On this warm, sunny afternoon along the Front Range, my wife and I took a walk around Harriman Lake, in southwest Metro Denver. Dammed at its west end and bordered by marsh along its eastern half, the lake always attracts an interesting mix of water birds.
Now that most winter residents have departed for their more northern breeding grounds, waterfowl were represented primarily by American coot, mallards, double-crested cormorants and a few pied-billed grebes; a couple of great blue herons also stalked the shallows. Of most interest was a flock of eight western grebes, diving for fish in the center of the lake. Having wintered on coastal bays of Southern California and Mexico or on lakes of the Desert Southwest, these gregarious birds return to the Great Basin and surrounding States to breed. Colonial nest sites are established in the marshy shallows of ponds and lakes, where platforms of aquatic vegetation are attached to the reeds. Once hatched, the chicks will ride on their parents' backs until able to fend for themselves.
Though not observed this afternoon, the western grebes will soon engage in their courtship behavior, racing across the surface of the lake in an upright posture while carrying a piece of nest material in their bill. Those of us fortunate to have observed this seasonal dance know that it is one of the more distinctive and memorable avian displays on our planet.
