Ecological effects of intertidal uplifting from nuclear testing

Uplifting of a portion of an intertidal rock bench by the Milrow underground nuclear test at Amchitka Island, Alaska affected algal abundance, species composition, and zonation. Parts of the populations of 8 species died off, primarily in the Hedophyllum sessile zone, and mostly within the first 6 months after the disturbance. The center of abundance of these species shifted seaward. Fucus distichus, a species of the upper intertidal, appeared in the area and recolonized a portion of the H. sessile zone. The observations indicate that intertidal algal communities at Amchitka Island are very sensitive to positive elevation changes.Contribution No. 376 of the College of Fisheries, University of Washinton, USA. This publication is based on work performed under U.S. Atomic Energy Commission Contract AT(26-1)-171 for Battelle Memorial Institute, Columbus Laboratories.