ML18127A446

Response to 10/16/1973 Letter, Forwards Data on Florida Black Mullet Including Migration Patterns and Thermal Response

ML18127A446
Person / Time
Site:	Saint Lucie
Issue date:	05/07/2018
From:	Robert E. Uhrig Florida Power & Light Co
To:	Regan W US Atomic Energy Commission (AEC)
References
Download: ML18127A446 (11)

Text

4 ~ I FLOIIIDA POWER 5 LIGHl" COMPANV Nr. Hilliam H< Rogan> Jr. Chief, Environnontal Pro)octo Branch 9 4 Directorate of Licensing Office of Regulation U. 8< Atomic Energy Qoamission Washington, D. C, 20545 Dear Nr>> Regans res st. Lucio Unit Mo. 2 Environmental Roport Docket 50-389 Vo comploto the z'osponoes rocxuircd by your October 16, 1973 letter wo aro enclosing copies of tho references roguootod by cpmstion 18 parts c and d.

The data on the Florida Black Mullet includes migration'atterns and thermal response>> Data on the turtle hatchling'uccess is not yot complete ahd will be forwarded aa soon as tho Dopartmont of Natural Rooources repoxt is availablo. Tho raw data to date, howevers agrees favorably to that for 1971 and 1972 which produced a 600 success rato.

Questions 18 a and b wore previously answered by oux letter of October 1, 1973>

3 Yours vexy truly, Robert E. Uhrlg Director of Nuclear Affairs REU~nch Enclosure cci Hr< Jack R< Newman Wx. Richard Widrig Battolle northwest Labs Richland, lfashington 99352 COPY SENT REGION HELPING 8 UILO FLORIDA

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LISA--THE FLORIDA BLACK N~)LET Charles R. Futch 1 Salt Water Fisheries Leaflet 6 May 1966

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'fter I~in il halus ~ce Linnaeus Carson (1944)

Figure 1 Florida produces 7'er cent of the mullet caught in the U. S. Since 1960, approximately 35 million pounds of mullet have been landed in Florida each year with an annual value to fishermen of about 1.9 million dollars. Ninety per cent of this production comes from Florida's west coast with Lee County (Ft. AMyers area) leading in commercial landings. Although black or striped mullet, ~gu

~ce balue Linnaeus, dominates the mullet catch, four other species of mullet il com-prise an incidentaf minority.

For decades, the traditional market for mullet has been the Southeast and some northern cities where fresh whole finfish were especially popular. However, widespread acceptance of deboned and frozen fillets, fishsticks and steaks by supermarket chains and American housewives has cut heavily into the market for fresh fish.

Baked, broiled, smoked or deep fat fried mullet is delicious and provides superior animal protein, minerals, vitamins and polyunsaturated fats. Because mullet is abundant and moderately priced, institutional dietician.

it is a bargain for the housewife and Lisa is the Spanish name for black mullet and the name for processed mullet as established by Florida's seafood industry and trade the Florida Board of Conservation. Before the introduction of the name Lisa~ an extensive m rketing survey by the University of Miami indicated that the flavor and appearance of canned mullet would allow it to compete with other types of canned fish. Lisa may be substituted in many recipes calling for tuna, salmon or even crab meat.

Tasty recipes for Lisa and fresh mullet are available from the Florida Board of Conservation.

To increase the demand for fishery products, the Florida Board of Conservation has published a pamphlet, How to roduce and sell smoked Florida Fish, (Educational Series No. 8) primarily for the benefit of wholesalers and retailers. This pub-lication is available upon request. Details are given for building a smokehouse capable of producing up to 2,000 pounds per week.

Mullet is widely used as bait by commercial and sport fishermen. Smaller mullet are sometimes used as live bait while larger ones are stripped for cut bait.

This public document was promulgated at an annual cost of S48.30, or I s s

.S.12,perdcopy to make research results and.marine resources informa-

',aon avaitabte"to scientists enrf the, public.. Thisuis+ second, printing.

n DISTRIBUTION s

Black or striped mullet, is one of the most widely distributed food fishes in the world. It. is found in coastal waters and estuaries throughout the tropics and sub-tropics (Figure 2).

