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Algal Blooms. The Effects on Fish. Team 8 : Olivia Bruce , Emily Clifford, Yanting Huang, Aaron Vincent, Shakil Kanji , Jeanne Ho. Table of Contents. Algae Algal blooms Harmful Algae Blooms (HABs) Conditions for blooms How gills work Model Effects on fish Model - PowerPoint PPT Presentation


Algal Blooms

Algal BloomsThe Effects on FishTeam 8: Olivia Bruce , Emily Clifford, Yanting Huang, Aaron Vincent, Shakil Kanji , Jeanne HoTable of ContentsAlgaeAlgal bloomsHarmful Algae Blooms (HABs)Conditions for bloomsHow gills workModelEffects on fishModelEffects on humans and surrounding environmentToxinsCanadian ExamplesInternational ExamplesRelated IssuesSolutionsInteresting FactsMoral and Ethical ImplicationsResourcesReflectionAlgaeFresh-water algae (phytoplankton):vary in shape and colorare found in a large range of habitats, such as ponds, lakes, reservoirs, and streams. are a natural and essential part of the ecosystem . are the base of the aquatic food chain.The following algae are examples of algae that can cause harmful algal blooms:Cyanobacteria (blue-green algae)Pfiesteria piscicida living in estuariesHarmful marine algae occurring in oceans like Karenia brevis

ALGAL BLOOMSUnder certain conditions, several species of true algae and cyanobacteria (blue-green algae) are capable of causing:excessive accumulations of foams and scumdiscoloration of the waterAlgal "bloom" : When the algae population in a lake or a river increase explosively. Lakes, ponds, and slow-moving rivers are most susceptible to blooms. In oceans, occurs most frequently in the Pacific Northwest

ALGAL BLOOMS CONTINUEDUsually float on the surface and can be many inches thick, and mostly occur near the shoreline.Blooms can look like foam, scum, or mats on the surface of water bodies.Can be blue, bright green, brown, or redMay look like floating paintSome blooms do not affect appearanceBlooms can be suspended at various depths in the waterDepends on factors such as light, phosphorus and nitrogenHarmful Algae Blooms (HABs)All algae blooms are not harmfulResearchers agree that between 30% to 50% of algae blooms are harmlessNon-toxic algae blooms could occur, and these are harmlessHarmful Algae Blooms (HABs) are those that negatively impact fish and other organisms producing:Toxic effects in humans and other organismsPhysical problems in fish and shellfishOdours and discolouration of water and fish habitatsTheir occurrence are completely natural in some cases, as a result of the movement of certain ocean currents.In other cases, they appear to be linked to increased nutrient supply from human activities

Conditions for BloomsHigh nutrient levelsEspecially an excess of phosphates and nitratesMay be the result of pollutionWaste breaks down, releasing nutrients into waterCreates an excess of nutrients normally found in that ecosystemFertilizer runoff, septic tank overflows, etc.High air and water temperaturesBetter for growthBlooms more common in more places due to general temperature increase in global waters (Global Warming)Most often occur in late summer to early fall

8How Gills WorkWater comes in through the mouth, and goes through the gillsconstant streamGill rakers filter the waterOxygen is absorbed through the thin membranes of the gill fillaments into the blood

How Gills work - VideoPublic - Windows Live

Watch video AG 1Make bigger12Effects on FishExamples of fish that have been known to carry toxins: blackfin snapper, hogfish, barracuda, king mackeral etc.Depletes oxygen from the waterSuffocates fishReleases toxins when algae diesMay be lethalIf not, may present neurological symptoms, or will present in higher trophic levelsCauses salt regulation to break downAlgae accumulates in gillsIrritates gillsMucus formsThis, in turn, may affect consumers of these fish, resulting in bioaccumulation of toxinsMucus forms on gillsMechanical damage, such as disruption in epithelial gill tissues in fish, resulting in asphyxiation

Effects on Fish - VideoPublic - Windows Live

Watch video AG 2Make bigger15EFFECTS ON HUMANS AND SURRONDING ENVIRONMENTFish kills = loss of food/moneyNot aesthetically appealing Effect on property sales/development in surrounding regionsEffect tourism ratesEffect on water supplyCannot be used for drinking, or swimmingGives water a bad odourWhen algae decomposes, it needs oxygenReduces oxygen supply for the fish in the lakeWater becomes poisonous and toxicHarmful to surrounding environment (i.e. wildlife and fish)Recreational use of lake (no swimming, boating etc)Seafood becomes toxic and can harm humans if they ingest a toxic fish

Economic fisheries in south east asia16EFFECTS ON HUMANS CONTINUEDSwimming in affected areas could cause eye and skin irritation and burning as well as other hay fever-like allergic reactions.Winds could blow toxic gases released by some species of algae onshore, negatively effecting people.The toxic aerosol gas released by the species Karenia brevis could cause respiratory irritation, such as coughing, sneezing and tearing.Swallowing contaminated water could also lead to:Liver toxicity (i.e. increased serum levels of liver enzymes)Kidney toxicityNeurotoxicityIngesting water contaminated with toxins produced by algae blooms could produce the following reactions:Headaches and Abdominal PainNausea, Fever and VomitingDiarrhoea

