(DRAFT) - Taxonomy
Species ladyfish
Species Id M010405
Date 27 AUG 96
TAXONOMY
NAME - ladyfish
OTHER COMMON NAMES - bigeyed herring, bony-fish, Chiro, Francesca, John Mariggle, Liza, matajuelo real, piojo, skipjack and tenpounder
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Chordata,
CLASS AND SUBCLASS - Osteichthyes,
ORDER AND SUBORDER - Elopiformes,
FAMILY AND SUBFAMILY - Elopidae,
GENUS AND SUBGENUS - Elops,
SPECIES AND SSP - saurus,
SCIENTIFIC NAME - Elops saurus
AUTHORITY - Linnaeus
TAXONOMY REFERENCES - 223
Taxonomy - 1 (DRAFT) - Status
Species ladyfish
Species Id M010405
Date 27 AUG 96
STATUS
Coded Status
Sport Fish
REFERENCES FOR STATUS - 223
COMMENTS ON STATUS -
The ladyfish is sought by anglers for its sporting attributes. It is
considered inedible in the United States because of the boniness of the
flesh, and therefore does not support commercial fisheries.*223*
Status - 1 (DRAFT) - Distribution
Species ladyfish
Species Id M010405
Date 27 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
HABITAT - MARINE
REFERENCES FOR HABITAT - 64
LAND USE -
Bays and Estuaries
REFERENCES FOR LAND USE - 64
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Marine OW0
Marine OW0 7
Marine OW0 7
Estuarine
Riverine
REFERENCES FOR NWI - 223
COMMENTS ON HABITAT ASSOCIATIONS -
Young ladyfish larvae are captured offshore. Older larvae and juveniles
inhabit coastal beaches, canals, bayous, lagoons, tidal ponds, creeks,
rivers, and mosquito control impoundments.*223*
Habitat Associations - 1 (DRAFT) - Food Habits
Species ladyfish
Species Id M010405
Date 27 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
OTHER
REFERENCES FOR TROPHIC LEVEL - 223
LIFESTAGE FOOD FOOD PART
Larva Zooplankton Not Applicable
Larva Insects Not Specified
Larva Fish Not Specified
Larva Copepods Not Specified
Larva See Comments; Food
Juvenile Zooplankton Not Applicable
Juvenile Insects Not Specified
Juvenile Fish Not Specified
Juvenile Crustaceans Not Specified
Juvenile Copepods Not Specified
Juvenile See Comments; Food
Adult Fish Not Specified
Adult Crustaceans Not Specified
Adult See Comments; Food
REFERENCES FOR ADULT FOOD - 223
REFERENCES FOR JUVENILE FOOD - 223
REFERENCES FOR LARVAE FOOD - 223
COMMENTS ON FOOD -
Stage I ladyfish larvae do not forage; nutrients are obtained directly from
seawater by integumentary absorption.*223*
In laboratory settings, early Stage II ladyfish larvae ate live plankton
and live brine shrimp (Artemia) nauplii. Stage III larvae ate small live
Fundulus and Gambusia and pieces of shrimp and fish. Under natural
conditions, Stage II and III ladyfish larvae (<50mm SL) feed almost
exclusively on zooplankton; consumption of zooplankton by juveniles is
progressively reduced as ingestion of small fishes and shrimps increases.
Ladyfish <100 mm long feed especially on insects, copepods, and other
arthropods.*223*
Adult ladyfish are strictly carnivorous and feed primarily on mid-water
prey. Food is swallowed whole.*223*
Adult ladyfish feed primarily on fish.*223*
Food Habits - 1 (DRAFT) - Food Habits
Species ladyfish
Species Id M010405
Date 27 AUG 96
COMMENTS ON ADULT FOOD -
Adult ladyfish are strictly carnivorous and feed primarily on mid-water
prey. Food is swallowed whole.*223*
Adult ladyfish feed primarily on fish.*223*
COMMENTS ON JUVENILE FOOD -
Consumption of zooplankton by juveniles is progressively reduced as
ingestion of small fishes and shrimps increases. Lady fish <100 mm long
feed especially on insects, copepods, and other arthropods.*223*
COMMENTS ON LARVAE FOOD -
Stage I ladyfish larvae do not forage; nutrients are obtained directly from
seawater by integumentary absorption.*223*
In laboratory settings, early Stage II ladyfish larvae ate live plankton
and live brine shrimp (Artemia) nauplii. Stage III larvae ate small live
Fundulus and Gambusia and pieces of shrimp and fish. Under natural
conditions, Stage II and III ladyfish larvae (<50mm SL) feed almost
exclusively on zooplankton; consumption of zooplankton by juveniles is
progressively reduced as ingestion of small fishes and shrimps increases.