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Distribution of black mullet.

After Thomson (1963)

Figure 2 SIMILAR SPECIES Four other mullets occur in Florida:

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The silver mullet, ~Hu il curema Valenciennes, in the Florida Keys. These mullets are also used by commercial and sport fishermen as live bait. A provisional hey to the genus ~tfu il from the eastern United States by Dr.

Victor G. Springer is presented on Page 5.

LIFE HISTORY In Florida, black mullet spawn from October through February, but chiefly from November through January, Before spawning, mullet form large schools and migrate from their typical estuarine habitat into offshore waters. Some individuals remain in inshore areas and apparently do not spawn during that year. There are indications that mullet usually spawn from 5 to 20 miles offshore in the Gulf of Mexico.

Spawning has also been observed as far as 40 to 50 miles southeast of the Mississippi River Delta. In Florida, spawning migrations are southward along the entire east coast and from Cedar Keys to Homosassa on the west coast. However, migrations from Tampa Bay are usually northward. No distinct coastal migration patterns have been found in other regions of Florida. Indications of a return migration after spawning

"-'Cc..sidered by some, to be synonymous with M. curema.

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'~dontiadicts an old theory held by some fishermen that mullet do not return after s'pawning and are consequently lost to the fishery.

Adult females produce from 1.2 to 2.7 million eggs in a single spawning. Eggs are shed into the water and are fertilized by accompanying males. Hatching of the eggs occurs approximately 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after fertilization. Upon hatching, larval mullet Larvae into postlarvae -'n about are about two and one-half mm (O.l inch) long. grow a week. During this growth they migrate inshore and, at a length of 20 to 30 mm (one inch), enter grassy areas of sequestered brackish water bays. These growing mullet find ample nourishment and protection from predators in grassy nursery areas.

Snook, redfish, speckled trout, tarpon, shrimp, blue crabs and other marine animals of commercial and sport fishery importance also spend part of their sub-adult lives in such inshore nursery areas. In many parts of Florida, indiscriminate dredge val- and fill projects and sewage and industrial pollution have destroyed many acres of uable nursery grounds. To insure survival of mullet. as well as many other animals.

it is imperative that existing grass beds be protected from further destruction.

Young black mullet reach 50 mm (two inches) in length within five months and are then considered juveniles. They usually attain a length of 185 mm (four and one-half inches) by the end of one year and begin to enter the commercial catch in their second year at a length of about 265 mm (ten and one-half inches). For a more comprehensive description of the larval stages oi ti. ~ce halus, the reader is referred to Anderson (1958). It should be mentioned that mullet under ten inches are protected by law in most areas of Florida.

There is a rough correlation between size and age at maturity and average sea temperature. Mullet from areas of warmer waters mature earlier than mullet from areas of colder waters. In Florida, black mullet mature in one to two years at a length of from 230 to 350 mm (9 to 14 inches). In the Black Sea, where average sea temperature is lower than that of Florida, mullet mature in six to eight years at a length of from 310 to 370 mm (12 to 15 inches).

Water temperature affects growth rates. Mullet in warmer climates grow faster than those in cooler regions. Mullet also grow faster in spring and summer than in autumn and winter ~

Adult mullet are found in many habitats, and are often seen far upstream in fresh water rivers. Mullet have also been reported from Laguna Hadre in Texas in water with a salinity twice that of normal sea water.

POOD AND 'FEEDING 1n particular localities. food items may differ. Microscopic detritus, crus-taceans and plankton constitute the bulk of the diet. Mullet feed on. shallow banks of bays and estuaries during flood tide. When the tide begins to ebb, they cease feeding and form schools.

FISHING METHODS Because mullet are schooling fish and also have a remarkable (and unexplained) practice of jumping, they are easily spotted by fishermen. In Florida, where most mullet fishing is done at night fishermen can hear a school splashing and so deter-7 mine when and where to set their nets.

sh Siebenaler (1955) described several types of fishing gear used in Florida.

