If you spend any time at all outside in Wisconsin this time of year, you know that things are happening… you might hear the sandhill cranes croaking, the loons hooting, or the frogs peeping, sometimes at astonishing volumes. In the lakes and streams, nymphs and fry are starting to stir, as are the fish that eat them. In a week or so, sometimes less, all this will shift, and a new cast of ecological characters will strut their stuff, caw, trill or boom. So, if you’re interested in this constantly changing account of what’s happening right now, right here, and in this weather, you’re interested in what’s called phenology. Mike Miller is a water management specialist with the Wisconsin Department of Natural Resources.