present in the Millstone Point vicinity, and the degree of seasonal and 

 year-to-year variability in their occurrence. Additionally, a change in 

 the relative species composition at the intertidal stations, particularly 

 a decrease in the number of brown algae, would be an easily observed 

 indication of thermal incursion. 



Quantitative Collections 



Undisturbed transects - In terms of the stated objectives of the 

 Rocky Shore Survey, data from the undisturbed transects are used to 

 quantify the spatial and temporal patterns of occurrence and abundance 

 of intertidal organisms in the Millstone Point area. Additionally, 

 these species form a base-line community, against which communities in 

 other studies and in future years may be compared. 



Results of three years of percent cover measurements (from March 

 1979 through February 1982) are presented in Table 2. Each month, 339 

 quadrats are sampled: to condense this large volume of data into a more 

 clearly understandable and presentable form, some generalizations are 

 made. Each transect is divided into three zones: upper, mid, and low 

 intertidal. 



Data from all five transects at each station are pooled to generate 

 an average percent cover for each organism in each zone; then each 

 organism and substratum type is assigned to one of eight habit categories: 

 (see NUSCo 1982). 



The upper intertidal (Zone I) at most stations was dominated by 

 bare rock, at times greater than 99 percent. The ephemeral class was 

 most commonly represented by a blue-green algal turf (primarily a 

 Calothrix - Lyngbya association) that was present in winter and early 



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