(DRAFT) - Taxonomy
Species mackerel, king
Species Id M010503
Date 27 AUG 96
TAXONOMY
NAME - mackerel, king
OTHER COMMON NAMES - kingfish, kings and serucho
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Vertebrata,
CLASS AND SUBCLASS - Osteichthyes,
ORDER AND SUBORDER - Perciformes,
FAMILY AND SUBFAMILY - Scombridae,
GENUS AND SUBGENUS - Scomberomorus,
SPECIES AND SSP - cavalla,
SCIENTIFIC NAME - Scomberomorus cavalla
AUTHORITY - Cuvier
TAXONOMY REFERENCES - 44
COMMENTS ON TAXONOMY -
Common names include king mackerel (preferred common name), kingfish, kings,
and serucho *44*.
Taxonomy - 1 (DRAFT) - Status
Species mackerel, king
Species Id M010503
Date 27 AUG 96
STATUS
Coded Status
Sport Fish
Commercial
Migrant
REFERENCES FOR STATUS - 44
COMMENTS ON STATUS -
King mackerel support commercial and sport fisheries of major importance.
In summer, large solitary king mackerel are sometimes captured off piers and
near deepwater inlets. Juvenile king mackerel sometimes mix with schools of
Spanish mackerel. The species feeds principally on estuary-dependent
species such as menhaden (Brevoortia spp.) and anchovies (Anchoa spp.).
Excessive alterations of estuaries could reduce the production of coastal
forage fish on which king mackerel feed.
Florida has historically produced about 90% of the king mackerel commercial
landings in the United States. The species is also highly regarded as a
sport fish. Sport fishermen in the south Atlantic region are estimated to
have caught 598,000 king mackerel in 1979 and 1,370,000 in 1980. In the
gulf, about 600,000 were taken in 1979 and 1 million in 1980. At times,
keen competition for this resources has led to serious user conflicts.
Major commercial catches along the Florida east coast are centered between
Cape Canaveral and Palm Beach, and on the west coast from Key West to
Naples. Although king mackerel support a year-round fishery, most are
caught in winter and early spring. The percentages of the total catch taken
from 1950 to 1974 along the east coast of Florida were 67% by trolling, 29%
by runaround gill nets, and 4% by handlines. The percentages for the west
coast were 56% for runaround gill nets, 34% for trolling, 6% for handlines,
and 4% for other methods. Purse seining has recently been permitted in
Federal waters.
Major changes in the locations and the intensity of fishing in Florida have
taken place since about 1960. The east coast center of production has
gradually shifted northward from Dade County toward Volusia County and a
spring fishery of major importance has developed off Palm Beach County near
Jupitor and Juno. As a result of higher dockside prices, fishing efforts
increased sharply: from 1969 to 1977 there was a three-fold increase in
hook-and-line vessels, 100 to 300, and gill net vessels, 12 to 33. By 1983,
the number of gill net vessels had risen to about 80, and the larger net
boat fleet had moved onto fishing grounds that had formerly been used
principally by trollers and handlers. In addition, the net fleet has
increased its efficiency through the use of spotter airplanes, monofilament
net construction, larger and deeper nets mechanically retrieved by power
rollers, and electronic equipment *44*.
Status - 1 (DRAFT) - Distribution
Species mackerel, king
Species Id M010503
Date 27 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Estuarine FL. V 1
Marine BB. V 1
Marine BB. V 1
Marine BB. V 1
REFERENCES FOR NWI - 44
COMMENTS ON HABITAT ASSOCIATIONS -
King mackerel inhabit Atlantic coastal waters. Larvae have been found off
northwest Florida and Texas between the Middle and Outer (35-183 m)
Continental Shelf. Larvae captured near Palm Beach, Florida, were closer
to shore than those captured farther north off Cape Canaveral, Florida,
Savannah, Georgia, and Cape Fear, North Carolina. North of Cape Canaveral
larvae were found near or off the shelf along the 200 m depth contour and
near the Gulf Stream. Most king mackerel larvae are collected near the
surface. King mackerel are primarily a pelagic species, but also inhabit
estuaries *44*.
