Wildlife biologists band egrets at Baker’s Lake. (Forest Preserve District of Cook County)

Cook County’s forest preserves are much loved for their picnic groves and trails. Not as well known: The forest preserve district’s role as a research hub and early warning system of sorts against zoonotic diseases.

North American river otters, once nearly extinct in Illinois, are a great comeback story. (Grayson Smith / U.S. Fish and Wildlife Service)

The Urban River Otter Research Project recently launched in Cook County. One of the early goals is to gather otter sightings from the public in order to get a sense of the extent of the animal’s presence in and around Chicago.