May 2, 2013
You better not! However, just in case you do I have a line of curative agents perfect for any and all afflicted with such exhibit ennui. The elixirs I speak of are our new L.A. nature exhibits, Nature Lab and Nature Gardens, and they're about to open on June 9! I've written loads of posts about both exhibits, so I thought it might be interesting to have a guest writer this week (I swear it's not because I'm too busy)! Dean Pentcheff from our Research and Collections staff is going to answer the question that everyone will be asking when the Nature Gardens open, who's camping in that tent out there? "Peek between the bushes in the Nature Garden and you’ll see what looks like someone’s overnight camping spot. We do host overnight sleepovers at NHMLA but we don’t do it in the garden (at least not yet). What’s going on here?
Photo by Phyllis Sun The “tent,” as it turns out, is actually an insect trap. It is no coincidence that it looks like a tent. Its inventor, René Malaise, was inspired by watching insects in his own tent while he was on tropical collecting trips. Insects bumping into an obstruction, like a tent wall (or the vertical mesh of the Malaise trap), tend to fly up to escape. The conical top deflects them up further to the topmost part of the cone. There, our arthropod guests find a hole to a plastic jar full of ethanol — their last drink, and a preservative that lets us keep them for the Museum’s collection in good physical condition and with their DNA available for genetic research. Why such an elaborate insect trap in the Nature Gardens? This trap is one of about thirty that we’re setting up between downtown L.A. and the Griffith Park area as part of our BioSCAN project (BioSCAN stands for Biodiversity Science: City and Nature). Our goals are to develop a good inventory of L.A. insect diversity and to see how insect diversity differs between inner urban areas and outer less-urbanized areas. That’s the reason for the mini-weather station next to every trap. Measuring physical parameters like temperature, humidity, soil temperature, and moistness will help us develop explanations for the diversity differences we will see.
Dean explaining BioSCAN The beauty of the Malaise trap, as René Malaise put it in his original publication, is that they can “… catch all the time, by night as well as by day, and never be forced to quit catching when it was best because dinner-time was at hand.” That also means that we’ll have thousands of samples to sort. You can come watch us do it (and volunteer to help, if you want) in the Nature Lab when that opens in June." Thanks Dean So if you're interested in finding out what a robber fly really looks like, and how many of them we've caught in our Malaise trap, stop by the Museum on or after June 9 and ask us...you never know Dean might actually be the scientist you get to talk too. p.s. he's awesome!
June 15, 2012
Last week, Tania Perez, who is on our Museum education staff, found a cockroach crawling on our office wall! Said roach was quickly trapped and contained and was waiting for me when I got back to my office. Here in North America we have 55 species of cockroach (there are 3500 total in the world)! Of these 55 species, six in California are considered pests. The American Cockroach is the largest of these six roaches, with individuals reaching a maximum of 2 inches in length. Surprisingly, this roach isn't from America at all. It actually native to Africa. The species is also known as the ship cockroach and has hitched rides on ships traveling from Africa to the U.S. A likely apocryphal story, it paints the picture in such a way as to imply it was slave ships during the 1600s that inadvertently transported these insects to our shores. Although this roach is sometimes found in our homes (or on our office walls) it is much more often found living in sewer tunnels, steam vents, and industrial buildings. They are prolific breeders and, according to UC Davis, a "female and her offspring can produce over 800 cockroaches in one year." Females produce egg cases that are small, brown, and bean shaped. These egg cases are deposited in sheltered spaces and after five to seven weeks, they hatch. It takes just over a year for a cockroach to develop to adulthood, and they can live another year as an adult. What makes these creatures particularly impressive is they can go two to three months without any food, one month without water, and even up to a week without their head! That's right. Cockroaches, like other insects, have a decentralized nervous system, and can therefore survive, even walk around, without their head!
After dispatching (aka freezing)...Check out UC Davis' Integrated Pest Management cockroach information sheet!
May 17, 2012
Two weeks ago I told you I'd fill you in when I found dragonfly nymphs in our pond. I wasn't expecting to be able to give you this update so quickly, but SURPRISE, nature moves fast, people! In the last few weeks, I've found more than 50 dragonfly exuviae (the papery exoskeletons shed between molts) attached to the rocks of the pond. Of course, this prompted me to take out my dip net and look for nymphs in the water.Here's a picture of one I found:
Variegated Meadowhawk, Sympetrum corruptum, nymphFound May 5, 2012While I was dipping for the dragonfly nymphs, I found a lot of other macro-invertebrates. The list isn't very long, yet, but includes immature mosquitoes, chironomid midges, mayflies, and predacious diving beetles!
Mayfly nymph found May 5, 2012
Predacious diving beetle larva found in pondMay 4, 2012
I also found an adult predacious diving beetleonMay 5, 2012
March 9, 2012
I was recently out and about in the garden and found some fascinating insects, Keelbacked Treehoppers, Antianthe expansa. They were on some of our celery plants and are, according to Vanessa Vobis Master Gardener and Museum Gallery Interpreter, "a very annoying pest on our tomatoes."
