Every year starting in late March to early April, the chorus begins. The Western chorus frog is usually the first to find its voice with its ascending, constantly repeating crrreeek and it is quickly, if not simultaneously joined by the soprano chirp of spring peepers or the rumbling, snoring leopard frog bass. The singers are all males, and they are trying to attract a female for mating. The chorus can be deafening, but for those of us listening it is a welcome and sure sign of spring. And every year, since 1991, at wetlands across the state, dedicated volunteers have been there, listening and collecting data on what's singing.
These volunteers are a part of the Iowa Department of Natural Resources' Frog and Toad Call Survey. This survey is coordinated by the DNR's Wildlife Diversity program and our survey is one of the longest running in the country. In its long history, over 13,000 call surveys have been done on more than 1200 wetland sites in 82 of Iowa's 99 counties. Amphibians are currently in global decline and face many environmental stressors.
The value of this survey is multifaceted. The wildlife diversity program is small and without the dedication of these volunteers, it would be impossible to collect data over such a large area (statewide) and time period. The survey provides us with data that allows us to: 1) determine distribution range extensions, 2) monitor population trends and 3) have an index for water quality.
The survey was started because of serious concern over the global, precipitous decline of many amphibian species. This decline is most often attributed to ever - increasing pollution in aquatic environments. All amphibians spend at least part of their life in the water and due to their highly permeable skin they are very sensitive to pollutants. Declines can also be due to other factors such as habitat loss (Iowa has drained ~ 95% of its wetlands), or invasive species such as the bullfrog which in Iowa has been expanding its range. It is an aggressive predator of other frog and toad species.
Interested in getting involved?
By attending a VWMP frog and toad training workshop, you can help with this important work. Routes are set up across Iowa and trained volunteers are needed to adopt and survey these routes. Participants in the Frog and Toad Call Survey workshop will learn to identify Iowa's frogs and toads by sight and sound, and then how to collect and report data to the Wildlife Diversity program. Volunteer-collected data is used to monitor the status of these amphibian species in the state. Keep an eye on the website for dates and locations.
List of Available Routes with Maps
To find out more about how to get involved in the Frog and Toad Call Survey, contact the state coordinator, Stephanie Shepherd at 515-230-6599, vwmp@dnr.iowa.gov. Thanks for your interest!