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By MATTHEW R. PALMTAG AND G.J.HOLT

Fire shrimp (Lysmata debelius) are a popular spe-cies in the marine aquarium trade. Wild collection ofmarine ornamental fishes and invertebrates, such as thefire shrimp, contribute to the pressures on natural popu-lations of coral reef animals. The development of cap-tive culture techniques would help safeguard coral reefsand is essential for the expansion of marine ornamentalaquaculture technology. This paper presents a completeand descriptive protocol for the captive culture of fireshrimp. Larvae were fed rotifers (Brachionus plicatilis)and brine shrimp nauplii (Artemia sp.) both enrichedwith algae (Nannochloris oculata) for the first 12 days.From day 12 post hatch to metamorphosis, larvae re-ceived 0.5 g of frozen, pureed shrimp and squid in addi-tion to brine shrimp nauplii enriched with algae. Weraised 168 shrimp that metamorphosed into juveniles be- Fig. 1. Adult fire shrimp (Lysmata debelius)tween 75 and 158 days post hatching. All shrimp thatmetamorphosed into juveniles provided healthy individuals suit-able for the marine aquarium trade. shrimp that metamorphosed into juveniles between 75 and 158days post hatching. All shrimp that metamorphosed into juve-

niles were healthy and suitable for the marine aquarium trade.Techniques described in this paper lay the ground work for fu-ture research and development on the production of fIfe shrimp,possibly contributing to the preservation of marine ornamentalorganisms and coral reefs.

Reproductive BiologyUnlike the majority of decapod crustaceans, fire shrimp are

simultarieous hermaphrodites (Fletcher et al. 1995), meaning anindividual can simultaneously function as a male and female.Similar findings were reported for a closely related species, thepeppermint shrimp (Bauer and Holt 1998).

Broodstock Tank

Broodstock are kept in 76- to l14-L (20- to 30-gallon) aquari-ums with standard undergravel filtration, shell hash substrate,and small rocks arranged to imitate natural reef habitat. Mated'pairs become territorial and need to be separated from other fireshrimp to prevent aggression that may result in maiming or death.In our experience, aggression between the individuals of a matedpair does not occur, however, aggression is common when threeor more fire shrimp are together. Physical parameters for thesuccessful breeding of fIre shrimp are as follows: temperature25 to 28C (77 to 82F), salinity 33 to 37 ppt, photoperiod 12hr light: 12 hr dark, and pH 8.0 to 8.2. Under these conditions,fire shrimp in our laboratory have produced 500 to 3,500 eggsevery 10 to 20 days.

IntroductionOrnamental fish and invertebrate collections on coral reefs

contribute to coral reef habitat destruction and degradation ofwild populations. Cyanide fishing for food fish and ornamentalsis reported to damage coral reefs, and is practiced in at least 15countries (McManus et al 1997;UNEP/IUCN 1988). Captivecultivation of marine ornamental organisms is a possible "envi-ronmentally friendly" solution to supplying the growingaquarium hobby with coral reef organisms. While many fishesand invertebrates sold in the freshwater aquarium industry arecultured in captivity, more complex requirements of marine or-namental organisms have impeded the development of marineornamental aquaculture technology. Development of this tech-nology requires advancements in captive rearing protocols. Wedeveloped a protocol for the captive rearing of fIre shrimp (Fig-ure 1) because information is limited, it is a popular organism inthe aquarium hobby, and it demands a substantial price, whichcould benefit the growth of marine ornamental aquaculture tech-nology.

Fletcher et at. (1995) published the only information pertain-ing to the captive rearing of this species. They provided infor-mation about rearing the fire shrimp in captivity, however theydid not provide a detailed protocol. The purpose of this work isto provide the details of a protocol we used for rearing fIre shrimpin captivity. The methods used in this paper are an enhancementof culture techniques used to rear peppermint shrimp (Lysmatawurdemanni, Riley 1994). With this protocol we raised 168

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Fig. 2. Adult fire shrimp carrying eggs

Relocation of BroodstockSpawning of fife shrimp can be

achieved in the brood stock tank,however air stones, under gravel fil-tration, and changing tank environ-ments often result in high larval mor-tality. For successful captive cultiva-tion, brooding fife shrimp should beremoved from the tank and placed ina hatching/rearing chamber in a lar-val rearing system (described later)9 tol9 days after eggs appear on theswimmerets. Our protocol is to movethe brooding fire shrimp into the lar-val rearing system as close to hatch-ing time as possible, and return theshrimp to the broodstock tank imme-diately following larval release. Fer-tilization of new eggs occurs aftermolting which can take place 0 to 24hours after larval release.

Recognizing the eggs on the fifstday of adhesion to the swimmeretsis extremely difficult because of boldpigmentation throughout the body ofthe adult shrimp. The swimmerets ofa fire shrimp carrying eggs (Figure2) will appear darker than the ab-dominal segments above, in contrastto the lighter color of the swimmeretsof a fife shrimp without eggs. Hoursbefore the eggs are ready to hatch theeyes of the larvae inside the egg canbe observed; this is an indication thatit is time to move the parent.

Care must be taken when relocat-ing brooding shrimp to avoid dam-aging the eggs. Instead of netting theparent fire shrimp, a 500- to 1000-ml (15- to 30-fl. oz) beaker or jar isplaced on the substrate of the tankand the shrimp is chased into it byhand. Once the shrimp is completelyin the beaker, the opening is coveredby hand and slowly raised out of thetank. The beaker is then placed intothe larval hatching chamber withinthe rearing chamber (Figure 3) andthe parent is acclimated over a pe-riod of at least 20 minutes in the bea-ker before it is released into thehatching chamber.

with a 100-L (26-gallon) externalbiofilter (Figure 4). Six 18-L (5-gal-Ion) PVC rearing chambers (Figure5) with 48-um (0.DO2-in.) nitex mesh,are placed in the tank. Dimensionsof rearing chamber are: 25.4 cm (10in.) diameter and 46 cm (18 in.)height. Rearing chambers concen-trate larvae and food, thus increas-ing food encounter rates. Rearingchambers also provide shelter for thelarvae and decrease the possibility ofphysical damage from aeration, wa-ter exchange and heating elements.

The hatching chamber is a plasticcylinder used to contain the parentin the rearing chamber for hatchingand allows removal of the parent,minimizing the chance of acciden-tally capturing and removing larvae.The cylinder (Figure 3) is made ofrigid plastic mesh with 1 x 1 cm (3/8in. x 3/8 in.) holes, 60 cm (24 in.) inlength, and 22 cm (8 3/4 in.) in di-ameter, fits snug into the rearingchamber. A raised level of 1 x 1 cm(3/8 in. x 3/8 in.) rigid plastic mesh,22 cm (8 3/4 in.) in diameter, is fas-tened in with cable ties 15 cm (6 in.)from the surface of the cylinder.

To provide water flow into thehatching and rearing chamber a 15 x3 cm (6 in. x 12 in.) L-shaped I-inchPVC standpipe equipped with a 3 cm(1 in.) air stone is used (Figure 6). Ahole, 3 cm (1 in.) in diameter, is cutinto the hatching chamber 15 cm (6in.) above the raised level to provideaccess for the standpipe. Thestandpipe provides a steady flow ofoxygenated water directly to the par-ent fIfe shrimp, which will aid in therelease of larvae as they hatch off theswimmerets.

A 5cm3 (2in3) rock is placed onthe raised level of the rigid plasticmesh to mimic the parent fire shrimptank living conditions (be sure therock cannot wobble or fall over ontothe broodstock).

Fig. 3. Hatching chamberwithin the rearing chamber

Removal of ParentTo remove the parent fire shrimp

after the eggs have hatched, lift thehatching chamber until the raisedlevel of the rigid plastic cylinder isapproximately 3 cm (1 in.) below the

Larval Rearing SystemThe recirculating larval rearing

system consists of a 400-L (lOS-gal-lon) round fiberglas tank equipped

surface of the water. The parent isagain chased into the beaker by handand both the parent and mesh cylin-der removed. This method minimizesthe possibility of capturing larvaewith the adult.

