REFEJtEPdCE COPY 

Do Not Remove from the Library 

U. S. Fish and Wildlife Service 

Biological Report 82 (1 1-34) National wetiarld3 -n"r 

April 1985 700 Cajun Dome Boulevard TR EL.82-4 

Lafayette, Louisiana 70506 

Species Profiles: Life Histories and 

Environmental Requirements of Coastal Fishes 

and Invertebrates (South Florida) 

STRIPED MULLET 

Coastal Ecology Group Fish and Wildlife Service Waterways Experiment Station 

U.S. Department of the Interior U.S. Army Corps of Engineers 
This is one of the first reports to be publ ished in the new "Biological 

Report" series. This technical report series, publ i shed by the Research 

and Development branch of the U.S. Fish and Wildlife Service, replaces 

the "FWS/OBS1' series published from 1976 to September 1984. The Biological Report series is designed for the rapid publication of reports with 

an application orientation, and it continues the focus of the FWS/OBS 

series on resource management issues and fish and wildlife needs. 
Biological Report 82(11.34) 

TR EL-82-4 

April 1985 

Species Profiles: Life Histories and Environmental Requirements 

of Coastal Fishes and Invertebrates (South Florida) 

STRIPED MLILLET 

Mark R. Coll ins 

Department of Zoo1 ogy 

University of Florida 

Gainesville, FL 32611 

Project Manager 

Larry Shanks 

Project Officer 

John Parsons 

National Coastal Ecosystems Team 

U.S. Fish and Wildlife Service 

1010 Gause Boulevard 

Sl i dell, LA 70458 

Performed for 

Coastal Ecology Group 

Waterways Experiment Station 

U.S. Army Corps of Engineers 

Vicksburg, MS 39180 

and 

National Coastal Ecosystems Team 

Division of Biological Services 

Research and Development 

Fish and Wild1 ife Service 

U.S. Department of the Interior 

Washington, DC 20240 
This series should be referenced as follows: 

U.S. Fish and Wildlife Service. 1983-19 . Species profiles: life histories and 

environmental requirements of coasta'i- fishes and invertebrates. U. S. Fish 

Wildl. Serv. Biol. Rep. 82(11). U.S. Army Corps of Engineers, TR EL-82-4. 

This profile should be cited as follows: 

C o l l i n s , M. R. 1985. Species profiles: 1 ife histories and environmental 

requirements of coastal fishes and invertebrates (South Florida)--striped 

mullet. U.S. Fish Wildl. Serv. Biol. Rep. 82(11.34). U.S. Army Corps of 

Engineers, TR EL-82-4. 11 pp. 
PREFACE 

This species profile is one of a series on coastal aquatic organisms, 

principally fish, of sport, commercial , or ecological importance. The profiles 

are designed to provide coastal managers, engineers, and biologists with a brief 

csnprehensive sketch of the biol ogical characteristics and environmental requiremnts of the species and to describe how populations of the species may be 

eqected to react to environmental changes caused by coastal development. Each 

profile has sections on taxonomy, 1 i fe history, ecological role, environmental 

requirements , and economic importance, if appl icabl e. A three-ring binder is 

used for this series so that new profiles can be added as they are prepared. This 

project is jointly planned and financed by the U.S. Army Corps of Engineers and 

the U.S. Fish and Wildlife Service. 

Suggestions or questions regarding this report should be directed to one 

of the fol 1 owing addresses. 

Infomation Transfer Special ist 

National Coastal Ecosys tems Team 

U.S. Fish and Wildlife Service 

NASA-Sl idel 1 Computer Compl ex 

1010 Gause Boulevard 

Sl idel 1 , LA 70458 

U.S. Army Engineer Waterways Experiment Station 

Attention: WESER-C 

Post Office Box 631 

Vicksburg, MS 39180 
CONVERSION TABLE 

mil 1 imeters (mn) 

centimeters ( an) 

meters (m) 

ki 1 meters ( km) 

2 

square meters (m ) 

square ki 1 meters ( km2) 

hectares (ha) 

liters (1) 

cubic meters (m3) 

cubic meters 

mill igrams (mg) 

grams (g) kil ograms (kg) 

metric tons (t) 

metric tons 

ki 1 ocal ories ( kcal ) 

Cel s ius degrees 

Metric to U.S. Customary 

!Y To Obtain 

inches 

inches 

feet 

mi 1 es 

square feet 

square miles 

acres 

gal 1 ons 

cubic feet 

acre- feet 

0.00003527 ounces 

0.03527 ounces 

2.205 pounds 

2205.0 pounds 

1.102 short tons 

3.968 British thermal units 

1.8(OC) + 32 Fahrenheit degrees 

U.S. Customary to Metric 

inches 25.40 

i nches 2.54 

feet (ft) 0.3048 

fa thoms 1.829 

miles (mi) 1.609 

nautical miles (mi) 1.852 

square feet (ft2) 

acres 2 

square miles (mi ) 

gal 1 ons (gal ) 3.785 

cubic feet (ft3) 0.02831 

acre- feet 1233.0 

ounces (02) 28.35 

pounds (Ib) 0.4536 

short tons (ton) 0.9072 

British thermal units (Btu) 0.2520 

mil 1 imeters 

centimeters 

meters 

meters 

kil meters 

ki 1 meters 

square meters 

hectares 

square kilometers 

1 i ters 

cubic meters 

cubic meters 

grams 

ki 1 og rams 

metric tons 

ki 1 ocal ories 

Fahrenheit degrees 0.5556("F - 32) Celsius degrees 
CONTENTS 

PREFACE .................................................................. CONVERSION TABLE ......................................................... ACKNOWLEDGMENTS .......................................................... 

