INTRODUCTION 



The destructive activities of marine fouling and wood-boring organisms 

 has caused coastal communities to pay a high price for their control 

 (WHOI 1952; Pritchard 1980) . Boat bottoms require coatings of expensive 

 antifouling paints or frequent scrapings. Lobstermen and dock owners 

 either have to replace their wooden traps and pilings regularly or use 

 more expensive materials which have been chemically treated. Users of 

 seawater cooling systems must chlorinate, flush with hot water, or build 

 redundant systems to maintain cooling efficiency. Therefore, industries 

 and individuals become justifiably concerned with changes in the abundances 

 of these organisms. 



Artificial substrates (exposure panels) have been used to study 

 community structure and temporal variability of fouling and wood-boring 

 organisms. A variety of materials such as glass, plexiglass, ceramic 

 tiles, asbestos cement, artificial sponges and various types of wood 

 have been used for collecting these organisms. The use of exposure 

 panels in environmental monitoring studies has increased over the years 

 because this approach, in comparison to monitoring naturally occurring 

 substrates, provides several advantages, which include: obtaining a 

 known age for the community, standardization of habitat on which to 

 collect organisms, flexibility in locating sites for sampling, which 

 depends more on the ingenuity of the investigator than the availability 

 of natural substrates, and easy method for obtaining replicate samples 

 (Cairns 1982) . 



