We were successful with most of our funding applications this year! Thanks very much to our supporters at the Government of Canada’s Habitat Stewardship Program, as well as the B.C. Habitat and Conservation Trust Fund. With these funding announcements in place, we’re able to start the work.
Over the last month, I have been out in the field doing midnight bullfrog surveys, habitat vegetation surveys, and planning for the upcoming construction season.
Beware the Bullfrogs
Bullfrog surveys are very important to the management of our native amphibians, as this introduced species causes havoc everywhere it goes. It travels far and wide, eating anything small enough to fit in its mouth. (Check out this video from National Geographic!)
The bullfrog, native to eastern Canada and the US, was introduced to BC for commercial frog-leg farming. Frog farms were promoted as employment and business opportunities for returning veterans after WWII. These farms failed, and the bullfrogs were released to the wild. Aquatic garden supply companies catering to newcomers to the province that missed the “sounds of summer” also imported these predators to stock backyard ponds. Now these sounds of summer can be heard all across Vancouver Island and the Lower Mainland, at the expense of our native amphibians. Check out The Bullfrog Project for more information on bullfrogs on Vancouver Island.
We’re just getting a handle on the extent of the bullfrog populations in B.C. We know that they are as far east as Deroche and Nicomen Slough on the north side of the Fraser, and that they are in east Chilliwack but not yet in Rosedale. We want to figure out what the boundary is between bullfrog presence and absence.
In our search for suitable introduction locations for the Oregon spotted frog, we also need to ensure that we don’t inadvertently feed a burgeoning bullfrog population with our precious OSF. Unfortunately two of our potential release locations have been found this spring to have bullfrogs present.
Help us out!
If you live in the Fraser Valley, we’d be delighted to have your help. Bullfrogs typically call from mid-June to mid-July, after dark at the end of a really hot, steamy summer day.
To survey for bullfrogs near your home, slap on some bug-repellant and pull up a chair beside your local water-body. waterbody could be a backyard pond, a stream, a ditch, a slough, or even a farm dugout.
Listen carefully. The Bullfrog calls are very deep and slow, and you can find plenty of recordings on youtube, or on this page.
The other frog you’re likely to hear is the green frog, also invasive. They’re everywhere by now – if you have bullfrogs, the green frogs are sure to have started up the chorus. They mostly sound like the twang of a large elastic band, and sometimes rise into an almost-bullfrog-like croak. If you’re not sure of what you heard, try recording it with your phone or a tape-recorder and send it to me.
While we’re on the subject, that chorus of chirping you’re hearing is the Pacific chorus frog (recently the Pacific tree frog). This little guy makes the biggest sounds!
Bullfrog call surveys are only reliable after dark following a hot summer day. If you’ve listened for a whole hour without hearing a bullfrog, you probably have a bullfrog-free pond!!
Take notes about your survey: date, location, start/end time, temperature, weather that day, and what species you hear and I’d be delighted to have the data.
Thanks for reading, and Happy Frogging!
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