NOMENCLATLlRE/TAXONOMY/RANGE .............................................. MORPHOLOGY/IDENTIFICATION AIDS ........................................... REASON FOR INCLUSION IN SERIES ........................................... LIFE HISTORY ............................................................. Spawning ............................................................... Larvae and Juveniles ................................................... Adults ................................................................. GROWTH CHARACTERISTICS ................................................... FISHERIES ................................................................ Sport .................................................................. Commercial ............................................................. Management ............................................................. ECOLOGICAL ROLE .......................................................... ENVIRONMENTAL REQUIREMENTS ............................................... Temperature ............................................................ Salinity ............................................................... Dissolved Oxygen ....................................................... Depth .................................................................. 

LITERATURE CITED ......................................................... 

Page 

i i i 

i v 

v i 

1 

1 

3 

3 

3 

3 

4 

4 

5 

5 

5 

6 

6 

7 

7 

8 

8 

8 

9 
ACKNOWLEDGMENTS 

I am grateful for the review of the manuscript by J. Shireman of the University of Florida. 
Figure 1. Striped mullet. 

STRIPED MULLET 

Scientific name . . Mugil cephalus 

Li nnaeus 1758 

Preferred common name . . . striped 

mu1 let (Figure 1) 

Other common names . . . grey mu1 let, 

black mu1 let 

Class . . . . . . . . . . Osteichthyes 

Order . . . . . . . . . . Perciformes 

Family . . . . . . . . . . . Mugi 1 i dae 

Geographic Range: Coastal waters of 

a1 1 seas, roughly between 42' N and 

42' S. In the western Atlantic from 

Brazil to Nova Scotia (Hoese and 

Moore 1977). Abundant along the 

south Florida- coast (Figure 2). 

MORPHOLOGY/IDENTIFICATION AIDS 

Dorsal fin IV + I spines, 8 soft 

rays; anal fin I11 spines, 8 rays (11, 

9 in juveniles); pectoral fin 16-17 

rays; caudal fin 18-20 rays; lateral 

scale count 38-42. Anal and second 

dorsal fins a1 most scaleless; origin 

of second dorsal behind origin of anal 

fin; pectoral fin shorter than distance from last spine of first dorsal 

to origin of second dorsal fin; head 

somewhat wider than deep; mouth terminal and small, teeth inconspicuous; no 

1 ateral 1 i ne vi si bl e, but 1 ongi tudi nal 

dark stripes on the sides of elongate 

body; body bl ui sh-gray dorsally and 

white ventrally; scales cycloid in 

young, feebly ctenoid in adults; distinct axillary scale at pectoral fin; 

gill raker number increasing with 

size; prominent adipose eye1 id with 

only a narrow slit over the pupil, 

covering the preorbi tal anteriorly and 

running twice as far behind the eye as 

in front (Hoese and Moore 1977). The 

six Mugil species reported from south 

Florida sometimes are difficult to 

separate taxonomical ly; however Rivas 

(1980) constructed a key that is useful for tentative identification. The 

two species most often encountered, 

striped mullet and white mullet, may 

be separated by anal fin ray counts of 

8 and 9, respectively. 
T. PETERSBURG 

PALM BEACH 

CAPE ROMAN 

THOUSAND ISLAND 

MILES 

KILOMETERS 

Figure 2. Striped rnu1:Iet are distributed along the entire coast of the Southern 

Fl ori da Region. 

2 
REASON FOR INCLUSION IN SERIES 

Striped mullet, perhaps the most 

widespread and abundant inshore teleost (Odum 1970), supports a valuable 

commercial fishery along the gulf 

coast of Florida (Rivas 1980). Mullet 

are primary consumers that feed largely on relatively minute living and 

dead vegetable matter. They are an 

ecol ogical ly important component in 

the flow of energy through estuarine 

communities. In many parts of the 

world striped mu1 let are important in 

fish culture. 

LIFE HISTORY 

Spawning 

Because of the scarcity of data 

on striped mu1 1 et spawning, speculations on the locations of spawning 

grounds are based largely on the appearance of larvae. Mullet have been 

reported to spawn inshore (Breder 

19401, along beaches (Gunter 1945), 8 

to 32 km offshore (Broadhead 1953), 

and in water deeper than 40 m 

(Anderson 1958). In the Gulf of 

Mexico, mu1 1 et were observed spawning 

65 to 80 km offshore in water 1,000 to 

1,800 m deep (Arnold and Thompson 

1958). These observations indicate 

that mullet spawn over a wide range of 

coastal waters but the current consensus is that most spawn offshore. 

The spawning season of striped 

mu1 1 et usual ly begins in October, 

peaks in November-December, and ends 

in February (Anderson 1958; Ri-vas 

1980). Along Florida s west coast, 

striped mu1 1 et spawn from October 

through May at Cedar Key and from 

December through July at Bayport 

(Kilby 1949). In Australia some females spawn only in alternate years 

(Thomson 1955), and evidence from 

Louisiana (Shireman 1975) suggests 

this may a1 so be true for mu1 let in 

U .S. waters. The estimated fecundity 

of striped mullet is 0.5 to 2.0 million eggs per female, depending on the 

size of the female (Broadhead 1953). 

A fecundity value of 648 f 62 eggslg 

body wei ght was calculated by Shehadeh 

et al. (1973). 

Eggs are transparent, strawcolored, non-adhesive, spherical , and 

without external marking. The eggs 

average 0.72 mn in diameter, contain 

an oil globule 0.28 mn in diameter, 

are positively buoyant, and hatch 

about 48 h after fertilization 

(Thomson 1963 1. 

Larvae and Juveni 1 es 

Larvae average 2.4 mn long (all 

lengths in this report are total 

1 engths unl ess indicated otherwise) at 

hatching and have no mouth, paired 

fins, or branchial skeleton. After 5 

days they are about 2.8 mn long, the 

jaws are we1 1 -defined, the internal 

organs become organized, and fin' buds 

have started developing (Thomson 

1963). Morphological and. meristic 

development and growth continue until 

the larvae are about 16-20 nn standard 

length (SL), at which time they migrate to inshore waters and estuaries 

(Kilby 1949; Anderson 1958). The migrant larvae have two spines and nine 

rays in the anal fin (the "Querimana" 

stage) until they reach 35-45 mn SL, 

at which time the first ray fuses into 

a third spine and the adipose eye1 id 

becomes apparent. The mullet is then 

considered a juveni 1 e (Anderson 1958). 

Juvenile striped mlillet 40 to 69 

mn SL reach a "definitive state" of 

osmoregul atory capabi 1 i ty . For example, they tolerate salinities of 0 to 

35 ppt, whereas they could not have 

previously survived in freshwater. 

Juveniles spend the rest of their 

first year of life in coastal waters, 

salt marshes, and estuaries, and often 

move to deeper water in the fall when 

the adults migrate offshore to spawn, 

yet large nunbers of imnature mullet 

overwinter in estuaries. After the 

first year, mullet inhabit the sea, 

salt marshes, estuaries, or freshwater 

ri vers (Nordl ie et a1 . 1982). Appar- 
ently in some instances, females 

greatly outnumber the males in bracki sh and freshwater habitats (Shi reman 

1975; Col 1 ins 1981 1. 

Adul ts 

The length at which mullet mature 

ranges from about 20G to 300 m SL; 

the females mature at a slightly larger size than the males. A1 though some 

mature in their second year of life, 

most mature in their third year 

(Broadhead 1953, 1958; Ri vas 1980 ) . On the northern gulf coast of Florida, 

the growth rate and size at maturity 

of stri ped mu1 1 et increased progressively from west to east. Mullet may 

1 i ve 4 years or more (Rivas 1980) ; the 

maximum age reported is 13 years 

(Thomson 1963). 

Mature mullet migrate offshore to 

spawh in the fall and winter, often in 

large schools. Mullet that mature in 

freshwater either migrate to the sea 

to spawn or resorb their gonads 

(Shi reman 1975). Swi mi ng speed during migration is much greater than 

that predicted to be energetically 

optimal, probably because of the increased hydromechanical efficiency 

provided by school ing and the selecti ve force of heavy predation duri ng 

spawning migrations (Peterson 1976). 

Fishing for mullet is heaviest during 

spawning mi grati ons when school s are 

large, the condition of the fish is 

excel lent, and the prized roe (gonads) 

are largest. 

In a mullet tagging study, 2,779 

recoveries from 12,647 tagged mu1 1 et 

revealed that 91% were recovered within 32 km of the release point; only 2% 

were recovered more than 160 km 

away. These results together with 

other tagging studies and meristic 

analyses (Broadhead 1953; Broadhead 

and Mefford 1956; De Sylva et al. 

1956), indicate that Florida gulf 

coast mullet are divided into three 

1 oosely knit populations, the south 

Florida population extending northward 

to the Steinhatchee area. East coast 

mu1 let commonly mi grate much further 

(up to 560 km), usually in a southerly 

direction, and are considered a single population. Fish returning from 

spawning migrations on the gulf coast 

usually have less fat reserves and 

more eroded fins and lesions on the 

body than do premigratory mu1 let (M. R. 

Coll ins, University of Florida, 

Gainesville; unpublished data). 

