Current Ecological Issues of the Great Lakes Jim Diana, Director Michigan Sea Grant College Program

The Great Lakes  20% of world’s surface freshwater  5 of 9 largest lakes in world  Historic role in transportation and settlement  Large human population depending on the region  Multiple uses throughout history  20% of world’s surface freshwater  5 of 9 largest lakes in world  Historic role in transportation and settlement  Large human population depending on the region  Multiple uses throughout history

Take Home Message  Humans have had a love – hate relationship with the Great Lakes  The lakes have served for economic, societal, and ecological value since humans first set foot in this region  The lakes have suffered massive damage due to human misuse, both intentional and unintentional  The lakes have also rebounded dramatically due to human intervention and luck  Challenges remain for the future

Early History  An important resource for aboriginal communities – food, water, and transportation

Early History  An important transportation route for development and discovery of middle America

Early European History  An important industrial resource for timber, waste disposal, shipping, and food

An Important Point  By the early 1800s, the lakes were already dramatically altered (the Cholera epidemic) YearDeathsRate Per 100, , , , ,4242,

Clearing Wetlands

WetlandForestWet Prairie Clearing Wetlands

Ship Canals

Dams NowThen Map courtesy of Troy Zorn, Michigan Dept. of Natural Resources

Logging Very common in 1900s Easy to catch Degraded habitat from logging Extinct in Michigan by 1930.

Fishing Lake Sturgeon

Commercial Fishing

High valueLow value Commercial Fishing

Pollution  Cholera epidemic of Chicago, 1854  Sawdust, tannery effluent by 1900  Eutrophication from sewage discharge in the early 1900s  PCB and DDT contamination from manufacture by 1960  Serious water contamination from industry, sawdust to petroleum products and animal wastes  Airborne contaminants and contaminated sediments  Cholera epidemic of Chicago, 1854  Sawdust, tannery effluent by 1900  Eutrophication from sewage discharge in the early 1900s  PCB and DDT contamination from manufacture by 1960  Serious water contamination from industry, sawdust to petroleum products and animal wastes  Airborne contaminants and contaminated sediments

Time Magazine (1965) – “Lake Erie is dead” Pollution

The Common Carp  Deliberate introductions  Carp, Pacific salmon  Deliberate introductions  Carp, Pacific salmon Invasions

 Unintentional introductions  Pink salmon, smelt  Unintentional introductions  Pink salmon, smelt

 Immigration through ship canals  Sea lamprey  Immigration through ship canals  Sea lamprey Invasions

 Immigration through ship canals  Alewife  Immigration through ship canals  Alewife

 Ballast water  Zebra mussel  Ballast water  Zebra mussel Invasions

 Ballast water  Quagga mussel, water flea, goby  Ballast water  Quagga mussel, water flea, goby Round GobyRuffe BythotrephesQuagga Mussel Invasions

Salmon Fishing  Introduced 1969 to control alewife  Now multibillion dollar industry  Introduced 1969 to control alewife  Now multibillion dollar industry

No predators Overfishing Lamprey Massive Alewife Die-off Lake Erie is dead Cuyahoga River burns DDT Banned Lamprey Control Clean Water Act Salmon stocked DDT use banned Salmon Control Alewives Lake trout Return PCB production banned 1984 Alewives Decline drastically Sport Fishery at $1 Billion Rehabilitation

The Future? – Lake Huron  In my view, this is the current ecological change that is most important to our future  Mussel invasion and increased water clarity  Reduced plankton and changes in food web  Loss of stocked salmonids  Rebound of native species  Change in economic conditions  In my view, this is the current ecological change that is most important to our future  Mussel invasion and increased water clarity  Reduced plankton and changes in food web  Loss of stocked salmonids  Rebound of native species  Change in economic conditions

Mussels and clarity  Dreissenids consume energy and nutrients that supported fish  Round gobies have proliferated lakewide, can feed heavily on Dreissena  Dreissenids consume energy and nutrients that supported fish  Round gobies have proliferated lakewide, can feed heavily on Dreissena

Loss of Plankton

Loss of Diporeia

Change in Forage Fishes

Loss of Chinook Salmon

Rebound of Natives

 Similar trends in other native fishes Smallmouth bass Do we change from a fishery supported by stocking to a much lower production of natural fish?

Economic effects Estimated $19 million loss in 10 coastal communities

Another Problem: Asian Carp  Imported by fish farms  Escaped into the Mississippi  Now very close to Lake Michigan  DNA in water of Calumet Harbor  Imported by fish farms  Escaped into the Mississippi  Now very close to Lake Michigan  DNA in water of Calumet Harbor

Other Comparable Changes  Botulism spread through the system  Increased growth of nuisance algae and harmful algal blooms  Dead zones in deep water of Lake Erie  Botulism spread through the system  Increased growth of nuisance algae and harmful algal blooms  Dead zones in deep water of Lake Erie

Summary  Dramatic deterioration and cleanup  Has required continual reaction and money input  Has resulted in significant improvement and environmental law  Needs continual intervention  Dramatic deterioration and cleanup  Has required continual reaction and money input  Has resulted in significant improvement and environmental law  Needs continual intervention

Contacts & Questions Jim Diana: Phone: (734) Web: