Lake Michigan’s Changing Nearshore: Understanding Type E Avian Botulism Outbreaks at Sleeping Bear Dunes National Lakeshore

Emily Tyner1,2, Brenda Moraska Lafrancois1, Harvey Bootsma2, Chris Otto2

1. UWM-School of Freshwater Sciences

2. National Park Service-Sleeping Bear Dunes National Lakeshore

Photos: A.Van Zoeren

GLRI Project #91Predict and prevent avian botulism outbreaks

• Beach monitoring for avian mortality

• Investigate toxin pathways

• Confirm links between botulism outbreaks and environmental conditions

• Targeted benthic habitat mapping

Beach Monitoring3 study sites monitored every 7-10 days , June-November

Door County

NWHC & Wisconsin DNR (2010), AMBLE Volunteers (2011)

Eastern Upper Peninsula

Common Coast biologist

w/ support from Seney NWR

Sleeping Bear Dunes NL

Volunteers & park staffPhoto credit: Sharon Cobb

Jenny Chipault, USGS-NWHC (2012)

Bird Mortality Monitoring

SedimentSediment

Potential Pathways

D. Blehert, USGS (2008)

Clostridium cells and spores (<1 µm size)

Where are some likely micro-habitats for C. botulinum?

At the base of mussel aggregates where pseudofecesand organic substrates collect

Under mats of sloughed Cladophora

Cladophora with marl deposits

At the base of mussel/Cladophoraaggregates

Sediments below any of these materials

Sheridan Haack, USGS Michigan Water Science Center, 2012

1. Water temperature + hydrodynamics

Botulism outbreaks and environmental conditions

2. Mussel, round goby, invertebrate counts

3. Transport of Cladophora, sediment, invertebrates

4. Dissolved oxygen conditions

4. Dissolved oxygen conditions

Benthic Habitat Mapping

• Highlights depositional areas

– Cladophora Graveyard

– Sleeping Bear Point

• Anoxic Cladophora mats documented in these areas

Sleeping Bear Point, 65 ft, Oct 2011

Acknowledgements

UWM-Bootsma LabHarvey BootsmaBen TurschakErin WilcoxLisa DeGuire

National Park ServiceBrenda Moraska LafrancoisAlicia HighamDan RayChirs OttoSue JenningsEmily KobernikEmma KellyChris JohnsonDave Schroeder

UWM, NPS, GLSC

currents

bathymetry

growing conditions

Cladophora sloughs and

settles

Sediment,C. botulinum,invertebrates

Cladophora decays

Sediment,C. botulinum,invertebrates

currents,disturbance (D.O.)

temp

Sediment,C. botulinum,invertebrates

Nearshoreand/or offshore

food webstoxin

intoxicated invertebrates,

particles

Re-suspensionDeposition DepositionDecay

Birds

Fish

toxin

toxin

storms, seiche, upwelling, turnover

Cladophoragrows

Growth

seasonal migration; feeding habits

BODM Distribution of anoxic areas

BGM

Air temperature Wind Sloughed Cladophora C. botulinum distribution

distribution

TPM

Water temperature Current Cladophora settling Toxin distribution

(velocity, direction)

CGM CDM

Nutrients Cladophora sloughing Carcass distribution

(P, N, O2)

Light Hydrodynamic model Cladophora growth

Bathymetry Cladophora maps

(Depth, lake level)

???

Loons

Dreissenid nutrient inputs

Fish

Pathogens

Lisa Fogarty and Riley

Cladophora senesces

Cladophora Biomass Peaks

epiphytes ↑invertebrates↑

Dreissena (now)

Point Sources (historically)

toxin

high temps competition

DOM ↑Temps Hi

Prod:Resp ↓DO ↓

epiphytesinvertebrates

mussels

Birds

storms, currents

epiphyteburden

Cladophora sloughs & drifts

epiphytesinvertebrates

mussels

toxin

Cladophora re-growth

storms,seiche

Cladophora deposits

[ON SHORE]

epiphytesinvertebrates

mussels

toxin

Cladophora deposits [IN LAKE]

epiphytesinvertebrates

mussels

toxin

lowlake levels

light

substrate nutrients

temp

invasions

migration

feeding habits

Burial,unburial

Burial,unburial

Fish

animated version

Jul-DecJun-Jul

(Oct)Jul-Dec

Jun(Sep-Oct)NPS