Right after the sun set, we started hearing the peepers (we've been waiting for them). Peepers are tiny frogs (typically less than an inch long) and various shades of brown in color. They're hard to see, I've only seen them up close because my daughter, a nature girl, has been able to catch them at times. Their scientific name Pseudacris is from the Greek for "false locust" due to their vocalization and crucifer refers to the dark cross (an X-shape) on their back.
Males use their throat sack to make a single high-pitched call 15-25 times a minute to attract a female. Click here to listen to their singing.