(1) GILL NET:

o This net is made of 3 to 4 1/2 inch stretched mesh. Net depth varies with depth of waters fished. The nets, which are 200 to 400 yards long, are stacked in the bottom of a rowing skiff towed by a larger powered vessel. When a likely fishing spot is reached, the fisherman anchors the power launch and begins rowing the skiff and setting the nets. Nets are set in a variety of ways, but always in some pattern which encircles the school. Fish are then frightened into the net where they become entangled (Figure 3). After a short time the net is picked up and.

the catch removed.

(2) TRAMMEL NET: "A trammel net is made by hanging three walls of webbing to a 'single cork and lead line. The outer walls of netting are made of 8'6 to >215 cotton twine, with a stretched mesh of from 8 to 12 inches. The inner wall of webbing is made of smaller stretched mesh (two to four inches) depending upon the species and size of fish sought. Fish are captured by passing between ~the large meshes of the outer wall, then pushing the small mesh inner wall into a pocket between the large meshes on the wall on the opposite side of the net." (Figure 4) Trammel nets are usually set in the same manner as gill nets.

(3) BEACH SEINES: A'mall beach seine about 100 yards long is frequently used on Florida's east coast. It is very often a gill net. One end is secured on shore end the fisherman carries the other end into the water walking up-current. When the desired seine area is covered, the end of the net is quickly carried back to shore.

The catch is then beached.

Another popular beach seine is the "Apalachicola Seine." This seine (1200 to 1800 yards long) is set from a power launch, and a crew of nine to twelve men is necessary to set the net and beach the catch.

(4) CAST NET: Cast nets are used commercially and non-commercially in Florida.

"Cast nets are hand-knitted and discoid in shape with a weighted circumference t..at sinks to the bottom when it is thrown. The lead line is closed by drawing in the

'tuck'ines (brailes) passing through the apex of the net."

POND CULTURE OF BLACK MJLLET Unusually high, but somewhat questionable, production figures of mullet from brackish water ponds in several Asiatic countries have stimulated great interest in similar ventures in the United States. Black mullet has been highly recommended by fishery workers because:

(1) It is one of the major species reared in the Orient.

(2) A brackish water pond closely approx.'mates the natural habitat of these fishes.

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w5 Although biologic reasons for choosing mullet f a pond culture fish are sound, economic factors must be considered. American producers must provide fish that command a high market price. Mullet are so abundant that prices are low. The high cost of pond maintenance would be prohibitive.

Presently, pond culture of mullet does not appear to be economically feasible.

However, an increase in the demand for mullet arising from new fishery products, such as Lisa, smoked mullet. mullet fishsticks and frozen fillets~ might raise the value of the fishery to a level at which pond culture could become a profitable venture.

The Florida Board of Conservation has been instrumental in supporting and con-ducting research on the Florida mullets. This research is the basis of our under-standing of the biology of these species, and from this understanding will arise sound management of the resource. In addition to basic research, the Florida Board of Conservation has been working on means to increase the demand for this product, thereby providing the Florida mullet fisherman with a broader, more stable market and higher prices. The new Lisa canning plant in Miami is a direct result of some of these efforts.

The Marine Laboratory is also conducting a study on the utilization of the mullet offal remains fro.i ."he Miami plant as fish meal or fertilizer. If this process can be developed it will help maintain the economic stability of

'other similar fish canning plants in Florida.

this and A PROVISIONAL KEY TO THE FIBHES OF THE GENUS ~fUGIL FROb~f THE EASTERN .UNITED STATES (Extracted, for the most part, from the literaturh), Dr. Victor G, Springer.

lA. Second dorsal and anal fins almost entirely scaleless. The anterior rays and perhaps the most proximal portions of th>> bases of these fins with a few seal s.

Adults with dark longitudinal stripes. Anal elements usually III,8 (th: young will have II,9; tho third clement becomes spinous with growth). . . . . . . .2 2A. Scales 31-35, usually 32-34, in a longitudinal series from the upp.r angle of the opercle to th caudal base...~>lu il liza Valenc'ennea 2B. Scales '8-42, usually 39-41, in a

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longitudinal series from the upp~ r angle of the opercle to the caudal base. . .~Nu il halus binnaeus

~ce 1B. Second dorsal and anal fins almost entirely covered with small scales even in young.

