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NSF grant – DEB10-50694. 60 months, 1/1/2011 to 12/31/2020. LTREB: Ecosystem response to climate change: role of ecological subsidies and species interactions.  Oregon State University

Pre-Emption is a term used for an expeiriment to test the effects of macrophytes on the recruitment of barnacles and mussels in the low zone.  

Sites: Fogarty CreekBoiler BayYachats BeachStrawberry HillCape BlancoRocky Point

Replicates per Site: 5
there are two plots per replicate:

  • Control: plot left as is, no removal of any biota
  • Removal: plot cleared of all algae, sessile invertebrates, and any and all matieral down to the bare rock


0.25 m2 stringed quadrat, Camera and underwater case, blue 15 cm ruler, for clearing: crowbars, putty knives, wire brushes, propane torch, oven cleaner

Setup in Field:  

The plots (50cm x 50cm) are marked with ½ lag screws in the low zone and the removal plots were scraped to bare rock using crowbars, wire brushes, and oven cleaner over several tide series.  Photographs were taken of each plot before any removal took place.  Control plots are tagged with two pink zip ties and removal with one pink tip tie.  Replicates are paired together (control and removal next to each other) whenever possible and are labeled north to south at each site with one being north and five being south.


Take a picture of each 0.25 m2 plot using a ruler as a distance proxy.  Then set down the 0.25 m2 quadrat in the plot and take a photograph of each 10cm x 10cm corner square (upper left, upper right, lower left, lower right).  TAKE CARE to make sure each photograph is in focus.  Each Spring the removal plots will be re-cleared to bare rock

The plots should be photographed monthly throughout the year.

 Once back in the lab, photographs should be relabeled (ex. 1C or 1C_UR; with the plot number and treatment first and the corner of the plot second) and put photographs into a new folder with the corresponding to the site and date in the LTREB folder under the Pre-Emption project.