Do you have Museum Malaise?

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 NHM 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!

I Have a Cockroach in My Office!

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!

 

Trapped!

After dispatching (aka freezing)...



Check out UC Davis' Integrated Pest Management cockroach information sheet!

Pond Babies: Dragonflies and Diving Beetles

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, nymph

Found May 5, 2012

While 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 pond
May 4, 2012

I also found an adult predacious diving beetle

on

May 5, 2012



Thorny Devils in the Garden

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 Vobis

From 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 pronotum

image from Nicolas Gompel/Nature



First Clouded Sulphur Butterfly Pupa in North Campus

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 Dudleya

When 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 structure

The 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

Aphid Eating Flower Fly Found in North Campus

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 volucris

Photo taken by Jerry Friedman

Why 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 fly

Photo courtesy of What's That Bug website

How 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 aphids

Photo courtesy of What's That Bug website

To 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.

Walking Sticks Mysteriously Appear in Museum

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.

The Twelve Days of Christmas

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!



Niña de la Tierra: Children of the Earth

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?

Praying Mantis

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 cover

I 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)

Today on the North Campus

I went out for a walk around the North Campus today and this is what I saw:

They are filling the pond to make sure there aren't any leaks and that the waterfall cascade is level.

Underneath the pedestrian footbridge is the best spot for mushrooms. I think this is a morel, Morchella esculenta. I am consulting with some mushroom experts to see if they can make a positive identification.

Apparently the Monarch caterpillar I found two weeks ago made its pupal case on a wall. I just love how green they are!

Flesh Flies and CSI!

Since it's October I decided to focus the rest of this month's posts on Halloween inspired themes. Wracking my brains for topics, I realized something I saw last week in the basement would fit the bill nicely. Flesh flies!

Generally the Live Animal Program doesn't keep flesh flies but Shawna Joplin, Coordinator of Animal Care and Education, brought them in as a new food source for our spiders in the Spider Pavilion (open through November 6). The species we are keeping are grey flesh flies, Sarcaphaga bullata, which get shipped to us a pupa. After about a week and a half the adult flies emerge from the puparium and are ready for us to release into the pavilion.

Grey flesh fly pupae

Our adult flesh flies feeding on banana

Flesh fly emerging from its puparium

Contrary to their common name, adult flesh flies don't feed solely on flesh. In fact they just as often eat nectar and other sugary items such as rotting fruit. All flesh flies in the family Sarcophagidae are larviparous, which means they incubate eggs internally and then seemingly give birth to live young, or maggots. It is the place of "birth" that gives these flies their common name—they are deposited on any available dead flesh! In fact these flies are some of the first visitors to roadkill, discarded innards, and even murder victims. Putting these flies to work, forensic entomologists have painstakingly studied their lifecycle, so they can assist Crime Scene Investigators in determining time of death. Because they rapidly discover a body and their development times are predictable under particular environmental conditions, the time of death can be calculated by counting back the days from the life stage of the flies found living on the body.

Next time you feel like seeing these maggots in person, just do what some of our Adventures in Nature campers have done—put out a piece of store-bought liver and wait for the maggots to show up! WARNING: This is smelly, messy work! Lots of other species of flies, beetles, and other creatures are likely to show up too. Are you prepared?

Happy Early Halloween!

North Campus Monarchs

Yesterday afternoon myself and number of other staff members braved the heat to continue our survey of North Campus insects. On the heels of last week's Gulf Fritillary discovery, I found the site's first Monarch butterfly caterpillar, Danaus plexippus!

Monarch butterfly caterpillar

As soon as I saw the caterpillar I knew it was a Monarch: There isn't another caterpillar in our area with such yellow, black, and white banding. Also, the caterpillar was found on a narrow-leaved milkweed plant, Asclepias fascicularis, which is one of the food plants of this well-known species.

Based on its size, this caterpillar is in the second to last caterpillar stage (4th instar). Over the coming weeks it will molt to the last and final stage (5th instar), and then turn into a chrysalis.  In time for its fall migration, the adult Monarch will emerge and make its way to an overwintering site somewhere along the coast.

In the coming years I hope to tag and track the adult Monarchs that emerge in the North Campus, so we can determine the exact location(s) of our Monarchs' overwintering site(s). Tagging Monarchs is an easy process that in no way hurts the butterflies. The adults are collected with a net and then carefully held while a small sticker (approximately 2% of the butterflies weight) is attached to the hind wing of the butterfly. The butterfly is then released and flies onto its overwintering site. When the Monarchs dies the following spring (after mating) the tags are hopefully retrieved and we can answer the question, where do our North Campus Monarchs overwinter?

Demonstrating how to handle a Monarch for tagging

First Caterpillar Record for North Campus!

The last few weeks I have been spoiled with bloggable stories, but this week I needed inspiration. I took a stroll out to the North Campus to see what I could find, and was excited to happen upon the first North Campus caterpillar.

The caterpillar I found was in the last and final "J stage" of its larval lifecycle, just about to pupate. 

Easily recognizable, Gulf Fritillary caterpillars are striped and spiny.

24 hours later the caterpillar had metamorphosed into the pupal stage, aka chrysalis.

If you look close, you can see the developing wings.

This pupa is a Gulf Fritillary butterfly, Agraulis vanillae, native to Mexico and the southeastern United States where its passion vine food plants are also native. However, this species is now very common to our region because of all the passion vines that have been planted in yards, parks, and also in the North Campus! The species of passion vine I found the caterpillar on was Passiflora 'Lavendar Lady' cultivar, which is a cross between P. amethystina and P. caerula.

