Hitting Us Where it Hurts: The Untold Story of Harmful Algal Blooms

To view the original story map, please see version on the ESRI website, "Hitting us where it hurts: The untold story of harmful algal blooms."

Without algae, you would struggle to breathe.

Algae produce most of the oxygen we breathe and provide food for fish and other animals. They are the foundation of ecosystems.

Algae, however, are not always good.

They can bloom in excess and produce toxic compounds that are harmful.

Harmful algae can contaminate seafood and drinking water with toxins, make humans and marine wildlife very sick, slow tourism, damage the environment, and kill fish.

Harmful algal blooms cost us a lot of money.

Harmful algal blooms cost the U.S. economy millions of dollars each year.

Explore events below to learn how they erode seafood competitiveness and disrupt the U.S. economy.

View reference list for information in this map (PDF, 4 pages). Monetary values are reported in 2014 dollars unless otherwise noted.

1. $97.5 million in lost Dungeness crab landings and estimated $40 million in lost tourism spending in 2015: On the U.S. West Coast (California, Oregon and Washington), a toxic bloom of Pseudo-nitzschia shut down the Dungeness crab and razor clam fisheries in 2015. The commercial Dungeness crab fishery lost $97.5 million in landings compared to the previous year. Coastal communities in Washington lost an estimated $40 million in tourism spending. Values reported in 2015 dollars.
2. Over $10 million estimated in lost shoreline property value services and 500,000 residents could not drink the city's tap water in 2014: In Toledo, Ohio, 500,000 residents were advised to stop drinking tap water for 3 days due to high levels of microcystin, a toxin from cyanobacteria that was found in a city water treatment plant. Additionally, an economic study estimated that this bloom led to losses of $10.05 million in shoreline property value services (i.e. drinking water, recreation, wildlife habitat, etc.). Values are reported in 2015 dollars.
3. 277 manatee deaths in 2013: In Florida, 277 manatee deaths were attributed to or suspected to be caused by a red tide of Karenia brevis in 2013. In Florida, manatees are a threatened species under the Endangered Species Act. Because manatees die nearly every year from exposure to red tides, these deaths are factored into species management plans.
4. Up to $5.58 million in estimated lost fishing expenditures: For counties adjacent to Lake Erie, researchers estimate that large, summer-long blooms of cyanobacteria would lead to a decrease of approximately 3,600 fewer fishing licenses issued and approximately $2.25-5.58 million in lost fishing expenditures. Estimates were based on algae levels and fishing license sales from 2011- 2014.
5. $10.3 million drop in oyster landings in 2011: In Texas, oyster harvesting was banned for 3 months of the 6-month season due to a red tide of Karenia brevis in 2011. The Texas Parks and Wildlife Department estimated that oyster landings dropped by $10.3 million compared to the previous year.
6. 2,000 square miles covered by a toxic algal bloom in 2011: In Lake Erie, a toxic bloom of cyanobacteria covered more than 2,000 square miles in 2011. The bloom was more than three times larger than any of the previously documented blooms and contributed to an expanding dead zone, reduced fish populations, fouled beaches, and slowed a multi-billion-dollar tourism industry.
7. $235-470 million potential loss to local economy in 2011: In the Indian River Lagoon, Florida, a "super bloom" in 2011 resulted in a 60% loss of seagrass coverage due to shading. Brown tides the following year prevented seagrasses from recovering. Scientists estimate that seagrass may contribute from $5,000-10,000 per acre per year to the local economy, meaning that the 2011 seagrass loss represents a potential reduction of $235-470 million for each year it is absent.
8. $5 million in fisheries failure disaster relief in 2009: In Massachusetts, Maine, and New Hampshire, a fisheries failure was declared by the Commerce Secretary because of shellfish harvesting closures due to red tides of Alexandrium in 2009. $5 million in funds were appropriated and allocated to the three states to improve monitoring and early warning for harmful algal blooms and to mitigate impacts on the fishing industry.
9. $4 million in fisheries failure disaster relief in 2006: In Massachusetts and Maine, a fisheries failure was declared by the Commerce Secretary because of shellfish harvesting closures due to red tides of Alexandrium in 2006. $4 million was appropriated and allocated to the two states to improve monitoring and early warning for harmful algal blooms and to mitigate impacts on the fishing industry.
10. 179 threatened loggerhead sea turtles died in 2005-2006: On the Florida Gulf Coast, a persistent and extensive red tide of Karenia brevis caused the deaths of 109 threatened loggerhead sea turtles in 2005 and 70 in 2006.
