INTERTIDAL RESULTS 

 Sedimentary Environment 



The JC station is a semi -protected, southeasterly facing beach that is seasonally exposed to waves 

 produced by southeast winds (primarily during fall and winter storms). The sediment at this station is 

 composed of medium to very coarse sands; mean grain size since March 1979 ranged from 0.3 - 1.3 

 mm (I'ig. 2). These sediments generally contain only 1-3% silt/clay and large amounts of eelgrass 

 {Zoslera marina) and algae often cover the beach. The beaches at GN and WP face southerly and are 

 exposed to the prevalent south to southwesterly winds which occur in the Millstone area. Wave scour 

 produces clean, sandy beaches composed of medium sand which ranged from 0.3 to 0.8 mm in sb,e 

 since 1980; silt/clay content at these stations has been consistently low (< 1%). 



During the monitoring period, temporal fluctuations in sediment grain size and the percentage of 

 silt/clay have been characteristic of the JC station and possibly reflect the more seasonal nature of 

 erosion and accretion cycles. In contrast to JC, sedimentary characteristics of the GN and WP beaches 

 have exhibited temporal stability, both seasonally and annually and is probably due to more uniform 

 exposure to wave induced scour. 



General Community Composition 



I'he 720 samples collected at the three intertidal beaches during the baseline period yielded 135 

 taxa and 69,448 individuals. Since 1980, communities have been dominated by polychaetes and 

 oligochaetes, which frequently accounted for over 75% of the total number of individuals collected 

 annually (Table 2). The JC community was dominated by the oligochaetes, which accounted for 40-86% 

 of the individuals collected in each of the last six years. At GN and WP, polychaetes were generally 

 most abundant and oligochaetes accounted for less than 40% of the individuals. At these stations, 

 rhynchocoels were often an abundant component of the community. In terms of species number, 

 polychaetes were most numerous and, although arthropod and mollusc species were present at JC and 

 GN, these groups accounted for less than 5% of the total individuals collected. 



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