Thursday, July 29, 2010

Getting the scoop on Illinois mussels

Getting the scoop on Illinois mussels

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The freshwater mussels that inhabit the streams of Illinois spend most of their lives buried in the substrate, exposing only the parts they use to take in and expel a steady flow of water, from which they filter their food. This mode of living poses certain challenges for the scientists whose work it is to monitor mussel populations. As Illinois Natural History Survey (INHS) field biologist Alison Price explained to me, it is sometimes possible to sample for mussels visually, but only in waters that are shallow and clear enough to afford a good view of the streambed—a rare case in the Prairie State. More often, she and her colleagues sample for mussels by “grubbing.” “It is what it sounds like,” she quipped. “You reach down and rake your fingers through the sand and gravel until you feel a shell.” [Photo: Price grubbing for mussels in the Mackinaw.]

Recently, I spent some time in the field with Price and her colleagues, to learn about their work and even do a little grubbing myself.

Our day began at a site on the Mackinaw River northeast of Bloomington, with a “maximum effort survey,” which was performed in part to collect data for a UI graduate student who is studying the efficiency of current sampling methods. In conducting this survey, members of a crew that included biologists and technicians from both the Natural History Survey and the Illinois Department of Natural Resources collected all of the mussels they could find from a predetermined stretch of river in a set amount of time. Then, without returning any of the mussels previously collected, they covered the same territory again three more times.

What they turned up was amazing to me, although about what they expected. One-hundred-fifty-one live mussels were collected, with representatives from 10 different species, most numerous among them fatmuckets, plain pocketbooks and round pigtoes (and which, I admit, I list here just because I find the colorful common names of mussels enjoyable). After these were all sorted and measured they were returned to the river, where, presumably, they hunkered right back into the substrate and resumed filtering the water for food.

By analyzing data collected through this and other “maximum effort” surveys, the UI student is seeking to answer the question of whether current sampling protocols provide information that is reliable enough to accurately assess populations of rare mussel species. The question arises since rare species are more likely to be missed altogether or underrepresented using current techniques.[Photo: UI graduate student Jain Huang and INHS field biologist Diane Shasteen sorting mussels collected from the Mackinaw.]

More importantly, data from the Mackinaw River survey I observed will be combined with data gathered by Price and others at approximately 800 sites around the state as part of a three-year project. This project will ultimately provide state agencies with the information needed to manage and protect populations of mussels, which are among the most endangered groups of animals that occur in Illinois.

My day in the field with Price and her crew also included a second stop, to rescue mussels from a drainage ditch beneath a county road bridge that is slated for demolition. This effort was mandated by the known presence there of slippershell mussels, which are listed as threatened in the state. Our inelegant, yet highly effective method of finding mussels for removal there was to form a shoulder-to-shoulder line across the stream and crawl through the target area, grubbing as we went.

From this small stretch of unpromising looking stream, we retrieved 359 live mussels, including 11 slippershells. All of these were moved to reaches of the stream that would not be affected by the bridge work.

Illinois has already lost 20 of the 80 species of mussels that once occurred here, and our streams have become poorer as a result. Wouldn’t it be a great accomplishment if we could use the knowledge generated by today’s scientists to prevent further declines?

To learn more about mussels on the Web, you might want to start with the following:

Freshwater Mollusk Conservation Society

Illinois Natural History Survey Mussels:

Thursday, July 15, 2010

Effective wastewater treatment benefits wildlife, human health

Effective wastewater treatment benefits wildlife, human health

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In recent years my morning run has often included a pause to observe the wildlife of the Copper Slough, where it runs under Rising Road in southwest Champaign. Great blue herons and mallards are regulars there, as is a pair of belted kingfishers, which nest in the bank nearby and noisily patrol the stream corridor. In the pool below the bridge live masses of some fish that tolerate fairly degraded waters, especially common carp and suckers. But there are fish with higher standards there, too, among them some decent sized largemouth bass, as well as an occasional snapping turtle.

What makes the variety of life at this site remarkable is that less than a hundred feet upstream from my vantage point, the Urbana-Champaign Sanitary District’s southwest treatment plant, which serves roughly 40,000 people, discharges some 6 million gallons per day of treated wastewater into the stream. [Photo: Discharge from the UCSD plant entering the Copper Slough from the left, just upstream from where Rising Road crosses the stream.]

I recently had the opportunity see for myself what happens to wastewater at the plant that renders the effluent capable of supporting life, thanks to a tour with Mike Guthrie. In his current life, Guthrie is an East Central Illinois Master Naturalist, but before his retirement in 2006 he had been supervisor of operations for the Sanitary District.

Guthrie emphasized that contrary to whate many people expect, most of the processes that take place at the plant do not rely on chemicals. Rather, they replicate processes that occur in nature, only they are managed to occur very efficiently.

