Finding the flora and fauna: Butterfly Center staff conduct a BioBlitz in Memorial Park

Editor’s Note: The term “BioBlitz” was first coined in 1996 for intense attempts to record all the flora and fauna within a designated area. National Geographic, which has partnered with parks around the country for various BioBlitzes, describes them as “a 24-hour event in which teams of volunteer scientists, families, students, teachers, and other community members work together to find and identify as many species of plants, animals, microbes, fungi, and other organisms as possible within a designated area.”  These quick and dirty surveys are used both to gather information about the biodiversity of a given area, and since members of the public and other non-experts (students, etc.) are often included as participants, as ways of sparking public interest in local flora and fauna.

The “Eco-Tech” panel of the Memorial Park Conservancy recently recruited the Butterfly Center to conduct a preliminary survey or “mini-BioBlitz” of the insect fauna throughout Memorial Park, with the idea of inviting members of the public to help on future surveys. One of the goals of the panel is to get some baseline data on the biodiversity of all the creatures that live in Memorial Park, and from there, make plans on how best to preserve and manage or enhance this wildlife.

We were asked to survey several different natural habitats in Memorial Park (i.e., not the golf course). On a sunny morning in early July, Butterfly Center staff members, our summer intern, and a couple of volunteers drove out to Memorial Park armed with insect nets and containers.  While some surveys (such as birds or trees) can be done without collecting, there are so many kinds of insects (and so few experts) that at least some specimens have to be collected in order to make identifications.  

We decided to sample 10 transects — 100 feet long by about 8 feet wide — each one in a different area. Our first couple of sites were in open prairie vegetation, so we used sweep nets and aerial nets to collect samples. In case you are not versed in insect collection techniques, a “sweep net” is a canvas net bag on a sturdy metal frame that is swished through the vegetation. Periodically, the contents are emptied into Ziploc bags or other containers. 

This giant fishing or nursery web spider was nearly three inches across! (photo by Zac Stayton)

This giant fishing or nursery web spider was nearly three inches across! (Photo by Zac Stayton)

 

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We found lots of these small millipedes (and a few slugs) in the leaf litter in the forested areas. (Photo by Zac Stayton)

Aerial nets are the more familiar “butterfly nets”: a much lighter, more delicate net bag that is swung through the air (it should NOT be dragged on the ground, used in water, or swiped through bushes!). These nets are more for catching fairly large, individual insects, especially ones that fly, so samples are put directly into a glassine envelope, or vial, or other appropriate container (or, if it is something readily identifiable, simply noted and released). Sweep nets generally collect things like grasshoppers and katydids, walkingsticks, mantids, leaf hoppers, stink bugs, the odd caterpillar, spiders, etc. Aerial nets are useful for larger flying insects such as butterflies, dragonflies and damselflies, wasps, bees, some beetles, certain flies, etc. 

In the more forested areas, sweep nets were not really appropriate, so we used the aerial nets and also took litter samples (scraping up leaf litter and bagging it). Litter samples are typically brought back to the lab to process in a so-called Berlese funnel. Many small arthropods who live in the litter of the forest floor, including springtails and cockroaches, ants, small beetles, millipedes, etc., can be collected in this way.

 Another find in the leaf litter:  a “woolly bear” caterpillar.  This is the larval form of the Giant Leopard moth, Ecpantheria scribonia.  The caterpillar rolls up in a ball, showing red stripes between segments covered with black “fur” (these caterpillars do not sting but probably taste bad so are warningly colored).  (photo by Nancy Greig)


A find in the leaf litter: a “woolly bear” caterpillar. This is the larval form of the giant leopard moth, Ecpantheria scribonia. The caterpillar rolls up in a ball, showing red stripes between segments covered with black “fur” (these caterpillars do not sting but probably taste bad so are warningly colored). (Photo by Nancy Greig)

There are many other collection techniques, none of which we used in this preliminary survey. Pitfall traps are always fun; they are empty cans or jars set into the ground with their mouths at ground level. Sometimes bait (a little raw chicken or fish, for example) is put in the bottom.