EFFECTS ON HUMANS CONTINUEDToxic Effects resulting from contaminated shellfish/fish/water:Amnesic Shellfish Poisoning (ASP)Toxins like domoic acid produced by algae of genus Pseudo-nitzschiaCan be treated and curedObtained mainly from molluscan shellfish but can be derived from certain fish species and sea birdsclams, oysters, anchovies, etc.Result in gastrointestinal and neurological disorders, may result in death (severe cases)Paralytic Shellfish Poisoning (PSP)Caused by toxins produced by algae of Genus Alexandirium No known cure, fatalObtained from bivalved/non-bivalved shellfishlobster, oysters, etc.Results in neurological disorders and symptomsParalysis in respiratory organs may lead to deathEFFECTS ON HUMANS CONTINUEDCiguatera Fish Poisoning (CFP)Results in neurological, gastrointestinal and cardiovascular symptomsCan be treated, no known cureObtained from mainly tropical reef fishmackerel, parrot fish, tang etc.Diarrhetic shellfish poisoning (DSP)Obtained from types of shellfish and fishRazorfish, scallops, etc.Can be treated and curedResults in gastrointestinal symptomsNeurotoxic Shellfish Poisoning (NSP)Caused by a species of algae called Karenia brevisCan be treated and curedCommon gastrointestinal, neurological and asthma-like respiratory disturbance symptomsObtained from shellfish, fish, and small sea mammalsscallops, sea turtles, sea birds, etc.

ToxinsThe following neurotoxins affect the nervous system in humans.Anatoxin-aAnatoxin-a(s)SaxitoxinNeosaxitoxinThe following hepatotoxins affect the liver in humans.MicrocystinsNodularinsCylindrospermopsinThe following tumour promoters are chemicals that can increase tumour growth in humans.MicrocystinsLipopolysaccharides are chemicals that can affect the gastrointestinal system.

Examples of Toxins and their Chemical Structures

22CANADIAN EXAMPLESALBERTADue to increased summer temperatures, green-blue algal blooms development in Alberta lakesCaution notices released throughout the summer by Alberta Health Services

Pigeon Lake 2009

Lac La Nonne 2009Eastern Canada ASP/DSP/PSP Toxin Locations (1997)

INTERNATIONAL EXAMPLESEFFECTS ON OTHER MARINE ANIMALS:california case study(june 2008)Investigation of algal toxin effects on fetal brain development of sea lions was conducted by John Ramsdell of NOAA's Centre for Environmental Health and Biomolecular Research in Charleston, SC, along with Tanja Zabka, a veterinary pathologist at the Marine Mammal Centre Exposure to increased levels of domoic acid (natural chemical released by toxic algal blooms) result in behavioural abnormalities in California Sea LionsIncrease of epileptic seizures Newly found chronic disease27Related IssueFish Kill: The Neuse River 2009Massive fish kill in the Neuse River, North Carolina during August-October 2009Millions of fish killedApproximately 90%+ were MenhadenOther species include flounder, shrimp, blue crab

FISH KILL: THE NEUSE RIVER 2009 CONTINUEDFactors contributing to massive kill:Increase in precipitationRun-off flowed into the river carrying sewage, fertilizer, waste from petsIncrease in algal bloom activity Increased temperature during the summerCalm weather conditions reduced salt and fresh water mixingCreates layers in the water Difficult for oxygen to passDense populations of Menhaden Gather during late summer before heading to the seaRelated IssueAlgal Blooms in Lake VictoriaSummer 2009, Lake Victoria of Ggaba, UgandaDepletion of tilapia fish due to algal bloomsIncrease of pollution, precipitation and frequent warm weather contribute to algal bloom growth

ALGAL BLOOMS IN LAKE VICTORIA CONTEffects of Algal Blooms:Local fishermen/residentsReduced amount of fish to consume and/or sellWater no longer of household useReduced income for fishermenLess money for educational fees necessary needsAlgal blooms themselves may be harmful and contain toxinsReduced amount of tourism due to unappealing terrainEconomic income of area is reduced: no tourism results in less profits for local businessesWater rationing in the Kampala regionAlgal blooms clogged water treatment plantsUnbalanced natural ecosystemReduced amount of fish and other surrounding speciesNatural filters such as swamps are overwhelmed

ALGAL BLOOMS IN LAKE VICTORIA CONTFactors contributing to algal bloom growth:Increase in precipitation this seasonFrequent warm weatherOver fertilization due to run-off water:Unregulated dumpingIndustrial waste create high levels of ammonia which suffocate fishLack of treatment and cleaning of industrial effluents (treated sewage discharged into the lake)Urban farming by local farmersChemicals carried to the lake by rainfall streamsLocal use of charcoalContributes high levels of carbon to the lake

ALGAL BLOOMS IN LAKE VICTORIA CONTINUEDSolutions:Fish breeding sites added to the lake to