Adult Keelbacked Treehopper on celery(Approximately ¼ inch or 7 mm long)When I found the Keelbacked Treehoppers, all but one were in the nymphal (immature) stage. As nymphs, these insects do not have wings (this is true for all insects—just look at caterpillars, grubs, and maggots), and are bound to the area in which they were deposited as eggs by their mother. The nymphs are often attended by ants, which feed on their sugary excreta and provide a level of defense against the treehopper's predators. Though it should be noted that this is not always the case, there were no ants in attendance around the treehoppers I found, so this isn't a reliable mode of identification. When I found the treehoppers in our Edible Garden, they were feeding on one of the celery plants. They feed on the juices (phloem sap to be exact) inside the plant by inserting their tiny straw-like mouthparts and sucking up the liquid. Although many sources say that these insects cause little, if any, damage to the plants they are on, this is not always the case! When populations of these insects are high enough they can cause serious stunting and sometimes lead to the loss of plants. Many gardeners in our area complain of these pests on their tomatoes. It is not clear if the decline in plant health is due to excessive feeding by these insects or by secondary infections spread to the plant during feeding.
Immature Keelbacked Treehopper photo courtesy of Vanessa VobisFrom a naturalist's perspective these insects are some of the more weird and wonderful. Adult treehoppers (family Membracidae) can be recognized by the prominent enlargement of the pronotum (segment directly behind the head). This enlargement gives many treehoppers a humpbacked or thorny look, hence the other common name for these insects: thorn bugs. However, some tropical species go beyond the thorny devil look and opt instead for something a bit more insectuous! Case in point, the Cyphonia treehopper has a pronotum that mimics an aggressive ant species, which not only looks awesome, but is a great defensive mechanism against predators.
Cyphonia treehopper with ant-like pronotumimage from Nicolas Gompel/Nature
February 23, 2012
Last week, Jany Alvarez, one of the Museum's Guest Relations staff, was sitting at the bus stop adjacent to the North Campus. While she was waiting for her bus, she saw an interesting sight—a caterpillar crawling along the sidewalk! Thinking that the caterpillar would be better off on a plant than on the cement, she picked the caterpillar up and placed it carefully on a Dudleya plant on the Living Wall. Later that day, another Guest Relations staffer watched the caterpillar pupate! By the time word travelled to me, the pupa looked like this:
Yellow pupa on DudleyaWhen I came into work on Tuesday morning, the pupa had changed color! I took more pictures and went back to my office to identify it.
Close up of pupa. Note the small horn-like structureThe pupa belongs to a butterfly regularly seen in and around Los Angeles, the Cloudless Sulphur, Phoebis sennae. The Cloudless Sulphur belongs to the Pieridae butterfly family, which includes White, Sulphur, and Orange-tip butterflies. The most common butterfly in this family is the Cabbage White, which flies year round in our area and is a pest on vegetables such as cabbage, kale, and broccoli. In contrast the caterpillar of the Cloudless Sulphur feeds on cassia plants (genus Senna) and is often seen in our local deserts where the two California native species in this genus grow naturally. The altered nature of Los Angeles is such that non-native cassias are now common all over our area. They've been planted in various places like your neighbor's backyard, your local park, and even in the North Campus. The bus stop where Jany found the Cloudless Sulphur caterpillar is only 20 feet away from a few feathery cassias, Senna artemisioides, which were recently planted in the North Campus!I guess our premise for developing habitat around the Museum is correct—plant it and they will come!
Male Cloudless Sulphur from our Entomology Collection
January 20, 2012
There are over 150,000 species of flies in the world! Most visitors who come to the Museum can name only a few of these flies (house fly, horse fly, or mosquito for examples) and many hold the belief that we would be better off without flies in our world. On Wednesday, January 18, we found a fly that I am sure will help you realize that all flies can't be cast as "bad" characters — I introduce the humble aphid eating flower fly, Eupeodes volucris.
Female Eupeodes volucrisPhoto taken by Jerry FriedmanWhy do people like these flies and not others? This isn't an easy question to answer, but I'll have a go... First of all, these flies eat aphids and as any gardener will tell you, aphids are a serious garden pest. Secondly, they belong to a family of flies known as “flower flies” so called for their proclivity to visit flowers and suck down nectar. Thereby they play a role in pollination. Finally, if you look closely at these small flies you'll see why a lot of geeky people, like myself, think they are quite beautiful. Not only are they brightly colored and highly patterned, when their eyes catch the sunlight just right they have an iridescent sheen! Although I might add that E. volucris isn't as flashy as its close relative, the aptly named stripe-eyed flower fly, Eristalinus taeniops, also a native to the Los Angeles area.
Stripe-eyed flower flyPhoto courtesy of What's That Bug websiteHow does a fly eat an aphid? It is actually the larval stage of the fly, or maggot that chows down on aphids. Much like immature ladybugs they trawl through a sea of aphids on a plant and chomp any that get in their way! Though they don't have quite the same look as a ladybug!
