the park grounds.
Even if they don't, if there is good bee forage in the area (nectar and pollen), some honey bees are apt to be living around the area in "feral" colonies--not managed by anyone.
How can we avoid bee stings? Best preventative measures?
Honey bees do not tend to sting anything very far from the nesting location, unless you happen to step on one, etc. They are busy collecting water, nectar, pollens, or propolis (plant resins they use to glue things in the hive.) If something comes near the nesting location, and the bees respond to the approaching threat, then there might be some stinging.
What are the best preventative measures? This pertains to wasps, too, which sting more people in the woods than honey bees ever do. Keep your eyes open for "directed" flight by insects in an out of a specific spot. That is likely to be the nest entrance. Keep away from there.
If bees or wasps come flying out toward you, don't swing at them or try to blow them away from your face. You'll get stung immediately. If you are not yet stung, just stand very still for a moment, then ease yourself out of the area with no flailing or swinging of the arms, etc.
Put a lot of distance between you and the nest without running.
If they are all over you and stinging, then run first and work on the stings later. Honey bee stings stick in your flesh and give off "alarm pheromone," which leads to more stings in the same place. You do not want to continue to be a target.
If stung, look for the sting when you get a chance. If it is honey bees, the sting will be there. Scrape it off with a finger nail, before all the venom is pumped into the skin.
Honey bees are attracted more to yellow and blue than to other colors. Honey bees treat red and black as black. Black is bad if bees are stinging in the area. Pastel and white colors usually are best around bees.
Honey bees are attracted to odors reminiscent of lemon and are shocked by the smell of bananas--just like their alarm odor. (The aroma of bananas is similar to the scent of a bee's alarm pheromone.)
Final thought, even if there are bee hives or nests around, hardly anyone ever gets stung by them. They do their thing and you do yours, and there should not be any conflict under normal circumstances.***
For more information on bee stings, read the bee sting advice that appears in his newsletter, from the UC Apiaries, a publication Mussen launched in 1976. He also writes the equally informative Bee Briefs. These publications are archived on the UC Davis Department of Entomology Web site.
Flight of the Honey Bee
Check out the Life After People series airing on the History Channel. Next week the series will include the segment, "The Last Supper" and include an interview with entomologist Lynn Kimsey (right), director of the Bohart Museum of Entomology and professor and vice chair of the UC Davis Department of Entomology.
The segment is scheduled to air Thursday, Jan. 26. She's also scheduled to appear in another segment on Feb. 2. (Check the History Channel for local listings.)
A TV crew trucked to UC Davis last October to film Kimsey, a noted authority on insects. Indeed, she's virtually surrounded by insects; the Bohart Museum contains more than seven million insect specimens.
Globally, we have about a million DESCRIBED insect species, with millions more yet to be discovered. In fact, some entomologists estimate there may be as many as 30 million undiscovered species out there.
The Life After People series "begins in the moments after people disappear," the Web site indicates. "As each day, month and year passes, the fate of a particular environment, city or theme is disclosed. Special effects, combined with interviews from top experts in the field of engineering, botany, biology, geology, and archeology provide an unforgettable visual journey through the ultimately hypothetical."
"The Last Supper" segment takes a look at the world of food. "Destructive forces turn supermarkets into breeding grounds for insects and rodents. Some foods last forever. Da Vinci's The Last Supper suffers due to an unusual paint ingredient. Some of man's agricultural staples succumb, while a surprising plant thrives. Exquisite restaurants atop of Taipei 101, the second tallest building in the world, collapse."
Foods that last forever? No doubt honey is one of them. Jars of honey found in Egyptian tombs date back 3300 years.
And the quality of the honey? Still edible.
After all those years.
Bee and Honey
But they are fleeting butterflies.
For the past 35 years, noted butterfly expert Arthur Shapiro (top right), UC Davis professor of evolution and ecology, has documented the prevalence--or absence--of 159 species twice a month at 10 sites from the Suisun Marsh to the Sierras. His massive database, unprecedented among lepitopterists, is part of his popular butterfly Web site.
Last week his database and the plight of the butterflies received international attention via a paper published by lead author Matt Forister in the Proceedings of the National Academy of Sciences (PNAS). The study showed that climate change and land development are taking their toll on butterflies.Forister (lower right) who studied with Shapiro at UC Davis and received his doctorate in ecology from UC Davis in 2004, is now an assistant professor in the Department of Biology at the University of Reno, Nev. (You can watch his Webcast on butterflies given last November at a noonhour seminar in the UC Davis Department of Entomology.)
In many respects, butterflies are to the environment what canaries are to coal mines.
Titled "Compounded Effects of Climate Change and Habitat Alteration Shift Patterns of Butterfly Diversity" and the work of eight authors, the research paper documents the disastrous effects of habitat loss and climate changes.
Shapiro, author of the book, Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, says what shocks him is the decline of once common species in the flatlands.
Indeed, prospects for some alpine butterflies, including the Small Wood Nympth and Nevada Skipper, he says, look bleak, too. As he told Contra Costa Times reporter Suzanne Bohan, in her Jan. 19th news article:
"There is nowhere to go except heaven."
Western Tiger Swallowtail
Pull out the bottom tray (floor) of a beehive and you're likely to see lots of bee droppings, a little pollen, a few mites, a few dead bees and...a few scurrying ants.
Ants find a bee hive nice and cozy, especially in the winter as temperatures drop.
Beekeeper Elizabeth "Liz" Frost of the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis, who helps tend the hives never knows what she'll see during a colony inspection.
"Look," she pointed out, "see the ant carrying pollen?"
The tiny little critter hustling a heavy load of pollen made for an interesting photo.
Ants and bees are both social insects and belong to the same order, Hymenoptera. Bees and ants are sometimes called "superorganisms" as they employ a division of specialized labor, working together to support the colony for the good of all.
Ants in the bee hive, though, are a nuisance.
Off to the Nest