The Zebra Mussel Dreissena polymorpha © Keith Klestinski 2003

What is the BIG Problem? Spread and Impact Lessons Learned in the Great Lakes Region Kansas Department of Wildlife and Parks

PROGRESSION OF THE ZEBRA MUSSEL (Dreissena polymorpha) DISTRIBUTION IN NORTH AMERICA 1988-2002 Source: U.S. Fish and Wildlife Service

Zebra Mussel Family Tree Classification Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Veneroida Family: Dreissenidae Genus: Dreissena Species: polymorpha

byssal threads used for attaching to a substrate Zebra Mussel Anatomy byssal threads used for attaching to a substrate

The Siphons The large opening of each mussel is the incurrent siphon, the smaller opening is the excurrent siphon.

Life Cycle of Zebra Mussels

Zebra Mussel Metamorphosis Free Floating Larval State

IMPACTS Zebra Mussels can have great impacts on our economy, and lakes & oceans' ecosystem. Most significantly, the mussels are extremely efficient filter-feeders, consuming large portions of the microscopic plants and animals which form the base of the food chain. Over time, this feeding behavior can affect a lake's entire ecological balance, causing significant shifts in native species populations. In addition, one of negative effects are caused by their rapid reproduction. Zebra Mussels have clogged up water and drain pipes at municipal water supplies and at industries. They are expected to cost the US $5 billion in control efforts and reparation. Zebra Mussels have displaced native freshwater mussels of the area, and drastically altered the food web. With no native predator, the zebra mussel population continues to grow and no immediate end is foreseen.  (modified from  http://massbay.mit.edu/exoticspecies/invaders/factsheet.html). 

Industrial Costs

Let’s Relate What We Have Learned about Zebra Mussels to the Characteristics of Living Things Reproduction Heritability of Traits Growth and Development Homeostasis (steady state) Organization

The Zebra Mussel’s Disturbing Food Web Zebra mussels primarily eat photosynthetic algae. All the foods they eat are rich in calcium. Because there is no shortage of algae, zebra mussels can't be hurt by starvation. Zebra mussels use calcium for many things, including repairing a damaged shell. Zebra mussels, unfortunately, do not have many predators here because they do not naturally exist in the North American environment. However, there are many things that eat the zebra mussel such as sturgeon, carp, some diving ducks, the round goby, birds, some crayfish, and other creatures. All of these predators are still not enough to make a dent in the zebra mussel population.