«*- Hydrotd* 



Tunicate* o? Sea Squirt* 



Door Plate* 



A Food- Rali* Leoa 



LIFt CYCLE OF ACOHN BARNACLE 



>- Shell Wall 



■ »•«. >— rtneii wan , 'i 



Stoma* h 

 Baa* 



Naupllus Cement- T^S^Z 



J -Mittiti 



ANATUMV OF THE ADULT ACORN BARNACLi 



Adult Barnacle 



Figure 1.2 The marine hitchhikers. Depicted are examples of the animals 

 and plants that grow on underwater surfaces such as ship hulls — resulting 

 in marine biofouling. Ships are most susceptible to fouling when they are 

 in port. How sedentary marine organisms are transported to colonize new 

 surfaces is illustrated by the life cycle of the acorn barnacle at the 

 bottom left: 1) free-swimming larvae must attach to a substrate in order 

 to develop and feed. If they do not attach, they will die in a matter of 

 days; 2) the larvae produce a strong, long-lasting adhesive for attaching 

 themselves to substrates; 3) the larvae attaches head first, forming a 

 conelike shell around itself, and uses its feet to propel food into its 

 mouth. The anatomy of the resulting adult is shown at the bottom right. 

 From a drawing by Lisa Haderlie Baker, courtesy of the National Science 

 Teachers Association, the Carolina Biological Supply Company, and OCEANUS, 

 the International Magazine of Marine Science and Policy. 



1-4 



