North on the Wing

by Bruce M. Beehler

  Tranquillo reported that there had recently been a decent migrant arrival. He showed me netted Kentucky, Hooded, and Swainson’s Warbler individuals as well as a colorful male Painted Bunting. I’d arrived at Nunez at the beginning of the high season for songbirds coming across the Gulf. As was the case at High Island, these birds were arriving from their overwater journey in the afternoons—the birds I’d spotted this morning had arrived on an earlier afternoon and were resting and refueling before continuing northward into the heart of the continent. The woodland here (unlike the tiny woodland patches of High Island) was large enough to keep the migrants around for a few days. The netting team captured seventy-five birds that busy day at their banding camp, situated in a screen tent tucked into the southern edge of the woods. Tranquillo processed birds throughout the morning and afternoon, and out in the woods Sullivan and Granger pulled birds from the nets almost continually.

  I added a second breeding warbler to my quest list: the Northern Parula. I found the tiny canopy-dweller in a Spanish moss–draped Live Oak in the interior of the woods. This, the smallest wood warbler, is an energetic vocalist that prefers high-canopy twigs for its singing and foraging. Blue-gray, yellow, and white, the species is distinguished by its dark collar, broken white eye-ring, white wing-bars, and the yellowish patch on its back. It is interesting that no wood warblers besides this one breed in the coastal woodlands—the habitat simply must not provide enough breeding-season sustenance to support these voracious insect-eaters. Yet the Northern Parula is one of the most widespread and adaptable of the warblers, breeding in coastal Live Oaks as well as the North Woods boreal forests. I would encounter this little sprite again in various places along my route to Canada.

  On my second morning at Grand Chenier, I saw flocks of small, dark birds moving along the woodland edge as I drove down the entrance track to Nunez Woods. There had been a migrant arrival at the end of the preceding day, and now the woods, edges, and grasslands hosted hundreds of Indigo Buntings, White-eyed Vireos, and Summer Tanagers. Several other migrant species were everywhere—Kentucky and Hooded Warblers, Scarlet Tanagers, and Blue Grosbeaks.

  Birding in Nunez Woods was fascinating because of its strange ornithological juxtapositions. This morning, two distinct ecosystems intersected: as I stood in the forest, looking at Hooded Warblers on the ground and Summer Tanagers in the canopy vegetation, I could see large waterbirds just above the treetops, winging over our little patch of woods. White Ibises, Tricolored Herons, and Great Egrets were on the move from one large wetland to another. One does not expect to be able to watch furtive wood warblers and colorful herons on the same spot of habitat, but this is the kind of treat birders encounter in southernmost Louisiana.

  The Nunez team was excited by the presence of a male Cerulean Warbler foraging prominently in a big Live Oak just around the bend from the banding station. Indeed, blues, as well as reds, were to be the themes of this day. Bunches of all-red male Summer Tanagers foraged in the forest and loafed at the edge of the woods. Flocks of Indigo Buntings, joined by larger Blue Grosbeaks, foraged low in the grass and flushed up into the bushes and trees at the edge of the woods each time I walked by. Nervous flocks of twenty to thirty deep-blue bunting and grosbeak males were joined by the brown females of the two species, and the two-tone flocks started up from the field in a dozen intermittent explosions of deep blue and buff brown. To date on my trip, I had recorded 166 bird species without expending much effort—I’d just put myself at the right places at the right times.

  On this trip, as I would discover, flocks of Indigo Buntings followed me up the Mississippi Valley to their northern breeding limit at the Canadian border. This bunting—the male a deep ocean blue and the size of a small sparrow—became my colorful little mascot: I’d encountered small groups of them at Jackson Prairie Woodlot, and there were flocks of dozens here. As a youngster in Baltimore, I had found singing Indigo Buntings on territory in virtually every woodland clearing I explored. I loved their complex and rollicking song—an insistent sweet-sweet…, followed by four distinct repeated phrases—but, because of their abundance, I’d taken the birds for granted. Now, on this long road trip, I was regaining respect for the bright little songbirds, mainly because of their flocking habit and their omnipresence. Here was a Neotropical migrant, one that wintered in Mexico and the Caribbean, that was truly prospering, and I saluted their success as travelers and widespread North American breeders.

