Biologist Matt Burne makes his way up a steep, rocky trail in the Middlesex Fells Reservation. His sons, Mason, 10, and Liam, 8, follow close behind. Dark clouds fill the late afternoon sky, and thunder rumbles in the distance. Pausing atop a rocky outcropping, Burne scans the woods below.
“It’s right down here, kids,” Burne says, pointing to a small pond a couple hundred feet away, surrounded by white pines, red maples, and sweet pepperbush.