Three Major HAB species in Lake Erie

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1 Harmful Algal Blooms in Lake Erie Thomas B. Bridgeman U. Toledo Tl Lake Lk Erie Ei Center

2 Three Major HAB species in Lake Erie Microcystis aeruginosa Cladophora spp. Lyngbya y wollei / Plectonema wollei

3 Major groups in Lake Erie Bacillariophyta (Diatoms) Chlorophyta (Green) [Cladophora] Cyanobacteria (Blue-green) [Microcystis, Lyngbya]

4 Blue-green Algae in Lake Erie Anabaena Aphanizomenon Microcystis

5 Microcystis bloom August 2003 Toledo Water Intake

6 Why should we care? Microcystis may produce a toxin (Microcystin) If ingested, toxin damages the liver Brazil 1988, 1996: 88 deaths when reservoir developed Microcystis bloom, 55 dialysis patients poisoned (1996) many animal poisonings Skin contact t may cause allergic rash

7 Economic Costs City of Toledo spends an extra $10,000 per day to treat drinking water during Microcystis blooms. Recreational fishing and boating affected. Rotten smell, fouled beaches may cause visitors to go elsewhere for recreation.

8 Research Goals Monitor and quantify annual Microcystis blooms Examine environmental influences that may explain variation in Microcystis blooms between years.

9 Monitor and quantify annual Microcystis blooms Quantify Microcystis in archived plankton tows from 2002-present (~400 samples)

10 To otal M icrocy ystis vo olume Micro cystis (ml m yr ) (ml / m 2 )

11 Maumee River summer discharge Mean M aumee Rive er Discharg ge (ft 3 s -1 ) June July August (m 3 x 10 5 )

12 Microcystis Blooms vs Summer River Discharge (ml / m 2 ) -1 stis (ml m -2 yr ) Microcys volume ocystis tal Micro Tot r 2 = Jun. 1 - Aug. 15 Total discharge (m 3 x 10 9 )

13 Microcystis Blooms vs Winter-Spring River Discharge r 2 = tis (ml m -2 yr -1 ) Microcyst Jan. 1 - April 30 Total discharge (m 3 x 10 9 )

14 (S.J. Ross) Cladophora Grows best in Clear water Rocky substrate Non-toxic A bathtub ring species Mainly a problem in eastern Lake Erie (E. Young) (Wisconsin DNR)

15 Lyngbya y Wollei Nuisance blooms most often reported in northern Florida and Georgia springs beginning in the 1970s, coinciding with increasing agriculture and nutrient enrichment of groundwater Mats are benthic for most of year but become buoyant due to trapped oxygen bubbles. Strains of Lyngbya wollei in southeast US are known to produce potent neurotoxins Toxin production has not been found in Lake Erie Lyngbya A. Pinowska Tough polysaccharide sheath allows filaments to persist year-round, requires Calcium

16 September-October Benthic mats become buoyant and float to surface (Maumee Bay State Park) T. Fisher

17 September 2006 In protected area in front of the U. Toledo Lake Erie Center, approximately 200 tonnes (wet weight) of Lyngbya covered a 100m stretch of shoreline.

18 Floating Lyngbya mats 5 miles offshore

19 Lyngbya Lyngbya survey, summer 2008 (Yellow = shoreline, blue = lake bottom)

20 Lyngbya Lyngbya beds at MBSP

21 Why Lyngbya y rather than Cladophora? Lyngbya does not have a means of attaching to hard substrate (unlike Cladophora), but can adhere to softer substrates such as sand and crushed zebra mussel shells Lyngbya grows well under low light conditions (unlike Cladophora) Cladophora Lyngbya Long filaments X X Benthic X X Light preference Bottom type High Rocky, ZM Low Sandy, ZM frag