Effect of 'brown tide' shading on eelgrass

For the past 4 summers (1985–1988), the microalga Aureococcus anophagefferens bloomed in Long Island embayments, causing large scale perturbations in water column dynamics. The “brown tide” algal blooms brought about significant changes in the benthic community as well. The high cell densities (>109 l-1) of A. anophagefferens significantly increased light absorption in the water column (Cosper et al., 1987), and reduced the light available to plants living on the bottom of the embayments. In particular, the temperate water seagrass Zostera marina L. (eelgrass) was affected by the reduced light availability due to the “brown tide” algal blooms.

Keywords: