Why Are Algae Blooms Harmful?
Certain species of Algae, such as Cyanobacteria, release toxins into the water that that they inhabit which are deadly to both animals and humans. Domoic Acid and Microcystin are two toxins released by cyanobacteria and numerous studies have found these toxins to be responsible for gastrointestinal illness, liver damage, Amnesiac shellfish poisoning, seizures, and short-term memory loss [4]. Consumption of fish from waters contaminated with HABs are primarily how humans ingest these toxins. However in certain cases, reservoirs and water bodies that have HABs and are used for drinking water often have above advisory levels of toxins [5]. Dogs and other pets post - ingestion of HAB contaminated water often deal with neurotoxin anatoxin-a poisoning which causes muscle tremors, respiratory diseases, and in severe cases, death [6]. Recently, it was also found that Cyanobacteria also produces BMAA, a neurotoxin responsible for ALS disease, Parkinson’s disease, and Alzheimer’s. These aforementioned diseases were even found to prevalent in areas surrounding HABs [7].
As algae dies and decomposes, it consumes dissolved oxygen that otherwise would have been used by aquatic wildlife. Most bodies of water can sustain this ecological process when there is a limited algae population but with excessive algae blooms, too much dissolved oxygen is consumed by the algae which results in the creation of hypoxic “dead zones”, where life cannot be sustained due to a lack of oxygen, as shown in Figure 3 [8]. Immobile aquatic wildlife such as bottom plant life and “slow moving animals” die from hypoxia, which has a ripple effect on the food web present in the body of water. Predators of algae ingest the aforementioned toxins when they consume the algae and as other fish and birds consume the algae-predators, the toxins “travel up the food chain”. Exposure of aquatic wildlife to toxins produced by HABs can disrupt their reproductive and behavioral processes [9]. Aside from toxins, the physical presence of algae also proves fatal to aquatic wildlife. Algae filament due to its microscopic size and large availability, can clog the gills of fish and smaller wildlife which ultimately leads to their death [2]. Furthermore, algae presence on surface water prevents “sunlight” penetration which has a direct effect on bottom plant life [9].
HABs also have negative impacts on coastal and water-reliant industries as they close beaches, worsen catches from fisheries, and ward away potential tourists. Ingestion of toxins by aquatic wildlife along with increased pressure from “heavy fishing” has drastically impacted desired-fish population. This alongside government bans on consumption of certain fish caught from HAB infested waters has put immense strains on the fishing industry. Due to the foul odors and murky waters near HABs, fewer tourists are visiting lakes and other water bodies. Potential threat to human health from HAB toxins has rendered numerous water bodies unsuitable for recreational use. From the years 1987 to 2000, it is estimated that HABs cost 82 million dollars in losses annually to US fishing and tourism industry [10]. This figure has not taken into account depreciation of property. A more recent study found that just in Ohio, HABs in lakes caused approximately 42 million dollars in losses between 2009 and 2010 [9]. Due to increasing frequency and severity of HABs, economic losses will continue to rise.
As algae dies and decomposes, it consumes dissolved oxygen that otherwise would have been used by aquatic wildlife. Most bodies of water can sustain this ecological process when there is a limited algae population but with excessive algae blooms, too much dissolved oxygen is consumed by the algae which results in the creation of hypoxic “dead zones”, where life cannot be sustained due to a lack of oxygen, as shown in Figure 3 [8]. Immobile aquatic wildlife such as bottom plant life and “slow moving animals” die from hypoxia, which has a ripple effect on the food web present in the body of water. Predators of algae ingest the aforementioned toxins when they consume the algae and as other fish and birds consume the algae-predators, the toxins “travel up the food chain”. Exposure of aquatic wildlife to toxins produced by HABs can disrupt their reproductive and behavioral processes [9]. Aside from toxins, the physical presence of algae also proves fatal to aquatic wildlife. Algae filament due to its microscopic size and large availability, can clog the gills of fish and smaller wildlife which ultimately leads to their death [2]. Furthermore, algae presence on surface water prevents “sunlight” penetration which has a direct effect on bottom plant life [9].
HABs also have negative impacts on coastal and water-reliant industries as they close beaches, worsen catches from fisheries, and ward away potential tourists. Ingestion of toxins by aquatic wildlife along with increased pressure from “heavy fishing” has drastically impacted desired-fish population. This alongside government bans on consumption of certain fish caught from HAB infested waters has put immense strains on the fishing industry. Due to the foul odors and murky waters near HABs, fewer tourists are visiting lakes and other water bodies. Potential threat to human health from HAB toxins has rendered numerous water bodies unsuitable for recreational use. From the years 1987 to 2000, it is estimated that HABs cost 82 million dollars in losses annually to US fishing and tourism industry [10]. This figure has not taken into account depreciation of property. A more recent study found that just in Ohio, HABs in lakes caused approximately 42 million dollars in losses between 2009 and 2010 [9]. Due to increasing frequency and severity of HABs, economic losses will continue to rise.