Thursday, February 24, 2011

Killer wasps are coming! (to the 28th annual Insect Fear Film Festival)

Killer wasps are coming! (to the 28th annual Insect Fear Film Festival)

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In anticipation of the 28th Annual Insect Fear Film Festival, which they will host Saturday on the U of I campus, this week’s Environmental Almanac is written and narrated by four members of the Entomology Graduate Student Association: Michelle Duennes, Rob Mitchell, Laura Steele and Katherine Noble.

[Katherine] This year's festival, Killer Wasps, plays on our almost primal fears of these stinging insects. However, the majority of wasps can't sting people, and actually don't care much about us at all. Most wasps are parasitoids, which means their larvae live inside other insects. Many others are herbivores and feed on plant material. Only a small subset of social wasps have evolved to be the stinging predators with which we're most familiar. [The wasp pictured here, Isodontia mexicana, is native to Illinois. It may look fierce, but its sharp ovipositor is used to lay eggs in the larvae of other insects, not to sting people. Photo by Alex Wild, http://www.alexanderwild.com/]

[Rob M.] The first wasps were almost certainly herbivores that fed on leaves or inside the wood of trees. Many of these species are still around today, and you might know them as sawflies or wood wasps. They appear quite different from other wasps: the larvae look almost exactly like caterpillars, and the adults lack the characteristic "wasp waist." Though most are small and unremarkable, a local species called the horntail can reach lengths of up to an inch and half. Horntails are so named from the stiff, powerful spine extending from their abdomen called an ovipositor, which they use to chisel into wood and lay eggs. Even if you have never seen a horntail, you may come across its horn embedded in a tree after the luckless insect was snatched by a bird while laying eggs.

[Laura] The majority of wasps are parasites or parasitoids. Parasites exploit a host for reproduction or development purposes without killing the it, while parasitoids ultimately kill the organism that hosts their larval development.

The unlucky insect host of a parasitoid often remains alive, either paralyzed or unable to remove the invading larva, while it is essentially eaten from the inside. While this may be a living nightmare for the host insect, it can be a miracle for farmers, who often use parasitoids to help control insect pests of crops.

The smallest known insect, the fairy fly, is actually a tiny parasitoid wasp that has a wingspan of about 3 millimeters or less. On the other extreme is the large Cicada Killer wasp, which can be one-and-a-half inches in length. Here in Illinois, you are likely to see one of these wasps dragging a paralyzed cicada into its underground burrow where it will then lay an egg on the immobile insect.

[Michelle] At some point, most of us have been stung by some sort of wasp or bee. Stingers are modified ovipositors, which means that only female bees and wasps are capable of stinging. Like bees, some wasps possess a form of sociality, which is when individuals of the same species live together, share resources and divide labor and reproduction among the individuals in the group. Unlike the honey bee, wasp colonies can have multiple egg-laying females, called gynes.

The social wasps include the insects most people know as hornets, yellowjackets, and paper wasps. One of the more infamous stinging wasps is the velvet ant or cow killer. Its sting is incredibly painful, but it can’t actually kill cows.

The Insect Fear Film Festival will take place at the Foellinger Auditorium on the UI campus, with festivities beginning at 6:00 p.m. and films beginning at 7:00. Further details are available at www.life.illinois.edu/entomology/egsa/ifff.html.

Thursday, February 17, 2011

Waning of winter brings change, opportunities for engaging the natural world

Waning of winter brings change, opportunities for engaging the natural world

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Last week, we had low temperatures below zero; today, a high in he 60s. Here we are in February.

You might scarcely believe it, but great horned owls in our area are already sitting on eggs. This timing enables their young, which will hatch later this month or early in March, to fledge when the young of mammals they prey on become abundant, and it gives them extra time to mature before next winter. [Photos by author.] Within the next couple of weeks some of our early bird migrants will also be returning. Keep an eye on places where cattails grow for the year’s first red-winged blackbirds, the true harbingers of Spring in east central Illinois.

Birders who are itching for activity have some good opportunities this month. The Great Backyard Bird Count, sponsored by the Cornell Lab of Ornithology and the National Audubon Society, runs from February 18th through the 21st. This event encourages people to record their observations of birds over the three-day period according to a simple set of guidelines, and then submit them via the Web.