GROWTH CHARACTERISTICS 

Growth rates of stri ped mu1 1 et 

along the gulf coast of Florida increase from west to east along the 

panhandle and to the south along the 

peninsula, possibly due to a slight 

increase in coastal water temperatures 

(Broadhead 1958). In a tagging study, 

Broadhead (1953) found that growth 

during spring and summer is twice that 

of fall and winter: 7.3 i. 1.8 

mm/quarter for the first and fourth 

quarters of the year, 16.4 i. 2.7 

mm/quarter for the second, and 19.1 f 

2.7 m/quarter for the third. The 

mean fork lengths of mu1 let from four 

gulf coast areas for each year of life 

are given in Table 1. 

Table 1. Mean fork lengths (mm) of 

striped mullet at various ages from 

four gulf coast areas of Florida as 

calculated from scale analysis 

(Broadhead 1958). 

Year of 1 ife 

Area 1 2 3 4 

Pensacola 142 207 263 -- 

Apalachicola 134 207 271 -- 

Cedar Key 175 258 307 -- 

Homosassa 178 269 319 366 
Females are larger and grow 

slightly faster than males of the same 

age (Broadhead 1958). In the Cedar 

Key and Crystal River areas, mullet 

longer than 28 cm SL are predominantly 

females (Collins 1981). In the Gulf 

of Mexico, the growth in length of 

mu1 let gradually slows as the fish 

become larger, and reaches an asymptote at an average length of 600 inn 

TL, at probably 5-6 years of age 

(Rivas 1980). Length-weight relationships for striped mullet in the gulf 

are given in Figure 3. 

FISHERIES 

Sport 

Striped mu1 let along the Florida 

gulf coast are used as bait for a wide 

variety of fishes and are regarded as 

an excellent food fish. In fresh and 

brackish waters, mu1 let are sometimes 

caught with hook and line. Earthworms 

may be used for bait, but oatmeal and 

chicken laying mash are more popular. Mullet from freshwater often 

have a muddy or hydrogen sulfide-like 

LLNOTH IN INCHES I I . 10 11 8, I, I. 11 <, LIIIIIIIII 

1'" I. BOTH SEXES NOT SPAWNIN0 I ,I 

2. FEMALES SPAWNlNO 

I. MALE SPAWNING "'t BOO , I:::; 

l~~~~x~~~~~.~~~~~.~

"""-"""""""""""".."-"" ". 'zcP.;:::.:;:~"-"... ""' " "I....""." ". LENGTH IN MU. 

Figure 3. Length-weight re1 ationships 

of striped mullet from Florida's gulf 

coast in 1951 (Broadhead 1953). 

taste. In brackish and saltwater 

areas, mu1 let are sometimes snagged 

with treble hooks, but most often some 

type of net is used. Sport fishermen 

usually use a cast net or seine, but 

some use short lengths of gill nets or 

tranel nets. 

Coinnercial 

In general, sport and commercial 

mu1 let fishermen employ the same types 

of nets, but commercial seines, gill 

nets, and trammel nets are usually 

much longer. Seines are now used more 

on the east coast than on the west 

coast because of the abundance of 

smooth bottoms near sandy beaches on 

the east coast. Nets with largest 

meshes are used in the fall when mullet are gravid and fat. Many gill 

nets and trammel nets are longer than 

500 m and are usually set from a 

boat. When mullet are in open water 

either net is set to completely encircle the school; when the school is 

near a shoreline the net is set in a 

half-circle from shore to shore; and 

in intertidal coves or creeks the nets 

are used to completely block off an 

area, catching the mullet as they 

leave with the ebb tide. Fishing may 

be carried out day or night, and sometimes two boats work together, 

combining their nets and encircling a 

school from opposite d i r e c t i ons. When 

seines or nets are used, many mullet 

escape by jumping over the float line 

and, in the case of gill and tranel 

nets, they may avoid the net. Small 

mullet escape through the mesh. 

The commercial landings of mu1 let 

were not reported by species until 

1958. Since then, Florida has produced 80% to 90% of the U.S. striped 

mullet catch from the Gulf of Mexico 

(Rivas 1980). The annual Florida 

catch of striped mu1 1 et in 1958-1981 

fluctuated from a high of 35 mil lion 

Ib in 1964 to a low of 16.8million 1b 

in 1976 (Table 2). Gulf coast landings contributed about 80% of the 

catch. Mullet also are important 

baitfish, especially in the sport 
Table 2. Annual catch of striped 

mu1 let (mi 11 ions of pounds) in Florida, 1958-81. Data compiled from 

annual catch statistics, National 

Marine Fisheries Service, Washington, 

D. C. 

Year Catch Year Catch Year Catch 

ly, minimum lengths of 9 to 11 inches 

FL (depending on local ordinances) are 

the only regulations (Rivas 1980). 

A1 though 1 andi ngs and fishing i ntensi - 

ty for striped mullet declined from 

1964 to 1977, catch-per-unit-of-effort 

and the average size of the fish remained unchanged. This relationship 

suggests that the lack of demand 

rather than a scarcity of mullet limits the fishing (Rivas 1980). 

ECOLOGICAL ROLE 

fishery for bil lfi sh. They commonly 

bring a higher price as bait than as 

food fish. 

Most (65%) striped mullet are 

marketed in the Southeast United 

States. The remainder are marketed in 

1 arge northeastern, mi dwestern, and 

Cal ifornia cities. Of the total 

catch, about 25% is marketed fresh, 

63% frozen in the round, 6% smoked, 

and 6% as roe. Marketing in other 

forms has been attempted, but failed 

because mu1 1 et turn rancid within 60 

days and consumer acceptance is poor 

outside of the southeast (Cato et al. 

1976; Rivas 1980). 

Management 

Closed seasons and other regulations have been used to manage the 

Florida mullet in the past, but most 

have si nce been el imi nated. CurrentThere has been some discrepancy 

concerning the diet of juvenile 

striped mullet but most authors now 

agree that larval mullet primarily eat 

microcrustaceans (De Sil va 1980). The 

fact that 1 arvae, successfully reared 

to 20 mn SL, were fed entirely on 

animal material i 11 ustrates the dependence of larval and postlarval mu1 let 

on zooplankton (Nash et al. 1974). In 

Florida's Indian River lagoon the 

stomach contents of nearly 400 stri ped 

mullet larvae up to 35 mn SL were 

examined. Larvae up to 15 mn SL fed 

almost entirely on copepods (70%) and 

mosquito larvae (30%); those from 15 

to 25 mn SL fed on copepods (SO%), 

mosquito larvae (1581, and plant debris (35%); and larvae from 25 to 35 

mn SL fed primarily on plant debris 

(80%) and copepods (10%) (Harri ngton 

and Harri ngton 1961 1. The proportion 

of sand and detritus in the gut of 

juveniles increases with length, indicating that they tend to take more 

food from the bottom as they grow 

older (De Silva and Wijeyaratne 

1977). The exceptions are juveniles 

that feed from the water column or 

surface when suitable foods are plentiful there. For example, in one 

study mullet 35-80 mn long fed on a 

bl oom of the di nof 1 age1 1 ate Kryptoperidinium sp. (Odum 1968). The rate 

of digestfon or retention time of food 

in juveniles varies with both salinity 

and body weight. In Sri Lanka, a 

study of juvenile mu1 let 10 to 50 mn 

long showed that digestion rate increases with body weight and that both 
digestion and ingestion rates increased with salinity from 1 ppt to 30 

ppt (Perera and De Silva 1978). Food 

evacuation times ranged from about 

three to six hours. 

Adult striped mu1 let have been 

described as herbivorous, detritivorous, and "interface" feeders. 

The diet and feeding behavior of 

mullet may vary by location, but their 

major food is either epiphytic and 

benthic microal gae, macrophyte detri - 

tus, or inorganic sediment particles. A1 though sediment parti cles 

function as a grinding paste in the 

gizzard-like pyloric portion of the 

stomach, some small particles are rich 

in adsorbed micro-organi sms and are 

selectively ingested for their food 

val ue (Odum 1970 ) . 

Mullet commonly feed by sucking 

up the top layer of sediment, which is 

rich in detritus and microalgae, primarily diatoms in the Cedar Key area 

(Collins 19811, and by grazing on 

epiphytes and epi fauna from seagrasses 

and other substrates. They also ingest surface scum when large concentrations of microalgae are present at 

the air-water interface (Odum 1970), 

and feed on swarming polychaetes 

(Nereis succinea) in the water column 

and MigTarese 1978). In some 

freshwater habitats striped mu1 1 et 

feed primarily on the epiphytes and 

epifauna of aquatic macrophytes and on 

benthic filamentous green algae 

(Coll ins 1981 1, but they also ingest 

sediment for tri turation (grinding). 

The time of most intense feeding apparently varies with location. In all 

Florida habitats studied by Odum 

(1970) feeding varied with the height 

of the tide, whereas in saltwater 

(Cedar Key) and freshwater (Crystal 

River) sites studied by Collins (1981) 

feeding was strictly diurnal and unrelated to tidal stage. 

The major predators of juvenile 

and adult mullet are fishes and birds 

(Thomson 1963). In Florida, sharks 

sometimes feed heavily on large mullet. Mu1 let up to 35 cm long are fed 

on by spotted seatrout (Cynoscion 

nebulosus) (Breuer 1957). A1 thougT 

the diet of striped mullet overlaps 

those of a variety of aquatic species, 

competition has not been documented. 

Parasitic infections and infestations are common in mu1 let. Of nearly 

300 adult mu1 let from freshwater and 

saltwater sites on Florida's gulf 

coast, no individuals were found without parasites on either the gills or 

body surface (M. R. Collins, Univ. of 

Fla., Gainesvil le; unpubl i shed 

data). Striped mullet serve as defi ni ti ve or intermediate hosts for 

many parasites including fl age1 1 ates, 

ci 1 iates, myxospori di ans, monogenean 

and di genean trematodes, nematodes, 

acanthocephalans, leeches, argul ids, 

copepods, and isopods (Paperna 1975; 

Overstreet 1978; Paperna and Overstreet 1981 ). Extensive parasiteinduced mortalities of mu1 let in the 

wild have not apparently been reported. 

ENVIRONMENTAL REQUIREMENTS 

Temperature 

An analysis of the worldwide 

distribution of striped mu1 let suggests that mullet are not permanent 

resi dents i n waters with temperatures 

below 16O~ or where water temperatures 

fail to reach 18O~. On Florida's gulf 

coast, young striped mullet live in 

salt marsh pool s at temperatures from 

13O~ to 34.5'~ (Kilby 1949). Water 

temperatures probably regulate the 

length of time that young mullet stay 

in estuaries. Mullet less than 50 mn 

SL prefer temperatures from 30.0° to 

32.5O~ and mu1 let from 50 to 130 mn SL 

prefer temperatures from 19.5~ to 

20.0~~. For all sizes of fish the 

temperature selected tends to decrease 

as salinity increases. In experiments 

with Hawaiian striped mu1 let 78-122 mn 

SL, the upper lethal tem erature was oP between 27.0~ and 29.6 C for fish 

acclimated at 21°c in freshwater and 
the lower lethal tem erature was be- g tween 10.2~ and 15.0 C (Sylvester et 

a1 . 1974). The upper 1 ethal tem era- I ture for mullet acclimated at 26 C in 

saltwater (32 ppt) ranged from 29.0° 

to 33.0°c, and the lower lethal 

temperature ranged from 10.4~ to 

14. OOc. The cri tical thermal maximum 

(CTM) of Hawaiian mullet (70 to 125 mn 

SL) is affected both by acclimation 

temperature and by time of day 

(Syl vester 1975). Mean CTM increased 

from 38.5O to 41.3O~ for fish acclimated at 20.0' and 29.0°c, respectively, and mean CTM is about 0.5O~ 

higher at midday than in morning or 

evening. Critical thermal maxima and 

minima were not available for adult 

mullet. 

Sal i ni ty 

Adult mullet have been reported 

from waters with a salinity ranging 

from 0 ppt (Collins 1981) to 75 ppt 

(Simmons 1957). Using fish induced to 

spawn in the laboratory, Sylvester et 

a1 . (1975) found that egg survival was 

highest at a salinity of 32 ppt (the 

hi ghest sal i ni ty tested), whereas the 

greatest survival of larvae was at 26 

ppt in tests from 24 to 36 ppt. When 

juvenile mullet are 40-70 mn SL they 

reach a definitive state of osmoregu1 atory capabi 1 i ty and can to1 erate 

salinities from freshwater to full 

seawater (Nordl ie et a1 . 1982). 

Di ssol ved Oxygen 

Mu1 let 1 arvae apparently cannot 

survive in dissolved oxygen (DO) concentrations below 4 ppm (Sylvester et 

al. 1975). Over a range of 1.0 to 8.0 

ppm DO, eggs incubated in the laboratory for 48 h had a survival rate 

of 0%-3% at concentrations 4.5 ppm and 

below, and 851-901 for 5.0 ppm and 

above. Larvae were held from one to 

four days in concentrations of 4.0-7.9 

ppm DO, and those held for 4 days 

had a mean survival of 0-8s at 4.0-5.4 

ppm, 21% at 6.4 ppm, and 84% at 7.9 

ppm. Although 7.9 ppm in this instance is 146% saturation, there was 

no evidence of gas bubble disease. No 

specific data on oxygen requi rements 

were found for adult mullet, but pre1 iminary experiments with caged fish 

show that they survive at an oxygen 

concentration of 4.4 ppm DO at 29'~ 

and a salinity of 28 ppt (M. R. 

Collins, Univ. of Fla., Gainesville; 

unpublished data). In a study of 

schools of migrating mullet, DO was 

29% lower at the trailing than the 

1 eadi ng edges, suggesting that the 

continual breaking up and reforming of 

the school and changing of position 

within the school a1 low fish at the 

center and trailing edge access to 

water higher in DO (McFarland and Moss 

1967). 

Mullet live in a wide range of 

habi tats and depths and spawn primari - 

ly in relatively deep cool coastal 

waters. The larvae move inshore to 

shallow waters along beaches and in 

salt marshes. In Hawaii, schools of 

mullet less than 50 mn SL were always 

found in waters of minimal depth, 

including the swash zone and tide 

pool s, despite near-lethal temperatures (Major 1978). Juveniles greater 

than 50 mn SL prefer slightly deeper 

waters beyond the swash zone, but 

during flood tides they may move into 

shallow waters vacated by smaller 

mullet. The preference of fish less 

than 50 mn SL for extremely shallow 

water apparently permits them to escape most predators and to feed without serious competition (Major 1978). 
LITERATURE CITED 

Anderson, W. W. 1958. Larval development, growth, and spawning of 

striped mullet (Mu il cephalus) 

along the south At + antic coast of 

the United States. U.S. Fish 

Wildl. Serv. Fish. Bull. 58:501- 

519. 

~rnoid, E. L., and J. R. Thompson. 

1958. Offshore spawning of the 

striped mullet Mu il ce halus in 

the Gulf of &o%peia 

1958; 130-132. 

Bishop, J. May and J. V. Miglarese. 

1978. Carnivorous feeding in 

adult striped mu1 1 et . Copei a 

1978:705-707. 

