Volunteers sought for annual frog and toad survey

The Friends of the Rouge are seeking volunteers to participate in their annual Rouge River Watershed Frog and Toad Survey.

The Friends of the Rouge have been conducting this survey since 1998 in order to monitor the health of the wetlands as the presence of several species of frogs and toads is an indicator of good wetland health.

“They are very sensitive and require a good quality of wetland,” explained Sally Petrella, the volunteer monitoring program manager for the Friends of the Rouge. “They need a good upland habitat as well because they are amphibians. So they spend part of their life cycle as tadpoles in the water and then spend part of their adult life in another habitat.”

Petrella added that healthy wetlands are “critical” to the health of the whole river system.

“They help to filter rain water. They act like great big sponges when it rains. They also help control flooding and provide a great habitat for birds, frogs, toads, and other animals,” she said.

Volunteer training begins this month when volunteers attend a two-hour workshop to learn how to differentiate between different species of frogs and toads.

“It’s a listening survey,” she said. “We need volunteers to sign up for the survey teams and learn how to identify the calls of our local amphibians. It’s not really difficult as there are only eight calls they need to learn. It’s not as difficult as learning bird calls, of which there are hundreds. The calls are pretty distinct such as the ‘peep, peep, peep’ of the spring peeper and the ‘rum, rum, rum’ of the bullfrog.”

The survey includes identifying seven species of frogs: the wood frog, the western chorus frog, the northern spring peeper, the northern leopard frog, the gray treefrog, the green frog, and the bullfrog. There is also one species of toad — the American toad — targeted during the survey.

Petrella said volunteers have noticed the more tolerant amphibians since 1998, such as the green frog and the American toad, are becoming the most common in the watershed.

“This suggest that some frogs and toads can survive in this very urbanized watershed, but it also tells us we need to do a better job of creating a habitat for the more sensitive (species),” she said.

While the least sensitive species is the American toad, Petrella said the most sensitive is the northern leopard frog. Although this particular species is not common in the Rouge River watershed now, Petrella said she believes they used to be very common in the watershed based on previous reports.

The actual surveying begins in March once the temperature reaches above 46 degrees, and continues through July, which is the peak breeding season for the frogs. Volunteers go out on their own on warm, damp evenings to survey a few times a month. All the data is then compiled and provided to surveyors in local communities, as well as the state.

Petrella said the survey is one of group’s most popular.

“It’s a really fun survey, and my volunteers always report that the thing they like about the survey the most is hearing the frogs and toads,” she said. “It’s fun to learn a new skill and to be able to identify in the spring the calls of the chorus frogs and the spring peepers.”

In order to volunteer, one must register and attend one of four training sessions and identify a block within the River Rouge Watershed that is close to them. For more information on the volunteering and training sessions, contact monitoring@therouge.org or call Petrella at 313-792-9621.