BIRDS ON THE PRESA DRYING
by
Walter L. Meagher
Photos by Wayne Colony
Ducks and waders come to San Miguel in advance of the cold and freezing temperatures that shut down their food supplies in the Upper Midwest and the Canadian Prairie Provinces; they stay on the Presa Las Colonias at El Charco until the drought of winter evaporates the pond on which they have displayed their beauty for 6-7 months. (Black-necked stilt shown on right)
The waders - Avocets and Black-necked Stilts, ballerinas of the pond - stalk prey with heads bent, stirring water with their bills, disturbing the life of aquatic invertebrates. The stilt in particular is dressed for dinner at the UN more than for hunting crustaceans. These waders feed where the presa is deepest, and their numbers diminish daily, a clock on water running out.
Where the water is most shallow, by the stone wall of the old road to Xichu, Mexican Ducks are sitting on a ‘sand’ bar. Year-round residents, they are untroubled by the presa drying. Closer to the middle of the presa are other dabblers, the Northern Shoveler and both teal - the green-winged and the blue-winged - ducks with bodies built for upending in the search for aquatic vegetation. Each kind gives a measure to water depth: dabblers feed where it is more shallow than where divers swim. (Blue-winged Teal shown on left)
Diving ducks, such as Lesser Scaup and Ruddy Duck, are built for swimming long distances under water hunting small fish. As the presa dries, they get ready to depart; but they will return next autumn.
Foonote: Presa Las Colonias is the name of the dam – you might call it a small lake; as it dries it looks more and more like a pond--in the Botanical Garden, ‘El Charco del Ingenio.’