If you need an accessible version of this item please contact JSTOR User Support

Experimental Evidence for the Origin of Alternative Communities on Rocky Intertidal Shores

Peter S. Petraitis and Steven R. Dudgeon
Oikos
Vol. 84, No. 2 (Feb., 1999), pp. 239-245
Published by: Wiley on behalf of Nordic Society Oikos
DOI: 10.2307/3546718
Stable URL: http://www.jstor.org/stable/3546718
Page Count: 7
  • Download PDF
  • Cite this Item

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support
Experimental Evidence for the Origin of Alternative Communities on Rocky Intertidal Shores
Preview not available

Abstract

Ecological theory of alternative stable communities suggests the switch between different species assemblages occurs when environmental conditions alter species composition so that it crosses a critical threshold and enters a different basin of attraction. The theory implies that once the threshold is crossed, rates of key ecological processes, such as predation and competition, will change. This conjecture was tested on sheltered intertidal shores of New England that are dominated by either mussel (Mytilus edulis) beds or algal (Ascophyllum nodosum) stands. Twelve sets of clearings of different sizes, which mimicked effects of ice scour, were created in algal stands, and mortality of transplanted mussels was monitored. Clearings were 1, 2, 4 and 8 m in diameter. Mussel mortality due to the predatory snail Nucella lapillus declined in a step-like manner in clearings ≥ 4 m in diameter. Initial densities of the predator did not vary among experimental clearings or sites and were not correlated with mussel mortality. Mussel mortality was correlated with predatory snail densities during and at the end of the experiment. These results provide experimental evidence supporting conjectures about the switch between alternative states in ecological communities.

Page Thumbnails

  • Thumbnail: Page 
239
    239
  • Thumbnail: Page 
240
    240
  • Thumbnail: Page 
241
    241
  • Thumbnail: Page 
242
    242
  • Thumbnail: Page 
243
    243
  • Thumbnail: Page 
244
    244
  • Thumbnail: Page 
245
    245