In early spring, tundra-nesting Baird's sandpipers arrive from wintering grounds in South America to feed along the water's edge. They are joined by many other shorebirds, including Wilson's phalarope, a species given to the curious habit of spinning on the water to stir up aquatic insects on which it feeds. When shorebirds returning to Lake Balmorhea join the variety of overwintering species, the result is a rich and complex avian mosaic. To date, more than 100 species have been documented on the lake and along its shoreline. Bryan believes that number will rise with constant observation.
Every day there is a turnover in species and in abundance.
Unless an observer is on site at all times, we have no way of knowing accurately how dynamic migration actually is. During the summer, the lake is important to a number of breeding birds, including delicate black-necked stilts that nest on open ground near the water. Discovery of the rails came as a surprise to the experts, not only because the birds are exceedingly rare in the region, but because they are declining in places where they regularly occur. This pale, winsome little ball of a bird is a delight to watch as it scurries in spurts across sandy beaches along the Gulf Coast where it winters, or on open mudflats where it often nests. They have lost many of their breeding areas because they nest in habitat that is highly valued by humans for building sites and recreational uses.