An Update on the Benthic Algae of Mansfield Pass, Texas (Report‪)‬

Abstract - The macroalgal flora of the jetties at Mansfield Pass were examined from July 2002 to June 2003 in order to observe seasonal variations, to assess the effect of wave energy on macroalgal populations, and to compile a comprehensive species checklist. Nine sites, six on the north jetty and three on the south, were established to observe differences in the macroalgae flora with respect to time and season. Thirty-six species were collected during this study, twenty-two of which were Rhodophyta. Sixteen species are reported for the first time at Mansfield Pass. A Cheney ratio of 5.13 was calculated from this study, which indicates that the Mansfield Pass area is sub-tropical. Species richness appears to be somewhat seasonal; only sixteen of the thirty-seven benthic species were harvested year-round. Seasonality, with respect to biomass, varied monthly with a high of 21.9kg [m.sup.-2] in April 2004 and a low of 3.63kg [m.sup.-2] in October 2003. Wave energy affected the macroalgal flora as several species appeared only at those sites where wave energy was low. The macroalgae, a critical component of ecological communities in the estuaries and gulf waters of Texas, are among the least studied biological groups in the U.S. (Lehman 1999). Because of its isolation, the Mansfield Pass area has been particularly understudied, especially with regard to macroalgae. Kaldy et al. (1995) reported little or no information available regarding the Mansfield Pass jetties, their investigation being the first to report exclusively on them. They suggested that the number of macroalgal species recorded from Mansfield Pass was low in comparison to other Texas coastal jetties and a more diverse flora would be likely revealed with continued investigation.