Flower fly maggots eating oleander aphidsPhoto courtesy of What's That Bug websiteTo find out more our local flower flies, swing by the Museum gift shop to get a copy of our latest entomological publication, Flower Flies of Los Angeles County.
Thanks to Brian Brown and Jim Hogue for supplying fly information and identifying the fly specimen.
January 5, 2012
Last Friday two Indian walking sticks, Carausius morosus, mysteriously showed up inside the Museum! They didn't escape from the Insect Zoo (we've never kept this species of walking stick before), and we haven't been able to find out exactly how they got here. What we do know is that the insects were discovered after a visitor felt one "fall" on his arm, and then promptly reported it to a staff person.
One of the Indian walking sticks found in the Museum!Indian walking sticks, a.k.a. laboratory walking sticks, are one of the most common walking sticks around. They are often kept as pets and classroom teaching tools, and their eggs can even be purchased on eBay for fish food! Surprisingly these insects have recently established themselves in our area through inadvertent or purposeful introductions. How does one inadvertently introduce stick insects into the environment?Indian walking sticks can reproduce parthenogenetically, that is without sexual reproduction. Therefore females can produce eggs regardless of the presence of males. The eggs are very small, about 3mm in length, and look a lot like tiny stones. Female sticks lay their eggs by dropping them directly to the ground, where they accumulate in the leaf litter. When they are in captivity, fecal material, partially chewed leaves, and eggs accumulate very quickly at the bottom of walking stick enclosures. To keep the insects clean and safe it is important for owners to clean this material out on a regular basis. For the untrained stick keeper, it is very easy to inadvertently discard eggs. Often this will be directly into the trash, or maybe even into the backyard compost pile. Paired with purposeful introductions, "I can't keep this pet anymore, I'm sure it will be better outside," is it any wonder that these insects have established themselves in numerous areas around Los Angeles?
Indian walking stick eggs (photo courtesy of Dr. Arakelian)According to Dr. Gevorak Arakelian, Senior Biologist in the L.A. County Department of Agricultural Commissioner, Indian walking sticks have recently been downgraded from a B rating to a C rating. This means that they aren't viewed as serious pests that need to be eradicated. However, for gardeners and the nursery industry these insects can still be troublesome. They eat a wide variety of landscape plants including rose, bramble, camelia, hibiscus, geranium, oak, and English ivy (the list goes on). Next time you find mysterious chew marks on your rose bush, take a closer look and see if you can find a walking stick hiding nearby.For more information check out Dr. Arakelian's Indian walking stick fact sheet.
December 23, 2011
On the Twelfth Day of Christmas the North Campus gave to me... Twelve skippers skipping
Eleven pill bugs pillaging On the Twelfth Day of Christmas the North Campus gave to me... Twelve skippers skipping
Eleven pill bugs pillaging
Ten fritillaries a-feeding
Nine gulls a-diving (dumpster diving that is)
Eight mantids a-milking
Seven caterpillars a-crawling
Six ladybugs a-laying
Five phorid (fly) wings
Four calling crows
Three French hummingbirds
Two turtle fox squirrels
And an oak gall in an oak tree!
Wishing you a happy holiday season!
November 9, 2011
No it's not the title of a horror film, Children of the Earth is actually one of the many common names for Stenopelmatus fuscus. Other names lovingly given to this insect are Jerusalem Cricket, Potato Bug, Skull Insect, and my personal favorite, Devil's Baby! Earlier this week Sam Easterson found one in his front yard and captured this picture and footage.
Are you Looking at Me?These crickets are very common in Los Angeles. Consequently, my colleague Brian Brown, the Museum's Curator of Entomology, and I get calls about them all the time. I most often get calls after heavy rains, when these crickets come up from the depths of their soily abodes. They are stellar diggers (Check out their fossorial front legs, modified for digging) and live most of the summer months deep underground to escape the heat. Aside from their enlarged digging legs, their most obvious feature is their highly-domed head, which gives them an alien-like look. To continue the alien theme, these large heads contains multiple "brains!" To be scientifically correct they are actually cerebral ganglia, or masses of nerve tissue, which control the action of the chewing mouthparts, eyes, and antennae. Maybe I should propose a new name for this cricket, Alien's Devil Child?
November 4, 2011
Earlier this week I saw my first praying mantis in the North Campus! I was walking back from lunch at USC and there she was right in front of me on the path.
Female Mediterranean Mantid, Iris oratoria, running for coverI knew she was a female because of her enlarged abdomen, males have much narrower abdomens and also longer wings. As I got really close to her to capture this picture, she went into her defensive posture. She reared up on her hind legs, extended her raptorial (modified for capturing prey) front legs, and flashed her brightly patterned black and yellow hind wings. She stayed in this posture for about 15 seconds and then ran for cover in the plantings. Hopefully she'll lay an egg case and we'll have baby mantids in the spring!
Mediterranean Mantid defensive posture (image courtesy of What's That Bug website)