Airline Rearing Rearing\ Chamber Chamber~ l1~~~~~~tandPiPe Tank Standpipe

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JReturnLine

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. t-;t-FilterI) "'Drain1 )

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Fig. 4. Recirculating larval rearing system

10 in. PVCr- ~

48 urn Nitex Mesh

hatching brine shrimp nauplii, androtifers and brine shrimp nauplii wererinsed prior to release into the larvalrearing chamber, using a 48 !lIn(0.002-in.) nitex mesh sieve). In ad-dition, every day beginning with day1, 200 ml (6.8 fl oz) of algae(Nannochloris oculata) at a concen-tration of -20,000,000 cells per ml(0.034 fl oz), was added to each rear-ing chamber to provide nourishmentfor surviving rotifers and brineshrimp nauplii. On days 6-11 algaeenriched brine shrimp nauplii weremaintained at a concentration of-50,000 per rearing chamber. Deadlarvae, uneaten food and waste wereremoved from each rearing chamberevery other day by use of a vinyl si-phon tube with an inside diameter of6.35 mm (5/32 in.). On day 10, lar-vae in each rearing chamber wereremoved by beaker and transfeuedinto clean rearing chambers. This wasrepeated for all rearing chambersevery 10 days.

On days 12-158, algae enrichedbrine shrimp nauplii were fed at aconcentration of -30,000 per rearingchamber along with 0.5 g (0.0175 oz)of frozen food. Frozen food com-posed of 50 percent squid (Illex spp.)and 50 percent shrimp (Penaeus spp.)was pureed in a blender and refro-zen. Portions of this mixture werethawed each morning and adminis-tered to the surface water of the rear-ing chamber. Beginning on day 14and every fourth day thereafter 4 mls(0.13 fl oz) of Seachem reef calcium(polygluconate calcium) was added.

~Frame46cmor

18 in.

l48 urn Nitex Mesh

Fig. 5. Rearing chamber

Larval DevelopmentFire shrimp pass through at least

10 larval stages before molting to thepostlarval form. Prior to stage 5 thefifth parapodia became flattened andexpanded into long paddle shapedstructures, which may assist in main-taining position and orientation in thewater column (Figure 7). Larvae alsouse these limbs for capturing foodand holding onto solid structures inthe water column (Fletcher 1995).After the final molt to the juvenilestage, the compound eyes are locatedon the head rather than terminally

Larval RearingSuccessfully raising the larvae to

juveniles is still in the experimentalstage. So far about 10 percent sur-vival through the larval stage hasbeen accomplished using the follow-ing techniques.

Physical parameters of the larvalrearing tank are as follows: tempera-ture 25 to 28C (77 to 82F), salin-ity 33 to 37 ppt, photoperiod 12 hrlight: 12 hr dark, and pH 8.0 to 8.2.The larvae were divided equally intosix 18 L (5 gallon) rearing chambers(approximately 250 larvae per cham-ber). Larvae were moved by gradu-ally submerging a 250-ml (8 fl oz)beaker into a mixture of water andlarvae, and transferring the larvae toalternate rearing chambers. As thedensity of larvae was reduced, thevolume of water in the rearing cham-ber was decreased by lifting it up,keeping the water line above the bot-tom of the rearing chamber. This con-centrates the remaining larvae so theycan be collected. Larvae were re-leased by submerging the beaker halfway through the surface of the waterand slowly releasing the water andlarvae. The standpipe was added toeach rearing chamber after the lar-vae were divided. Air pressure of thestandpipe was set to a low level, en-abling larvae to slowly circulatearound the rearing chamber. Slowflow velocity, 100 to 400 ml per min.(3.3-13.3 fl oz per min.), allows thelarvae to grasp the sides of the en-closure; too much current will sweepthem off.

On day 1, each of six rearingchambers were given -50,000 algae(Nannochloris oculata) enriched ro-tifers (Brachionus plicatilis) and-20,000 algae enriched brine shrimpnauplii (Artemia sp.). This concen-tration of rotifers and brine shrimpnauplii was maintained through day5 (Note: cysts were removed after

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Fig. 6. Stand pipe used in the hatching andrearing chamber

placed on stalks, and the paddle-likeappendages becoOle reduced to thetypical adult appendages (Figure 8).At this tiOle the ShriOlp are no longerfree swiInIning but instead settle ontothe bottoOl and sides of the rearingchamber. This benthic transfonnationOlay enhance their ability to prey onlarger, Olore diverse foods and in-creases the aniOlals feeding opportu-nities (Riley 1994).

tend for this information to enablescientists and hobbyists alike to re-fine this technique or develop betterones, expand research, and providean alternative to the capture ofstressed and endangered wild popu-lations.