Sides without longitudinal dark stripes. Anal elements usually III,8 or III,9 depending on species (the young'will have one spine less and one ray more; the third

.anal element becomes spinous with growth). . . . . . . . . . . . . . . . . .3 3A. Anal elements usually III,8. Scales 31-33, usually 32, in a longitudinal series from the upper angle of the opercle to the caudal base. . .ltuzil trichodon (Posy) 3B. Anal elements usually III,9. Scales 35-39, usually 36-38, in a longitudinal series from the upper angle of the opercle to the caudal base. . . . .4 4A. Scales 35-37, usually 36 in a longitudinal series from the upper angle of the opercle to caudal base. Origin of anterior dorsal fin nearer

• o" 4B. Scales 37-39, usually 38, 'in a longitudinal series from upper angle of the opercle to caudal base. Origin of anterior dorsal fin about mid-way between tip of snout and middle of caudal base, or nearer caudal base. . . ... . . . . .Mugil curema Valenciennes

.!',mgonsidtu'od'synonymous+with H. curema-

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v PERTINENT LITERATURE

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e ~ s ANDERSON, W. W.

1958 Larval development, growth and spawning of striped mullet (M~u~il ~ce balue) along the South Atlantic coast of the United States. U.S. Fish and Wildl: Serv., Fish. Bull.

58(144): . 501-519.

v ARNGLD5 E ~ L~ AND Je Re THRiPSON 1958 Offshore spawning of the striped mullet ~Mu Gulf of Mexico. ~Co eia 1958 (2): 130-132.

il ~ce balue in the BRAWNER~ J. AND P. A'BKQfS 1956 How to produce and sell smoked Florida fish. Fla. Bd. Conserv.,

Ed. Ser. 8: 1-9.

BROADHEAD' e C~

1953 Investigations of the black mullet, M~uil ~ce balue Le in 5 northwest Florida. Fla. Bd. Conserv., Tech. Ser. 7: 1-34.

BROADHEAD~ G. C.

1956 Growth of the black mullet ()~(u il ~ce balue L.) in west and northwest Florida. Fla. Bd. Conserv., Tech. Ser. 25: 1-29.

BROADHEADy G ~ C ~ AND He P MEFFORD 1956

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The migration and exploitation of the black mullet halus L. in Florida, as determined from tagging during

~Mu il

~ce 1949-1953. Fla. Bd. Conserv.5 Tech:. Ser. 18: 1-30.

CARSON, R. L. a 1944 Fish and shellfish of the South Atlantic and Gulf coasts.

U.S. Fish and Wildl. Serv.~ Conserv. Bull. 37: 1-45.

IDYLL, CLARENCE P. and J. W. SUTTON 1952 Results of the first year's tagging of mullet, M~uil

~ce halus L., on the west coast of Florida. Trans. Amer.

Fish. Soc., 81: 69-77.

JOHNS DAN~ M. C.

1954 Preliminary experiments in fish culture in brackish water ponds. Pro . Fish. Cult. 16(3): 131-133.

SIEBENALERp Je Be 1955 Commercial fishing gear and methods in Florida. Fla. Bd.

Conserv. Tech. Ser. 13: 1-45.

SPRINGER'. G.

A provisional key to the fishes of the genus Muail from the eastern United States. (Extracted for the most part from the literature). Typewritten copy, 2 pp.

SPRINGER, V. G. and K. D. WOODBURN 1960 ~

An ecologica study of the fishes of the Tampa Bay area.

Fla. Bd. Conserv. Prof. Papers Ser. 1: 1-104."

TH(MSON, J. M.

1963 Synopsis of biological data on the grey mullet, >~fu halus Linnaeus 1758. Div. of Fish. and Ocean. Common.

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~ce Sci. and Ind. Res. Or ., Fish. Synop. No. 1: 80 pp.

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". OIaflllL Lotiafc"tery Q. F&r."bur~ Pi" 1~a

'-;.Thc'patterri is scattered, with fish moving iri both'irections from ..

the point of rclcasc.

~ f:ENSACOLA TO PANAMA CtTY,... '. "-, -" ~

19'*9. 1950, 1951, and 1952, 1,185 ta"ged."mullet were 'uring in this area. Of thc 31S recoverics with migrational data, 17, or rc-"'cascd

'5.3 per cent. werc r<<covcrcd further than 20 miles from thc point of re-lease. Tlirce muilet tagged at Pensacola were rccovercd near Mobile. Ala-bama. No active caiiipai~ to recover fish was conducted outside of Florida nor ii~ any tagging conducted in tlie Alabama section of thc c'oast to check migrations in thc other direction. From Panama City, rnuH<<t moved to t)ic east and were recovered at St. Marks. The migra-

tional patterns of tlicsc Qsh arc shown in Figure 10.

i '~-~ALABAMA t FLORIOA J 1 NICEVILLE PANAMA CITY ST. MARKS PENSACOLA PORT ST. JOE

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".,-'Ficvnr. 10. hiigzntional patt<<ms of lish rclcascd in the Panama City, Niccvillc, and Pensacola areas doring 19 t9-'1952.

'.,~ GENERAL MOVEMENTS yt Figure ll shows the gcncral movements of thc tagged mullet along

<.,-.both coasts of Florida, to ~ether with thc Gulf of Xlczico and Florida east f..-.."coast water current patterns as shown by 'ipper (1954).

.'" (L The many sliort migrations have been omitted in this figurc for

,'.; r simplicity.

A major movement of mullet was noted along tlie Florida cast coast I. "during the pre-spawning period. About 2o5" pcr cent of thc Iiavport tag

'".,recovcrics showed inullet movcmcnts furt)icr tliari 20 inilcs from the point I:,.;of release, and many of thc ihiayport lish followed thc gcncral pattern

';..:illustrated. This migration was noted in three succcssivc years and ap-

, .'.pears to bc an annual occurrcncc. Some fisli from tlie Titusville taggings I';".also followed this sIIuthward route, but thcsc fish represented less than r" .5 pcr cent of recovered lish tagged at Titusvil)c.

N ~,v, The other possible pattern of movcmcnt of fLsh was noted as being I.-".;south from EIomosassa and Cedar Keys. Althoiigh I<<ss than 10 p<<r cent

<-',~'of the recoveries for tlicse taggings p;irticipatcd in tliis movcmcnt, it was j~.-'noted in 1952 and again in 1953.

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'ith these csccptions thc movements of mullet along the coast of 21

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- '.. 'florida appear to bc random in fashion,'Eith less than 10 pcr cent

,P> '. the fish moving further than o0 miles &am their point of relcas

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.';., ", tp~ of movcmcnt occurs a!1 along thc coast and tlicrc is no indic E.'i(i(E isolated populations of black muHct along cithcr of th( I pq,} "'aistinctly

1incs. Some tag r~~'cries point to extensive migrations of fish fri iii ii,

'alt and brncGsh water areas into thc frcs!i ivatcr rivers, but th( }aej

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of a commercial iishcrv for muL'ct in fresh ~vater preveiits many of t},,c

-fish from being recaptured there. Since large aggregations of fish a,c known to inhabit the fresh water lakes and rivers of the state in certa'z period of thc year, and since all thc evidence, both in Florida and f, other areas, points to salt or brackisli water spaiiming, it seems reaso(iagj.

'o suppose that these migrations take place before the fall spanaiin~

pcrioa each year. Yo estimate of t}ic numbers of fish present in tlic fres}'E xvatcr areas is possible, nor does thcrc sccm to bc any xvav of obtainia ~ (nia}i tlus Ggure.

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h Etc(rnz 11. Yhc hvo distinct migrational paths of Florida b}aek mullet as lj

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'- 2R t}ic tagging pro@run. Currinit patterns }Eave been taken from Lcippcr, l95i ind'y

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