One of the noisier recent returns to Wisconsin, the killdeer at Faville Grove mark the early March skies with “peeps” and “peep-lo’s” and general boisterousness. Amid winter’s solitude, the trills of red-bellied woodpeckers and the chirps of chickadees break the silence with sometimes jarring effect. A landscape blanketed in snow pares down the soundscape to a minimum—trees croaking and aching, remnant leaves rustling, and hints of where sounds were; animal tracks from things long gone but now reconstructed in the mind as the playful coyote and the frolicking otter.
Killdeer join the dam of sound on a jailbreak on these warm March days. They may be overlooked for the waterfowl, red-winged blackbirds, and cranes, but the killdeer (Charadrius vociferous) lives up to its Latin name and brings its own vociferousness.
With a voice that carries, the killdeer moves from its wintering grounds on the southern half of the continent and breeds across a swath spanning from central Mexico and the Caribbean all the way north into Alaska. Almost any open or barren spot could entice a killdeer: from parking lots to burned grasslands to edges of farm fields, the killdeer’s adaptability shows in its wide range.
Photo by Andy Reago & Chrissy McClarren
There is evidence that the killdeer continues to expand its range. In the mid-19th century, killdeer would breed only as far south as central Florida, but today killdeer range into the Florida Keys and the Caribbean. Recently, breeding pairs have turned up in Venezuela and Colombia, which is quite the departure from the typical migration pattern. The exact reason for this variation is unknown, but studies have shown that birds can rely heavily on the earth’s magnetic field to navigate during migration… perhaps these killdeer had malfunctioning compasses.
The killdeer are not the first species to start populations with an inverted migratory pattern. Barn swallows in Argentina have constructed their muddy nests among structures in Buenos Aires, and even shifted their breeding cycle to coincide with the southern hemisphere’s summer. In addition, these birds migrate north over the southern hemisphere’s winter. The killdeer, on the other hand, were still breeding during their usual time (April-July), though it is unclear where the South American residents migrate.
A recent study looking at 40,000 year-old trees from bogs in New Zealand suggests the earth’s magnetism flipped around 42,000 years ago, and over a few hundred years the poles of the earth entirely flipped as well. Who knows how confused birds were during this time. Today, we can only hope that the killdeer in Venezuela are not acting on some monstrous magnetic shift; the dozens and dozens of killdeer recently arriving at Faville Grove refute those ex-pat dissidents.
Written by Drew Harry, Faville Grove Sanctuary
Cover photo by Andy Reago & Chrissy McClarren
