Starting around dusk you should be able to hear them calling if it's warm and humid enough for them to start breeding, and apparently you've been lucky enough to have a few nights like this so far

. The sound of the call should be enough for an ID for a Peeper and you can quite often get very close to them. My usual approach at night:
1) walk towards calling peepers and stop moving when they stop calling
2) stand still and wait for calling to resume, then go back to step 1) until you are close enough to see one (a flashlight is handy)
This usually works and if you ever have the notion to try to keep a Peeper permanently you should do this so you can witness first hand just how loud a male can be before bringing it into your home. They are shockingly loud for their size

. Not a problem if you're just raising and releasing though

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The puddle drying up before they make it to land is kinda sad (as is the snow after eggs have been laid!), but all part of their early breeding gamble and one of the reasons they lay so many eggs in one go. It's nice of you to want to try to save some though

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