Meeting Abstract

71.2  Sunday, Jan. 6  Differential accumulation of mycosporine-like amino acids in the purple sea urchin, Strongylocentrotus purpuratus, in situ GRAVEM, S.A.*; ADAMS, N.L.; Cal Poly State Univ. San Luis Obispo; Cal Poly State Univ. San Luis Obispo sgravem@gmail.com

Microhabitat variation in mycosporine-like amino acid (MAA) concentrations was studied in marine red algae and Strongylocentrotus purpuratus gonadal and epidermal tissue in the intertidal zone on California�s central coast. Algae and sea urchins were collected from four microhabitats including north-facing walls, south-facing walls, pools with sea urchins burrowed in pits, and pools with sea urchins not burrowed in pits. The total MAA concentration varied significantly among algal species (p<0.001) and there was a trend toward lower total MAA concentrations in the shady north-facing microhabitat and the microhabitat with sea urchins in pits. The gonadal tissue (both ovaries and testes) from sea urchins in pits had significantly lower total MAA concentrations (p=0.001) than those in the other three microhabitats. Gonadal concentrations of total MAAs increased from November 2006 to January 2007 (p=0.007) and were significantly higher in ovaries than in testes (p=0.008). The dominant MAA in ovaries was shinorine with a maximum absorbance of 334nm, while the dominant MAA in testes was palythine with a maximum absorbance of 320 nm, suggesting a difference in resource allocation to the gonads between males and females. Sea urchin gonadal indices decreased over time from November to January (p<0.001), were higher for males (p=0.014) and were lower in the south-facing microhabitat compared to the other three microhabitats (p<0.001). Total MAA concentration of gonadal and epidermal tissues will be compared to investigate potential trade-offs in resource allocation in adult versus reproductive tissue.