(DRAFT) - Taxonomy
Species eel, American
Species Id M010131
Date 27 AUG 96
TAXONOMY
NAME - eel, American
OTHER COMMON NAMES - American eel
ELEMENT CODE - 05/30/84
AOU CODE - 03/29/85
09/10/87
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Chordata,
CLASS AND SUBCLASS - Osteichthyes,
ORDER AND SUBORDER - Anguilliformes,
FAMILY AND SUBFAMILY - Anguillidae,
GENUS AND SUBGENUS - Anguilla,
SPECIES AND SSP - rostrata,
SCIENTIFIC NAME - Anguilla rostrata
AUTHORITY - Lesueur 1817
TAXONOMY REFERENCES - 3107 and 816
COMMENTS ON TAXONOMY -
The specific distinctness of American eel and European eel
is still being questioned *3104*
Taxonomy - 1 (DRAFT) - Status
Species eel, American
Species Id M010131
Date 27 AUG 96
STATUS
Coded Status
Migrant
Commercial/consumption
Commercial/bait
REFERENCES FOR STATUS - 58
COMMENTS ON STATUS -
The American eel supports valuable commercial and limited recreational
fisheries throughout its range. Harvested adults often are shipped alive or
frozen to Europe where they are frequently smoked before marketing and a
fishery for elvers (immature eels typically less than 60 mm long) has
recently begun in the South Atlantic Bight. The American eel is an
important prey species of larger marine and freshwater fishes and is a
predator on a variety of other animals including commercially important
crabs and clams. Eels contribute to the loss of nutrients from freshwater
rivers and lakes due to their great organic intake, large numbers, lengthy
stay in freshwater, and subsequent migration to sea.*58*
Status - 1 (DRAFT) - Distribution
Species eel, American
Species Id M010131
Date 27 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
HABITAT - Aquatic
REFERENCES FOR HABITAT - 842 and 3110
LAND USE -
Water
Streams and Canals
Bays and Estuaries
REFERENCES FOR LAND USE - 842 and 3110
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Marine, subtidal OW0 H 0
Estuarine, intertidal AB.
Riverine, upper perennial SB1
Estuarine AB.
Riverine, upper perennial SB.
Riverine SB.
Riverine SB1
Marine OW0
REFERENCES FOR NWI - 842 and 3110
COMMENTS ON HABITAT ASSOCIATIONS -
Most eels have a relatively small home range and rarely move more than 100
m from the point of release. It is suggested that large eels may establish
territories in lower marsh areas and thereby restrict smaller eels to
smaller high marsh creeks.*58*
POTENTIAL NATURAL VEGETATION -
101 Oak - Hickory - Pine Forest (Quercus-Carya-Pinus)
103 Southern Floodplain Forest (Quercus-Nyssa-Taxodium)
REFERENCES FOR PNV - 5473 and 5376
Habitat Associations - 1 (DRAFT) - Food Habits
Species eel, American
Species Id M010131
Date 27 AUG 96
FOOD HABITS
TROPHIC LEVEL -
Carnivore
REFERENCES FOR TROPHIC LEVEL - 3106, 842, 3110, 1359 and BKW0026
LIFESTAGE FOOD FOOD PART
General Animals Not Specified
General Annelids Not Specified
General Polychaetes Not Specified
General Oligochaetes Not Specified
General Hirudineans Not Specified
General Echinoderms Not Specified
General Molluscs Not Specified
General Bivalve Molluscs Not Specified
General Snails Not Specified
General Crustaceans Not Specified
General Malacostraca Not Specified
General Insects Larva stage
General Proturas Not Specified
General Ephemeroptera Larva stage
General Odonata Larva stage
General Plecoptra Larva stage
General Hemiptera Larva stage
General Coleoptera Larva stage
General Trichoptera Larva stage
General Diptera Larva stage
General Osteichthyes Not Specified
General Salmoniformes Not Specified
General Cypriniformes Not Specified
General Siluriformes Not Specified
General Perciformes Not Specified
General See Comments; Food See Comments
Important Animals Not Specified
Important Molluscs Not Specified
Important Bivalve Molluscs Not Specified
Important Crustaceans Not Specified
Important See Comments; Food See Comments
Juvenile See Comments; Food See Comments
Adult Annelids Not Specified
Adult Polychaetes Not Specified
Adult Oligochaetes Not Specified
Adult Hirudineans Not Specified
Adult Echinoderms Not Specified
Adult Molluscs Not Specified
Adult Bivalve Molluscs Not Specified
Adult Snails Not Specified
Adult Crustaceans Not Specified
Adult Malacostraca Not Specified
Adult Insects Larva stage
Adult Proturas Not Specified
Adult Ephemeroptera Larva stage
Food Habits - 1 (DRAFT) - Food Habits
Species eel, American
Species Id M010131
Date 27 AUG 96
LIFESTAGE FOOD FOOD PART
Adult Odonata Larva stage
Adult Plecoptra Larva stage
Adult Hemiptera Larva stage
Adult Coleoptera Larva stage
Adult Trichoptera Larva stage
Adult Diptera Larva stage
Adult Osteichthyes Not Specified
Adult Salmoniformes Not Specified
Adult Cypriniformes Not Specified
Adult Siluriformes Not Specified
Adult Perciformes Not Specified
Adult See Comments; Food See Comments
REFERENCES FOR GENERAL FOOD - 816 and 788
