THE WINSTON CHURCHILL MEMORIAL TRUST OF AUSTRALIA. Report by Associate Professor Jamie Seymour 2016 Churchill Fellow

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1 THE WINSTON CHURCHILL MEMORIAL TRUST OF AUSTRALIA Report by Associate Professor Jamie Seymour 2016 Churchill Fellow The Dr Dorothea Sandars and Irene Lee Churchill Fellowship to increase the knowledge of rearing Box and Irukandji jellyfish in captivity I understand that the Churchill Trust may publish this Report, either in hard copy or on the internet or both, and consent to such publication. I indemnify the Churchill Trust against any loss, costs or damages it may suffer arising out of any claim or proceedings made against the Trust in respect of or arising out of the publication of any Report submitted to the Trust and which the Trust places on a website for access over the internet. I also warrant that my Final Report is original and does not infringe the copyright of any person, or contain anything which is, or the incorporation of which into the Final Report is, actionable for defamation, a breach of any privacy law or obligation, breach of confidence, contempt of court, passing off or contravention of any other private right or of any law. Signed Jamie Seymour Dated Friday, 7 December 2018

2 Key Words: Jellyfish, box jellyfish, aquariums, rearing, husbandry, cubozoans, scyphozoans. Contents Key Words: Jellyfish, box jellyfish, aquariums, rearing, husbandry, cubozoans, scyphozoans Introduction:... 4 Executive summary... 5 Program for Associate Professor Jamie Seymour for Churchill Fellowship in Main Body:... 7 Georgia Aquarium... 7 Fig 1: Georgia aquarium, Atlanta... 7 Fig 2: Polyp holding and ephyra collection tanks... 8 Fig 3: Plastic substrate containers for settlement of polyps... 9 Tennessee Aquarium Fig 4: Tennessee Aquarium, Chattanooga Fig 5: Lugol s solution (iodine) Fig 6a: Flow though ephyra collection tank Fig 6b: Flow through tank in-situ with polyp tank Fig 7b: Commercially produced oyster and rotifer slurry for food for jellyfish polyps Fig 8a: Mysid rearing and culture container Fig 8b: Banks of mysid rearing tanks Ripley s Aquarium of the Smokies Fig 9: Ripley s Aquarium of the Smokies Fig 10: Horizontal kriesel for holding adult jellyfish Fig 11a: Plastic polyp rearing tables Fig 11b: Plastic polyp rearing tables with overhead lights Monterey Aquarium Fig 12: Monterey bay Aquarium, California Fig 13a, b: Ctenophore rearing cylinders Fig 14: Hemispherical pseudo kriesels for rearing ctenophores and jellyfish Fig 15 : Copepod rearing procedure Fig 16: Polyp rearing table with 5 micron canister filter Fig 17: Phytoplankton rearing/culture tubes Florida Aquarium Fig 18: Florida Aquarium Okinawa Aquarium P age

3 Fig 19: Okinawa aquarium, Okinawa Fig 20: Air uplift kriesel with Alatina nr moseri medusa Fig 21: Horizontal square pseudo kriesel Fig 22: Fish egg powder used to enrich Artemia Fig 23: Internal water circulation of kriesel Tropical Biosphere Research Center Fig 24: Tropical Biosphere Research Center Karmo aquarium Fig 25: Karmo aquarium, Karmo Japan Conclusions: Dissemination of information: P age