Crawling insects, especially those interested in odorous food, fall into the “pits” and cannot get out. Such traps need to be checked every couple of days — often they will contain different kinds of beetle, maybe a cockroach or two, etc.

Malaise traps are screen tents or baffles that trap small flying insects. The insects get caught in the folds of the screen and since they typically crawl upwards to escape, can be funneled into a container filled with alcohol.

Yellow pans are any wide, shallow container with a yellow (painted or otherwise) bottom.  These are partly filled with water and a bit of liquid detergent. Wasps and pollinating flies, etc., are attracted to the yellow color and cannot escape once they fall into the soapy water. Yellow pans need to be used in open areas in sunny weather and the samples removed every day or two.

Our final survey site was along the banks of Buffalo Bayou, which was much higher than usual so there was not much shore. Here, we mostly used aerial nets. We saw several things in this area that were not seen other places, especially tiger beetles, damselflies, etc. Here, we mostly used aerial nets (or grabbed things with our hands). 

The gorgeous Ebony Jewelwing a common damselfly species along the banks of Buffalo Bayou in Memorial Park

The gorgeous Ebony Jewelwing, a common damselfly species along the banks of Buffalo Bayou in Memorial Park.

 

The vibrantly colored Vivid Dancer is a common damselfly species along the banks of Buffalo Bayou in Memorial Park

The vibrantly colored Vivid Dancer is a common damselfly species along the banks of Buffalo Bayou in Memorial Park.

By noon, it was blazing hot and we were all soaked in sweat, so we bagged things up and stopped at the Shandy Café (great little place on Memorial Drive) for lunch on our way back to the Museum. 

Although we only collected for about three hours, we have our hands full in identifying everything. We first have to sort things to order, identify what we can, and then we will probably have to send some things off to experts in the various insect groups. I’m sure it will take us several weeks! 

Some of the coolest things we found: 

It’s always fun to open up the sweep net and find walkingsticks or praying mantids, or a colorful leafhopper. We picked up quite a few different grasshoppers and a few katydids.  We noted but did not catch too many butterflies (we can identify most of these by sight, so no need to collect).

I like wasps and bees; we saw several of the large red Polistes wasps, carpenter bees, leaf cutter bees, and a really cool “digger” bee starting her nest tunnel in the sand (see attached video clip). A medium-sized beetle that looked like a wasp was visiting flowers in several places. 

The very fast tiger beetles mostly eluded us down at the bayou’s edge, but we did catch a few damselflies there. The most common one there was the lovely Ebony Jewelwing.

Tiger beetles are extremely fast moving, long legged, predatory beetles that often occur in open sandy areas, especially along streams.  We saw many of these, probably Megacephala virginica – and managed to catch a few – along the bayou.  (photo from BugGuide.net by Chris Wirth)

Tiger beetles are extremely fast moving, long-legged, predatory beetles that often occur in open sandy areas, especially along streams. We saw many of these, probably Megacephala virginica – and managed to catch a few – along the bayou. (Photo from BugGuide.net by Chris Wirth)

 

Hibiscus bee, Ptilothrix bombiformis

Click here to watch a video of a female Hibiscus bee, Ptilothrix bombiformis, a solitary species as she digs a nesting tunnel into hard-packed earth as we found on our BioBlitz.

Once we have compiled our results and reported them to the EcoTech Panel, they will then make plans for another survey sometime in the fall. I believe they intend to invite more general participation, so if you are interested in the insects of our area, keep your ears open!

STEM & GEMS: Insects and plants fascinate “bug nerd” Lauren Williamson

lauren photo in CBCEditor’s Note: As part of our annual GEMS (Girls Exploring Math and Science) program we conduct interviews with women who have pursued careers in science, technology, engineering, or math. This week, we’re featuring Lauren Williamson, Entomologist in the Cockrell Butterfly Center

HMNS: How old were you when you first became interested in science?
Williamson: Ever since I can remember! I was always catching bugs, playing with animals, and looking at flowers, plants, etc.

HMNS: Was there a specific person or event that inspired you when you were younger?
Williamson: I had a biology teacher in junior high that told me about entomology and told me that I should look into that field for a career since I had such an interest in insects.