REFERENCES FOR IMPORTANT FOOD - 816
REFERENCES FOR ADULT FOOD - 816 and 788
REFERENCES FOR JUVENILE FOOD - 842 and 1359
COMMENTS ON FOOD -
9999S=diet 90% larval aquatic insects *816*
The diet is diverse and generally includes nearly all types of aquatic fauna
that occupy the same habitats. Eels swallow some types of prey whole, but
they also can tear pieces away from from larger deard fish, crabs, or other
items. Eels in freshwater feed on insects, worms, crayfish and other
crustaceans, frogs, and fish whereas elvers in saltwater are
planktivorous.*58*
COMMENTS ON ADULT FOOD -
9999S=eats almost any animal matter, living or dead
*1359,3106,842,3110* Also eat Megaloptera *6206*
COMMENTS ON JUVENILE FOOD -
9999S=a voracious feeder on almost all animal matter, living
or dead *1359,842*
COMMENTS ON LARVAE FOOD -
Elvers in saltwater are planktivorous. Elvers collected from the Cooper
River, South Carolina, consumed aquatic insects (mainly chironomid larvae
and adults), cladocerans, amphipods, and fish parts.*58*
Food Habits - 2 (DRAFT) - Environment Associations
Species eel, American
Species Id M010131
Date 27 AUG 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Water Temperature: Between 21-27 degrees C
G Water Temperature: Between 15-21 degrees C
G Water Temperature: Below 15 degrees C
G Water Temperature: Specified in Comments
G Dissolved Oxygen: Specified in Comments
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 58
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
The eel's broad geographic range and diverse habitats suggest flexible
temperature requirements. The preferred temperature for eels is 16.7
degrees C. Feeding ceases at temperatures below 14 degrees C. Dissolved
oxygen requirements have not been throughly documented, but eels generally
will select water with high oxygen tension. The capacity of the adult eel
to survive in both air and water is associated with its ability to use both
brachial and cutaneous modes of respiratory gas exchange. The eel survives
better in air than in poorly oxygenated or polluted water.*58*
COMMENTS ON RESTING ADULT ENVIRONMENTAL ASSOC_ -
In MO study, 60.8% of collections were from streams of order 6 or 7 *6268* Hide
under rocks, sub. logs, or other cover during the day *1187* Final temp.
preference in MO lab study 16.7 deg. C *4921*
COMMENTS ON FEEDING ADULT ENVIRONTAL ASSOC_ -
In MO study, 60.8% of collections were from streams of order 6 or 7 *6268* Hide
under sub. logs, rocks, or other cover during the day *1187* Final temp.
preference in MO lab study 16.7 deg. C *4921*
COMMENTS ON RESTING JUVENILE ENVIRONMENTAL ASSOC_ -
In RI, elvers burrow into bottom sediment, usu. shoals or sand bars *6228*
COMMENTS ON FEEDING JUVENILE ENVIRONMENTAL ASSOC_ -
In RI, elvers burrow into bottom sediment, usu. shoals or sand bars *6228*
Environment Associations - 1 (DRAFT) - Life History
Species eel, American
Species Id M010131
Date 27 AUG 96
LIFE HISTORY
ORIGIN: native *835,1115,842*; transplanted *835,1115,842*; found in
eastern & central U.S., where its movements are not impeded by dams *1187*
BEHAVIOR: periodicity: nocturnal *1359*; catadromous, spend most of life
in fresh water or brackish water *816,788* Males remain near estuaries,
females migrate far inland. In RI, onset of daily activity and
peak activity occurred w/in the 1st 2 hrs. of darkness after sunset
*6228*; in MO, all eels found are females *1187*; in VT, females taken
were 8-23 yrs., avg 16 yrs. of age *6206*; females thought to spend
5-20 yrs. in freshwater *1187*; seward migration may begin when females are
approx. 80 cm. long *6206*; in RI, metamorphosis to sea-going from usually
occurs in Autumn *6228*; freshwater form known as yellow eels, sea-going form
known as bronze eels, due to differences in coloration *6206*. Tend to be
bottom dwellers and hide in burrows, tubes, snags, plant masses, other types of
shelter, or the substrate itself;
REPRODUCTION: adults migrate exclusively to Sargasso Sea to spawn,
from February to June, a female releasing as many as 15 to 20 million eggs,
then die. The yolk sac stage lasts a few days, and thereafter the
marine larvae are referred to as leptocephalus larvae, a stage which lasts 1
1 to 2 years, and are randomly distributed by ocean currents. The
young return to fresh or brackish water, where they ascend rivers and
live until spawning migration *1187,6202,6228,2980*; after the
leptocephalus larvae stage, they transform into transparent miniature
adults known as glass eels, when pigmentation develops they are called elvers
*6206*; juveniles spend several years in fresh or brackish water before
leaving on spawning migration *2980,1187,6206*, and are called yellow eels, a
stage which lasts several years (approximately 8 for males, 10-18 for females).
