A comparative seasonal study of two populations of Hypnea musciformis from the East and West Coasts of Florida,USA I. Growth and chemistry

Dry weight levels of the red alga Hypnea musciformis (Wulfen) Lamouroux from Atlantic and Gulf of Mexico coastal sites in florida, USA were lowest in the late winter and early spring, increasing through the summer and highest in the fall. There was a two-month lag in the Gulf coast population's dry weight pattern, indicating differing growth patterns. Chlorophyll a, phycoerythrin and phycoerythrin/chlorophyll a ratios were highest in the winter and lowest in the summer for both populations. Total pigment levels for H. musciformis from the Atlantic coast site were significantly greater than those of the Gulf coast. Protein and carbohydrate percentages were inversely related in both populations, with carbohydrate levels highest in summer and protein levels highest in winter. The Gulf coast population contained significantly more protein than the Atlantic coast plants. Carrageenan levels were highest in spring and lowest in fall, the Atlantic coast population generally had higher levels than the Gulf coast population. The differences in seasonal patterns and levels of the chemical constituents were reflected by distinct morphological characteristics for each population. The Atlantic coast population was larger, darker, more coarse in texture and possessed more crozier branch tips than the Gulf coast plants. These distinctions represent acclimitization responses that relate to habitat differences.