Ladyfish <100 mm long feed especially on insects, copepods, and other
arthropods.*223*
Food Habits - 2 (DRAFT) - Environment Associations
Species ladyfish
Species Id M010405
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
L Water Temperature: Specified in Comments
A Water Temperature: Specified in Comments
L
J
A
A Dissolved Oxygen: Specified in Comments
L Turbidity: Clear water
A Turbidity: Murky water [High turbidity]
J Turbidity: Murky water [High turbidity]
J Water pH: Between 6.5-8.5
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 223
REFERENCES FOR ADULT ENVIRONMENTAL ASSOC_ - 223
REFERENCES FOR JUVENILE ENVIRONMENTAL ASSOC_ - 223
REFERENCES FOR LARVAE ENVIRONMENTAL ASSOC_ - 223
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Ladyfish are distinctly thermophilic fish. They have been reported in
cold-related fish kills in Florida.*223*
Early Stage I ladyfish larvae occur only in warm ocenaic waters (22.2-30.0
degrees C), and it appears probably that such temperatures are necessary
for proper development of eggs and early larvae.*223*
Ladyfish have been collected at tmeperatures of 11.0 to 35.0 degrees C.*223*
Throughout most of its life stages, ladyfish tolerate a wide range of
salinities. However, early Stage I larvae have been collected only at
oceanic salinities of 28.5-39.0 ppt, and it is likely that such
concentrations are required by eggs, yolk-sac larvae, and early Stage I
larvae of ladyfish for proper development.*223*
Beyond Stage I, ladyfish are decidedly euryhaline.223
Adult ladyfish tolerate a wide range of salinities; however literature does
not report adults living in truly freshwater.*223*
Environment Associations - 1 (DRAFT) - Environment Associations
Species ladyfish
Species Id M010405
Date 27 AUG 96
Dissolved oxygen requirements of ladyfish are unknown, but it is likely
that the species is relatively tolerant of hypoxic conditions, as it is
often found with tarpon in poorly oxygenated habitats. Ladyfish inhabit a
coastal impoundment in Louisiana in which dissolved oxygen concentrations
reached a minimum of 1.0 mg/l.*223*
Aerial spraying and ground fogging for nuisance insect control are widely
practiced in Florida's coastal zone, and agricultural pesticides and
herbicides used in south Florida enter coastal waters. Ladyfish are
extremely susceptible to contaminants. Application of dieldrin pellets in
a Florida salt marsh for the control of larval sandflies (Culicoides)
resulted in mortality of ladyfish.*223*
Stage I larvae of ladyfish occur only in clear offshore waters. Subsequent
life history stages apppear to be tolerant of high turbidities. Habitats
occupied, especially by juveniles, are generally described as turbid and
dark-stained.*223*
COMMENTS ON ADULT ENVIRONMENTAL ASSOC_ -
Ladyfish are distinctly thermophilic fish. They have been reported in
cold-related fish kills in Florida.*223*
Ladyfish have been collected at temperatures of 11.0 to 35.0 degrees C.*223*
Beyond Stage I, ladyfish are decidedly euryhaline.223
Adult ladyfish tolerate a wide range of salinities; however literature does
not report adults living in truly freshwater.*223*
Dissolved oxygen requirements of ladyfish are unknown, but it is likely
that the species is relatively tolerant of hypoxic conditions, as it is
often found with tarpon in poorly oxygenated habitats. Ladyfish inhabit a
coastal impoundment in Louisiana in which dissolved oxygen concentrations
reached a minimum of 1.0 mg/l.*223*
Aerial spraying and ground fogging for nuisance insect control are widely
practiced in Florida's coastal zone, and agricultural pesticides and
herbicides used in south Florida enter coastal waters. Ladyfish are
extremely susceptible to contaminants. Application of dieldrin pellets in
a Florida salt marsh for the control of larval sandflies (Culicoides)
resulted in mortality of ladyfish.*223*
Adult ladyfish apppear to be tolerant of high turbidities. Habitats
occupied are generally described as turbid and dark-stained.*223*
COMMENTS ON JUVENILE ENVIRONMENTAL ASSOC_ -
Beyond Stage I, ladyfish are decidedly euryhaline.223
Juvenile ladyfish apppear to be tolerant of high turbidities. Habitats
occupied by juveniles, are generally described as turbid and
dark-stained.*223*
Environment Associations - 2 (DRAFT) - Environment Associations
Species ladyfish
Species Id M010405