Typical alien-looking flower of passion vine, 'Lavender Lady' cultivar.

If you want to encourage these butterflies in your own yard, try planting a few passion vines of your own. Here is a list of the other passion vines we plan on planting in the North Campus:

Passiflora edulis
Passiflora caerulea
Passiflora alatocaerulas

Paper Wasps Sting Museum Taxidermist!

When Tim Bovard, the Museum's taxidermist, told me about getting stung by wasps on the fourth floor patio, I had to investigate, especially since I sometimes eat lunch up there. During a much needed afternoon break from my computer, I went in search of the offenders.

What I found on my afternoon foray were some large and impressive nests, definitely worthy of a blog entry. So of course I asked Sam if he would take pictures for me, and I went to work identifying them. 

Common paper wasp nest, Polistes exclamans

The species living on our patio are Common Paper Wasps, Polistes exclamans, which have a widespread distribution through much of the southern United States. These insects construct a papery nest from fibers they gather off dead wood or plant stems. Next time you see a paper wasp on a wooden fence realize it might be chewing off tiny pieces of wood which they will mix with their own saliva to make paper! The nests are umbrella shaped and generally built under eaves or porches, or in similarly sheltered locations. Unlike yellowjackets and hornets, paper wasp nests are not enclosed in a papery shell, which give a really good view into the individual cells.

A view into a brood chamber, can you see the larva?

Sam was also able to get some great video footage of the wasps at work. In an effort to provide the best video documentation ever, Sam nearly sustained a few stings himself. Luckily the wasps went for the video camera instead!

Waiter There's a Wasp in my Fig!

A couple weeks ago we had the second round of our North Campus insect survey. Fifteen Museum staff tromped around the North Campus to see what insectuous wonders we could collect. Although we found some notably large specimens, the largest being a 3-inch bird grasshopper (Schistocerca sp.), the most interesting find was actually something a lot smaller. Much, much smaller in fact: a minute fig wasp about 2 millimeters in length!

Female Fig Wasp, Pleistodontes sp.

Fig wasps belong to the wasp family Agaonidae and as their name implies, they have a life history intricately linked with fig trees, family Moraceae. In fact fig trees can not produce figs without the wasps, and the wasps can't reproduce without the figs! The way this mutually beneficial relationship works is quite astonishing, especially if you take a journey to the core of a ripening fig!

Journey to the Center of the Fig

It all starts when a mature female fig wasp enters the synconium (an immature fig if you will) through its natural opening, called the ostiole. This sounds really easy when you think how small these wasps are, but nature has not made it easy on the fig wasp, as the opening is actually too small for the adult wasp to enter without damaging herself. It's so small that the fig wasp often loses her wings and much of her antennae as she struggles through the opening. To enable passage through the ostiole, the underside of her head is also equipped with spines that help to get a grip as she's going through the hole (see image above).

Once inside the synconium she passes over the fig's female flowers and inadvertently deposits pollen from the male flowers of her original host tree. She then deposits her eggs in the cavity. Her business being done, she dies. The Pleistodontes fig wasp we found is, interestingly, not a pollinator of edible figs. Instead, it is a pollinator of ornamental figs which can be found in backyards and parks across Los Angeles.

Once pollinated, the fig fruit begins to develop, consuming the wasp's dead body in the process. The eggs hatch and the larvae consume small parts of the developing fig. After the larva eat enough fig, they pupate and finally emerge as adult male and female wasps. The wingless male wasps have only two functions to perform in their short lives—to mate and to escape! Finding a mate inside the fig isn't too difficult for the male wasp as all of his sisters are stuck inside the fig with him (remember how small the ostiole opening is). After he mates with at least one of his siblings (or offspring from another wasp), he begins digging a tunnel to exit the fig. This tunnel is the escape route that the female wasp uses to exit the fig, but not before she picks up pollen from the male flowers. This pollen will eventually pollinate the developing fig she visits to lay her own eggs in, and thus the life cycles of both fig and fig wasp continue. 

All I can say is WOW! Nature is weird, wonderful, and so cool!

Thanks to entomology curator Brian Brown for identifying and photographing the wasp.

Bee Hotel California

Bee Hotels

We here at the Museum really like bees, so much so that we are building them a hotel! This hotel will contain over 200 deluxe suites for native bees. We've specifically designed the hotel to accomodate various solitary bees found in L.A. We'll keep you posted as we see what moves in. Thanks to exhibit fabricator, Jerome Brown, the hotels are nearly ready to be put out in the Butterfly Pavilion yard.

Cedar log with pre-drilled bee holes

Swarm!

It seems that other bees have heard how luxurious our accomodations are and stopped by to check them out! Last Friday we got reports of a European honey bee, Apis mellifera, mass in one of the Magnolia trees on the west side of the Museum. Brent "the Bug Guy" Karner, went to check it out and took this picture below, thanks Brent!

Honey bees, Apis mellifera

This mass of bees is called a swarm and likely contains over 1,000 bees! Swarming is a natural part of a honey bee colony lifecycle and provides the colony with a means of reproducing. This is the season for seeing swarms, as colonies have increased in size and no longer comfortably fit in their nests. In preparation for this big move, the old queen lays eggs that will turn into new queens and she takes off with about half of the colony to find new a new home. If you come across a honey bee swarm, don't worry, since they are all adults with no nest to defend, they are not quick to sting.