Developing Methods for Restoration of Cyanobacterial Mats on Wind-Tidal Flats

With more than half of its area consisting of wind-tidal flats, the Laguna Madre, including Boca Chica, provides the largest continuous expanse of suitable habitat in North America for tens of thousands of migrating and wintering shorebirds. While often viewed as barren and unproductive, cyanobacterial mats on these flats are nearly as productive as seagrasses and saltmarshes. Tidal flats are perhaps the most important component of the beach-tidal flat-washover pass coastal mosaic used by shorebirds because there is more space and more food there than on the beaches, especially during winter when hundreds and thousands of birds are present and foraging. Alterations of the cyanobacterial mat community and the elevations of flats as a result of physical disturbances caused by vehicles (e.g., trucks, ATVs), use of heavy equipment (e.g., backhoes, bulldozers), explosions, or gouging cause by debris moving at high speed, to name a few, may result in reduced productivity of shorebird prey, the benthic invertebrates that live on and in the flats.

This project will test methods of stabilizing and restoring elevation in the field, test methods for growing cyanobacterial mats in mesocosms in the laboratory/greenhouse; 3) combine the best methods for stabilizing and restoring elevation and growing cyanobacterial mats in a field experiment. Once the results of small-scale experiments are evaluated, the methods with the most promise will inform how both methods can be scaled up (i.e., from 10s to 100s to 1000s of square feet) for use in a pilot restoration of a 5-acre plot. Subsequent monitoring of the restored site and reference sites will help inform what can/should be defined as “success.”