4 Introduction: This Fellowship funded program enabled me to visit 7 commercial aquariums (5 in the USA and 2 in Japan) as well as one research organization in Japan, to collect and disseminate information on the rearing of cnidarians, (jellyfish), with particular reference to cubozoans (box jellyfish and Irukandji). Over a period of approximately 6 weeks I collected a substantial amount of information on the similarities and differences in cnidarian husbandry between these facilities. Notably there were many things that were almost identical however without exception, each facility used techniques that other groups did not. Overall, the level of expertise that existed for the rearing of cnidarians was substantially higher in America and Japan than it is in Australia, however, it is my belief that Australia has a higher level of skill in relation to cubozoan rearing than elsewhere in the world. However, I believe that many of the skills used in rearing non cubozoan jellyfish in overseas facilities can be usefully transferred to the rearing of cubozoans in not only Australia but the rest of the world. This program could not have been possible without the support of the Churchill Trust and in particular the support from Dr Dorothea Sandars and Irene Lee Churchill fellowship. Similarly I am indebted to all of the people I met and engaged with at all of the facilities visited, but with particular reference to the following people, who unselfishly gave up significant portions of their time to show me the facilities they worked in and the techniques they used but also to show me the culture of the cities and countries in which they live. Their efforts vastly improved the worth of this project and for that I am indebted. Georgia Aquarium; Tennessee Aquarium; Monterey Bay Aquarium; Okinawa Churaumi Aquarium; Tropical Biosphere Research Centre; Karmo Aquarium; Chris Coco and Alistair Dove Matt Hamilton Sarah Halbrend and Tommy Knowles Keiichi Sato Sho Toshino Kazuya Okuizumi and Michiko Tanimoto 4 P age

5 Executive summary Associate Professor Jamie Seymour, (Academic) C/o Australian Institute of Tropical health and Management, James Cook University, Mcgregor road Smithfield, Cairns Australia, Of the 8 organizations visited, the standout facilities were the aquariums, in no order were at Monterey Bay, Karmo, Atlanta and Okinawa. Within these facilities, Chris Coco, Sarah Halbrend, Tommy Knowles, Kazuya Okuizumi and Michiko Tanimoto were amazing in the time they afforded me and the knowledge they imparted. All, without exception gave information freely and were a pleasure to interact with. Overall, cnidarian rearing is very similar but there are very distinct differences between facilities. Without doubt, it would seem imperative that the use of kriesel rearing tanks (or some form of a variation on that theme) are required to successfully rear, if maintain jellyfish. Aquariums in the USA have useful techniques (such as polyp/ephyra collection tanks) that minimize the labor required to collect juvenile jellyfish but lack the integration of many of the new techniques developed and honed by the Japanese aquariums, such as pseudo horizontal kriesel tanks and air lift kreisels held in temperature controlled baths. With that in mind, there would appear to be no facility in either of these countries that has a successful method/s for rearing or maintaining box jellyfish or any species, however, the Japanese aquariums are perhaps closer than others at perfecting the technique, mainly due to the types of tanks they are trialing and the food sources used. It was particularly evident at all facilities that when success was made, that a strong understanding of the biology of the jellyfish being attempt to rear was essential in the success. This is what appears to be missing in the attempts to rear box jellyfish and Irukandji, that is, we as a whole lack the basic biology of the species, such as their major food sources, water temperature and salinity preferences, circadian rhythms etc. Until these data are sourced I feel there will be little if any major advances in maintaining and breeding these animals. As such, the major suggestion from study abroad is that we make a concerted effort to further understand the biology of cubozoans (box and Irukandji jellyfish), and that the results from these studies then be used to direct the way in which we progress in trying to keep these animals in captivity. Since my return for my trip I have already had discussions with staff at the Cairns aquarium and staff from Reef HQ (an aquarium in Townsville) about ways in which jellyfish can be reared. Staff from Reef HQ have visited from Townsville and I have shown them various aspects of new techniques that I have learnt from my visit overseas about rearing of jellyfish. I have also given several seminars (one in America at a conference I attended), about the techniques I was shown and how they can be adapted etc. to increase the success of rearing box and Irukandji jellyfish. I have also given a full break down of the techniques seen and a full copy of this report to my staff members at JCU who rear jellyfish. I am also presently creating a video for the inclusion on my YouTube channel (The Nature of Science, which has a subscriber base of over 65,000 people), to further disseminate the information gathered on this trip. 5 P age