Breder. C. M.. Jr. 1940. The spawning of ~ugil + ce halus on the ~l orida west coast o~eia 1940:138- 

Breuer, J. P. 1957. Ecological survey of Baffin and Alazan Bays, 

Texas. Publ. Inst. Mar. Sci. 

Univ. Tex. 4:135-155. 

Broadhead, G. C. 1953. Investigations of the black mu1 let, Mu il 

t lorida. Fla. 

cephalus L., in nort I+ west 

Board Conserv. 

Tech. Ser. No. 7. 33 pp. 

Broadhead, G. C. 1958. Growth of the 

black mullet, (Mu il cephalus L.) 

in west and nort west kl ori da. 

Fla. 

+i 

Board Conserv. Tech. Ser. 

No. 25. 29 pp. 

Broadhead, G. C., and H. P. Mefford. 

1956. The mi gration and expl oi tation of the black mullet, Mugil 

k ce halus L. in Florida, as deterrom tagging during 1949- 

1953. Fla. Board Conserv. 

Tech. Ser. No. 18. 31 pp. 

Cato, J. C., P. B. Youngberg, and R. 

Raulerson. 1976. Production, 

prices, and marketing: an economic analysis of the Florida mullet 

fishery. Pages 10-62 in J. C. 

Cato and W. E. McMullo~h, eds. 

Economics, biology, and food 

techno1 ogy of mullet. Fla. 

Sea Grant Program Rep. No. 15. 

Collins, M. R. 1981. 'The feeding 

periodicity of striped mu1 let, 

Mugil cephalus L., in two Florida 

habitats. J. Fish Biol. 19:307- 

315. 

De Silva, S. S. 1980. Biology of 

juvenile grey mullet: a short 

review. Aquaculture 19:21-36. 

De Silva, S. S., and M. J. S. 

Wijeyaratne. 1977. Studies on 

the biology of young grey mullet, 

Mu il ce halus L. 11. Food and 

&hng*cul ture 12: 157-167. 

De Sylva, D. P., H. B. Stearns, and D. 

C. Tabb. 1956. Populations of 

the black mullet (Mu il ce halus 

L.) in Florida. &+kia 

Conserv. Tech. Ser. No. 19. 45 

PP* 

Gunter, G. 1945. Studies on marine 

fishes of Texas. Publ. Inst. Mar. 

Sci. Univ. Tex. 1:l-190. 

Harrington, R. W., and E. S. Harrington. 1961. Food selection among 
f i shes invading a hi gh subtropical 

salt marsh: from onset of flooding through the progress of a 

mosqui to brood. Ecol ogy 42:646- 

666. 

Hoese, H. D., and R. H. Moore. 

1977. Fishes of the Gulf of 

Mexico-Texas, Louisiana, and adjacent waters. Texas A&M 

University Press, College 

Station. 327 pp. 

Kilby, J. D. 1949. A preliminary 

report on the young stri~ed mullet 

~ugi 1 cephal us L: in ' two gulf 

coastal areas of Florida. 0. J. 

Fla. Acad. Sci. 11:7-23. 

Major, P. F. 1978. Aspects of estuarine intertidal ecology of juvenile stri~ed mullet. Muail ce~halus, in ~awaii. U:S.N~~~F#&K 

FiSh. Serv. Fish. Bull. 76:299- 

313. 

McFarland, W. N., and S. A. Moss. 

1967. Internal behavior in fish 

school s. Science 156:260-262. 

Nash, C. E., C. M. Kuo, and S. C. 

McConnel . 1974. Operational 

Overstreet, R. M. 1978. Marine maladies? Worms, germs, and other 

symbionts from the northern Gulf 

of Mexico. Miss.-Ala. Sea Grant 

Consort. Publ . MASGP-78-021. 140 

PP. 

Paperna, I. 1975. Parasites and 

diseases of the grey mullet 

(Mugi 1 idae) with special reference 

to the seas of the Near East. 

Aquaculture 5: 65-80. 

Paperna, I., and R. M. Overstreet. 

1981. Parasites and diseases of 

mullets (Mugil idae). Pages 411- 

493 in 0. H. Oren, ed. Aquacultureof grey mu1 1 ets. Internati onal Biological Program 26. 

Cambridge University Press, 

Cambridge, England. 

Perera, P. A. B., and S. S. De 

Silva. 1978. Studies on the 

biology of young grey mullet 

(Mu il ce halus) digestion. Mar. 

B+~&T=JB). 

Peterson, C. H. 1976. Cruising speed 

during migration of the striped 

mullet Mugil cephalus: an evoluti onary response-To predation. 

Evolution 30: 393-396. 

procedures for rearing .larvae of 

the grey mullet (Mu il cephalus Rivas, L. R. 1980. Synopsis of know- 

. Aquaculture 3:&. 1 edge on the taxonomy, biology, 

distribution. and fisherv of the 

Nordlie, F. G., W. A. Szelistowski, 

and W. C. Nordlie. 1982. Ontopenesi s of osmotic resul ation in 

the striped mu1 let Mu -il ce halus 

L. J. Fish. Biol. '2&bE-- 

Odum, W. E. 1968. Mu1 let grazing on 

a di nofl age1 1 ate bloom. Chesapeake Sci. 9:202-204. 

