by M. Kathy Raines Suddenly, from a tranquil ocean of grasses and brush, explodes an astonishing athlete—a low-cruising, long-winged harrier that deftly weaves under, over and through foliage, its yellowish-brown hues dazzling in the sunlight. With this element of surprise, no wonder it’s dubbed “the gray ghost.”  This engaging winter guest, the northern harrier (Circus…