The following was published in the Biddeford-Saco Journal Tribune Sunday edition, 12/15/13  (and may also appear, with other goodies, in members' mailboxes shortly...):

Normally, I do not talk to dead opossums. But since I’d watched this one keel over right in front of me, I felt I had to say something.

“You’re not dead. You’re playing ‘possum,” I said. She lay next to the Wells Reserve’s entrance garden, a furry mound of pink and grey. I waited. The November moon rose slowly behind us.

“I saw you roll over as I walked up. You and I both know you’re not dead.” Unable to escape the accusation, Mama Opossum rolled back over and waggled into the night, shooting one last hiss at me over her shoulder. It was a priceless moment.

But what if I could put a price on that interaction, or the countless others I have with nature here at the Wells Reserve at Laudholm? Maine is a trove of natural riches, jealously guarded by long winters and a stubbornly small economy. When it comes to the outdoors, we are a fortunate people, especially because we pay so little for what we get.

How much are the weekend hikes that I take with my family worth? Despite the $10 we dutifully deposit at the unmanned entrances of Maine’s state parks, if we sat down to calculate what we actually got back, I think we’d be a few thousand dollars short. The fresh air, the exercise, the time spent as a family, the views we get and the discoveries we make – and that’s just the beginning.

For some time now, researchers across the globe have been trying to quantify what humans get from nature. Society profits from these “ecosystem services” but no dollars are exchanged, despite the literally life-saving nature of these gifts. We’re a species of ecological takers.

In soil created long before we arrived, the sun grows trees and we cut them down. Within the wood houses we build, we burn oil and gas we merely found. We run metal appliances with electricity made from waterfalls, wear wool from sheep we did not invent, and eat fruits pollinated by the wind, the birds, and the [disappearing] bees who slave away in our fields for exactly $7.25 less than the federal minimum wage.

Here on the coast, fresh waters feed the sea and the sea in turn feeds us. According to the Wells Reserve’s own research department, the 1,600 acres of the Webhannet River estuary likely incubates 5,000,000 fish per year, which use the marsh for feeding, shelter, and reproduction (Dionne, Short, and Burdick, 1999). Those fish reenter the Gulf of Maine each year as essential strands in the food web, and local anglers and fishing fleets rejoice. Sweet shrimp, we only miss you when you’re gone.

The sun is never late to work, the moon thanklessly hauls in the tide, and the earth continues to provide. This holiday season, as you give and get for those you love, I hope you’ll take a moment to give something back to the greatest, least appreciated giver of all: the planet we’re lucky enough to call home.

Nik Charov is president of Laudholm Trust, the nonprofit partner of the Wells National Estuarine Research Reserve in Wells, Maine. His Sunday Journal Tribune column, "Between Two Worlds," ventures forth from the intersection of art and science, past and future, earth and stars. More at wellsreserve.org/twoworlds.