6 Program for Associate Professor Jamie Seymour for Churchill Fellowship in Institution Location Contact person Dates Georgia Atlanta, Georgia Aquarium / USA Tennessee Aquarium Aquarium of the Smokies Monterey Bay Aquarium Chatanooga, Tennessee 88 River Rd, Gatlinburg, TN 37738, USA Monterey, California / USA Chris Coco Michael Vredeveld Alistair Dove Nathan Farnau Chris Schreiber Matt Hamilton Sarah Halbrend Brian Albaum John Lambert Alicia Bitondo Athena Copenhaver Michael Howard Tommy Knowles Wyatt Patry Evan Firl George Matsumoto 27 th August 2 nd September 30th August- 31 st August 31 st August 1 st September 2 nd September 12 th September Florida Aquarium Okinawa Churaumi Aquarium Tropical Biosphere Research Centre Karmo Aquarium Tampa, Florida / USA Motobu, Japan , Motubu, Ishikawa Sesoko, Motobu, Kunigami District, Okinawa Prefecture , Japan Tsuruoka / Japan Ari Fustukjian 13 th September - 18 th September Keiichi Sato 19 th September 22 rd September Sho Toshino 22 nd September 23 rd September Kazuya Okuizumi Hiroshi Miyaki Michiko Tanimoto 23 rd September 28 th September 6 P age

7 Main Body: Georgia Aquarium Fig 1: Georgia aquarium, Atlanta Based in Atlanta, this aquarium has approximately 2.4 million visitors a year. Its history involves an initial one off donation of 250 million US dollars. Approxmately 99% of the income required to run the facility comes from ticket sales, and the aquarium has a not for profit status. The research arm of the aquarium is small compared to its overall size. The floor layout for the aquarium is a daisy flower layout, such that visitors flow from the centre of the facility to satellite displays then move back to the centre to travel to next display. The ticket sales are sufficient to allow the facility to function as well as carry out research. Jellyfish rearing. For all small polyps they use rotifers as the predominant food for two reasons, i) these small polyps cannot handle the size of 24 hr. Artemia (interestingly they have not look at calorific content of 24 hr. old Artemia) but more importantly ii) hydrozoans do not do feed well on rotifers so this keeps hydrozoan numbers down as they out compete the scyphozoans. 7 P age

8 They have notice that elevated phosphate levels as well as high water flow rates can cause bell deformities in Aurelia sp. so they attempt to reduce water flows in kriesels to minimal levels and hold phosphate levels near zero. To induce strobilation in there polyps species they increase temperatures by 5-8 degrees Celsius for a period of 4 weeks. They achieve this by raising the polyp s cultures out of the water in their water tables by placing the chambers on small plastic stands. Their entire water system is a closed system and they make all their own salt water using imported salt and add RO water. Their polyp/ephyra rearing tanks have polyps one end, then an adjoining ephyra tank for collection (fig 2). Fig 2: Polyp holding and ephyra collection tanks The ephyra kreisels have a circular floor not an oval floor, i.e. are a true kriesel not a pseudo-kriesel to decrease the collection of debris on the floor and get good ephyra suspension. Very young ephyra are held in containers with air flow via bubbles to give suspension. This is achieved via long glass tubes placed in the containers with the outlet at the bottom of the container. 8 P age Algae growth is an issue and it is removed by hand from polyp tanks. In ephyra tanks ephyra are moved and tanks are bleach regularly to remove algae, hydrozoans and other

9 unwanted organisms. They use sodium bisulfate as a neutralizer for the bleach. All polyp cultures are kept in low light to reduce algal growth, as are ephyra except those with zooxanthellae, e.g. Cassiopeia, which are fed 24 hr. old Artemia AND held in light. Light or Artemia alone are not sufficient to produce growth in this species. Nitrate and nitrite levels are kept to minimal levels (as a closed system) by running all water in the facilities though huge sulphite towers to covert waste to sulphites. It is unknown what the high levels of sulphites will have on the system at this stage, but they are continuously monitored. All species of scyphozoans polyps are settled on standard PVC polyp plates suspended vertically however they have some cultures that are grown on petri dishes with foam on top so that polyps are supported vertically underneath (figure 3). Fig 3: Plastic substrate containers for settlement of polyps To decrease the unwanted organisms into the polyp and ephyra rearing systems all system water is run through 5 micron inline filter canisters. This has effectively removed hydrozoans and other organisms (e.g. algae) from the system. They appear to get 2-3 weeks out of each inline filter before it needs to be cleaned. Again it is sterilized in bleach, neutralized using sodium biosulphate and then rinsed and put back in line. Flow to the system then goes from the main water system, through the inline filters to polyp/ephyra 9 Page

