I. What is the Zebra Mussel?
a. The
Zebra mussel is a very small mussel, usually less than an inch but up to two
inches in length. They have a striped, brownish, D-shaped shell. They grow in
attached clusters and usually attach themselves to solid objects, in the same
manner as barnacles. They were native to Europe and Asia and did not appear in
the United States until the mid 1980’s.
II. How did they come the US?
a. The mussels first appeared in the Great
Lakes, where they are still rampant. They were accidentally introduced through
the dispersion of ballast water of barges from Asia and Europe. They most
likely existed in the water as larvae and matured in the American waters where
they were dumped and began to reproduce prolifically.
III. Problems Caused
a.
In order to feed, zebra mussels suck water into their bodies and filter
out microscopic particles of plants, animals, and debris. This extreme amount
of intake depletes the water of food that other marine life depend upon,
leading to the death of some species. Also, the decrease in particles in the
water increases clarity, which can hinder large fish from catching their prey
and
b. Zebra Mussels eat all algae except
blue-green algae. This results in a
harmful abundance of blue-green algae in areas that are affected.
c. Zebra Mussels attach themselves to other
objects, especially other mussels which are then smothered. They also attach
themselves to manmade structures such as motors and bulkheads, resulting in a
large amount of money being spent to clean up these structures.
Works Cited:
Invasive Species- Zebra Mussels (Dreissena polymorpha).
Retrieved March 7, 2012, from http://dnr.wi.gov/invasives/fact/zebra.htm.
Zebra Mussels: Invaders from Another Land
They came, They saw, They conquered
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