RIO GRANDE VALLEY, Texas (ValleyCentral) — The largest natural lake in the Rio Grande Valley is rapidly vanishing. The 3,500-acre namesake freshwater lake at Laguna Atascosa National Wildlife Refuge in eastern Cameron County is receding daily with record-high temperatures and continuing drought.
Scattered shallow pools remain where wildlife gathers to savor life-giving water, and one shrinking oasis is home to dozens of alligator gar.
Gar periodically surface to gulp air in the tepid water. They have gills like other fish but also have a highly vascularized swim bladder that supplements gill respiration, enabling them to survive in low-oxygenated water where most fish would die of suffocation.
Five years ago in 2018 was the last time this portion of the lake dried up, and if it does not rain soon the gar will perish trapped in a diminishing puddle of muddy water where some have already died.
Low lake levels are a boon to wading birds enabling them to more easily access skinny water where small fish and other prey are congregated.
Scores of Roseate spoonbills, ibis, egrets, and other wading birds busily scour scattered shallows for sustenance before moving to the next shrinking aquatic buffet.
Periodic drought compels movement, and one late afternoon reveals a trio of young alligators marching from a disappearing pool to a new liquid sanctuary. It’s a long, lonely crawl, and a fourth little gator slowly brings up the rear, finally reaching the water and slipping in.
Soon, a family of chachalacas arrives for their evening drink, warily watching newly arrived occupants of the shrinking oasis ominously cruising by.
August is historically a dry month in the Rio Grande Valley, but early September often offers a respite. Hopefully, rainfall will soon begin filling Laguna Atascosa and that will be just in time for the annual arrival of winter waterfowl.
Meanwhile, it is going to get mighty crowded at those shrinking waterholes, and just how many young gators can stack in at one shrinking oasis?