Habitat Associations - 1 (DRAFT) - Food Habits
Species mackerel, king
Species Id M010503
Date 27 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
REFERENCES FOR TROPHIC LEVEL - 44
LIFESTAGE FOOD FOOD PART
Adult Osteichthyes Not Specified
Adult Clupeiformes Not Specified
Adult Percopsiformes Not Specified
Adult Invertebrate Cordates Not Specified
Adult Isoptera Not Specified
Adult Molluscs Not Specified
Adult Malacostraca Not Specified
Adult Crustaceans Not Specified
Adult Squid, Octopus Not Specified
Juvenile Osteichthyes Not Specified
Juvenile Clupeiformes Not Specified
Juvenile Squid, Octopus Not Specified
Important Osteichthyes Not Specified
Important Clupeiformes Not Specified
Important Squid, Octopus Not Specified
REFERENCES FOR GENERAL FOOD - 44
REFERENCES FOR IMPORTANT FOOD - 44
REFERENCES FOR ADULT FOOD - 44
REFERENCES FOR JUVENILE FOOD - 44
COMMENTS ON FOOD -
King mackerel juveniles and adults are primarily pelagic carnivores. They
feed mostly on schooling fish, secondarily on crustaceans, and minimally on
mollusks. The dominent prey by number (59%) were clupeids (Atlantic thread
herring) and scaled sardines, Harengula jaguana. The minor fish prey (8%)
were species of Carangidae, Lutjanidae, Pomadasyidae (Haemulidae), Sparidae,
and Triglidae. Invertebrates, particularly squid and shrimps, made up 33%
of the diet.
In south Florida, the king mackerel fed primarily on the ballyhoo,
Hemiramphus brasiliensis, followed by lutjanids (five species), clupeids,
scombrids, mugilids (two species), and serranids. The invertebrates eaten
were mostly penaeid shrimp and some squid and nematodes. In east central
Florida, clupeids (principally the Spanish sardine, Sardinella aurita) were
the dominent fish prey. Other prey were anchovies, mullet, flying fish,
drum, and jacks. Squid was the major invertebrate food; others were
nematodes, penaeid shrimp, and isopods. Most fish eaten by adult king
mackerel were about the same size: 100 to 150 mm FL *44*.
COMMENTS ON ADULT FOOD -
King mackerel juveniles and adults are primarily pelagic carnivores. They
Food Habits - 1 (DRAFT) - Food Habits
Species mackerel, king
Species Id M010503
Date 27 AUG 96
feed mostly on schooling fish, secondarily on crustaceans, and minimally on
mollusks. The dominent prey by number (59%) were clupeids (Atlantic thread
herring) and scaled sardines, Harengula jaguana. The minor fish prey (8%)
were species of Carangidae, Lutjanidae, Pomadasyidae (Haemulidae), Sparidae,
and Triglidae. Invertebrates, particularly squid and shrimps, made up 33%
of the diet.
In south Florida, the king mackerel fed primarily on the ballyhoo,
Hemiramphus brasiliensis, followed by lutjanids (five species), clupeids,
scombrids, mugilids (two species), and serranids. The invertebrates eaten
were mostly penaeid shrimp and some squid and nematodes. In east central
Florida, clupeids (principally the Spanish sardine, Sardinella aurita) were
the dominent fish prey. Other prey were anchovies, mullet, flying fish,
drum, and jacks. Squid was the major invertebrate food; others were
nematodes, penaeid shrimp, and isopods. Most fish eaten by adult king
mackerel were about the same size: 100 to 150 mm FL *44*.
COMMENTS ON JUVENILE FOOD -
King mackerel juveniles are primarily pelagic carnivores. Analysis of the
stomach contents of 84 juvenile king mackerel (103-309 mm FL) from Cape
Canaveral, 130 Spanish mackerel (117-432 mm FL) from Cape Canaveral, and 214
Spanish mackerel from Galveston Bay revealed that juveniles of both species
were principally piscivorous, but king mackerel showed a greater preference
for invertebrates. Anchovies (Anchoa spp.), menhaden (Brevoortia spp.), and
Atlantic thread herring (Opisthonema oglinum) were the dominent forage of
the mackerels. Much less common were mugilids, sciaenids, carangids, and
eleotrids. Squid was the major invertebrate prey for both species.