11. Almost $50 million in lost income in 2005: In Maine, red tides of Alexandrium and floods in 2005 resulted in $7.2 million in losses for harvesters of soft-shell clams, mahogany quahogs, and mussels. Accounting for the indirect and induced effects on Maine businesses and residents, the total impact was estimated at $17.7 million in lost sales and $49.46 million in lost income.
12. Over $785,000 in red tide clean-up and response costs from 2004-2007: Four Florida counties (Pinellas, Sarasota, Lee, and Collier) and two municipalities (Longboat Key and Naples) reported clean-up and response costs specific to red tides of Karenia brevis of $785,707 from 2004-2007. Costs included initial assessment, public notification, and removal of dead fish from beaches.
13. Over $785,000 in red tide clean-up and response costs from 2004-2007: Four Florida counties (Pinellas, Sarasota, Lee, and Collier) and two municipalities (Longboat Key and Naples) reported clean-up and response costs specific to red tides of Karenia brevis of $785,707 from 2004-2007. Costs included initial assessment, public notification, and removal of dead fish from beaches.
14. 2,239 marine mammals stranded in 2002: In southern California, 2,239 marine mammals (primarily California sea lions and long-beaked common dolphins) were stranded in 2002. Some of the animals showed severe neurologic signs. Intoxication with a toxin produced by blooms of Pseudo-nitzschia was suspected to be the cause.
15. Up to $4.4 million in emergency room visits in 2001-2002: In one hospital in Sarasota County, Florida, emergency room visits due to respiratory illness increased by 54% during red tides of Karenia brevis in 2001-2002. The costs of these respiratory illness-related emergency room visits in Sarasota County alone range from $0.54 to $4.4 M, depending on the bloom severity and duration.
16. $3.7 million (2001) and $1.4 million (2003) in total economic impacts to tourism and recreation: In Possum Kingdom Lake, southeast Texas, golden algal blooms cause fish kills and unsightly foam, reducing recreational fishing. The total economic impact to tourism and recreation for three counties surrounding the lake was estimated to be $3.7 million from January to July, 2001 and $1.4 million from January to April, 2003.
17. Up to $96 million in lost consumer surplus in 2001: In Delaware, Maryland, North Carolina, and Virginia, consumers in coastal areas were surveyed about their willingness to pay for seafood after fish kills caused by Pfiesteria in 2001. The lost consumer surplus was between $50-96 million in the month following the fish kill.
18. $22-25.4 million in total economic impact in 2000: In Galveston County, Texas, it is estimated that the direct economic impacts of a red tide of Karenia brevis in 2000 were between $13.6-15.8 million. Total economic impacts were estimated at $21.3-24.6 million in this county alone, due to commercial oyster fishery closures, lost tourism, and costs of beach clean-up.
19. $20.42 million in estimated lost spending by recreational razor clammers for a full season closure: On the Washington coast, a full season closure of the recreational razor clam fishery due to toxic blooms of Pseudo-nitzschia is estimated to result in $20.40 million in lost tourism spending.
20. $868-3,734 reductions in daily sales during red tides from 1998-2005: In southwest Florida, three beachside restaurants experienced $868-3,734 (13-15%) reductions in daily sales when red tides of Karenia brevis were present from 1998-2005.
21. $81 million in lost seafood sales in 1998: In Maryland, Delaware, Virginia, and North Carolina, fish kills in 1998 that were attributed to Pfiesteria caused concern for human health, resulting in an estimated $81 million in lost seafood sales in Maryland alone.
22. $1.1 million in lost value for geoduck in 1998: In southeast Alaska, toxic blooms of Alexandrium in 1998 contaminated geoduck and prevented them from being sold live or whole. The shellfish had to be processed to remove the toxic parts. Processed meat brings a lower price, causing a $1.1 million loss in value.
23. Over 400 California sea lions died in 1998: In the Monterey Bay region, a harmful algal bloom was observed from May to June 1998. The harmful algal bloom produced a neurotoxin that was detected in small fish and in sea lion body fluids in the region in the same time period. 400 California sea lions died and many others displayed signs of neurological dysfunction. Annual sea lion mortalities due to domoic acid poisoning have continued, with some years being much worse than others.
24. $1.56 million in small business loans due to red tide disaster declarations in 1996, 1999, 2001 and 2002: In southwest Florida, red tide disaster declarations in 1996, 1999, 2001 and 2002 resulted in 36 small business administration loans for a total of $1.56 million. Loans were administered under the Small Business Administration Reauthorization and Amendments Act of 1998.
