Crecimiento estacional de Sargassum horridum (Setchell y Gardner) Phaeophyta, en la Bahía de La Paz, B.C.S., México

Abstract

A two year study of the growth of S. horridum was done at three sites in Bahía de La Paz. They were along the Malecon in the city of La Paz, at San Juan de la Costa, and at Calerita. The growth patterns throughout each area were similar. The rate of growth was 29.5 cm/month at the Malecon in La Paz and 60 cm/month at San Juan de la Costa, recorded in February-March at each site. It was 21 cm/month at Calerita during January-February. The highest growth rate was observed during the months with the lowest water temperature (21 - 23 ° C). One month later the largest size was recorded. In 1983, the largest sizes were seen in April at the Malecon in La Paz (82 cm) and in March at both San Juan de la Costa (108 cm) and Calerita (41 cm). In 1984, the largest sizes were significantly smaller. A possible failure of the recruitment of S. horridum at Calerita is discussed. There is a significant difference in the average size found at each area. The growing pattern described is in accordance with the results of McCourt (1984; J. Exp. Mar. Biol. Ecol., 74) for tropical species. The maximum growth period is the same as found by other authors for S. sinicola in this bay, though S. horridum grows to a larger size with a higher growth rate.