Winds of Change
By Larry Bozka
Hurricane Claudette did some good as well as some bad for coastal habitat.
When Hurricane Claudette visited the middle Texas coast early on the morning of July 15, she left plenty of calling cards: sand dunes razed flat by towering blades of breaking surf, shrimp boats and cruisers ripped from their moorings and hammered into bulkheads, downed power lines that left more than 74,000 people without electricity. Claudette shredded roofs, overturned cars and uprooted and mangled countless trees. Although only a Category 1 hurricane, the lowest on the Saffir-Simpson scale of strength, Claudette nonetheless inflicted some $30 million in damages.
Wildlife paid a price, too. Almost center-punched by the eye of the storm, the burgeoning shorebird rookery on Bird Island in East Matagorda Bay was substantially damaged. Juvenile brown pelicans and laughing gulls soon washed up along the banks of the Intracoastal Waterway near Lone Oak Bayou at Chinquapin, on the bay’s upper tier. Some of the juvenile pelicans were captured and taken to a wildlife rehabilitation specialist in Bay City; for others, it was too late.
Yet, difficult as it is for some to fathom — particularly coastal residents who have witnessed the brutally random consequences of storm surge and wind — hurricanes and tropical storms can play positive roles in the saltwater ecosystem. Coastal terrain is invariably rearranged to some degree, particularly inside water-exchanging tidal passes and shoreline cuts. Channels are deepened and cuts are opened, if only temporarily. Around the Matagorda Bay complex, Claudette’s landscaping work was immediately noticeable.
“A narrow, shallow pass, which opened Redfish Lake at Carancahua Bay to West Matagorda Bay, was widened by Claudette’s storm surge,” says TPWD Matagorda ecosystem leader Bill Balboa of Palacios. “More than likely, the wider pass will stay open and could continue to scour and get deeper. A consequence of the storm-altered pass was the loss of seagrasses along the south shoreline of Redfish Lake near the pass. Increased turbidity in Redfish Lake, resulting from the wider pass, may delay or prevent regrowth of seagrasses for quite some time.
“On the positive side,” Balboa adds, “the exchange of water could help circulation into Carancahua Bay. If this pass continues to deepen and grow wider, the increased water exchange should benefit everything from nutrients to predator fish.”
Balboa expected the storm to open up Brown Cedar Cut on the far end of East Matagorda Bay near Sargent. However, true to the unpredictable nature of hurricanes at work, Claudette instead carved open Three-Mile Cut, (three miles, of course) east of the Matagorda jetties at the mouth of the Colorado River.
Fishermen enjoyed excellent action in the rejuvenated lagoon for several weeks afterward. Red drum, whiting and other beachfront species ventured into the remote little estuary with each passing tide. The diminutive pass has since silted in, but local anglers continue to capitalize on the literal sport fishing windfall.
Farther up the coast, at San Luis Pass between Galveston and Freeport, Claudette significantly deepened the eastside channel of the mile-wide natural pass between West Galveston Bay and the open Gulf.
“Storms like this help maintain the freshwater-to-saltwater gradient, regenerate the nutrients and in turn, the entire food chain,” explains TPWD Galveston Bay ecosystem leader Rebecca Hensley. “All of the ecosystems and estuaries are affected. Storm surge and high tides flush into areas that don’t normally get saltwater intrusion. Simultaneously, with the rainfall, a lot of nutrients become available and essentially restart the estuarine process.”
Hensley notes that Claudette carried relatively little rain, especially compared to the prolonged torrential downpours that accompanied Tropical Storm Allison in June 2001. Allison’s “black water” effect subsequently killed large numbers of fish on the upper Texas Coast.
Black water occurs when salt water is pushed deep into coastal estuaries and then retained by a fresh overlying cap of rainfall. Prolonged saltwater saturation kills or “burns” much of the inundated vegetation. As the grass decomposes and bacteria thrive, oxygen content is drastically reduced. Although some red drum and flounder in the Intracoastal Waterway near Cedar Lakes Creek west of the San Bernard River were affected, the fish kills were isolated.
“We also didn’t see much freshwater runoff that could potentially pollute the bays,” Hensley adds. “The timing of the rain should actually help the life cycle of marine life in the marshes, especially shrimp and crabs. Reduced salinity also helps reduce natural predation on oysters.”