OKAY, I'LL CONFESS: MY SCENTIFIC specialty is nuclear physics, but I would much rather trace the course of a quiet stream than find my way along a linear accelerator any day. And ecology, especially stream ecology, affords more opportunities for meaningful amateur research. Indeed, the techniques used are so straightforward and the results so immediate that you can easily craft wonderful scientific experiences for your whole family with just a little preparation. And you can forge ties with others, too--with the rise of the environmental movement, thousands of part-time naturalists have banded together into nearly 800 independent organizations that work to assess the health of our nation's watersheds. These associations can help you and your family jump into this rich and rewarding area of research. Some of these groups have just a few members and operate on a shoestring. Others have hundreds of participants and annual budgets of tens of thousands of dollars. Some limit their activities to physical and biological surveys: they record the temperature, rate of flow and clarity of the water, or they take a regular census of the seasonal inhabitants of a stream. Other groups have the equipment to measure dissolved oxygen and pH levels, check for fecal coliform bacteria and test for various pollutants. All these volunteers make important contributions to bettering the environment, albeit one stream at a time.

These organizations report their findings to local, state and federal agencies that have an interest in water quality. The Environmental Protection Agency encourages this burgeoning torrent of amateur talent with a number of free publications. The EPA also helps to produce an outstanding semiannual newsletter called The Volunteer Monitor. This periodical knits independent environmental groups into a nationwide community by providing detailed instructions, some that will enlighten even the most experienced field researcher. It's easy to get your feet wet: just check out the EPA's listings on the World Wide Web to find a watershed volunteer organization near you. As with any diverse ecosystem, streams afford many opportunities for amateur research. Personally, I love to investigate the little critters that cling to rocks and branches or bury themselves in the sediment. Studying the diversity of these easily visible "macroinvertebrates" provides an excellent way to judge the health of the stream, because pollution affects certain types more than others. For example, finding stone-fly nymphs (relatively sensitive creatures) inhabiting a brook in one of the Middle Atlantic states would signal that the level of pollution is probably not too severe. But the rules change from place to place. So you will need to learn from people working in your area which of the local organisms are most sensitive to pollution.

To examine such invertebrates, you may find that some of the methods used for standing bodies of water are helpful [see "The Pleasures of Exploring Ponds," The Amateur Scientist, September 1996]. But the rush of the relatively shallow water in streams makes the technique described here particularly well suited to collecting biological specimens.

To start, you'll need a good net. Affix a one-meter square of fine-mesh netting between a pair of strong supports. (Stout wooden dowels would work well.) Environmental groups in your area may use a standard-size mesh for such studies--500 microns is common--in which case you should do the same. Otherwise you can just use plastic window screening. Then go out and select three representative sites from a section of your stream that is no more than 100 meters long. Your aim is to sample a one-meter-square patch in each spot. To do so, you and a partner should put on rubber hip boots and wade in, approaching from downstream so that anything kicked up by your steps will not affect your investigation.

When you reach your first site, open the net, dig the ends of the dowels into the bottom so that the net tilts downstream at a 45-degree angle. Make sure the base of the net lies flush against the streambed. Have your helper step one meter in front of the net and pick up all the large rocks from the sampling area, gently rubbing them underwater to dislodge any organisms living on them. The flow of the stream will carry anything rubbed off into the net. (Alternatively, rubbing the rocks over a bucket may be a more direct way for you to collect these organisms.) Your partner should then stir up the bottom in the designated patch by kicking things around for a couple of minutes so that the organisms living between the smaller rocks are swept into the net. Finally, have your assistant grasp the bottom of the net and scoop it forward as both of you remove it from the stream and return to shore.

Use a magnifying glass to find and collect creatures from twigs and whatever other debris you've captured before you discard them back into the stream. Carefully dislodge the larger creatures from the mesh with tweezers; flush off the rest into a bucket with clean stream water. Let the contents of the pail settle and scoop out most of the excess water with a cup. Strain this water through a nylon stocking to make sure that nothing escapes. Then repeat this procedure at your other two survey sites, combining the specimens in your bucket.

Pour the water remaining in the bucket through your stocking strainers. Next, turn them inside out and use a little rubbing alcohol to wash the contents into an empty glass canning jar. Use a sugar scoop and tweezers to place the rest of the pail's living contents into the jar and fill it with alcohol to kill and preserve all these invertebrates before screwing on the top. Finally, place a large label on the jar and pencil onto it (alcohol causes ink to run) the location, date, time and the names of everyone on your crew. Later you can go through the collection and record the types and quantities of organisms present. Environmental groups working in your area can help you learn how to identify the sundry invertebrates. Or, at the very least, they should be able to point you in the right direction for gaining these skills. With this knowledge, you can revisit these same sites periodically to document environmental changes from season to season and, eventually, from year to year.

Although you'll probably want to gain some practice with streams close to your home, don't overlook the bigger picture. You can see how your stream fits into your regional river system by getting a 7.5-minute (scale 1:24,000) topographic map by the U.S. Geological Survey. You can purchase such maps at hiking supply stores or directly from the USGS. By checking with other groups and plotting the existing survey sites on your map, you'll quickly discover those places in need of study. Then grab your net, your bucket, your boots and a few family members and go to it.

For more information about this and other projects for amateurs, visit the Forum section of the Society for Amateur Scientists on the World Wide Web. You may also write the Society for Amateur Scientists, 5600, Post Road, #114-341, East Greenwich, RI 02818, or call 1-877-527-0382.

Resources

The pamphlet "EPA's Volunteer Monitoring Program" is available from USEPA, Volunteer Monitoring, 401 M Street SW (4503F), Washington, D.C. 20460.

To obtain the national newsletter, send your name and address to The Volunteer Monitor, 1318 Masonic Avenue, San Francisco, CA 94117, or call 415-255-8049.

To learn how to purchase a map from the USGS, call 800-USA-MAPS. Seniors looking for volunteer opportunities should contact the Environmental Alliance for Senior Involvement (EASI). Write to EASI, 8733 Old Dumfries Road, Catlett, VA 20119

The Society for Amateur Scientists (SAS) is a nonprofit research and educational organization dedicated to helping people enrich their lives by following their passion to take part in scientific adventures of all kinds.