Peter Cozzolino

Harmful algae are minuscule, single-celled plants that live in the worlds oceans. Most species of algae or phytoplankton are not harmful and provide as the energy producers at the foundation of the food chain. With out these microscopic organisms higher life could not exist on earth. A small number of species produce potent neurotoxins that can be transported through the food chain where they affect and often kill higher forms of life. In the past decade the number of known toxic dinoflagellates has increased from twenty-two to fifty-five. This rapid multiplication of algae that accumulates into dense visible patches near the surface of the water is called a "bloom." The common name for this bloom occurrence, when the alga contains reddish pigments, is "Red Tide." Although these blooms occur in most all waters around the world, they usually only develop in localized areas. The term, HAB, is now widely used by scientists to refer to bloom phenomenon that contain harmful toxins or cause negative impacts. (www.redtide.whoi.edu/hab/whathabs/whathabs.html)

I have focused my research on the region where the coastal waters of North Carolina are met by fresh water river discharges. Within this baud region, called the Albemarle-Pamlico estuarine system, I have done further research on the Neuse River-Estuary. In this specific region there are many different types of algae that are not causing a problem but the Pfiesteria piscicida type is the organism that has been harmfully booming. In the information to follow I hope to address (1) what the harmful algae Pfiesteria piscicida is, (2) where the blooming is occurring (3) what is thought to be causing the toxic outbreaks in the Neuse River area and elsewhere, (4) how blooms occur and what the affects are on different parts of the food web, (5) what the human health and economic problems are, (6) and what is being doe to remedy this huge environmental problem in the Neuse River area.

The harmful algae Pfiesteria piscicida (fee-STEER-ee-uh pis-kuh-SEED-uh), is a toxic dinoflagellate that appears naturally in estuaries and rivers where salt water and fresh water mix. A dinoflagellate is a microscopic, free-swimming, single-celled organism, usually classified as an alga. Most dinoflagellates are not toxic. Some are plant-like, thus they obtain most energy by photosynthesis, and others are more animal-like, obtaining most of their energy by eating other organisms. Pfiesteria is the type of dinoflagellate that is more animal-like; but because it is actually neither plant nor animal it is referred to as a "protests." The alga uses their slim whip-shaped tails, called flagella, to propel themselves. This activity is what makes Pfiesteria more animal-like; yet it is still an alga because half of the organism contains chloroplasts, which it uses for photosynthesis. When looked at under an electron micrograph Pfiesteria is approximately 7 microns wide and it has a girth of 7 thousandths of a millimeter.

Three of the hard to detect stages of Pfiesteria Algae (Pic 1)

Ever since researchers at North Carolina State University discovered Pfiesteria piscicida in1988, scientists have always found it difficult to identify this harmful alga. This is because Pfiesteria takes on many atypical forms during its life. According to the work done by researcher JoAnn Burkholder and others at North Carolina State University, "Pfiesteria assumes more than twenty different forms during its lifetime, including a difficult-to-detect cyst stage, an amoeboid stage, and a toxic vegetative (flagellated) stage, where it swims with its flagella and attacks hapless fish."(See Pic 1)

(www.mdsg.umd.edu/fish-health/pfiesteia/intro2.html) Currently the alga is being closely studied in the wild, in hopes of gaining a better ability to detect the alga in its early stages before it blooms. In laboratories the algae have been detected and studied in many different stages but currently the only way of detecting the alga in the wild is sighting massive fish kills after the bloom has already occurred.

Pfiesteria piscicida is known to occur in brackish coastal waters from the Delaware Bay to North Carolina. The organism is thought to be native to these waters and not introduced as an alien species. The organism has most likely been a common inhibitor of these waters and due to changing conditions over the years it has become more abundant. Currently this type of harmful algae has not been found in any freshwater lakes, streams, or other inland water. Other Pfiesteria-like organisms, that have not yet been named, act in the same animal-like way as Pfiesteria piscicida. These Pfiesteria-like organisms have occurred in blooms along the southeast coast from Delaware to the Gulf of Mexico. (See Diagram a)

Range of Pfiesteria

(Diagram a)

www.mdsg.umd.edu/fish-health/pfiesteia/intro2.html)

Neuse River area shown by a circle (Pic 2)

In the North Carolina area Pfiesteria has been found in high concentrations along the New River and the Albemarle-Pamlico estuarine system, which includes the Neuse and Tar-Pamlico rivers. (See Pic 2) Major Pfiesteria outbreaks have occurred in the Eastern Shore tributaries of the Chesapeake Bay, including the Chicamacomico and Manokin Rivers. In King’s Creek in Maryland and the lower Pocomoke River in Maryland and Virginia, Pfiesteria is the probable cause for thousands of killed fish in 1997. Pfiesteria is also the probable cause for a 1987 fish kill in Delaware’s Indian River. Serious Pfiesteria blooms have been detected in waters as far south as the St. John’s River in Florida.