HMNS: What was your favorite science project when you were in school?
Williamson: An insect collection, of course!

HMNS: What is your current job? How does this relate to science, technology, engineering, or math?
Williamson: My title is “entomologist”, aka “bug nerd.” My job revolves around importing exotic butterflies to display in our Butterfly Center. Not only do I need to know a lot about insects, but I also need to know about government regulations, computer applications, and accounting. We also do a lot of outreach programs, so it’s a necessity to be comfortable presenting to large groups.

To get a degree in entomology you have to take extensive coursework in biology, chemistry, physiology, and math.

HMNS: What’s the best part of your job?
Williamson: I play with butterflies all day — need I say more? Not to say that my job doesn’t involve a lot of hard work, because it does, but the fun parts of my job make it all worth it!

HMNS: What do you like to do in your spare time?
Williamson: I love to play with my animals (three dogs: Merle, Hank, and Molly; and a bird: Carlos), go on insect collecting trips, camping, crafts, going to museums and seeing movies with my husband.

HMNS: What advice would you give to girls interested in pursuing a STEM career?
Williamson:
Make sure you study, study, study! Ask a lot of questions and learn all of the material as much as possible. Every year adds more information to the knowledge base you already have, so it only gets harder.

HMNS: Why do you think it’s important for girls to have access to an event like GEMS?
Williamson: This is a great way to experience some of the wonderful career paths you can take with a firm knowledge of science, engineering, technology, and math. These subjects are the foundation of our everyday lives, whether you realize it or not! There will always be a demand for employees in these ever-growing and changing fields so it is important to get in an interest in them as soon as possible.

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Tales from Tanzania: That’s no mint on your pillow

Some hotels leave mints on pillows. But in the African Serengeti, you get assassin bugs.

Assassin bug on a pillow

Not a mint.

Dave and I had been actively searching for invertebrates on our trip to no avail. The guides thought we were weird (crazy) from all of our questions about insects (as well as snakes and lizards). No one goes to Tanzania for the little things — they’re only interested in the big stuff.

So imagine our delight when we came “home” one night and discovered this AWESOME assassin bug on our pillows.

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David, with our non-mint, and our pillow.

Assassin bugs are awesome because they have specially adapted mouths, perfect for sucking “the goodie” out of other insects. They pierce through the exoskeleton of their prey and inject saliva into the body. The saliva liquefies the innards of the prey, which can then be sucked right out (like a smoothie!).

An assassin bug with its prey.

Not only are assassin bugs insect-smoothie-enthusiasts, but they’re great at defending themselves. They can spit their saliva into the eyes of those things that might try to eat it (birds) or accidentally disturb it (humans), causing temporary blindness.

Now tell me that’s not awesome.

The life cycle of an assassin bug

DISCLAIMER: We may have totally lied to everyone on the trip — and by, “We may have lied,” I mean, “We totally lied.” Knowing what the assassin bug can do, we decided to tell our fellow travelers that we found it outside our room rather than on the pillow. Why cause a panic? (But don’t tell the others.)

Kwa heri!

Color me Carmine: Cochineal bugs in our food and drink

At the liquor store the other day I noticed a bottle of shocking pink tequila, called “Pasión.” It would make a great Valentine’s Day gift (“Candy’s dandy, but liquor’s quicker,” as the saying goes) and is certainly eye-catching. More interesting, I learned that the pink color came from cochineal bugs – as stated right up front on the label!

Most people don’t know about cochineal bugs or the widespread use of colorant that’s extracted from them, but cochineal, or carmine, has been valued for centuries as a red dye. One of the few natural and water-soluble dyes that resists degradation with time, cochineal is the most light-stable, heat-stable and oxidation-resistant of all the natural colorants and is even more stable than some synthetic dyes. Moreover, depending on the process used, it yields a range of vibrant colors, from light oranges and pinks to deep crimson.

Bugs in your booze? You'd better believe it!

