Mud flats stretched before me for what seemed like miles. Waves lapped at one far off edge, but seemed too distant to threaten the clusters of water birds milling about. I pulled my hood tight against the nipping winds and stared at the ground as I made my way down the adjacent levy. Several bundled birders were already gathered at a widened hillock where the muddy flats below tendriled into marshy meadows, cutting miniature cliffs along the front-lines. Black-headed gulls dominated the nearest plateau, fussing at one another as they jostled for nesting space in the tall grasses. I lifted my gaze beyond their antics and was shocked to note that the waves had covered half the distance from their original horizon to my new location. I watched the waves devour the flats, sending one flock then another of oystercatchers into the air. One stubborn row of birds marched just ahead of the encroaching water, resisting its claims on the land until they met another line of oystercatchers marching toward them. They faced off as if in battle, but neither side won. The troops joined in mutual retreat, escaping to the air as the water occupied the space below.
An occasional flock of black-headed gulls joined the migration from flats to inland pools behind the levy, and even more rarely a Mediterranean gull joined rank. Various species of geese and even some avocets flew overhead as well. But the true spectacle came when the water claimed the last of the muddy flats, invading the tendrils and pushing against the meadow banks. Feeding grounds vanished, thousands of red knots swarmed the sky. The waders ribboned through the air,swooshing and chirping as they banked from one side to another, swaying en mass from the disappeared mud flats to protected pools beyond the levy. It may have only lasted seconds, but it felt like minutes and energy buzzed through the air long after the last of the knots were settled.
I followed the line of local lenses that marched around the far end of the levy and into a bird hide. There the birders huddled onto a bench, cameras and telescopes braced on the sill against the head-on winds coming through the viewing window. I squeezed in, struggling to steady my own lens against the gale and grateful for the body heat coming from either side. In the pond below, the oystercatchers and knots were also huddled against the freezing gusts. The black, white and scarlet of the oystercatchers covered one hill, flanked by a collection of tan-colored knots, some gleaming sienna in their new summer plumage. A passing raptor caused frenzied flight, but mostly the birds appeared to sleep. And rest they must. The Snettisham Reserve and encompassing estuary, The Wash, is the spring staging area for migratory bird species journeying northward for nesting.
As I walked back along the levy, still glowing in awe of the clouds of birds that had flown above, a generous flock of knots lifted from the protected inland pool, crossed my path and began circling the marsh.
“That signals the start of that flock’s migration!” a local expert exclaimed.
As if on cue, the flock spread across the water and disappeared beyond the horizon.
Shouts from ahead caught our attention, “Terns!”
We looked up just in time to see a flock of terns swoop across our path and out toward the North Sea.
“Arctic terns!” my companion enthusiastically specified, “How many was that? 40? 50? That’s huge!”
The mood was electric. None of the local authorities, and aficionados they were, had ever seen such a large flock of Arctic terns on their arduous journey from their Antarctic wintering homes to their Arctic breeding grounds. These birds may fly 50,000 miles or more in a year, the longest recorded animal migration.
Time, tides and a bit of luck – it was a good day to catch spring migration at Snettisham.