Odum, W. E. 1970. Utilization of the 

di rect grazing and plant detritus 

food chains by the stri~ed mu1 let 

A. Mu il ce ha1 u; Pages 222-240 in 78Z'E- ed. Marine fox 

chains. 01i;er and Boyd, Ltd., 

Edinburgh, Scot1 and. 

Gulf of ~exico mu1 1 ets " (Pisces: 

Mugil idae). Pages 34-53 - in M. 

Flandorfer and L. Skupien, eds. 

Proceedings of a workshop for 

potential fishery resources of the 

northern Gulf of Mexico. Miss.- 

Ala. Sea Grant Consort. Publ. 

MASGP-80-012. 

Shehadeh, Z. H., C. M. Kuo, and K. K. 

Mil i sen. 1973. Induced spawning 

of grey mullet Mu il ce halus L. 

with fractionate a+- sa mon - pituitary 

extract. J . Fish Biol . 5:471-478. 

Shireman, J. V. 1975. Gonadal development of striped mu1 let (Mugil 
h ce halus) in fresh water. Prog. 

u t. 37~205-208. 

Simnons, E. G. 1957. Ecological 

survey of the upper Laguna Madre 

of Texas. Publ. Inst. Mar. Sci. 

Univ. Tex. 4:156-200. 

Sylvester, J. R. 1975. Critical 

thermal maxima of three species of 

Hawaiian estuarine fish: a comparative study. J. Fish Biol. 

7:257-262. 

Sylvester, J. R., C. E. Nash, and C. 

E. Emberson. 1974. Preliminary 

study of temperature to1 erance in 

juvenile Hawaiian mullet (Mu il 

Prog. Fish- d- u t 

Sylvester, J. R., C. E. Nash, and C. 

R. Emberson. 1975. Salinity and 

oxygen tolerances of eggs and 

1 arvae of Hawaiian striped mu1 1 et, 

Mu il cephalus L. J. Fish Biol . h-629. 

Thomson, J. M. 1955. The movements 

and migrations of mu1 let (Mugil 

cephal us L. ). Aust. J. Mar. 

Freshwater Res. 6:328-347. 

Thomson, J. M. 1963. Synopsis of 

biological data on the grey mu1 let 

Mugi 1 cephal us ~innaeus 1758. 

Aust. 'm.0. Div. Fish 

Oceanogr. Fish. Synop. 1. 66 pp. 
Florida)--Stri ped Mu1 1 et 

7. Aufhor(s) I 8. Perlonn8ng Oqanlratlon Rapt. NO. 

SO271 -101 

Clark R. Collins 

Florida Cooperative Fish and Wild1 ife Research Unit 

11 7 Newins-Zeigler Hal 1 11. ~ontrmct(~) or trant(~) no. 

REPORT DOCUMENTATION '.-REPOUT No, ' 2. 

PAGE i Biol. Rep. 82(11.34)* 

University of Florida 

Gainesville, FL 32611 

3. Racbonent's Accession NO. 

12. Spnsoring Orgeniratlon Name and Address 

National Coastal Ecosystems Team U.S. Army Corps of Engineer 

Fish and Wildlife Service Waterways Experiment Sta. 

U.S. Dep. of the Interior P.O. Box 631 

Washington, DC 20240 

15. Supplementay Holes 

4. Title and Subtntle I Recar( Date 

Species Profiles: Life Hi stories and Environmental April 1985 

Requirements of Coastal Fishes and Invertebrates (South 

*U.S. Army Corps of Engineers Report No. TR EL-82-4 

16. Abstract (Urnit 200 words) 

Species profiles are literature summaries of the taxonomy, morpholo~y, distribution, life history, biological and physical environments, and environmental requirements of coastal species of fishes and aquatic invertebrates. 

They are designed to assist in environmental impact assessment and permit 

review. The striped mullet (Mugil ce halus) is a valuable food fish and 

baitfish. About 31 million pounds Pr were anded in Florida in 1981. Strioed 

~ullet are caught with hook and line, trammel nets, gill nets, and seines, 

and by snagging. Some striped mullet spawn along beaches, butthey usually 

spawn offshore in relatively deep (to 1,800 m) cool waters. Juveniles spend 

their first year in salt marshes, estuaries, and coastal waters. Striped 

mullet usually avoid water colder than 16O C. 

17. Document Analysis a. Dauriploo 

Fishes 

Estuaries 

Feeding 

Growth 

1 b. Identlhsn/Qpen.Endcd Terms 

Striped mu1 let Life history 

Mugil cephalus Spawning 

Sal ini ty requirements Habitat requirements 

Temperature requi rements 

c. COSATl F$eld/Cmup - 

, 19. Stcursty Class (Thcs Ream) 21. No of Pages 

Unl i m i t e d : -- Unclassified- 

' 20. Sccurnt Class (This Page) 

( ~ncl'assified 

(Sea ANS1-239.18) OPTIONAL FORM 272 (4-77) 

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