25. $4.1 million (restaurant) and $5.4 million (lodging) in monthly reduced revenues during months with red tides from 1995-1999: In Fort Walton Beach and Destin, Florida, red tides of Karenia brevis reduced restaurant and lodging revenues by $4.1 million and $5.4 million per month, respectively, which represents a 29% to 35% decline in average monthly revenues, during months of red tide incidence from 1995-1999.
26. Up to $856,330 in lost value for Dungeness crab in 1992: In southeast Alaska, toxic blooms of Alexandrium in 1992 prevented Dungeness crab from being sold whole, live, or cooked. Crab had to be sectioned to remove the toxic parts. Sectioned crab bring a lower price, causing a $694,431-856,330 loss in value.
27. $2.7 million in small business loans due to red tide declaration in 1988: In North Carolina, a disaster declaration due to a red tide of Karenia brevis in 1988 resulted in 51 small business administration loans totaling $2.7 million. Loans were administered under the Small Business Administration Reauthorization and Amendments Act of 1998.
28. $48.8 million loss of revenue and 48 people sickened in 1987-1988: In North Carolina, a red tide of Karenia brevis caused 48 people to become sick with neurotoxic shellfish poisoning and closed shellfish harvests, resulting in a $4.7 million reduction in clam landings and $48.8 million loss of revenue to a North Carolina coastal community.
29. $2-6 million loss to mariculture industry: In Puget Sound, Washington and also British Columbia, Canada, recurring blooms of Heterosigma have caused extensive damage ($2-6 million/event) to wild and net-penned (mostly salmon) fish industry.
30. $4.5 million in annual economic losses to bay scallop fishery in 1985 and 1986: In Long Island Sound, New York, brown tides decimated bay scallops in 1985 and 1986. Preliminary estimates of annual economic losses to the bay scallop fishery were $4.5 million.
31. 34 million fish killed, valued at $14 million from 1981-2008: In Texas, 33 water bodies have been affected by golden algae with losses conservatively
32. $1.79 million loss to commercial oyster industry in 1980: In California, a toxic bloom of Alexandrium in 1980 made nearly 100 people sick with paralytic shellfish poisoning after eating contaminated seafood and led to two deaths. Oyster harvests were banned for 30 days, leading to a total economic loss of $1.79 million to the commercial oyster industry on the West Coast.
33. Landings of hard clams and harvesting licenses plummeted in 1970s and 1980s: In Long Island bays in New York, commercial landings of hard clams and commercial and recreational harvesting licenses plummeted between the 1970's and 1980's, due to both overfishing and brown tides.
34. 60% increase in Ciguatera Fish Poisoning (CFP) between 1973-1983 and 1998-2008: In Pacific Island Countries and Territories, human cases of CFP reported to local governments increased from 104 cases per 100,000 people in 1973-1983 to 194 cases per 100,000 people in 1998-2008. This increase raised the status of CFP to an acute and chronic illness with major public health significance.
35. $71 million in estimated losses to tourism industry in 1974: On Florida coasts, red tides of Karenia brevis led to decreased hotel and motel occupancies from January to March in 1974. Losses to the tourism industry in seven Gulf Coast counties were estimated at $71 million.
36. $107 million in estimated losses to tourism industry in 1971: On Florida coasts, red tides of Karenia brevis led to decreased hotel and motel occupancies. Losses to the tourism industry in seven Gulf Coast counties over a 50-day period were estimated at $107 million. Beach cleanup costs and losses to the fishing industry were estimated to be another $8.7 million.
37. Over $2 million in estimated economic losses if 67 Lake Erie beaches were closed for just one day: For 67 Lake Erie beaches, researchers estimated that aggregate economic losses from closures could exceed $2.39 million per day. These are hypothetical estimates, based on the losses experienced by people from Michigan, Ohio, and Indiana when they are unable to make recreational trips to closed beaches. Values are reported in 2015 dollars.
38. Up to $2,025 estimated increase in price per home when algal levels were reduced: For homes near Lake Erie, researchers found that when a proxy for harmful blooms of cyanobacteria (chlorophyll-a) was reduced by 1 microgram per liter, home prices increased by 2%. Thus, with a median home price of $92,500 in this area, home prices can increase from $1,757-2,025 each. Prices are reported in nominal dollars (2002 to 2011) and year fixed effects.
39. Algal bloom clean-up programs cost condominiums $55,000 annually: On the island of Maui, Hawaii, macroalgal blooms are a recurring problem that adversely impact coral reefs and local aesthetics. Major condominium properties have utilized privately funded beach clean-up programs for years, incurring costs of $55,000 annually. Costs are reported in 2001 dollars.

