Myriad flickering darts of white – a mass of terns pendulums with and against the wind. Their querulous voices are barely audible over the noisome sea and the lowest members of the flock are just visible through the humid ocean air. They sketch gloriously complex aerial motifs, present in movement only and gone with the flashing passage of light. A blizzard of birds smothers the coastline and blurs the outline of the lagoon.
At the southern end of Noordhoek Beach, where the Wildevloelvlei wetland complex sometimes drains into the sea, there is a surprisingly remote, often windswept place. Usually featuring a shallow tidal lagoon set in the back of a broad, white expanse of open beach, this is a popular spot with the region’s coastal and freshwater birds. It provides lucrative opportunities for wading species to forage in the thin, clear layer of brackish water, and offers acres of safe space for waterbirds of many kinds to roost in relative safety and with minimal disturbance.
Just recently, this already special spot has been central to the lives of a large aggregation of long-distance visitors. A huge flock of mostly Common Terns (but including a few Sandwich Terns, and probably a good number of Arctic Terns too) has been resting up along the fringes of the lagoon, in between feeding flights out along the coast. Just how many birds make up this gathering is beyond my reckoning, but at its height, when most individuals are land-based, it must run to the 10s of thousands. As is often the case with large flocks of birds, the terns are skittish and prone to fright, regularly bursting skyward as a single, fluid entity and surging, amoeba-like, back and forth over the shore. The nature of these highly coordinated flights parallels the balletic ‘murmurations’ famously performed by mega-flocks of Common Starlings. Some of the flushes seem to be false alarms, presumably prompted by twitchy terns spreading panic through the crowd. Others are clearly caused by people and their dogs, either wandering a little too close as they traipse along the beach, or heading straight through the throng of anxious birds to cause a stressful bout of chaotic mayhem.
The remarkable spectacle of this roost is a very welcome addition to the range of other avian treats more routinely observed at this special site. For example, a significant number of African (Black) Oystercatcher pairs breeds here every summer. Right now, many are feeding well-grown chicks, running an exhausting shuttle service between the back of the beach and the waterline, their bright, piping calls marking time with the turning tide. Dishevelled parents prize mussels and polychaete worms from exposed rocks along the southern shore and flap them hastily back to broods of sooty ingrates, waiting impatiently somewhere out in the desert of sand between the strandline and the lagoon.
In a similar scenario, a small population of Swift Terns is ferrying small fish to fledged young stationed just behind the crest of the beach. As they fly overhead their strident calls add a brittle, cutting edge to the complex symphony of marine sounds, while their seductively clean and slender lines add an exotic elegance. Also, there are small numbers of Pied Avocet and Black-winged Stilt, sleeping one-legged in the deep or stalking the shallows of the lagoon, heavy-billed adult Caspian Terns out on patrol with dependent juveniles trailing plaintively in their wake, and hordes of Kelp and Hartlaub’s Gulls of all ages, engaged in a multitude of nefarious activities.
Star-shaped footprints festoon the sand, punctuated by the washed-out stains of avian pollution and the occasional moulted feather, caught on a drift of dried seaweed and gently quivering in the breeze. The sights, sounds and signs of birds are everywhere.
Then, like a boldly billowing cloud of confetti, they settle again as the ceremony ends, at once crowding together and jostling for space on the shiny, wet sand.