Male dart frogs will call. Some species have a dull or quiet call while others have a loud and almost pleasent call. D. leucomelas and P. vittatus are two common species that have a nice trilling call. D. pumilio has a call that is a loud buzz. It's not very attractive or interesting but it's deffinetly loud. As far as chirps go there are a number of thumbnails that people have described as sounding similar to a chirping cricket, but I have little experience with them and haven't heard any calling before, maybe someone else can fill you in with more detail. Good luck,
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Devin Edmonds
devin@amphibiancare.com
www.amphibiancare.com