As shown in the previous section (Undisturbed Transects), the shore community is divided into three 

 zones, each dominated by a specific biota: barnacles in the high intertidal, barnacles and fucoids in the 

 mid intertidal, and Chondrus in the low intertidal. Because of different life history strategies, each com- 

 ponent recovers at a different rate. Other factors that affect rates of recolonization include degree of 

 exposure, season of denuding, and inter- and intraspecific competition (Keser and I^rson 1984). For 

 example, the high intertidal is mostly barren rock, on which ephemeral cdgae, barnacles, and snails appear 

 seasonally. Many of the ephemeral algae are opportunistic, and readily colonize (at least temporarily) 

 available space. Mobile intertidal predators repopulate cleared substrata from nearby undisturbed areas as 

 soon as food availability and weather conditions permit. Therefore, the high intertidal may appear 

 'recovered' immediately after denuding, and similar in appearance to Zone 1 of nearby undisturbed transects 

 at the end of the first barnacle set. Percent cover values for all taxa found in the recolonization transect 

 studies are presented in Appendix RS Ic. 



The mid intertidal of the local rocky shore community is dominated by a fucoid canopy over a 

 barnacle understory (Figs. 6 and 7). Recovery of these components is illustrated by plotting their abundance 

 (as percent cover) over time, compared with abundance in the undisturbed transects (controls). Figure 12 

 represents recolonization by barnacles in Zone 2 of the recolonization. transects. Following the spring 

 1979 denuding (made prior to the peak barnacle settlement period), barnacles settled heavily and, generally, 

 within two months were at least as abundant in the recolonization strips as in the control areas. The 

 exception was Giants Neck; at this station, most barnacles had already set at the time of denuding, and 

 subsequent settlement was lighter than at other stations. These barnacles grew through summer, and by 

 October 1979 barnacle coverage in the recolonization strips was as high as that in the controls. After the 

 autumn 1981 denuding (after barnacle set), barnacles were rare or absent in recolonization strips at all 

 stations until the following spring, after which their abundance paralleled that in the controls. The same 

 seasonal patterns of abundance were seen, i.e., settlement in spring, growth into summer, then decline in 

 cover in autumn and winter (cf. Undisturbed Transects section). At F'E, patterns of barnacle abundance 

 after the opening of the second cut (specifically, complete elimination in September 1984 and September 

 1985) were related to thermal incursion, and are included as part of the community changes described and 

 discussed in Appendix RS IV. 



Recovery of the Fucus population in Zone 2 of the recolonization strips, relative to that in the 

 undisturbed transects (Fig. 13), was directly related to degree of exposure, hence the amount and duration 



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