Sexual maturity occurs during the silver or bronze eel stage which lasts
about a year. At the end of this phase they migrate to sea in late summer
or fall to spawn and thereafter, presumably;
AGE & GROWTH: live to be 9 yrs.
*816,788*; in MO, most eels caught are 16-33 in. and .25-3.75 lbs., largest
was 37 in. long & 4.5 lbs *1187*; in VT, lengths ranged from 43-90cm, avg. 67cm,
and weighed 1120-1665g, avg. 638 grams *6206*;
PHYSICAL DESCRIPTION: Long and cylindrical with dorsal, anal, and caudal fins united. Brown to yellowish-brown
with paler undersides. Males seldom exceed 18 inches, while females are
reported to reach a length of 52 inches and a weight of 7 pounds or more.
SPECIES INTERACTIONS: Predators- largemouth bass (Micropterus
salmoides), striped bass (Morone saxatilis), other eels, bald eagles, other
piscivores;
REFERENCES FOR LIFE HISTORY- 835, 1115, 842, 1359, 816, 788, 1187, 6228, 6206 and 2980
Life History - 1 (DRAFT) - Management Practices
Species eel, American
Species Id M010131
Date 27 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Adverse Channelization
Adverse Creating impoundments
Adverse Construction of navigational improvements [dams, locks, etc.]
REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 835
COMMENTS ON MANAGEMENT PRACTICES -
In a SC lab study, the following chemicals commonly used in aquaculture were
found to be toxic to eels in the concentrations given: Malachite green at
.27mg/L, potassium permanganate at 3.06mg/L, formalin at 83.96mg/L, dylox at
1.31mg/L, furanace at .77mg/L, antimycin A at .09mcg/L, noxfish at 15.25mcg/L,
copper sulfate at 2.54mg/L, diquat at 39.02mg/L, salt at 17.88 G/L. *5244*
Management Practices - 1 (DRAFT) - References
Species eel, American
Species Id M010131
Date 27 AUG 96
References
*58* Van Den Avyle, M. 1984. Species Profiles: Life Histories and
Environmental Requirements of Coastal Fishes and Invertebrates
(South Atlantic) -- Amercian Eel. U.S. Fish and Wildlife Service
Biol. Rep. 82(11.24) pp 19.
788* Carlander, K.D. 1969. Handbook of freshwater fishery
biology. Life history data on freshwater fishes of the United
States and Canada, exclusive of the Perciformes. I. Iowa State
Univ. Ames.
816* Lee, D.S., Gilbert, C.R., Hocutt, C.H., McAllister, R.E.,
Stauffer, J.R., Jr. (ed.)1980. Atlas of North American
freshwater fishes. Pub. 1980-12 of N. Car. Biol. Surv, N. C.
State Mus. of Nat. Hist. Raleigh.
835* Cooper, E.L. 1983. The fishes of Pennsylvania and
northeastern United States. Penn. State Univ. Press University
Park.
842* Scott, W.B., Crossman, E.J. 1973. Freshwater fishes of
Canada. Can. Fish. Res. Board Bull. 184.
1115* Fowler, H.W. 1919. A list of the fishes of Pennsylvania.
Proc. Biol. Soc. Wash. 32:49-74.
1187* Pflieger, W.L. 1975. The fishes of Missouri. Mo. Dept.
Conserv.
1359* Bigelow, H.B., Schroeder, W.C. 1953. Fishes of the Gulf of
Maine. U.S. Fish and Wildl. Serv. Fish Bull. 53:1-577.
2980 * Cross, F.B. 1967. Handbook of fishes in Kansas. Misc.
Publ. No. 45 (ed.). Museum Natural History, Univ. Kansas
Lawrence:357.
3106* Godfrey, H. 1957. Feeding of eels in four New Brunswick
salmon streams. Fish Res. Board Can. Atlantic Prog. Rep.
67:19-22.
3107* Lesueur, C.A. 1817. A short description of five (supposed)
new species of the genus Muraena, discovered by Mr. Lesueur in
the year 1816. Acad. Nat. Sci. Philadelphia 1(1):81-83.
3110* Vladykow, V.D. 1955. Fishes of Quebec. Album 6. Eels.
Quebec Dep. Fish.
5376* Marion, W.R., Ryder, R.A. 1975. Perch-site preferences of
four diurnal raptors in northeastern Colorado. Condor
77:350-352.
5473 * Pflieger, W.L.. The stream resource of Missouri. Unpb.,
References - 1 (DRAFT) - References
Species eel, American
Species Id M010131
Date 27 AUG 96
MO Dept. of Conserv., D-J Proj. F-I-R-28, Study S-20 (ed.).
6206 * Facey, D.E. 1980. Food habits, age and growth, and sex
ratio of American eels in Lake Champlain, Vermont. UNPB., Univ.
of Vermont. (ed.):35.
6228 * Hain, J.H.W. 1975. Migratory orientation in the eel,
Anguilla rostrata. UNPB., Univ. Rhode Island (ed.):143.
References - 2