The Ecological Niche of Anthopleura elegantissima at Race Rocks
by: Santiago Salinas, January 2000.
“The field work consisted of taking three variables (elevation, rock temperature and time underwater) and testing them against number of organisms. Three different populations were selected and a transect containing subsequent quadrats for each was used (a Mann-Whitney test was performed to determine whether or not there is a general trend between the three populations). The variables were selected because they are known to be influential in the determination of the distribution of species. Since the field work took place during only one day due to the limiting factor of low tide level, a good and thorough design was created. The priorities were the elevation of the terrain and the number of organisms per quadrat in view of the fact that the tidal level was constantly altering, making the measurements inaccurate otherwise. The rock temperature was taken once these two sets of values had been gathered from the three locations.”
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