Juveniles fed heavily on anchovies, as shown by their frequencies of
occurrence (19-39%) and volume (30-54%) in mackerel stomachs. The body
shape of anchovies appears to make them highly suitable prey for juvenile
mackerel *44*.
Food Habits - 2 (DRAFT) - Environment Associations
Species mackerel, king
Species Id M010503
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: Specified in Comments
G
G
G
L
L
L
L Water Temperature: Greater than 27 degrees C
L Water Temperature: Between 21-27 degrees C
L Water Temperature: Specified in Comments
L Water Depth Preference: Specified in Comments
G Water Depth Preference: Specified in Comments
G Coastal Wetlands: Sounds and bays
G Estuarine habitat zone: offshore
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 44
REFERENCES FOR RESTING ADULT ENVIRONMENTAL ASSOC_ - 44
REFERENCES FOR BREEDING ADULT ENVIRONMENTAL ASSOC_ - 44
REFERENCES FOR RESTING JUVENILE ENVIRONMENTAL ASSOC_ - 44
REFERENCES FOR RESTING LARVAE ENVIRONMENTAL ASSOC_ - 44
REFERENCES FOR EGG ENVIRONMENTAL ASSOC_ - 44
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
TEMPERATURE: The northern range of the king mackerel extends only to the
20 deg C isotherm within the 18 m depth contour. The arrival of king
mackerel off west central Florida in the spring depends on changes in water
temperature and on the preceeding winter's air temperature. Futhermore,
sport catch data indicate that catch-per-hour is usually higher following
warm winters and lower following cold winters.
SALINITY: All life stages of king mackerel usually inhabit waters within
salinities of 32 to 36 ppt.
DEPTH: In the summer, large solitary king mackerel are sometimes captured
Environment Associations - 1 (DRAFT) - Environment Associations
Species mackerel, king
Species Id M010503
Date 27 AUG 96
off piers and near deepwater inlets.
HABITAT ZONE: King mackerel inhabit coastal waters and estuaries *44*.
COMMENTS ON RESTING ADULT ENVIRONMENTAL ASSOC_ -
TEMPERATURE: The northern range of the king mackerel extends only to the
20 deg C isotherm within the 18 m depth contour. The arrival of king
mackerel off west central Florida in the spring depends on changes in water
temperature and on the preceeding winter's air temperature. Futhermore,
sport catch data indicate that catch-per-hour is usually higher following
warm winters and lower following cold winters.
SALINITY: All life stages of king mackerel usually inhabit waters within
salinities of 32 to 36 ppt.
DEPTH: In the summer, large solitary king mackerel are sometimes captured
off piers and near deepwater inlets.
HABITAT ZONE: King mackerel inhabit coastal waters and estuaries *44*.
COMMENTS ON BREEDING ADULT ENVIRONMENTAL ASSOC_ -
HABITAT ZONE: King mackerel spawn in the coastal waters of the northern
Gulf of Mexico, and off the south Atlantic coast *44*.
COMMENTS ON RESTING JUVENILE ENVIRONMENTAL ASSOC_ -
SALINITY: All life stages of king mackerel usually inhabit waters within
salinities of 32 to 36 ppt *44*.
COMMENTS ON RESTING LARVAE ENVIRONMENTAL ASSOC_ -
TEMPERATURE: In the gulf, king mackerel larvae have been taken at
temperatures of 26 to 31 deg C, and in the south Atlantic at temperatures
of 22 to 28 deg C.
SALINITY: In the gulf, king mackerel larvae have been taken at surface
salinities from 27 to 36 ppt, and in the south Atlantic from 30 to 37 ppt.
DEPTH : King mackerel larvae were discovered off northwest Florida
and Texas between the Middle and Outer (35-183 m) Continental Shelf.
Larvae captured near Palm Beach, Florida, were closer to shore than those
captured farther north off Cape Canaveral, Florida, Savannah, Georgia, and
Cape Fear, North Carolina. North of Cape Canaveral, larvae were found
near or off the shelf along the 200 m depth contour and near the Gulf
Stream *44*.