You can participate in the Great Backyard Bird Count at home or in the company of other people. The Champaign County Audubon Society will be counting birds at the Anita Purves Nature Center in Urbana on Saturday, February 19th, from 9:00 a.m. until 4:00 p.m.

If you’re feeling more adventurous, you might also be interested in an “Owl Prowl,” an evening program led by educators with the Champaign County Forest Preserve District that includes a chance to see wild owls. One is taking place this evening at Lake of the Woods in Mahomet, but at this point you might have better luck with the one set for next Thursday, February 24, at Homer Lake.

Absent truly unusual weather, the next four weeks will see the ice that still covers our ponds and wetlands retreat. As it does, amphibians will congregate to breed—more salamanders, toads and frogs than you would ever imagine if you’ve not gone out on a rainy March night to see and hear for yourself.

People who are interested in such creatures can participate in an ongoing local effort to conserve them, the frog call monitoring program conducted cooperatively by the Champaign County Forest Preserve District and the Urbana Park District. After completing required training, volunteer frog call monitors keep records of which frogs they hear at assigned sites between the beginning of March and the end of July. They then submit their observations to the sponsoring agencies, which use the collected information to make decisions about how sites are managed. The two required training dates for frog call monitoring are March 8th and March 15th, with registration open until February 25.

Whether or not the current thaw continues, the first flower of spring, skunk cabbage, will emerge in woodland seeps by the end of the month, thanks to its capacity to generate heat and grow through frozen soil. Few people will go out of their way to see it, but doesn’t it do you good just to know that something will be growing soon?

If you’re dreaming up plans for your own garden this year, check out the one–evening program, “Eco-conscious Gardening and Landscaping,” that will be offered at the Champaign County Extension auditorium on Monday, February 21st. There, local experts will share advice on how people can help prevent ecological problems and promote biodiversity by the choices they make in designing home landscapes.


Great Backyard Bird Count

www.birdsource.org/gbbc/

www.champaigncountyaudubon.org/calendar.htm
CCFPD Owl Prowls
www.ccfpd.org/Calendar.html
Frog Call Survey Training
www.ccfpd.org/NaturalResources/FrogCallSurvey.html
Eco-conscious Gardening and Landscaping
http://web.extension.illinois.edu/champaign/

Thursday, February 10, 2011

Returning a bit of prairie to the Prairie State

Returning a bit of prairie to the Prairie State

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A week ago last Friday morning, I joined up with a group of eight other people to sow seed. Not in a greenhouse. Not in a dream. We were planting prairie at the Loda Cemetery Prairie Nature Preserve just 30 miles north of Champaign in Iroquois County.

The focal point of the Loda preserve is a 3-acre parcel of land adjoining Pine Ridge Cemetery, which was preserved from plowing or grazing since the time of European settlement in anticipation of burials there. When this parcel was recognized as one of the very few intact remnants of tallgrass prairie in Illinois in the 1980s, it was purchased by the Nature Conservancy and dedicated as an Illinois Nature Preserve. Since 1983, the preserve has been maintained by the Urbana-based conservation group, Grand Prairie Friends, which took ownership of it in 2004.

Of course, the intact prairie at the preserve, which includes an astonishing diversity of plant life, more than 130 species in all, does not require seeding. We were planting an expansion of the prairie. This land, which was bought by Grand Prairie Friends in 2007, surrounds the prairie remnant on three sides and includes an area of 9 acres.

According to Mary Kay Solecki, who is a field representative for the Illinois Nature Preserves Commission, the expansion is crucial to the long-term health of the preserve. In her words, “We’ve come to understand that these tiny prairie remnants are subject to a lot of stress because they are so small. The things that degrade them, especially invasive plants and animals and herbicide drift, are worst at the edges, and there’s little that’s not “edge” on a one or two or three-acre site.”

Solecki continued, “It’s very fortunate that the local steward at Loda was able to communicate this to the owner of the surrounding property, and that he was willing to sell some land to help alleviate the problem.”

The seeding that I helped with, and all work on the Loda expansion, adheres to a formal plan, the goal of which is to maintain the unique character of the remnant prairie by replicating it as nearly as possible in the expansion.

