On a chilly March evening my wife Cathy and I stood in the starlight facing a nearly invisible wetland. We were listening to what sounded like thousands of tiny sleigh bells tinkling in the darkness, but was actually the calls of male spring peepers competing for mates. We listened for perhaps three of the five minutes required by protocol, confirming that, indeed, there were too many spring peepers to pick out individual calls, and also that if we listened very carefully, we could just make out the clicking calls of one or two lonely western chorus frogs. And, then, in the fourth minute, we heard a sound definitely not that of an amphibian. First one, then another, and finally a whole chorus of coyotes yipped and howled somewhere in the darkness, uncomfortably close. We decided that, protocol be darned, we had all the data we really needed, and beat a hasty retreat to our car.

That night Cathy and I were participating in frog call monitoring, a citizen science project administered locally by the Champaign County Forest Preserve District. Like other frog call monitors, we had attended a training session led by district personnel in early February in which we learned monitoring protocol: only observe during suitable weather conditions, not too cold or windy. Begin observing at least a half hour after sunset. Note weather conditions and time of observation. For at least five minutes, record which species are present and whether one, few, or many are calling. We listened to the calls of 13 different species of frogs and toads, and were given a CD of calls so we could continue to learn them. Finally, we signed up for one or more monitoring sites in one of the district's five forest preserves. We chose Collins Pond and the seasonal wetland at Homer Lake. We were to observe twice a month for five months—March through July.

Why frog call monitoring? As the website of the University of Wisconsin Extension (http://clean-water.uwex.edu/pubs/pdf/frogstoads.pdf) notes, "A healthy wetland can provide many species of frogs and toads with ideal habitat, and the absence of frogs and toads in a wetland may indicate something has gone wrong. With their semi-permeable skins and a life cycle in which they spend part of their lives in water and part on land, frogs and toads are sensitive to contaminants in both terrestrial and aquatic areas within a wetland. They are also sensitive to wetland degradation caused by invasive species, sedimentation, and habitat fragmentation." In other words, frogs and toads are an important indicator species of the health of our wetlands. And, of course, they make noise, very loud and recognizable noise, so we can note their presence or absence.

Cathy and I enjoyed our monitoring sessions. Not only did we observe eight species of frogs and toads, some (like spring peepers) putting on incredible shows. We also saw gorgeous sunsets, planets and stars and even the Milky Way in dark skies, river otters, muskrats, bats, a forest full of fireflies and heard owls, migrating birds overhead, and, yes, coyotes. We eagerly look forward to the 2017 monitoring season.

During this past summer and fall, I volunteered at the Interpretive Center at Homer Lake, and entered the observations of all of the 2016 monitors into a spreadsheet. Chelsey Walsh, who oversees the program, hopes to have an intern analyze this and the data from four previous years to establish a baseline of where and how many frogs and toads occur in the preserves so they can observe long-term trends.

Roger Digges (2008)