Pfiesteria piscicida has been tracked to fish kill areas from Delaware Bay to the Gulf Coast where there are high levels of nutrients in the water. In the Neuse River and elsewhere the conditions that support an Pfiesteria outbreak are 1) warm water temperatures of about 70 degrees F, 2) High levels of Phosphorous, Ammonium (NH4), and suspended solids, 3) moderate to low salinity levels, 4) increased rainfall or runoff, and 5) the presence of fish in particularly large numbers. Massive increases in the nontoxic flagellated stage have been observed where there are phosphorous enriched waters, suggesting the organism is stimulated to multiply when brought in contact with high levels of nutrients. This is because Pfisteria feeds on algae that thrive in nutrient enriched waters. Clearly Pfiesteria is stimulated by phosphate enrichment as well as nitrate enrichment but the organism seems to respond more to phosphorous at higher levels than it does to nitrates. (Andreson p.179-188)

Specifically the reason the Neuse River is so susceptible to Pfiesteria outbreaks is because it has very high levels of nitrogen in its waters and there are massive amounts of runoff poring into the river. Assuming the Pfiesteria alga has always existed in the estuarine system; the water temperature is perfect; the large numbers of fish are present; there are low salinity levels; clearly, for years all the factors except nutrients and runoff have been in line for a bloom to occur. Waste discharge into the Neuse has increased 650% since the 1950’s. The 100 million gallons of partially treated wastewater that are dumped into the Neuse River each day operate as one of the main Pfiesteria bloom activating factors. (See Diagram b) Also because North Carolina is the second-largest hog producing state in the US and rapidly becoming number one. The hog farms surrounding the river in combination with runoff are the main source of raw waste discharges. The trees and vegetation that once served as a filter for the rivers runoff are now cut down in many areas where hog farms sit at the rivers edge. With minimal vegetation to filter runoff, increased hog wastes being discharged, and the millions of gallons of partially treated water poring into the Neuse River it is no wonder the nitrogen levels are threw the roof! In 1995,1996, and1997, American Rivers, a renowned environmental group, classified the Neuse as on of North America’s 20 most threatened rivers. (www.neuseriver.org/river_hist(1B).html)

The Neuse River

(Diagram b)

Once the factors for a Pfiesteria bloom to occur are in place and the bloom takes hold of an area, the environmental impact is huge. First the non-toxic forms of the Pfiesteria feed on the algae and bacteria in the water, along with the discharged sediments of the estuaries. In the case of the Neuse river system, its discharges are a feast for Pfiesteria in the non-toxic stage. Then Pfiesteria becomes toxic in the presence of fish, particularly schooling fish like menhaden, triggered by their excrement in the water. At this point, Pfiesteria cells changes in form and begins emitting a powerful toxin that stuns the fish, making them lethargic. Then once the fish are incapacitated the Pfiesteria feed directly on the fishes’ tissues and blood. At this point other bacteria, viruses, and fungi cause lesions and sours (See Pic 3) to develop on the open wounds of the fish. Ultimately massive amounts of fish are killed and the dead rotting fish float to the surface over time (See Pic 4). Millions of menhaden, flounder, croaker and rockfish are killed each time there is a bloom in the Neuse River alone. The magnification through the food chain is huge. Toxins are also released into the air, causing birds and surfacing mammals, such as dolphins and whales, to ingest the harmful toxins. Glenn Morris of the University of Maryland School of Medicine, who leads a team of researchers on Pfiesteria toxins, says "Unlike other toxic dinoflagellates, this species exhibits direct attack behavior towards fish and becomes toxic when it detects excreta from fish and shellfish. Pfiesteria cultures can kill healthy test fish such as scallops and striped bass in minutes." (www.seagrantnews.org/news/pfiest092298/article.html)

Pfiesteria attacked fish, dead due to the lesions and infection

(PIC 3)

FISH KILL!!!!