Cochineal, close up

Unfortunately, when you inform people that their raspberry yogurt, maraschino cherries, Starbucks Strawberry Frappuccino, brand of lipstick, or hundreds of other items are colored with this natural extract, most are revolted instead of intrigued. In fact, outraged vegans have pressured Starbucks to look for another, non-insect-derived product to use in the frappuccino concoction (just do a web search for “cochineal and Starbucks”).

So what IS a cochineal bug, exactly?  It is a small, chubby scale insect that feeds on prickly pear cactus, with the scientific name of Dasylopius coccus. There are many species of scale insect. Most are very small (i.e., less than ¼ inch long, some smaller), sedentary insects that suck plant sap with tiny, piercing mouth parts. They belong to the same order of insect that includes aphids, cicadas, and leaf hoppers: the Homoptera.

However, you might not even recognize some scale species as insects. Adult females have no legs or wings and are basically bags of guts and eggs that seem glued to the stems or leaves of their host plant (the smaller, winged males are seldom seen). Some scales have hard, shell-like coverings, and indeed look like tiny shells. Mostly considered plant pests, a few have economic value. For example, shellac is another natural product derived from a different scale insect.

Bugs in your booze? You'd better believe it!

Cochineal as they appear feeding on prickly pear cactus

Cochineal bugs are covered with a waxy or powdery white coating, and often cluster on the surface of the prickly pear pads, looking like tiny cotton balls stuck to the plant. But if you squish these cottony balls, your fingers will be covered with copious amounts of a thick, dark red fluid. This intense color has been used to dye fabric for many centuries, and more recently, has become an important colorant in foods and drinks.

Cochineal bugs are native to Central and South America, where their host plants, the cacti, also originated. Both Incas and Aztecs used cochineal as a dye, which was so highly prized that bags of the dried bugs were used as currency or as tribute. The Spaniards took cochineal back to Spain, and during colonial times, cochineal was Mexico’s second-most valuable export after silver. Cochineal was much superior to the red dye used in Europe at that time, and became hugely popular. It was used to dye the cloaks of Roman Catholic cardinals and the “redcoats” used by the British army.

Bugs in your booze? You'd better believe it!

Cochineal-dyed yarn

In the mid 1800s, with the advent of chemical dyes, which were cheaper to produce, the demand for cochineal in the fabric industry waned and the industry all but collapsed. But in the late 1900s, the push to use natural products rather than chemical ones in foods have made cochineal and carmine, its purified form, increasingly important as food colorants.  Today cochineal is again produced on a commercial scale.

To quickly summarize the production process: cochineal bugs are allowed to grow on prickly pear pads for about three months. They are then scraped off the pads and thoroughly dried (often sun-dried) for several days. The resulting seed-like pellets are ground and mixed with water to produce cochineal, or are further refined to produce carmine or carminic acid. It takes about 70,000 bugs to make one pound of cochineal extract.

Bugs in your booze? You'd better believe it!

Dried, harvested cochineal

Today most cochineal comes from Peru, the Canary Islands, and Mexico. Check out this YouTube video to see traditional cochineal farming in the Canary Islands. You might also be interested in this great video from the North Carolina Museum of Natural Science about cochineal in foods.

If you’d like to learn more, just do an online search for “cochineal bugs” (by the way, they have occasionally been misnamed “cochineal beetles” – but they are NOT beetles). For those of you who prefer old-fashioned reading, Amy Greenfield has written an entire book about the fascinating history of cochineal titled A Perfect Red.

Bugs in your booze? You'd better believe it!

Cochineal harvesting in colonial Peru

I have to roll my eyes a little (at least internally) at those people who act horrified when they learn that the red color of their energy drink, or popsicles, or other foods comes from or is enhanced by these insects. In fact, we eat insects all the time. There are government-approved amounts of insects allowed in almost all foodstuffs (also other, ickier stuff such as rat feces, animal hair, and dirt). That chocolate bar, slice of bread, bowl of cornflakes, serving of pasta, dollop of ketchup – all are likely to have bits of insects in them.

I encourage you to visit the exhibit on this theme in our entomology hall, where you can also purchase some unadulterated insect treats from our vending machine. Did you know that the average American eats – unknowingly – one to two pounds of insects per year? But not to worry, insects contain lots of protein and are good for you!

A very few peop