1. Smithsonian Environmental Research Center (SERC), 647 Contees Wharf Rd. P.O. Box 28, Edgewater, Maryland 21037-0028 USA
2. Marine Science Institute, University of Texas at Austin, 750 Channel View Dr., Port Aransas, Texas 78373 USA
3. Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, Alabama 36849-5407 USA