17 



Figure 3-5. Abundance of Mya arenaria from Sheep Island Infaunal Cores* 



250 



1990 



1991 



1992 



1994 



1998 



*DM = Constructed Intertidal Flat REF = Reference Site 



Size frequency analysis of soft-clam populations was possible for both Sheep Island 

 sites, but only in 1991 and 1992. In 1991 the Mya population at the constructed intertidal 

 flat was smaller in size than that of the reference area; specimens in the 16-20 mm size 

 range constimted the bulk of the population (Figure 3-6). The reference area population 

 was bimodal with peaks at the 10-15 mm and 46-50 nmi size ranges. In 1992 the modal 

 size of individuals from the constructed flat population had increased with the highest 

 proportion of individuals being 21-25 mm in length (Figure 3-7). Specimens from the 

 reference area population were smaller than previous samples with most specimens being 

 in the 31-35 mm size range. Although too few animals were collected in 1998 to perform 

 size frequency analysis, over half of those found were greater than 50 mm in length 

 (Appendix 1). 



Ecological Monitoring of a Constructed Intertidal Flat at Jonesport, Maine 