Harmful algal blooms are getting worse.

Before 1972, we saw fewer types of harmful algal blooms and they were less frequent.

Today we see more types of harmful algal blooms. They occur more often, last longer, and have spread to new places.

Harmful algal blooms put people out of work.

In 2015, the largest harmful algal bloom ever recorded in the region struck the U.S. West Coast.

The bloom produced record-breaking toxin levels, shutting down the Dungeness crab and razor clam fisheries for many weeks.

Fisheries closures kept seafood safe for consumers, but cut off access to important fisheries resources that many families depend on.

2015: An unprecedented bloom

Dungeness crab is the most lucrative fishery on the U.S. West Coast.

In 2015, the commercial Dungeness crab fishery lost $97 million in landings compared to the previous year. The commercial fishery failures resulted in disaster declarations.

Razor clams draw tens of thousands of recreational clam diggers to U.S. West Coast communities.

In 2015, Washington State's coastal communities lost approximately $40 million in tourism spending.

Fisheries closures lead to economic losses that affect many sectors of society

Fisheries closures meant that commercial and recreational fishers could not harvest from the sea.

Seafood processors and markets had no product to process and sell.

Without razor clam openers to draw visitors to the coast, coastal restaurants, hotels, and stores experienced lower patronage.

Hear first-hand accounts of how harmful algal blooms impact workers.

Andrew Evanow, Commercial Fisherman (Crescent City, California)

Tania Miller, Restaurant Manager (Long Beach, Washington)

What are we doing about these natural disasters?

NOAA uses satellites and state-of-the art ocean sensors to provide early warning of harmful algal blooms nationwide.

Similar to weather forecasts, this information is used to develop harmful algal bloom forecasts to predict when and where they may cause harm.

NOAA's research investments make this service possible and improve forecast accuracy.

Government agencies use these early warnings to prepare communities and protect local economies.

"Gotta love that green light on the top of your bulletin! Our planned opening of the Washington recreational razor clam fishery can proceed safely and without concern over HABs...it would not be an exaggeration to expect as many as 40,000 people visiting the coast to dig razor clams during the course of this opener. Those visitors could spend as much as $3.6 M in Washington's small coastal beach communities." -Dan Ayres, WA State Coastal Shellfish Manager, Spring 2018

Just as NOAA helps communities prepare for severe weather and tsunamis, NOAA researchers are working to prepare communities for harmful algal blooms.

By tracking and understanding how harmful algal blooms impact communities, researchers are helping to identify ways to help them cope with these disasters.