Looking for frog call listening volunteers to listen for Western Chorus Frogs NOW! (April-May) at sites on record and report other locations also if heard
Spring is finally here and along with it the inevitable cacophony of calling frogs. One species, though, the Western Chorus frog (Pseudacris triseriata), may not be heard as often these days. It has seen precipitous declines over the past decade in Quebec, and in Ontario there are signs it may not be as widespread as it used to be. Last spring, David Seburn noted despite the presence of suitable habitat, the frogs were heard at only one of 20 Cornwall area sites where the frogs were heard in 1990.
As a result of these kinds of observations, COSEWIC plans to undertake an evaluation of the species next year to determine if it is “at risk” and if so, to what extent. Therefore there is an urgent need to ‘verify’ as many ‘historic records’ as possible for this species so that up-to-date information can be used. The NHIC has put out a call to SAR staff in the various districts urging them to help verify as many of the old records as possible.
The frogs breeding season starts now and stretches for next several weeks. Kemptville District MNR has ~500 records to check and there are gaps in information which it would be useful to fill. If there is anyone out there interested in helping with some quick checks of historic records in your area over the next few weeks, let me know and I can pass you on the necessary information. This would be an activity you would do on your own (with information & support from me) and the best time to do this in the evening. If anyone opportunistically hears Chorus frogs calling in the next couple of weeks (i.e. you’re not checking a records, but just happen to hear them while going about your business), please take note of the location, time, date to the best of your ability and let me know.
Instructions for verifying presence of Western Chorus Frogs:
• Chorus frogs are very hard to see, and so verification is through listening for their calls
• When breeding in the spring this species is easy to detect by its call, which is quite distinctive (likened to running ones fingernail over the teeth of a comb) – a recording of the call can be found at http://www.naturewatch.ca/databases/frogs/audio/pseudacris_triseriata.wav
• Ideal conditions for calling are mild, calm evenings (dusk to midnight), particularly during or after rain, though during peak breeding they will call during the day and at night
• Many of the sites are easily checkable from the road. I.e. you can drive up in your car, pull over and turn the engine off, get out and listen for a few minutes, and take a few notes (That’s it!)
• Reporting negative results (ie. Not hearing frogs calling in locations where they have been known before) is as important as recording where the frogs are found.
• I have been provided a spreadsheet with the details of all the historic records, including GPS locations – let me know if you are interested in helping out and what geographic area you want to check, and I’ll get you the relevant location information and the reporting form.
Deb Jacobs, A/ District Ecologist,
Kemptville District OMNR,
10 Campus Drive, Postal Bag 2002, Kemptville, ON K0G 1J0
Tel: 613-258-8235 Fax: 613-258-3920