In the first stage of wastewater treatment re the sewage that comes into the plant is screened to remove paper. This process takes place inside a building, the only place on the tour where we really had to hold our noses. The material removed in this process is the only byproduct of the plant that goes to a landfill, and the quantity of that is surprisingly small, on the order of one dumpster a week.

In the next stage of treatment, wastewater is channeled through a series of open-air basins where bacteria and other microorganisms are introduced to remove phosphorous and other pollutants. [Photo: Secondary treatment basins, left, and clarifiers, right, seen from the top of the nitrification tower.]

From this secondary treatment, water flows into clarifying tanks where the microorganisms introduced before settle out, to be cycled back into the previous process. From this point the water is pumped to the top of nitrification towers, the tallest structures at the plant. Here it is sprayed over stacked layers of honeycomb-like plastic that fill the inside of the tower. As it runs down through them, another group of microorganisms converts toxic ammonia into nontoxic nitrates.

After passing through a filter that removes any solids that might have been introduced in the nitrification process, the water from the Southwest Plant is released into the Copper Slough.

We have effective federal law—the Clean Water Act—to thank for the current high standard of wastewater treatment in the United States. And when I spoke with Glynnis Collins, executive director of Champaign-based Prairie Rivers Network, which seeks to ensure the consistent application of that law in Illinois, she shared my enthusiasm about how far we’ve come in the past 50 years.

But Collins also noted there is still work to be done. She pointed out, for example, that the Illinois EPA, which administers permits for discharge into streams, sometimes exempts wastewater plants from the final step of disinfection, making them unsuitable for human contact for some distance downstream. In addition, she explained, we’re still just beginning to understand how pollutants that are not treated by current systems, especially some of the human medications that are showing up in water all over the world, impact people and wildlife.

Thursday, July 08, 2010

Volunteers key in effort to restore endangered Illinois orchid

Volunteers key in effort to restore endangered Illinois orchid

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Among the more than 130 species of native plants that make up the flora of the Loda Cemetery Prairie Nature Preserve in Iroquois County, the eastern prairie fringed orchid (Platanthera leucophaea) can be difficult to pick out, and the beauty of its flowers is best appreciated up close. They’re only about an inch long, and they grow in a cluster on a single, upright stem. Each has a lower lip divided into three parts, which branch toward the tip like tiny antlers. From any distance, the prairie fringed orchid tends to be obscured from view by its taller neighbors.

What sets the prairie fringed orchid apart is its rarity. Prior to European settlement, it was widespread across the upper Midwest, with the largest and most extensive populations occurring in Illinois, where it was found in 33 counties. Loss of habitat due to agriculture and urban development has eliminated it from all but nine counties, and only three of those are outside the Chicago metropolitan area.

The fringed prairie orchid is currently listed as “threatened” federally and “endangered” in the state.

Because it is listed, the prairie fringed orchid is the subject of a recovery plan developed by the U.S. Fish and Wildlife Service. This plan, which was crafted and approved in the 1990s, involves a great deal of cooperation among scientists, landowners, and conservation organizations, and it relies heavily on the efforts of citizen-scientist volunteers.

At Loda Prairie Nature Preserve, which is owned and protected by the conservation group, Grand Prairie Friends, the role of citizen-scientist is filled by Jackie Roy, who came to it as an active participant in the East Central Illinois Master Naturalist program. Before spring of 2008, she had never heard of the prairie fringed orchid, but she answered the call for a volunteer monitor because lives just down the road in Paxton.

As a fringed prairie orchid monitor, Roy visits her site three or four times in June and early July, when the orchids are typically blooming. [Photos: above, close-up of eastern prairie fringed orchid flowers; left, Jackie Roy making notes on her observations at Loda in June.] While there, she locates as many orchids as she can, beginning where plants have been found in previous years. When she finds one, she marks its location, measures its height, counts its leaves and blossoms, and makes notes about its general condition--whether, for example, it has been browsed by deer, etc.

If Roy finds more than one prairie orchid in bloom at the same time, she takes the further step of transferring pollen between the flowers on one plant and another. Prairie orchid flowers that are cross pollinated produce more viable seed than those that are not, and among small populations, the odds of cross pollination occurring without human intervention are fairly slim. That’s because fringed prairie orchids are pollinated by only a few species of night flying hawkmoths, which simply may or may not find them at the right time.

Is there any reason to think the eastern prairie fringed orchid will come off the lists of threatened and endangered species in the years to come? That’s a question I put to Cathy Pollack, who is a biologist with the U.S. Fish and Wildlife Service and coordinator of the recovery effort. She expressed hope that it would. “We’ve got a great team of researchers, scientists and partners helping us,” she said, “and right now that’s about all I can ask for.”