Number 11
October 16, 1997
Link to NJ Fishing Consumer Alert page Link to NJ Fishing Consumer Alert page
Pfiesteria - Killer Algae or Killer Media Opportunity?

There has been a recent media onslaught centered on a microscopic, unicellular organism - technically a dinoflagellate - named Pfiesteria piscicida. This organism, proven to have caused a number of fish kills in the Chesapeake region and a complex of physical disorders in researchers and technicians working on it, is responsible for a multi-state task force, for a significant decrease in seafood sales affecting much of the Mid-Atlantic, for a number of Pfiesteria hotlines, for a tremendous amount of public concern, for  several television “specials” and for seemingly countless words giving particular, and possibly self-serving, spins to what is at this point a relatively meager amount of hard data.

Much, if not most, of the information on Pfiesteria is available through the World Wide Web. A simple Alta Vista  
[Link to Alta Vista search page] search for “Pfiesteria” yielded over 900 hits. This internet activity illustrates some of the most positive as well as negative aspects of the Web. On one hand, factual and up-to-the-minute research findings are available at the “official” sites (visit those referenced here). On the other, some sites are using the interest in Pfiesteria to contribute further to what has already been termed “Pfiesteria hysteria." 
What is known for sure about Pfiesteria piscicida? It is a single-celled organism, a dinoflagellate, with the complicated life cycle characteristic of the group. Two dozen distinct life stages, including flagellated, amoeboid and encysted, have been identified. It’s not a “new” organism. Research by the U.S. Geological Survey has shown that it has been present in Chesapeake Bay and its tributaries for at least 3,000 years (From the Infobeat/Reuters email news service - -10/08/97 - Pfiesteria goes back thousands of years).

Pfiesteria-related illnesses have been documented among researchers (particularly Dr. Joann Burkholder, the North Carolina State University researcher who has done much of the pioneering work on the organism, and her colleagues) coming in close, day-to-day contact with the organism. Whether any illnesses can be attributed to people coming in contact with the organism outside the laboratory has yet to be determined [From the University of North Carolina website Link to Pfiesteria page at University of North Carolina website].

While there has been a detectable decline in consumer confidence in locally produced seafood in the Mid-Atlantic, there has not been any indication that consuming fish or shellfish from “infected” waters is deleterious to human health. Quoting from a September 19 press release from the National Fisheries Institute, a trade association representing over 1000 companies involved in all aspects of the seafood industry, “Pfiesteria is not an infectious or contagious disease - it cannot be caught like a cold. There is no evidence that it can be passed along in the food chain, or passed from fish to human....No cases of seafood poisoning have been reported from eating fish exposed to Pfiesteria. Nor has there been evidence of tainted shellfish, oysters or crabs on the market.” (NFI contacts are Emily Holt or Pam Glass at 703-524-8881)

There has been a great deal of speculation that nutrient enrichment of the waterways, possibly from agricultural run-off, is causing the Pfiesteria blooms. This has not been proven either. (from the American Farm Bureau website at to Pfiesteria page at American Farm Bureau website]

As mentioned above, the governors of Pennsylvania, Delaware, Maryland, Virginia, West Virginia and North Carolina have formed a Task Force to provide a coordinated Pfiesteria research program (Six states join Pfiesteria summit, UPI Science News - Yahoo News - Link to UPI Science News - Yahoo News- 9/19/97). Several federal agencies, including the Geolgical Survey, the National Marine Fisheries Service, the U.S. Department of Agriculture and the Environmental Protection Agency have also been involved. A number of universities and research institutions have initiated agressive Pfiesteria research programs and several millions of dollars have been made available to support this vital research effort.

Finally, there has been a well-coordinated and effective outreach program coming from a number of institutions and agencies providing authoritative and timely information on Pfiesteria (web sites and telephone contacts are referenced on the next page). Collectively they are invaluable in gaining an understanding of an extremely complex, but by no means catastrophic, situation.

Pfiesteria is a pretty gruesome organism, but is it uniquely gruesome? 

When particular aspects of Pfiesteria’s life cycle are presented in the popular press, or even in the technical literature, they can appear to be the stuff that horror movies are made of. For example: 

“Pfiesteria piscicida has a complex life cycle that includes at least 24 flagellated, amoeboid, and encysted stages or forms. Both flagellated and amoeboid forms are known to be toxic to fish....the cyst (dormant) stages...commonly occur among the bottom muds of North Carolina’s estuaries. Amoeboid stages can be found in the water column as well as among the bottom sediments; they feed on other organisms (bacteria, algae, small animals) or on bits of fish tissues by engulfing their prey. Flagellated stages...can also engulf similar prey, but more often they feed, instead, by attaching to prey cells using a cellular extension called a peduncle and suctioning the prey contents. 

Pfiesteria often makes its living as a nontoxic predatory animal, becoming toxic when it detects enough of an ephemeral substance that live fish excrete or secrete into the surrounding water. When fish (e.g., a large school of oily fish such as Atlantic menhaden) swim into an area and linger to feed, their excreta triggers encysted cells to emerge and become toxic. Active amoeboid and flagellated cells which are present also become toxic in the presence of the fish excreta. The small cells swim toward the fish prey and, in turn, excrete potent toxins into the water which make the fish lethargic so that they tend to remain in the area. The toxins also injure the fish skin so that they lose their ability to maintain their internal salt balance. As the skin is destroyed, open bleeding sores and hemorrhaging often occurs. Once fish are incapacitated, Pfiesteria feeds on the sloughed epidermal tissue, blood, and other substances that leak from the sores. When the fish are dead, flagellated stages transform to amoeboid stages and feed on the fish remains or, alternatively, if conditions become unfavorable (e.g., sudden storm), Pfiesteria cells make protective outer coverings and sink out of the water column as dormant cyst stages. All of these changes can take place in a matter of hours.” (from the NCSU Aquatic Botany laboratory Pfiesteria piscicida homepage Link to NCSU Pfiesteria site) 

But compare this to the following description of the life cycle of the parasite Sacculina, a member of the order of crustaceans called barnacles that are usually found growing on rocks or boat bottoms delicately sifting small organisms out of the water with their feathery appendages. (The words in parantheses were added for clarity). 
”The Sacculina cypris larvae swims about for a time, eventually attaching to a suitable crab. It undergoes a dramatic metamorphosis, in which the whole trunk is discarded and a cuticular tube is formed, through which the remains of the larva gain entrance to the host (crab) body. The parasite is little more than a mass of undifferentiated cells at this stage. It migrates through the host haemocoel (body cavity) and attaches to the intestine. Root-like processes grow out, eventually extending to all parts of the (host crab’s) body while the central mass below the intestine is developing into the mantle and visceral mass of the the next molt the central mass (of the parasite) pops out of the host (crab’s) body and hangs down from the external surface, thus becoming an ectoparasite, but with an extensive system of internal roots (remaining in the host crab). For some reason, Sacculina inhibits the host reproductive system, causing the phenomenon of parasitic castration.” (Invertebrate Zoology, Paul A. Meglitsch, 1967, Oxford University Press) 

Compared to Sacculina (which, we emphasize, has absolutely no effect on the quality or the wholesomeness of crabs coming to market), Pfiesteria doesn’t seem quite so horrible or quite so unique. The world out there is filled with little beasties that, were we more familiar with them, would provide us with enough inspiration for a lifetime of bad dreams.

New Jersey FishNet is supported by the Cape May Seafood Producer’s Association, The Family and Friends of Commercial Fishermen, the Fishermen’s Dock Cooperative, Lund’s Fishery, the National Fisheries Institute and Viking Village Dock