Currents: Jonathan Poppele, naturalist and educator, of the Minnesota Wildlife Tracking Project

Today: Jonathan Poppele, director of the Minnesota Wildlife Tracking Project, which conducts citizen science projects in collaboration with the University of Minnesota and wildlife agencies and groups.

Nature guidebooks are my business. I have more field guides on my shelf than any other kind of book. Lately, I have been getting a lot of use out of "Animal Skulls" by Mark Elbroch and "Bird Feathers" by S. David Scott and David McFarland. I'm always trying to broaden my knowledge of animal track and sign, and often come back from the field with questions to research and photos of things to identify.

For the past couple of years, I have been following the shifting population of wolves at the Cedar Creek Ecosystem Science Reserve in East Bethel, Minn. Researchers discovered a wolf den on the property in spring 2015. It was the first time in memory that wolves had denned this far south in Minnesota — and this close to the Twin Cities. Because of concerns over livestock depredation, county officials called in wildlife services to remove the pack. Most of the wolves were trapped and killed over the course of two years, but one wolf avoided the traps. Cedar Creek researchers have deployed trail cameras across the reserve, and a Minnesota Wildlife Tracking Project team conducts regular track and sign surveys to monitor the wolf. Typically, a solitary wolf would range widely and not stay in one spot for long, but this animal has been sticking around for over a year. In our most recent survey, one of our teams found tracks that may have been from a second wolf. If that is the case, there may soon be another pack denning at Cedar Creek.

I usually have at least one or two astronomical observing projects going on. One of my current projects is drawing the surface of the sun as I see it through a hydrogen-alpha solar telescope. A hydrogen-alpha telescope blocks all of the sun's light except for a narrow band of ruby-red light emitted by hydrogen atoms in an excited state (for my fellow geeks out there, it is the 656 nanometer wavelength emission line — just a little longer than the light from an inexpensive red laser pointer, which has a wavelength of 650 nanometers). Unlike the white-light solar filters used in eclipse viewing glasses, hydrogen-alpha filters show the prominence on the edge of the sun's disk.

I have been enjoying the sound of cicadas drifting in through the windows of my home office. To my ear, the buzzing of the "dog-day" cicadas in the treetops is a consummate sound of late summer. A reminder that the days are shorter and autumn is coming.