American Eel
Anguilla
rostrata
Copyright, Garold
Sneegas
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American Eels are long,
narrow, snake-like fish.
They can grow to almost five feet long.
The color of these eels
depends on their age and habitat.
Older eels are usually dark brown or greenish, with
yellowish-white bellies. Their color can change from light
to dark within a few hours. This helps them blend in with
their surroundings.
The scales of these fish
are embedded in the skin, which is covered with a thick
mucus coating. American Eels have large heads.
American Eels are unique
because they are one of the few fish that are catadromous.
This means they spend most of their lives in fresh water,
but return to the sea to breed.
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Copyright, Doug
Stamm/ProPhoto
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Copyright, Garold
Sneegas
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The American Eel's life
cycle starts as an egg in the Sargasso Sea near the Bahamas.
Tiny larvae, called "glass eels," hatch and drift in ocean
currents. Glass eels are very thin, like ribbons, and they
are transparent. It takes almost a year before these tiny
eel larvae reach the coast of the United States. Many glass
eels are eaten by predators
before they ever reach fresh water.
When glass eels reach the
coast, they metamorphosize
(change) into a new body shape. These rounder, darker eels
are now called "elvers."
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Elvers are about 3 inches
long when they enter fresh water in the spring. Most elvers
swim upstream into rivers
and smaller streams.
Some stay in bays and mouths of rivers where the water is
brackish (part salt/part fresh).
Elvers continue to grow
as they swim upstream. It will be at least three years
before they mature into adulthood and are ready to return to
the sea to mate. Many eels live up to 20 years in fresh
water before they return. American Eels always go back to
the Sargasso Sea to mate.
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Northeast Eel and Elver
Company
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Copyright, Andrew Fahlund
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Copyright, Garold
Sneegas
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As American Eels move
upstream, they often have to navigate around obstacles. Eels
can climb over rocks, dams, and even waterfalls.
They have the ability to
absorb oxygen throught their skins to breathe. This allows
them to survive out of water for several hours. If an eel is
found doing this, it is most often on a damp, rainy
night.
Eels can also travel by
underground waterways. This explains how eels are found in
ponds
that don't have a stream leading to it.
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American Eels are mostly
nocturnal.
They lay buried in mud or gravel during the day. They also
hide under logs or boulders, below undercut banks, or in
dense vegetation
(water plants). Eels prefer quiet, slow-moving water with
muddy bottoms.
American Eels are not
picky eaters. Foods include: small fish, shrimps, crayfish,
aquatic
insect larve, snails, mussels, aquatic worms, and
amphibians
(frogs, toads, salamanders). Eels will also eat animals that
fall into the water, such as terrestrial
insects and earthworms. They are carrion-eaters as well,
meaning they eat dead animal matter.
Predators
of eels include larger fish, gulls, and eagles.
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Copyright, Garold
Sneegas
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American Eels can live a long
time. One specimen, captured as an elver, lived in an aquarium for 85
years.
Relationships in
Nature:
Relationship to
Humans:
American Eels are eaten by many
people, especially in Europe and Asia. Because of this, elvers are
captured and exported to other countries. Recently, scientists are
becoming concerned that "over-fishing" of eels may be impacting them
in a negative way. American Eels are helpful because they control
insect and fish populations. They also eat dead animal matter and
other stinky things that other animals won't eat. This helps
waterways stay clean and healthy. American Eels are basically
harmless, but large ones will bite if handled.
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SCIENTIFIC
CLASSIFICATION
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KINGDOM
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Animal
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PHYLUM
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Chordate
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CLASS
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Bony
Fish
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ORDER
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Anguilliformes
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FAMILY
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Anguilidae
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GENUS
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Anguilla
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SPECIES
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Anguilla
rostrata
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