  Meanwhile the Nunez Woods banding crew was hard at work. Wearing tall rubber boots, they slogged the woodland trails almost continuously as yet another rainstorm pounded the paths into a deep slurry of soft mud and standing water. The nets were catching lots of migrants and there was no time to shift them to a drier set of trails, but the joy of intimate encounters with the diversity of colorful songbirds dulled the annoyance of the all-encompassing mud. The staff and I were paying a small price for a unique experience.

  The data on fat and muscle condition that Tranquillo collected from the netted birds indicated that the migrants had arrived in good shape after their Gulf crossing, and the birds I spotted out and about appeared fine, despite the nasty weather they had encountered. Even the tiny hummingbirds seemed unaffected by the Gulf crossing. Of course, their health shouldn’t have been a surprise. Natural selection has operated on these songbirds for thousands of generations, and the results of that process are clear: the trans-Gulf route is their best route north.

  I had now completed my southern coastal tour. My count of wood warblers on their breeding grounds remained at two, but I knew that about a dozen species bred in the extensive interior forests of the Mississippi bottomlands, where I was headed next. I had observed along the coast a number of passage migrants on their way to the Great North Woods to breed—Swainson’s Thrush, Blackpoll and Magnolia Warblers, and Philadelphia Vireo, among others. The wood warblers would lead me north week by week. Heading north from Nunez Woods, I would next hunt for productive migrant stopover sites in the Deep South’s interior. Ahead of me lay the Mississippi’s once vast and forbidding ancient bottomland forests, at one time the land of the Cougar, the Red Wolf, and the Ivory-billed Woodpecker.

  FOUR

  The Low Country of Louisiana and Mississippi

  Mid-April 2015

  Hooded Warbler

  Each time we crossed a brook among the wooded ridges, on that day of warblers, we stopped. For there we were sure to find a pocket of migrants. The trees beside such streams were always filled with the song of the spring woods, the small and varied music of the warblers.

  —EDWIN WAY TEALE, North with the Spring

  From the Gulf Coast, my path leads me north into the interior bottomlands of Louisiana and Mississippi, with their mix of hardwood swamp forest, river oxbows, row-crop agriculture, and the tiny old towns of the lower Mississippi. The ecologically rich, junglelike forests of the Mississippi Delta are the places that Gulf-crossing migrant warblers hurry to reach after their brief stopovers in the coastal cheniers. More than twenty species of wood warblers pass through here en route to parts north, and populations of thirteen migrant wood warblers actually stop to breed in these forests. How many breeders will I find, and how many passage migrants will I see? And what environmental conditions will my quest birds face?

  Before I departed Grand Chenier, a terrific supercell storm struck, with black skies, sheeting rain, and powerful gusts. Luckily, I had broken down and stowed my tent, but the refuge hostel, where I took shelter, rocked on its tall support timbers. Several nearby trees crashed down. Spring on the Louisiana coast is punctuated by a succession of violent storms that typically pass from west to east, and one never knows in advance if a twister is embedded in a dark and swirling mass of cloud. Although not quite hurricanes, these events are fearsome.

  Driving the back roads, I saw that the chenier woodlands east of Grand Chenier had suffered a dieback, rendering the area less welcoming to arriving migrants. The dieback was a product of saltwater inundation from the
hurricanes that made landfall here, and decades will pass before these cheniers recover. North of Pecan Island (a town, not an island), I came to cultivated rice fields alive with Fulvous Whistling-Ducks and other waterbirds; I was leaving the vast and lonely expanses of marshland and arriving in inhabited farmlands with crawfish ponds and cattle pastures. Here many farmers cycle their fields from rice to crawfish and back to rice, which can produce bird-friendly wetland habitat. Both depend on seasonal flooding of diked fields, and both provide good foraging opportunities for shorebirds, long-legged wading birds, and waterfowl. Ducks Unlimited (DU) works with farmers in southern Louisiana and southeastern Texas to create waterbird-friendly winter wetlands, an effort partly funded by the U.S. Department of Agriculture through its Natural Resources Conservation Service.