COMMENTS ON EGG ENVIRONMENTAL ASSOC_ -
SALINITY: All life stages of the king mackerel usually inhabit waters
within salinities of 32 to 36 ppt *44*.
Environment Associations - 2 (DRAFT) - Life History
Species mackerel, king
Species Id M010503
Date 27 AUG 96
LIFE HISTORY
MORPHOLOGY/IDENTIFICATION AIDS: The elongated, fusiform, compressed body of
king mackerel is 4.25 to 5.00 times as long as the head, and 5.50 to 6.25
times as long as it is deep. They have two dorsal fins, the second followed
by 8 or 9 finlets. The lateral line, which abruptly curves downward below
the second dorsal fin, distinguishes the king mackerel from the Spanish
mackerel and cero mackerel (S. regalis). The caudal peduncle has a large
fleshy keel. The body is entirely scales with rudimentary scales, except
for most of the pectoral fin. The mouth is large and oblique with the
maxillary reaching posteriorly to slightly beyond the eye orbit. Each side
of the jaw has about 30 strongly compressed triangular teeth. This species
gets considerably larger than the Spanish mackerel.
SEASONAL DISTRIBUTION AND POPULATIONS: Extensive tagging studies indicate
that there are at least two migratory groups of king mackerel. Those tagged
in the winter south of Cape Canaveral, Florida, usually moved southward
through the Florida keys, entered the Gulf of Mexico in late winter and
spring, and then continued northward along the west Florida Continental
Shelf. Some were recaptured as far west as Texas and a few as far as
Veracruz and Yucatan, Mexico. These western migrants, some tagged off the
coasts of Texas and northwest Florida in the summer, returned to south
Florida in the winter.
A second group of king mackerel, tagged in the spring off southeast Florida,
moved northward in the summer along the Atlantic coast to the Carolinas.
One was recaptured as far north as Chincoteague, Virginia. King mackerel
tagged in South Carolina in the spring generally moved south in May through
August and were recaptured in Florida that summer. In the fall they
migrated to the northern limit of their distribution, and many were
recaptured in North Carolina.
Preliminary electrophoretic analysis of 48 enzymes extracted from king
mackerel tissues (heart, liver, eye, and muscle) give evidence that there
are two populations of king mackerel. Variation of two alleles for the
peptidase with glycylleucine-2 locus gave the greatest differences between
South Carolina and Texas specimens; however, other loci were minimally
polymorphic and of limited value for separating populations. Homing
tendencies are additional evidence of two populations. After a year or more
of freedom, king mackerel usually are recaptured at or near their release
site at about the same time of year they were first tagged.
SPAWNING: King mackerel spawn in the coastal waters of the Gulf of Mexico,
and off the south Atlantic coast. Because of a protracted spawning season,
larvae have been collected by sampling gear from May through October.
Catches were highest in September. The paucity of larvae in the eastern
Gulf of Mexico south of Cape San Blas, off the Yucatan Channel and southeast
Florida, indicates minimal spawning in these waters.
King mackerel larvae were discovered off northwest Florida and Texas between
the Middle and Outer (35-183 m) Continental Shelf. Larvae captured near
Palm Beach, Florida, were closer to shore than those captured farther north
off Cape Canaveral, Florida, Savannah, Georgia, and Cape Fear, North
Carolina. North of Cape Canaveral, larvae were found near or off the shelf
along the 200 m depth contour and near the Gulf Stream.
Further evidence of protracted spawning for king mackerel is the holding of
Life History - 1 (DRAFT) - Life History
Species mackerel, king
Species Id M010503
Date 27 AUG 96
vitellogenic eggs (eggs with forming yolk) from May through October.
Multiple spawning is suggested by bimodal distributions of mean oocyte
diameter of yolkbearing vitellogenic (stage 4) eggs. The first mode was in
late May through early July and the second was in late July and early
August. The appearance of spent males from September through December
coincided with a commensurate absence of vitellogenic eggs beginning in
August, suggesting a final climactic spawn.