10 cultures, then overflows from tanks to the water tables, and then drains through cloth filter bags and then back to main system water. The entire polyp and ephyra rearing systems are all done on water tables so that water and over flow from containers into the table. Once ephyra have been moved to kriesels they are then moved off the water tables. All facility water also passes through quad sand filters (a battery of these as water is split and run through separate batteries). Back washing in each quad is automated so that if the pressure increases above a set level the chamber automatically back washes. System water is recycled as much as possibly, being filtered then ozonated then degassed and sent back into the system. Large numbers of extremely large protein skimmers. They have large ozone towers but also run small quantities of ozone through protein skimmers to help bubble creation and thus increase efficiency of the protein skimmers. To measure ozone levels, they have redox probes in line in the inflow and outflow of ozone towers and also at the water entry points for water flow into the main system water entry point. All probes are automated and the final redox probe has overriding control. This then directly controls the ozone concentrations in the facility. They have a full time staff member that maintains the redox probes (i.e. cleaning etc.) for the entire facility. Most probes are cleaned daily. The separate ozone towers have a Mercedes type inlay to increase surface area of the seawater exposure to the ozone to get maximum exposure time and hence maximum sterilization. Once water has passed through ozone towers it runs directly to the degassing towers. 10 P age

11 Although the facility attempts to rear all of its scyphozoan species, they often supplement medusa with wild caught animals. This is limited though as the facility is a long way from water and as such collecting trips are major expenses. They attempt to either introduce new polyp genetics into the cultures (or replace them) every months as cultures stop strobilation and/or the numbers of polyp s crash. These polyps are introduced from other cultures from other aquariums, mainly it seems from two aquariums, predominantly Monterey. Tennessee Aquarium. Fig 4: Tennessee Aquarium, Chattanooga The aquarium has approximately ,000 people a year and is organized so that visitors travel in one direction through the facilities. Requires philanthropic funds on an annual basis to continue to operate (with the first wing of the aquarium built in early 90s (river journey), and the saltwater wing built in 2008/9. Jellyfish displays form a small part of what they do and they devote the equivalent of about 2/3 of a person full time to the maintenance and display of jellyfish. Bleach is the major solution they use for sterilization and they use sodium thiosulphate to naturalize bleach washed containers and tanks, at an approximate 5:1 ration of thiosulphate to bleach. 11 P age

12 They have a food rearing section where they rear mysids (in very small numbers) and also copepods which they use mostly for fish larval rearing. Rearing algae for the food source for copepods. They are routinely using lugols (aqueous iodine; potassium iodine with iodine in water) to induce strobilation in Aurelia (fig 5). Fig 5: Lugol s solution (iodine). Ephyra collection is carried out with containers held in water tables, with the polyp/ephyra containers and a flow through water system and an external catching container for ephyra (fig 6a and 6b). 12 P age

13 Fig 6a: Flow though ephyra collection tank Fig 6b: Flow through tank in-situ with polyp tank They run very high densities of ephyra and medusa in all containers, with little negative effects on the health of the medusa. Kriesel size is important for medusa and ephyra survival i.e. small kriesels for small medusa large kriesels for large medusa. Need the smallest amount of water flow BUT need to keep ephyra or medusa suspended i.e. big kriesels have too much movement for little medusa. They use a mixture of foods for jellies, which includes rotifers, oyster feast, rotifeast, blood worms (fig 7). Fig 7a: Commercially produced dried rotifers for food for jellyfish polyps 13 P age