Date 27 AUG 96
COMMENTS ON LARVAE ENVIRONMENTAL ASSOC_ -
Early Stage I ladyfish larvae occur only in warm ocenaic waters (22.2-30.0
degrees C), and it appears probably that such temperatures are necessary
for proper development of eggs and early larvae.*223*
Throughout most of its life stages, ladyfish tolerate a wide range of
salinities. However, early Stage I larvae have been collected only at
oceanic salinities of 28.5-39.0 ppt, and it is likely that such
concentrations are required by eggs, yolk-sac larvae, and early Stage I
larvae of ladyfish for proper development.*223*
Stage I larvae of ladyfish occur only in clear offshore waters.*223*
Environment Associations - 3 (DRAFT) - Life History
Species ladyfish
Species Id M010405
Date 27 AUG 96
LIFE HISTORY
MORPHOLOGY: The ladyfish is herring-like in general appearance but is
readily distinguished from clupeids by the presence of an elongate bony
angular plate between the branches of the lower jaw and a much larger mouth;
the jaw extends considerably posterior to the rear edge of the orbit. The
belly is not keeled or serrated as in herrings, but is relatively broad and
covered with ordinary scales.*223* The following description of the Elopidae
is summarized from Jordan and Evermann (1969). Body elongate, somewhat
compressed, and covered with silvery cycloid scales. No scales on head.
Lateral line present. Mouth broad, lower jaw prominent. Premaxillaries short
and nonprotactile; maxillaries form lateral margins of the upper jaw. Eye
relatively large, with adipose eyelid. Bands of villiform teeth on jaws,
vomer, palatines, pterygoids, tongue, and base of skull. Opercular bones
thin, with expanded membranous margins. Gill membranes entirely separate and
free from the isthmus; gillrakers long and slender. Dorsal fin inserted over
or slightly behind the pelvics. Caudal fin forked, dorsal and anal fins
depressible into scaly sheaths. No spines or adipose fin. Very long
accessory scales at the pectorals and pelvics.*223*
Body very elongate and covered with small, thin, silvery scales. Head small and pointed, with very
large terminal mouth; maxillary reaches far behind eye. Branchiostegal rays
30. Dorsal fin inserted slightly behind the pelvics. Dorsal, anal, and
pelvic fin ray counts, 20, 13, and 15, respectively. Caudal lobes long and
slender. Lateral line straight, with simple pores, 110 to 120 scales. Color
silvery all over and bluish dorsally, with lower parts of sides and ventral
surface yellowish or white. Dorsal and caudal fins dusky yellowish and
silvery. Pelvics and pectorals speckled, yellowish, and dusky. Reaches a
maximum length of about 1 m (usually less than 60 cm) and weight of several
kilograms.*223* This species can be easily distinguished from the tarpon.
The ladyfish has large pseudobranchs and small scales. The last ray of the
dorsal is not elongated, and the anal fin is smaller than the dorsal.*223*
REPRODUCTION: Spawning locations of ladyfish are unknown, but have been
inferred to be offshore throughout most of the range of the species, as
judged by the locations of capture of early larvae.*223*
Spawning of ladyfish appears to extend throughout most of the year, perhaps
peaking in fall, as judged by the occurrence of Stage I larvae.*223*
BEHAVIOR: Stage I ladyfish larvae do not forage; nutrients are obtained
directly from seawater by integumentary absorption.*223*
Adult ladyfish are strictly carnivorous and feed primarily on mid-water
prey. Food is swallowed whole.*223*
LIMITING FACTORS: Predation by carnivorous zooplankters and small fishes
undoubtedly causes high mortality of eggs and larvae of ladyfish before the
larvae enter coastal nursery marshes. Ladyfish are probably preyed upon by
piscivorous birds.*223*
Trematodes of the genera Bucephalus and Prosorhynchus have been reported
from the intestine of ladyfish.*223*
Life History - 1 (DRAFT) - Life History
Species ladyfish
Species Id M010405
Date 27 AUG 96
POPULATION ATTRIBUTES:
GROWTH Post yolk-sac larval development in ladyfish progresses through three
distinct stages. Stage I is an initial period of length increase that
culminates in the development of a fully formed leptocephalus larva. The
leptocephalus is characterized by a long, ribboon-like, colorless,
transparent body; large fang-like teeth; a very small head; and small fins.
