There are a few species of frog that live in noisy habitats where their calls would be masked by the sound of rushing water. These frogs apparently attract a mate by visual rather than auditory means,hopping up and down and waving their legs to catch the eye of the females. Frogs are silent when hunting their food which consists of live insects. Probably the most common experience we have of feeding frogs is the tree frog miraculously stuck to the window, hunting moths attracted to the light. If you watch them you may be lucky enough to witness the quick leap towards their prey but you will not be able to see the sticky tongue shoot out, adhere to the prey and haul it back into the mouth, all done in a flash.
Frogs really are deadly hunters, despite their soft squishy image. .
Listen for the solo species and the choral species. Note the differences between species and estimate the number of species sharing the wetland. Listen for the variation within a species. Try to imagine which call is most attractive to a prospective mate. Look for frogs.