14 Fig 7b: Commercially produced oyster and rotifer slurry for food for jellyfish polyps They feed medusa and ephyra twice daily, using minimal food amount so that water fouling is a minimal issue. They also do power feeds, i.e. high densities of food for 20 min then complete water change. They ensure that the outflow hole in ephyra tank is well below upper level of screen as the screen can become blocked regular due to food collection and by engineering tanks in this way it decreases the episodes of overflows. Screen size, more importantly the apertures in the screen, in all kriesels is important for medusal development and good bell development. The apertures need to be big enough to let uneaten food out but small enough to not let the medusa get stuck, in essence the bigger the better, however medusa entrapment is important to avoid as this will result in initial bell damage which leads to bell deformity and ultimately death of the medusae. They have investigated the use of ice block food cubes on weekend to decrease labor and time in feeding medusae. Cubes are made up in freshwater so they float as they melt to help keep food suspended, an important function as medusae will not eat food from the floor of the aquaria. These cubes have blood worms, krill, mysids, rotifers which are frozen in freshwater ice cubes. 14 P age

15 They make use of peristaltic pumps to feed mysid cultures. This could be used for ephyra and medusa to autonomies feeding. They drop the food (in this case 24 hr. old Artemia) into the water inflow line so one pump can dose all tanks. They have had issues with clogging but have overcome that by ensuring the water outlet line is of a sufficient bore such that is doesn t get clogged with Artemia. Their Artemia cultures are all exclusively 24 hr. or 48 hr. old naupulia (the latter are enriched) and no on grown Artemia are used. Like all other aquariums growing jellyfish, they have had problems with hydrozoans growing in the system, especially in scyphozoan rearing tanks. They have reduced this by reducing the amount of uneaten Artemia in the system by placing filter socks on the outflow lines in all rearing tanks. Notably they recirculate the water in the rearing facility but do add new water at a small rate such that old and new is mixed with overflow exiting the system to travel to the rest of the entire aquarium water supply. They use bleach as their major sterilant and sterilize every container on regular basis (at least once a week) with bleach at 80 ppm for at least 30 min to an hour. They also supplement feed all their Cassiopeia, again with Artemia, as well as keeping them under metal halide lamps as they have found that lights alone do not allow the medusa to grow. For their rearing of Mysids, which is done at very low numbers, the adults are held in mesh bottom containers in key hole tanks (fig 8). 15 P age

16 Fig 8a: Mysid rearing and culture container Fig 8b: Banks of mysid rearing tanks as juveniles are positively geotrophic and adults are cannibalistic. Thus as the juveniles are born they move through the mesh and away for the adults. Both adults and juveniles are fed Artemia naupulia through the peristaltic system; they do not rear large numbers of mysids in the culture system. The cultures of Cassiopeia polyps they are rearing strobilate all year round and there are no need for cues. 16 P age

17 Every inflow water line in each tank or rearing table has a fluidized bed to decrease algae into the system. I also suspect it removes any free living food, including any rogue Artemia naupuli, from getting into the table and thus helps decrease hydrozoan growth. They have not had to bring in new polyp cultures for all of their scyphozoans for at least a couple of years. This would suggest they have passed through the 3-5 generation genetic bottle neck. All polyp and ephyra cultures are run on water tables. This then means they can run them in ambient room temperatures but still have water temperatures in the rearing vessels at the same temperature as the entire system water without having to heat or chill the cultures. They induce strobilation in the polyps by cooling them. This is achieved by firstly keeping them out of the water on the water tables (at an air temp of about 64F and then they drop the culture vessels into the water on the tables (at temperature of 55-57F) for a couple of weeks then then they start to strobilate. Once this is initiated they raise the vessels back out of the water. They have a single mangrove (Rhizophora sp.) growing in a very small pot in the stingray exhibition. It has been going for 10 yrs. and just produced propagules which they have just planted out. The substrate in which it is planted is separated from the water flow in the system. 17 P age

18 Ripley s Aquarium of the Smokies Fig 9: Ripley s Aquarium of the Smokies. This aquarium is based in Gatlinburg, Tennessee and has approximately 1,000,000 visitors a year and requires philanthropic investment to stay viable. They have a very small jellyfish rearing facility but do have a reasonable display on jellyfish in the aquarium. They have horizontal kreisels (fig 10) that they often use for medusae rearing. Fig 10: Horizontal kriesel for holding adult jellyfish 18 P age

