According to the birds, there are two Maines. Interestingly, the dividing line corresponds roughly to the 45th parallel — the latitude that bisects the Northern Hemisphere, halfway between the equator and the North Pole. In Maine, this line runs across the middle of the state, from Rangeley to Perry, placing the state smack dab in the middle of the temperate zone.
It just so happens that the 45th parallel aligns remarkably well with a major habitat transition. In Maine, hardwood forest dominates the landscape over the southern half of the state, with scattered pines and hemlocks providing most of the winter greenery. Above the line, softwood begins to take over. Fir, spruce, cedar and tamarack grow in spots that are cool and damp.
Farther north, spruce dominates the northern forests of Canada. But the transition zone from hardwood to softwood begins right here, and we get to watch its effect on the birds. The 45th parallel passes through the north end of Old Town, and there are many birds that are seldom seen south of this line. Some of the warblers that nest above this latitude include Cape May, Tennessee, bay-breasted, blackpoll and mourning. Several year-round species also are found mostly north of this line. If you want to find boreal chickadees, gray jays, spruce grouse, black-backed woodpeckers and American three-toed woodpeckers, you’ve got to get above the line.
Likewise, there are some birds that are seldom seen north of the line. The range of the prairie warbler stretches from the southern tip of Florida to the 45th parallel, but I’ve never seen one north of Orono.
The glossy ibis and snowy egret are common in southern Maine. They are rare up here.
Of course, terrain has a lot to do with the range of birds. Mountains provide spruce habitat at higher elevations well south of the line. Coastal maritime forests are cooler and wetter, fostering spruce and fir as far south as Vinalhaven. I’ve seen boreal chickadees on this midcoast island.
But not lately. I used to see them in Stonington, too, but it has been a long time since my last encounter.
As the climate warms, northern birds are retreating. Southern birds are expanding. Northern cardinals have now reached Canada. Tufted titmouse, red-bellied woodpecker and Carolina wren are moving north. Turkey vultures now soar over Aroostook County. Less desirable southern critters, from ticks to opossums, also are moving north.
The moral of the story is this: get out and bird both Maines. Fish crows, orchard orioles, piping plovers, field sparrows, least terns, saltmarsh sparrows and yellow-throated vireos are found almost exclusively in southern Maine. Grasshopper sparrows are found at Kennebunk Plains, and practically nowhere else.
An early summer excursion around southern Maine’s parks, beaches and land trusts is a vastly different experience than the woodland adventures of northern Maine. Go south.
Then go north. Bird the other Maine above the 45th parallel. Wander Baxter State Park. Seek out one of Maine’s public reserved lands. Fork over the $7 daily fee and explore the realm of the North Maine Woods. There are 3.5 million acres full of logging roads, unspoiled lakes and spectacular vistas. Stay aware of the rules of the road. Watch out for trucks, avoid active forestry operations, fill up with gas, and bring a spare tire. Go wild.
That is what draws me above the 45th parallel. Backyard birding is fun, but it pales in comparison to a walk down a dormant logging road deep in the Maine forest. The density and variety of birds is astounding, and I am far enough away from civilization that I am sharing the woods with wildlife instead of people. Last week, I startled a mink with babies along a river bank. The parent grabbed one squealing youngster by the scruff of the neck and carried it from my sight. The other tiny minklet froze in place, lingering silently for several minutes until it, too, was carried away. One can only imagine the family discussion about who got rescued first. “Mom loves you best.”
My fascination with birding the North Woods borders on addiction. I spend time on Google Earth, searching satellite photos for odd places that are reachable by logging roads — places where unusual birds could be hiding. From high above, you can pick out bogs, conifer stands and beaver flowages.
There are millions of acres I haven’t explored yet. I suspect the other Maine is going to keep me busy for a while.
Bob Duchesne serves as a Maine Audubon trustee and vice president of its Penobscot Valley Chapter. Bob developed the Maine Birding Trail, with information at mainebirdingtrail.com. Bob can be reached at duchesne@midmaine.com.