(Pic 4)

The effect Pfiesteria has on humans is not fatal. Moderate Human Exposure has been known to cause rapid onset of burning sensation in eyes or on skin, Red eyes, possible breathing difficulty, and possible confusion or altered memory. (www.neuseriver.org/river_hist(1B).html) Duke University scientist Ed Levin found that "rats injected with Pfiesteria display a significant learning deficit when called on to learn new tasks as long as 10 weeks later. The persistent learning impairment in rats might be analogous to the cognitive deficits humans have shown after Pfiesteria exposure." (www.ncsu.edu/seagrant/pfiest.html) In all cases the people showing any adverse affects from Pfiesteria exposure, have had rapid clearing of most all symptoms.

The Economic effects of Pfiesteria blooms in North Carolina alone are huge. Beaches close creating a drop in tourism revenues, fishing and crabbing industries suffer, and seafood sales plummet. Also due to the new laws put into action farms and water discharging industries surrounding the Neuse River have been subject to renovations thus raising the costs of their goods. Often times a hog farmer who can no meet the new discharge and runoff laws will be put out of business. An outbreak in 1987-88 closed more than 400 km of North Carolina coastline for shell fishing during the peak-harvesting season, causing economic losses estimated at $25 million.

The state of North Carolina is constantly monitoring waterways and working to protect people’s health. In areas with a history of fish kills, such as the Neuse River, warning sign have been posted advising people to stay away from the area if fish kill conditions are present. The Harmful Algal Blooms Program has been established in the Department of Health and Human Services to operate an information hotline, handle questions, and educate the public and health professionals about possible health risks from Pfiesteria exposure. For the 400 point-source discharge locations on the Neuse river, "the General Assembly made a strong response: House Bill 1339. This bill establishes a 30% reduction goal for nitrogen to be achieved within five years. Designed to achieve the 30% reduction goal set by the Legislature. This strategy equitably distributes the nitrogen reduction goal between wastewater dischargers, developers, farmers and fertilizer applicators." (http://h2o.enr.state.nc.us/nps/cheat-s3.htm) The areas along the Neuse River are being protected from harmful hog waste runoff and other nutrient discharges because of a "Riparian Area." This Riparian area is simply land adjacent to water, and it is now protected 30 feet out from the river. This means the area must be full of trees, saplings, shrubs and vines. This vegetation zone will act as a neural filter for the fertilizers and wastes that would normally just wash into the river.

New research such as river sampling is providing scientists with new data to understand how the Pfiesteria algae lives in different conditions

(Diagram 3)

Over all the Neuse River-estuary system and other Pfiesteria infected areas along the east coast have had a rough time in the past 50 years. But due to new research about Pfiesteria and other Harmful Algae blooms public awareness has risen and government officials are now getting funding to take action in places of cries, such as the Neuse River. The nutrient levels we are discharging into our oceans all over the world need to be regulated. Harmful algae do exist in our oceans naturally, but it is our own wastes and careless polluting that is the root of the problem.

Anderson, D. M., Cembella, A. D., Hallegraeff, G. M. (Eds.). (1998). Physiological Ecology of Harmful Algal Blooms. New York: Springer-Verlag.

Bushaw-Newton, K.L. and Sellner, K.G. 1999 (on-line). Harmful Algal Blooms. In: NOAA's State of the Coast Report. Silver Spring, MD: National Oceanic and Atmospheric Administration. http://state-of-coast.noaa.gov/bulletins/html/hab_14/hab.html [Accessed 10/30/00]

Kaasa, Steve. NCDENR/Division of water quality control/State of North Carolina. [Online] http://h2o.enr.state.nc.us/nps/cheat-s3.htm [Accessed 11/27/00]

Kane, Andrew. University System of Maryland/Fish Health in the Chesapeake Bay/About Pfiesteria piscicida. [Online]

www.mdsg.umd.edu/fish-health/pfiesteia/intro2.html [Accessed 11/27/00]

Lefflef, Merrill. Maryland Sea Grant College/Seafood is Safe but Uncertainty Over Pfiesteria Reamins. Sea Grant News Media Center. [Online].

www.seagrantnews.org/news/pfiest092298/article.html [Accessed 11/27/00]

National Science Foundation (NSF)/National Oceanographic and Atmospheric Administration (NOAA). The Harmful Algae Page. [Online]. Woods Hole, Woods Hole Oceanographic Institution. Available: http://www.redtide.whoi.edu/hab/whathabs/whathabs.html [Accessed 10/29/00]

Norris, Jeannie. Research Results Available on Pfiesteris Dinoflagellate/Sea Grant Press Releases: Research Results Available on Pfiesteria Dinoflagellate. [Online]. www.ncsu.edu/seagrant/pfiest.html [Accessed 11/27/00]

River History (1B)/History of the Neuse River. [Online]. www.neuseriver.org/river_hist(1B).html [Accessed 11/27/00]