  Passing through the decrepit town of Opelousas, I entered the watershed of the Atchafalaya—the river that is trying to capture the lower Mississippi. Where the Atchafalaya passes close by the Mississippi, the Atchafalaya is the lower watercourse. Thus, if the paths of the two meet, the Mississippi will be drawn down into Atchafalaya’s lower basin and follow its course to the Gulf. The Army Corps of Engineers has spent many millions to prevent this catastrophe of their own creation (more about the Corps’ misdeeds later in this chapter). If the Atchafalaya does capture the Mississippi, Baton Rouge and New Orleans will lose their river and the Mississippi will flow into the Gulf about seventy-five miles west of where it does today. The Atchafalaya, created by the confluence of the Red and Black rivers, meanders in a big, swampy bottomland that I crossed as I headed eastward on Highway 190 toward the town of Lottie. I drove several miles atop a raised causeway passing over the swamp forest of Atchafalaya National Wildlife Refuge.

  I needed my GPS to navigate this little rural patch of low country that has been much confused by the periodic shifting of the two big rivers and their various tributaries. In the balmy afternoon, I traveled back roads past the small communities of Blanks, Livonia, Frisco, Parlange, and Mix, finally coming to the prosperous town of New Roads. The country here is pretty: a mix of tall woodland and agricultural fields bounded by neatly planted rows of trees. Cattle Egrets forage in the fields, and it has the feel of Virginia horse country but without any prominent hills. At Pointe Coupee, I crossed the Mississippi on the John James Audubon Bridge, a graceful engineering marvel of concrete and steel completed in 2011. It is the second-longest cable-stayed bridge in the Western Hemisphere. The swirling brown river was in flood, and lots of bottomland was underwater.

  On the east side of the river is West Feliciana Parish, home of the historic town of Saint Francisville, just uphill from the ancient community of Bayou Sara, right on the main stem of the big river. I was here to visit Oakley Plantation, where John James Audubon once worked while he was struggling to become America’s ornithologist. And, of course, I’d come in search of the various wood warblers that nest in this low country—the same birds that Audubon marveled at nearly two centuries ago.

  NORTH AMERICA’S FLYWAYS

  The geographic paths followed annually by the low-country wood warblers help to define what is known as the Mississippi Flyway, a route up the middle of the country that is traveled by tens of millions of birds every year. Bird migration north and south across the continent follows natural pathways created by major physical features: the rivers, mountain ranges, and coastlines that link major breeding grounds to wintering grounds. Four flyways have been delineated by the concentrated movement of birds of various kinds in the autumn and spring. In eastern Louisiana, I was currently in the heart of the Mississippi Flyway. To the east lay the Atlantic Flyway, and to the west the Central and Pacific Flyways. Flyways are idealized simplifications of the messy reality of the migratory routes taken by the hundreds of bird species that move long distances between nesting and wintering habitats. Still, the concept is useful, as it highlights the geography and magnitude of the migratory phenomenon.

  The Atlantic Flyway lies between the crest of the Appalachians and the coastal waters of the Atlantic Ocean, from Labrador to Florida. Birds use this route in many different patterns. Some, such as the Broad-winged Hawk, migrate south along the mountain ridges of the interior. By contrast, the Peregrine Falcon migrates along the Atlantic coastline. Some Hudsonian Godwits travel from Alaska to the coast of New England in autumn and then fly nonstop south across the Atlantic to northern South America. Some shorebirds and waterfowl breed in Alaska and cross Canada before taking the Atlantic route south. The Black-throated Blue Warbler, one of my quest birds, migrates mainly along the Atlantic Flyway and is relatively rare along the Mississippi.

  The Mississippi Flyway follows the natural pathway offered by the great valley carved by that river’s main course. Large numbers of songbirds, waterfowl, and shorebirds use this direct route from breeding grounds in Canada and Alaska to reach wintering areas in Mexico, the Caribbean, and South America. This, of course, is the flyway that features the trans-Gulf crossing. The western verge of this flyway merges imperceptibly into the Central Flyway in the Great Plains to the west.

