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 email@example.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.