Now that the season has crept into May, the trickle of migrant birds returning north is gaining strength and moving closer to the wave that will arrive by mid-May. Already, birders from across Maine are reporting their first-of-year rose-breasted grosbeaks and black-throated green warblers and great-crested flycatchers. Each day brings more and more birds. Our dawns are filled with a cacophony of song.

Those billions of birds migrating north each spring represent a slice of the biodiversity of our planet and a unique part of the global heritage of life. With modern technological advances in the study of migration, we now know that even the tiny among these creatures accomplish unimaginable feats of endurance, flying nonstop for days over the open ocean with no food or water, and no place to stop and rest. They come back north each spring for the promise of a place to nest and raise their young. It’s hard to imagine what it might be like for them, after pushing their way northward over thousands of miles across a hemisphere, to arrive back in the familiar neighborhood where they raised their young or perhaps where they themselves were raised. Most birds come back relatively close to the area near where they were raised, and adults tend to come back to almost the exact same spot where they nested in the previous year. Is it possible that they feel a sense similar to what we would call relief—dare we say joy?—when they arrive at that spot and see the same tree where they built last year’s nest?

But what about the bird, maybe a blackburnian warbler, that has flown through dark skies, north from Ecuador where it spent the winter, over the teeming forests of Central America, across the Gulf of Mexico to the coast of Texas or Louisiana and then north, night by night, over weeks of travel, to arrive at an empty space where the spruce trees that had held last year’s nest had been? Maybe the trees needed to be removed to make way for a road or a new building, or were harvested in a forestry operation. The bird is faced with a difficult situation. Find a new place, fight for a new territory, or die.

We humans can’t stop all loss of habitat as we ourselves need places to live and food to eat, and that means we, like all other living things, consume resources. But we need to find a balance. Famed scientist E.O. Wilson, in his new book Half Earth, argues that we need to set aside at least half of the Earth to sustain life and to guarantee clean air and water for the generations of people to follow. When we have a chance to place important lands under protection to ensure that there is space for birds and mammals and fish and insects and plants, we should vigorously embrace it.

Here in Maine, we have such an opportunity.

We can build on Governor Baxter’s visionary idea that created Baxter State Park by establishing an 87,500-acre National Monument in Maine’s treasured North Woods. The owner of the land wants to give it, along with a generous endowment, for the establishment of a National Monument as a first step toward a National Park and National Recreation area that would help build a new economy for people in the region and provide recreational opportunities for visitors. On Monday, May 16 at 5 p.m. there will be a public meeting in Hauck Auditoriam at the University of Maine, Orono with National Park Service Director Jon Jarvis about this chance to make history. To learn more or to stay informed, visit www.nrcm.org.

Such a place would also provide a safe haven for hundreds of thousands of those very birds that are migrating north across the Americas, with no reason to assume their nesting grounds won’t still be there. To help ensure it is, learn more at www.nrcm.org.

Jeffrey V. Wells, Ph.D., is a Fellow of the Cornell Lab of Ornithology. Dr. Wells is one of the nation's leading bird experts and conservation biologists and author of the “Birder’s Conservation Handbook.” His grandfather, the late John Chase, was a columnist for the Boothbay Register for many years. Allison Childs Wells, formerly of the Cornell Lab of Ornithology, is a senior director at the Natural Resources Council of Maine, a nonprofit membership organization working statewide to protect the nature of Maine. Both are widely published natural history writers and are the authors of the book, “Maine’s Favorite Birds.”