  The Central Flyway crosses a mix of plains and mountains as well as arid lands. The route leads from northern Canada south across the intermontane West to Mexico and through Mexico to South America. The Hudsonian Godwit, which in autumn flies east from Alaska and uses the Atlantic Flyway, in spring arrives on the coast of Texas and flies north up the Central Flyway to its Arctic and sub-Arctic breeding habitat. The great flocks of Sandhill Cranes that stage on the Platte River in Nebraska use the Central Flyway in both spring and fall.

  The Pacific Flyway generally follows the West Coast from Alaska and British Columbia to Baja and southward along the Pacific coast to the Southern Hemisphere. This route is used by Arctic Terns, which breed in Alaska and winter on sub-Antarctic islands south of Chile, a one-way journey in excess of twelve thousand miles. Vast flocks of geese and other waterfowl travel the route to reach wintering grounds in the interior of California and Mexico. Together the four major flyways define the North American bird migration system and exemplify the sheer diversity of the migratory habit in our birdlife.

  AUDUBON ALONG THE SOUTHERN MISSISSIPPI

  On my first morning in Saint Francisville, I am awakened early by the songs of Summer Tanager, Orchard Oriole, and Great Crested Flycatcher from the oak canopy. I rise and travel the low-country road to Cat Island National Wildlife Refuge, down on the Mississippi. In the bottomland woods I hear the voices of several passage migrants—Nashville, Black-throated Green, and Chestnut-sided Warblers—in counterpoint to the song of commonplace local breeders such as the Carolina Wren, Tufted Titmouse, and Northern Cardinal.

  Chestnut-sided Warbler

  The verdant bottomland forest of the refuge sheltered singing Kentucky and Prothonotary Warblers, two more of my quest birds, on their breeding territories. The Kentucky has a song reminiscent of the Carolina Wren’s, but fuller and less complex. This powerful songster is olive above and bright yellow below, with a drooping black ear streak. This is a true denizen of the deep-forest interior, its breeding range entirely confined to the eastern United States. It winters south to Colombia and Venezuela. Whereas the Kentucky was difficult to spot in the forest, the Prothonotary—the golden swamp warbler—was a flash of orange-burnished yellow with blue-gray wings, often in full view on a prominent perch. Its monotonous swit swit swit swit swit swit signaled the presence of a swamp, for this species nests only in trees standing in swamp water—something Cat Island National Wildlife Refuge has plenty of. Because of its strong affinity for swamplands, the Prothonotary is especially common in the Deep South. It winters as far south as northern South America.

  After my visit to Cat Island, I drove to downtown Saint Francisville, the most picturesque and historically preserved small town I’d seen in the Deep South. Its main residential street was lined with period bungalows painted white or a pale pastel. All were built more than a century ago, and all had been lovingly preserved: small, cozy, and set unde
r the deep shade of Live Oaks and other old trees. I took breakfast at the Birdman Café, where a resident, seeing my field guide on the table, struck up a friendly conversation about birdwatching. Such conviviality, combined with the fine architectural touches downtown, was beguiling. This was a place where it would be fine to retire—or at least spend the winter.

  Afterward I drove back to the campground and bicycled to the Audubon State Historic Site at Oakley Plantation. John James Audubon, who arrived here from New Orleans on June 18, 1821, as an aspiring bird artist, wrote of the site: “The rich magnolias covered with fragrant blossoms, the holly, the beech, the tall yellow poplar, the hilly ground and even the red clay, all excited my admiration.” A long entrance drive passed through a mix of grand old-growth pines and towering hardwoods, with Live Oaks and Loblolly Pines prominent among the ancient trees. Greeting me was a morning chorus of breeding birds from the canopy as well as from the thick understory set back from the drive—Kentucky Warbler, Summer Tanager, Great Crested Flycatcher, Wood Thrush, Red-shouldered Hawk, Yellow-billed Cuckoo, and Red-headed and Pileated Woodpeckers were all in voice. I stopped several times to revel in the symphony of spring at this wondrous intersection of ornithology, landscape, history, architecture, and art.