Mreakkk mreakkk. If you wander near Kettle Hole Marsh, it is nearly impossible to avoid the enveloping the racket of the chorus frogs. The western chorus frog is the smallest frog species in Minnesota, but you wouldn’t know that from their boisterous noise-making! They aren’t the only frogs in the Arb: there are gray tree frogs, Cope’s grey tree frogs, bullfrogs, green frogs, and the northern leopard frogs.
The vocal awakening of the Arb’s frogs marks an important spring tradition - the annual frog and toad survey! This survey parallels an annual survey sponsored by the MN Department of Resources, which was created because of concerns about the global decline in amphibians, as well as an interest in how local frog and toad populations are changing throughout the United States. Amphibians are often a good bio-indicator of environmental health, and knowing their populations in the Arb is an important measure for assessing restoration efforts.
Taking part in the frog and toad survey is definitely one of the cooler ways to get involved in the Arb. The survey begins 30 minutes after sunset and traces a route that meanders from the upper Arb along Spring Creek, around the various ponds in the lower Arb, through the floodplain forest and to the Iron Bridge. Frog and toad populations are approximated by how frequently the calls of each species are heard at each survey spot. When I participated in the survey, it was a beautiful, clear night, the stars were out, and I really enjoyed the opportunity to just listen to the Arb and its abundance of night sounds (specifically, the diversity of frog calls). It was a captivating experience! If you want to get involved, there will be a survey outing later in May. Information about previous frog and toad surveys can be found on the Arb website.