AcknowledgementsCindy Faulk and Charlotte Kucera

deserve a special thanks for assis-tance in every phase of the study andGreg Dirnijian for photographing thevarious life stages of the fire shrimp.We would also like to express grati-tude to the people and organizationsthat ultimately made this work pos-sible with their financial assistance:Hugh A. McAllister, Jr., CharitableFoundation, The World WildlifeFund, and Texas Sea Grant College

Program.

Fig. 7. Fire shrimp post-larvae (day 68) with ex-panded fifth parapodia

MetamorphosisThere were 400 larvae on day 55,

when they were counted for the fIrsttime. Larvae were not counted ear-lier for fear that handling stress mightincrease mortality. The first meta-morphosis from a larva into a juve-nile occurred on day 75. Previousstudies indicate that the larval cycleof fire shrimp lasts for 11 to 15 weeks(77 to 105 days) (Fletcher et al. L. C.t d1995). Further research on larval nu- Iterature 1 etritional quality may decrease the Bauer, R.T.; and Holt, G.J. (1998).number of days necessary for Simultaneous hermaphroditism in themetamorphasis to the juvenile stage. Fig. 8. Newly transformed juvenile fire shrimp (day marine shrimp Lysmata wurdemanni

By day 158,42 percent of the lar- 83) (Caridea: Hippolytidae): anvae counted on day 55 had metamor- undescribed sexual system in the de-phosed into juveniles, the remainder died. We were .unable to capod Crustacea. Marine Biology, 132: 223-235.look at overall mortality and survival, however we estImate ~at Fletcher, D.J.; Kotter, I., Wunsch, M. and Yasir, I. (1995). Pre-approximately 11 percent of the spawn survi~ed to the j~verule liminary observations on the reproductive biology of orna-stage. Survival during the juvenile stage was hlg.h (appro.Xlma~ly mental cleaner prawns. Int. Zoo. Yb., 34, 73-77.99 percent). Six months from the date of hatchmg, ~e J.uverules Haywood, Martyn; and Wells, Sue. (1989). The manual of ma-ranged from 30 to 40 mm (1.2 to 1.6 in.) long. At thIS tIme they rineinvertebrates. Salamander Books Ltd., Morris Plains, NJ.were suitable for sale to marine ornamental retail stores for a McManus, J.W., Reyes, R. B. Jr., and Nanola, C.L. (1997). Ef-price of $10 each. Even late metamorphosing shrimp provided fects of Some Destructive Fishing Methods on Coral Coverviable product for the marine aquarium trade. and Potential Rate of Recovery. Environmental Management

Vol. 21, No.1, pp. 69-78.Riley, Cecilia M. (1994). Captive spawning and rearing of the

peppermint shrimp (Lysmata Wurdemanni). Sea Scope Vol.11.

Simoes, F.; Yasir I., Jones, D.A. (1998). Reproductive Biologyof Lysmata debelius (Bruce 1983) and L. ambionensis (DeMan 1888), (Crustacea, Caridea) Tropical Marine CleanerShrimps Important In the Sea Water Aquarium Trade. Ab-stract, World Aquaculture Society, Las Vegas, 1998,3 pp.

UNEP/IUCN. 1988. Coral reefs of the world, 3 vols. UNEPRegional Seas Directories and Bibliographies.IUCN, Gland,Switzerland and Cambridge, UK/UNEP, Nairobi, Kenya.

SummaryThe primary objective of this research was to provide a pro-

tocol for the captive cultivation of fire shrimp. Protocols such asthis are essential for the development of marine ornamentalaquaculture technology. This technology may allow aquacultureto provide a form of coral reef habitat preservation and conser-vation in the near future. Using this protocol we were able toraise 168 adult fire shrimp from a single hatch (estimated hatch1,500 larvae, 11 percent success rate). Our results suggest thatfire shrimp are appropriate subjects for future research and de-velopment of marine ornamental aquaculture technology. We in-

A TEXAS SEA GRANT COLLEGE PROGRAM RESEARCH REPORT.The research described in this report was funded in part by Project R/M-61 ofInstitutional Grant NA86RGOO58 to Texas A&M University from the NationalSea Grant Office, National Oceanic and Atmospheric Administration, U.S. De-partment of Commerce. TAMU-02-201. September 2001. 1MTexas