It lacks gills and red blood cells, and its gut is not open. Oxygen and
nutrients are absorbed through the skin. In Stage II, the larva decreases
markedly in length and gradually loses the ribbon-like leptocephalic
morphology. Stage III is a second period of length increase that terminates
with the beginning of the juvenile stage. Late in Stage II and throughout
Stage III the larva undergoes pronounced changes in body form, including
increases in body depth, snout length, head length, dorsal and anal fin
height, and pectoral fin size. Late in Stage III, the body starts to become
opaque and silvery. Juveniles resemble adults in general appearance.*223*
Researchers reared ladyfish in the laboratory from early Stage II to the
juvenile phase. Rates of change in standard length during the first part of
Stage II (from about 35-40 mm to 25 mm SL) averaged -1.061 mm/day. Further
shrinking to about 20-21 mm SL proceeded at about -0.342 mm/day. Initial
length increase during early Stage III, from about 20 to 25 mm SL, averaged
0.140 mm/day. Growth rates of late Stage III larvae and early juveniles
(<60 mm SL) were about 0.626 mm/day. Larger juveniles grew an average of
0.628 mm/day. Field collections suggested a faster rate of growth (about 2
mm/day) under natural conditions. No information is available on growth of
adult ladyfish.*223*
LIFE HISTORY CODES -
Breeding/Spawning Season: January
Breeding/Spawning Season: February
Breeding/Spawning Season: March
Breeding Spawning Season: April
Breeding/Spawning Season: May
Breeding/Spawning Season: June
Breeding/Spawning Season: July
Breeding/Spawning Season: August
Breeding/Spawning Season: September
Breeding/Spawning Season: October
Breeding/Spawning Season: November
Breeding/Spawning Season: December
Display Site: Water
REFERENCES FOR LIFE HISTORY- 223
Life History - 2 (DRAFT) - Management Practices
Species ladyfish
Species Id M010405
Date 27 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Adverse Shoreline modification/development
Adverse
Adverse Constructing/maintaining bulkheads, seawalls, and dikes
Adverse Locating/constructing powerlines and other rights-of-way
Existing Other management practices [specified in comments]
REFERENCES FOR ADVERSE MANAGEMENT PRACTICES - 223
REFERENCES FOR EXISTING MANAGEMENT PRACTICES - 223
COMMENTS ON MANAGEMENT PRACTICES -
Offshore and coastal habitats of very young adult ladyfish are relatively
immune to human-induced degradation. Conversely, the estuaries, salt
marshes, and coastal mangroves used as nurseries by larval and juvenile
ladyfish in Florida are highly vulnerable to changes induced by development.
Factors resulting in the destruction of nursery wetlands include
filling of wetlands, canalization, bulkheading, construction of water-line
right-of-ways and steep-sided boat-access finger-canals, and impoundment of
wetlands for mosquito control. Progress has recently been made in
ameliorating the effects of impoundment for mosquito control because
impoundment does not necessarily result in the destruction of wetlands.
Rather, impounded wetlands, if properly managed, can retain the beneficial
characteristics of natural wetlands while providing adequate mosquito
control. However, access to these wetlands (and subsequent opportunities
for egress) by larval and juvenile ladyfish is precluded or severely
curtailed by reduced or non-existent exchange with estuarine waters.
Improved impoundment management strategies, aimed at enhancing exchange
rates, have been proposed.*223*
Management Practices - 1 (DRAFT) - References
Species ladyfish
Species Id M010405
Date 27 AUG 96
References
223 * Zale, A.V. 1989. Species Profiles: Life Histories and
Environmental Requirements of Coastal Fishes and Invertebrates
(South Florida) - Ladyfish and Tarpon. 82(11.104) (ed.).
National Wetlands Research Center Washington, DC:17.
References - 1