l.illt I. feeding types, denslly (#/core) , percent contribution, and Blologlial Index Value (BIV) nl the ten m..st 

 immerUdJly abundant taxa at HlllHtone Intercldal sites during 1983. Comparable data averaged over the 

 previous three years are also Included. 



Feeding 

 Type 



1983 

 Mean 

 Density 



198 3 

 !rcent 



1980-82 

 BIV 



1.7 

 0,8 

 0.3 

 0.3 



deposit feeder. SF-suspenslon feeder. 0- 



3 years. 



Trophic Structure 



Feeding ' types of the dominant intertidal organisms were compared to 

 identify any changes in community composition reflective of changing food 

 resources. The majority of the dominant organisms at all intertidal 

 stations were deposit-feeders and most were surface deposit-feeders (Table 

 3). At GN and WP , where the coarser sediments contain lesser amounts of 

 fine materia], large burrowing deposit-feeders (e.g. Haploscoloplos spp.) 

 wore typically found among the dominants. Small, surface deposit feeding 

 oligochaetes dominated at JC , presumably reflecting the increased 

 availability of fine organic material that could be used as a food source. 

 Ci'.rnivores (primarily rhynchocoels) were primarily abundant at only GN and 

 V.T. 



14 



