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What You Should Know About Cyanobacteria:. Ecology and Management for Public Beaches. Webster Lake, Franklin, NH. Cyanobacteria Overview. What are cyanobacteria? Previously referred to as blue-green algae Single-Celled organisms lacking a nuclear membrane Contain photosynthetic pigments
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What You Should Know About Cyanobacteria: Ecology and Management for Public Beaches Webster Lake, Franklin, NH
Cyanobacteria Overview • What are cyanobacteria? • Previously referred to as blue-green algae • Single-Celled organisms lacking a nuclear membrane • Contain photosynthetic pigments • Chlorophyll-a and Phycobilins (produce the characteristic blue-green color) • Many different forms: filaments, colonies
Common Cyanobacteria in NH Lakes Aphanizomenom Merismopedia Microcystis Gleotrichia Oscillatoria Anabaena
Adaptations and Advantages • Nitrogen Fixation • Heterocysts: specialized cells containing nitrogenase enzyme able to convert gaseous nitrogen (N2) to ammonium (NH4+) • Advantage-cyanobacteria are able to use a nutrient not readily available to other algal genera Heterocyst
Adaptations and Advantages • Gas Vesicles • Some genera have gas vesicles to control buoyancy • Advantage-allows cyanobacteria to optimize growth based on sunlight and nutrients N N N P N N P N N P P P P P N P P N P P N
Adaptations and Advantages • Akinetes: • Resting cells. The cells function as an asexual resting state capable of resisting harsh environments (winter) and can germinate to form new cells when conditions improve • Advantage-cyanobacteria can adapt to any situation and grow only when conditions are optimal Germinating Akinetes
Growth Requirements • Sunlight • Warm water (hot summer days) • Calm, stagnant conditions • Phosphorus
Potentially Harmful Algal Blooms • When conditions are right, algae may form blooms, scums, or masses
Problems with Blooms • Unsightly • Taste Problems: algae can lead to bad tastes in the water including bitter, fishy, and sweet. • Odor Problems: algae can cause water to smell fishy, grassy, like geraniums, or musty. • Fish Kills • Toxins
Toxins • Cyanobacteria produce biotoxins • Biotoxins are any toxins produced by a living organism (plant, fungi, animal, bacterium) • The toxins produced by cyanobacteria are collectively referred to as cyanotoxins • Toxins are stored in cells and released upon cell lysis or death t t t t t t t t t t t t t t t t t t t t
Toxins • Common toxin producers in New Hampshire • Annie, Phannie, Mike and Ozzy – the fearsome foursome Mike Ozzy Annie Phannie
Toxins Common Cyanotoxins in New Hampshire
Toxins • Focus on microcystins in drinking and recreational waters • Many different forms of microcystins • Most frequent and most toxic form is microcystin-LR
Toxins • Lethal dose (LD-50) of microcystin = 25 - 150 µg/kg of body weight (0.025 - 0.150 mg/kg) • Compared with some of the most venomous snakes in the world Note: this comparison based on route of exposure (intraperitoneal). LD-50 can differ among different exposure routes
Toxins Animal Health Effects Species Killed Country • Argentina • Australia • Canada • England • USA • cattle • cattle, sheep • cattle, waterfowl • dogs, fish • dogs, cattle, human? In July 2002, a Wisconsin teenager died two days after swimming in a golf-course pond that had a bloom of Anabaena flos-aquae. A year later, an autopsy reported the death was due to cyanotoxins in the pond water (Anatoxin-a).
Toxins Human Effects ACUTE CHRONIC • Gastrointestinal effects • Nausea, vomiting, diarrhea • Hepatic illness (liver) • Dermatitis • Ear and mouth irritation • Liver damage • Tumor growth
Beach Management • World Health Organization (WHO) standard for microcystin-LR drinking water = 1.0 µg/L • Currently there are no recommended standards for recreational waters
Beach Management Protection Against Recreational Exposure to Cyanobacteria Problem: Long process – need quick response
Beach Management NHDES’ Quick Response Approach
Beach Management NH's Beach Advisory
Beach Management NHDES Microcystin Studies • Algal scum samples collected • Species identified • Freeze/thaw process • Microcystin Tube Kit analysis • Enzyme-Linked ImmunoSorbent Assay (ELISA) • 2 standards • Add reagents to all samples and standards • Several steps • Spectrophotometric Measurement and Analysis
Beach Management • 2005 Microcystin Results
Beach Management • Long-term management options • Reduce nutrient loading! • Watershed studies: identify and remediate point and non-point sources of pollution • Education and outreach initiatives: provide educational materials to homeowners within the watershed
Beach Management • Long-term management options • Utilize best management practices (BMPs) • Promote low impact development (LID) • Establish watershed ordinances
Thank You Jody Connor Limnology Center Director NH Department of Environmental Services 603-271-3414 jconnor@des.state.nh.us