CHICAGO WILDERNESS CALLING FROG SURVEY

 INTRODUCTION 

 We are proud to announce the fourth year of the calling frog survey for Chicago Wilderness.  Before the Calling Frog Survey began, very little was known about the distribution and status of amphibians within Chicago Wilderness.  Not any more!  The Calling Frog Survey is providing important information to scientists and land managers, who can use the data we collect to conduct management and research that benefits amphibian populations. 

 In 2001, data from this survey were used by a local scientist to identify the most important habitat variables for frog and toads.  The data currently are being incorporated by the Northeastern Illinois Planning Commission into a regional planning model that will identify the highest priority wetlands for protection and restoration.

 As we document the distributions of the 13 species of frogs and toads in the Chicago Wilderness region, we will be able to track changes in these distributions over time.  We will know, for example, if a population has disappeared from a particular wetland, or if a species has been found in a county where it was previously unknown.  We will be able to document long-term trends in amphibian populations and to compare species distributions among different counties or habitat types.  We also will be able to compare species distributions among locations receiving different types or intensities of ecological management.

 The volunteer “citizen scientists” who monitor the frogs and toads of Chicago Wilderness are the heart of the Calling Frog Survey program.  Along with area scientists and land managers, we collect the data, analyze the results, and share what we’ve learned with the public.  We thank you for participating, and we look forward to another fun, productive year of monitoring. 

 NEW IN 2003: 

If you would like to visit your monitoring sites during both evening and daylight hours, you can monitor salamanders, snakes, and turtles in addition to frogs and toads.  This year’s monitoring workshops will provide training in search techniques and species identification for those who’d like to start monitoring the rest of our local amphibians and reptiles. 

And we’ll continue to hold our popular Chicago Wilderness Great Herp Searches.  We’ll gather at several sites again this year for group monitoring of reptiles and amphibians.  Expert monitors and herpetologists will join us, to provide training in identification and search techniques.  These events are great fun, and they allow us to gather large amounts of data in a short time period.

WHAT IS A CALLING FROG SURVEY? 

WHAT HAPPENS TO THE DATA?

1. Data from the Chicago Wilderness Calling Frog Survey is entered into a database, where it can be easily accessed by anyone wishing to use it.  You either enter the data yourself, or you send a handwritten copy to your county coordinator, who forwards it to the Chicago Wilderness Habitat Project for data entry.  In either case, we like to keep a written copy.

2. The information is passed on to the appropriate land owning agency, such as the county forest preserve district, to aid in the land management process.

3.  Individual researchers, herpetologists, planning agencies, and students can access the data for research and planning projects. 

4. The result is that the information is widely shared, so that scientists will have access to it when planning studies, and will be alerted to areas in need of research.

 PHENOLOGY OF FROG AND TOAD BREEDING

 Each frog and toad species has a specific period in which chorusing and mating are most likely to occur.  The timing of the breeding period is influenced by a combination of factors such as daily rainfall, soil, water and air temperatures, and photoperiod.  In northern Illinois, there are three distinct periods in which different species can be expected to breed.  Monitors must conduct at least one survey for each of these periods.  These periods, and the species that breed in them, are as follows: 

1. Early Spring (March 15- April 20) -  In most years this period begins in the final two weeks of March and lasts until mid-April.  Species which chorus during this period include: western chorus frog, spring peeper, wood frog, northern leopard frog and pickerel frog. 

2. Mid-Spring (May 10 - May 30) -  In most years this period begins in early May and lasts throughout that month.  Species include:  American toad, Fowler’s toad, eastern gray treefrog and Cope’s gray treefrog.

3. Late Spring/ Early Summer (June 20 - July 10) -  In northern Illinois, this period usually begins around the first week of June, lasting through July or early August.  Species include:  cricket frog, green frog and bullfrog.

 Some species, especially the American toad, western chorus frog and northern leopard frog, occasionally chorus well after their normal breeding seasons are completed.  This is most likely to happen during the cold weather of fall, or when cold summer weather systems stimulate early spring breeders.

 The length of the breeding season varies from year to year and from species to species.  The wood frog, for example, is an explosive early spring breeder.  Wood frogs may begin chorusing at any time after the spring thaw, but all breeding activity is completed in two weeks or less (often just one to three days).  Other species such as the western chorus frog, American toad and leopard frog may chorus during all three breeding periods. 

 It is very important to be aware of weather conditions and be somewhat flexible when planning which nights to be in the field, especially during the early spring period.  Volunteers may wish to sign up for the frog monitoring listserve at ChiFrog@topica.com, so that they can learn from other volunteers about the best nights to conduct surveys.  Ideal weather conditions for most frogs and toads can best be described as seasonably warm, moist (light rain or foggy), with no more than light winds.