MATURITY AND FECUNDITY: In south Florida, most male king mackerel probably
spawn in their fourth year of life (Age III) when about 718 mm FL; most
females spawn at Age IV when about 857 mm FL. Mature females about 600 mm
FL distributed from Texas to the Carolinas, with egg count estimates ranging
from 69,000 (446 mm FL, Age I, 0.68 kg) to 12,207,000 (1,489 mm FL, Age
XIII, 25.6 kg) were reported. The best indicator of fecundity is the total
weight of the fish.
EGGS, LARVAE, AND JUVENILES: Examination of Spanish and king mackerel
larvae 2.0 to 2.9 standard length (SL) offered diagnostic aids for
separating the larvae based on pigment (melanophore) differences in the jaw,
head, and nape areas. The myomere counts, fin elements, and pigmentation of
larger king mackerel larvae (3.3 to 17.0 mm SL) have been described, while
eggs have not yet been described.
Because most king mackerel larvae are collected near the surface, the
refinement of quantitative sampling techniques to collect larvae 3 mm SL
(about 3 days old) would aid in the delineation of spawning grounds. In the
gulf, mackerel larvae have been taken at surface salinities and temperatures
from 27 to 33 ppt and 26 to 31 deg C, and in the south Atlantic between 30
and 37 ppt and 22 to 28 deg C.
LONGEVITY AND GROWTH: Recent estimates of age, growth, and mortality of
king mackerel are probably more accurate than older ones because the
database includes more of the larger and older king mackerel collected from
North Carolina to Texas. The von Bertalanffy growth equation is as follows:
lt = Linfin (1 - exp(-K9t - to)))
where lt is length at age t, Linfin is asymptotic length, K is the growth
coefficient, and to is the age when the theoretical length is zero.
King mackerel were aged using otoliths. Although there was good correlation
between the growth of otoliths and length of fish, neither of two studies
clearly demonstrated that opaque otolith growth rings were valid indicators
of age.
Females live longer than males and usually grow faster after Age II. The
oldest females collected were 14 years of age or older: a 1.4 m FL fish
from Louisiana and a 90 lb (40.8 kg) fish from Key West. The oldest male
(979 mm SL) was 12 years old.
King mackerel growth is highly variable. For example, females 850 to 899 mm
FL could be 1 to 8 years old; males about the same size could be 3 to 8
years old. It has been suggested that compensatory growth occurs in "slow
growing" fish during their second year when their growth increment surpasses
that of "fast growers." Nevertheless, "slow growing" mackerel remain
smaller than "fast growers" throughout their lives.
Total annual mortality estimates were 0.37 (more recent) and 0.54.
FOOD HABITS:
Life History - 2 (DRAFT) - Life History
Species mackerel, king
Species Id M010503
Date 27 AUG 96
King mackerel juveniles and adults are primarily pelagic carnivores. They
feed mostly on schooling fish, secondarily on crustaceans, and minimally on
mollusks. The dominent prey by number (59%) were clupeids (Atlantic thread
herring) and scaled sardines, Harengula jaguana. The minor fish prey (8%)
were species of Carangidae, Lutjanidae, Pomadasyidae (Haemulidae), Sparidae,
and Triglidae. Invertebrates, particularly squid and shrimps, made up 33%
of the diet.
In south Florida, the king mackerel fed primarily on the ballyhoo,
Hemiramphus brasiliensis, followed by lutjanids (five species), clupeids,
scombrids, mugilids (two species), and serranids. The invertebrates eaten
were mostly penaeid shrimp and some squid and nematodes. In east central
Florida, clupeids (principally the Spanish sardine, Sardinella aurita) were
the dominent fish prey. Other prey were anchovies, mullet, flying fish,
drum, and jacks. Squid was the major invertebrate food; others were
nematodes, penaeid shrimp, and isopods. Most fish eaten by adult king
mackerel were about the same size: 100 to 150 mm FL.