So the seed we scattered came not from a nursery or a mail-order company, but right from local plants, gathered especially for the purpose in the heat of last year’s summer by an assortment of scientists and enthusiastic volunteers. In the mix were big bluestem and other tall grasses from the Loda remnant itself; pale purple coneflower from the Prospect Cemetery Nature Preserve, just up the road; compass plant from the Short Line Railroad prairie near Gifford, and the seed thirty-some other flowering plants.

The process of planting was every bit as enjoyable as you might expect. We began by using our hands to combine the seeds of all the plants in a large plastic bin. Then, carrying it in buckets or bags, we simply walked the area and scattered it. A thin layer of snow covered the ground, and the air temperature was just warm enough to soften the top of it, so the seed sank in slightly rather than blowing around. To further ensure that it stayed in place, a tractor pulled a roller over the ground as we finished.

Unlike the seeds of crops and annual garden flowers, the seeds of native prairie plants benefit from exposure to winter, so the timing of our planting in advance of last week’s storm was just right. If all else goes well, there will be a little bit more prairie in the Prairie State come Spring.

Thursday, February 03, 2011

U.S. and Canada took a step toward healthier waters in 2010--did you notice?

U.S. and Canada took a step toward healthier waters in 2010--did you notice?

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Last summer, something good happened for the waters of the United States. You can be excused for not having noticed, since this small step forward took place at the same time the Deepwater Horizon was spewing oil into the Gulf of Mexico. The major manufacturers of automatic dishwasher detergents started selling only products that are nearly phosphate-free.

The elimination of phosphates from dishwasher detergents brought them into line with other household products, such as laundry detergent, that have been required to work without phosphates for years.

The big manufacturers made the change in grudging response to strict limits on phosphates in dishwasher detergents enacted simultaneously by sixteen states, including Illinois. The choice faced by the manufacturers was whether to maintain different product lines for different states, or just meet the higher standard across the board.

While the switch to phosphate-free dishwasher detergents occurred without most people noticing (and plenty of people have been consciously choosing phosphate-free dishwashing products for years), others, especially people with hard water, have had trouble adjusting.

In fact, I learned of this story by way of an uncharacteristically bad report on National Public Radio, which focused on the complaints of two people whose dishes weren’t coming out at clean as they used to. This story neglected entirely the benefit to our waterways of reducing phosphorus pollution. It even included without comment the absurd statement from a woman in Texas who said, “I'm angry at the people who decided that phosphate was growing algae. I'm not sure that I believe that.” (If you're among people still looking for a no-phosphate solution, the September 2010 issue of Consumer Reports provides good options.)

For the record, Mark David, a professor in the UI Department of Natural Resources and Environmental Sciences who specializes in nutrient cycling, explained for me the effects of phosphorus pollution: “Phosphorus is usually the limiting nutrient for the growth of algae in streams and lakes. Even at low concentrations, it can lead to large amounts of algal growth, which can reduce the amount of dissolved oxygen in water and harm aquatic organisms, including fish.”

If you’ve ever looked down from a bridge and observed long strings of plants waving in the current of a stream, or seen a pond that’s bright green, you’ve seen the effects of excess phosphorus in fresh water.

David acknowledges a fact that the big manufacturers of dishwasher detergent like to point out, which is that removing phosphates from their products will not by itself solve the problem of phosphorus pollution. That’s because most phosphorus in streams and rivers comes from agricultural fields and what people eat, with the phosphorus entering the environment in sewage effluent. But, he says, removing phosphates from dishwasher detergents is a step in the right direction, especially when you consider that sewage treatment facilities are likely to face restrictions on how much phosphorus they discharge in the future.

In Spokane County, Washington, which enacted its own tight restrictions on phosphates in dishwasher detergent in 2009, a year’s worth of data showed that water entering the sewage treatment plant contained 10.7 percent less phosphorus than it had on average in the preceding three years.

Ultimately, much of the phosphorus pollution that enters streams in Illinois reaches the Gulf of Mexico, where it contributes to the creation of the dead zone. So while the Deepwater Horizon has been capped, this spill of nutrient pollution, which begins in the Midwest, continues. Ultimately, it will have to stop here.