Working diligently with samples in the laboratory to create a gene probe 

 useful for detecting the various forms of Pfiesteria in the environment 



that the organism sits in an unusual 

 position, one different from other 

 dinoflagellates. 



Rublee's first thoughts were that 

 he and his colleagues sequenced DNA 

 from the wrong organism. Then the 

 analytical thinking started, he says. "Is 

 the organism unique, or did we pick a 

 gene that will lead us off the track? I 

 still don't know the answer, but as I 

 continue to work with the organism I 

 feel more confident that we haven't 

 made an error in Pfiesteria % phytog- 

 eny." 



And even when he is led to 

 success or confirmation of his 

 predictions, the questioning doesn't 

 stop. 



"You get really excited for the 

 next 24 hours," Rublee says. "There's 

 a little mild euphoria, but not long 

 after that you ask, why did we get it to 

 work this time? Does it make sense 

 that it worked? How do we get it to 

 work again?" 



A Bigger Mystery to 

 Solve 



When it all works again and again 

 and the pieces fit together, Rublee's 

 understanding of Pfiesteria DNA will 

 have far-reaching implications. 



In addition to confirming 

 Pfiesteria^ presence, the probes can be 

 used to determine the dinoflagellate's 

 distribution. This may help environ- 

 mental managers devise strategies to 

 reduce Pfiesteria and subsequently fish 

 kills by controlling factors that encour- 

 age the organism's growth. 



Preventing fish kills is important, 

 but Rublee believes Pfiesteria is simply 

 a clue in a larger mystery, one that may 

 ultimately be more difficult to solve. 



The organism may have lived in 

 the shadows of our environment for 

 millennia, only now emerging in force 

 because it has been lured out by the 

 right conditions. 



"My sense at this point is that the 

 frequency of Pfiesteria-rehted fish kills 



is an indication of increased eutrophi- 

 cation of the coastal zone," Rublee 

 says. 



Eutrophic waters are those 

 marked by excessive nutrients — a 

 condition that encourages algae and 

 other organisms to grow. Among the 

 sources of these nutrients are urban 

 and agricultural runoff, human and 

 animal wastes, and industrial dis- 

 charge. All of these contributors have 

 become more prevalent in eastern 

 North Carolina in the past few 

 decades. 



"Human impacts on the coastal 

 zone are truly changing that environ- 

 ment, and sooner or later we have to 

 decide what's an acceptable impact," 

 Rublee says. He sees Pfiesteria as an 

 indicator of a stressed ecosystem, and 

 he doesn't see that stress easing 

 anytime soon. 



So until the tough issues of land 

 use and environmental trade-offs are 

 resolved, researchers such as Rublee 

 will stay hot on Pfiesteria's trail. E 



COASTWATCH 9 