King mackerel juveniles are primarily pelagic carnivores. Analysis of the
stomach contents of 84 juvenile king mackerel (103-309 mm FL) from Cape
Canaveral, 130 Spanish mackerel (117-432 mm FL) from Cape Canaveral, and 214
Spanish mackerel from Galveston Bay revealed that juveniles of both species
were principally piscivorous, but king mackerel showed a greater preference
for invertebrates. Anchovies (Anchoa spp.), menhaden (Brevoortia spp.), and
Atlantic thread herring (Opisthonema oglinum) were the dominent forage of
the mackerels. Much less common were mugilids, sciaenids, carangids, and
eleotrids. Squid was the major invertebrate prey for both species.
Juveniles fed heavily on anchovies, as shown by their frequencies of
occurrence (19-39%) and volume (30-54%) in mackerel stomachs. The body
shape of anchovies appears to make them highly suitable prey for juvenile
mackerel.
PREDATORS: Larvae and juveniles of king mackerel have been identified as
prey for the little tunny, Euthynnus alletteratus, and dolphin, Coryphaena
hippurus. Relatively large king mackerel are eaten by pelagic sharks,
little tunny, and dolphins. The bottlenose dolphin Tursiops truncatus
interferes with commercial fishing by pirating king mackerel hooked on
trolling lines and in nets. Sharks sometimes interfere with gill net sets
by eating mackerel caught in the mesh. The most common shark species are
the tiger shark, Galeocerdo cuvieri; bull shark, Carcharhinus leucas;
dusky shark, C. obscurus; smooth hammerhead, Sphyrna zygaena; shortfin
mako, Isurus oxyrinchus; lemon shark, Negaprion brevirostris; and
porbeagle, Lamna nasus *44*.
LIFE HISTORY CODES -
Foraging Sites: Standing water: Profundal zone
Average Number of Offspring/Reproductive Effort: Grea
REFERENCES FOR LIFE HISTORY- 44
Life History - 3 (DRAFT) - Management Practices
Species mackerel, king
Species Id M010503
Date 27 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Existing Regulating harvest of species being described
Existing Regulating commercial harvest gear types
Existing Regulating commercial harvest levels
Beneficial Developing/maintaining/protecting wetlands
REFERENCES FOR BENEFICIAL MANAGEMENT PRACTICES - 44
REFERENCES FOR EXISTING MANAGEMENT PRACTICES - 44
COMMENTS ON MANAGEMENT PRACTICES -
The Fishery Management Plan (FMP) for coastal pelagic fish species,
including mackerel, was implemented in March 1983 by the Gulf of Mexico and
South Atlantic Fishery Management Councils (GM&SAFMC). Quotas based on
theoretical yields partitioned according to historical landings were
established for the commercial hook-and-line (3,877,200 lb), net (5,122,800
lb), and sport (28,000,000 lb) fisheries, and were in effect from 1 July
1982 to 30 June 1983. In May 1983, the commercial hook-and-line fisheries
was officially closed when that quota was attained. This early closure was
attributed to increased catches in North Carolina (0.7 million lb) and
Louisiana (1.2 million lb). These new developments in conjunction with
decreasing catches in south Florida are currently under review by the
GS&ASMFC. Recent studies suggest that increased catches are related to
strong year classes, that more than one migratory group exists, and that a
maximum sustainable yield of 37.7 million lb may have been overestimated
*44*.
Excessive alterations of estuaries could reduce the production of coastal
forage fish on which king mackerel feed.*44*
The commercial fishery for Gulf group king mackerel in the eastern zone was
closed effective January 4, 1991. The closure was necessary to protect the
overfished Gulf king mackerel resource and is in compliance with the Fishery
Management Plan for Coastal Migratory Pelagic Resources of the Gulf of
Mexico and South Atlantic (FMP). The closure applies to federal waters (the
exclusive economic zone or EEZ), as defined by seasonal boundaries of the
Gulf migratory group, through June 30, 1991.*262*
Management Practices - 1 (DRAFT) - References
Species mackerel, king
Species Id M010503
Date 27 AUG 96
References
44* Godcharles, M.F., and M.D. Murphy. 1986. Species profiles: life
histories and environmental requirements of coastal fishes and
invertebrates (south Florida) -- king mackerel and Spanish mackerel. U.S.
Fish Wildl. Serv. Biol. Rep. 82(11.58). U.S. Army Corps of Engineers, TR
EL-82-4. 18 pp.
References - 1