19 These kreisels have a small upwelling in the middle of the tank with circular movement around the outer edges and a vertical mesh overflow (n.b. the flow in water in the picture is usually not going, this is just an artifact of them not using the tank as a kreisel at that point in time). They induce Chrysaora sp. to strobilate using low temperature cues (about 5 o C lower). Again they use water tables raising or lowering culturing vessels to produce changes in water temperature. They have also used large bore PVC tubing to make a stand complete with nally bin containers for the base of the water tables (fig 11). Under this scenario there is nothing to rust. Fig 11a: Plastic polyp rearing tables Fig 11b: Plastic polyp rearing tables with overhead lights 19 P age

20 They are of the belief that continual strobilation decreases fitness of culture and will cause culture crash. As a result they tend to rest their cultures for several months and have a rolling series of cultures, some resting, and some strobilating. This seems to be absent for their Aurelia culture which continual strobilates with no need for cues. It is believed that this culture originated from Japan via Monterey. Unlike other aquariums they are using pseudo, pseudo Kreisels for moon jelly medusa as display tanks (also in their touch tanks for Aurelia). They are using water tables for polyp and ephyra rearing, same as other facilities but are using plastic nally bin type set ups, which may be more flexible in culture rooms with limited space. They are also using bleach as a sterilant for all equipment and use it on a regular basis. They use four horizontal kreisels, all on the same system. One is always off line, so they move medusa once a week from one tub to the next and then bleach one of the tubs, so that there is around three weeks between complete beaching of a tub. This is done to decrease hydrozoans and other organisms in the tanks that could cause mortality to growing medusa. Monterey Aquarium. Fig 12: Monterey bay Aquarium, California 20 P age

21 This aquarium was originally set up by a philanthropic injection of funds from Hewlett Packard foundation. They have strong links with MBARI. They regularly see 1.8 million visitors a year, and the aquarium has a flow through water system, accessing water directly from the ocean. I gave a seminar to the facility entitled Venomous marine creatures in Australia, which was attended by close to 100 staff members and was videoed for showing in future. As a sterilising agent they use bleach at 10% for one hour to sterilise tanks and then neutralise with Sodium Thiosulfate. Over the last couple of years they have decreased the number of jellyfish and species on display, primamrily as their major display on jellyfish is coming to an end. They are now spending a lot of time and effort on maintaining planktonic organisms, such as ctenophores, for display. As such they have closed the life cycle on several species of ctenophores, primarily through the use of large cylinders for rearing (see fig 13). Fig 13a, b: Ctenophore rearing cylinders. 21 P age

22 They use a tube within a tube for ctenophore rearing. Ony one tube has a hole In the side, the others just flow over the edge. Screens on the ctenophore tubes are 50 micron As an alternate food source for many of their gelatinous species they are using larval crabs (planktonic stage) from one of the crab displays. They are also using peristaltic pump for feeding naups to jellfish which are linked to water timers. The naupuli are held in a large volume of water and released via a perastaltic pump into the rearing chambers holding the jellyfish. 20 volunteers). They have approxiametly 5 full time staff members running jelly display (with over They are also using a Hemispherical pseudo kriesel (fig 14) to rear some species, predominantely ctenophores. 22 P age

23 Fig 14: Hemispherical pseudo kriesels for rearing ctenophores and jellyfish. The entire aqaurium systme is a Flow through water system (open cycle) and as such they have little if any issues with water quality. Had issues with survival of juvinile species (fish, sea horses, etc) and used Sanolife mic powder ( They add this to the water that holds the juvenile animals. Increased the survival rate of baby sea horses from 1-2% to over 80. It appears to be primarily a gut conditioner, allowing the relevant gut flora to be established. 23 P age

24 They are also rearing copepods, Parvocalanus crassirostris, (and algae for the copepods) for foods for jellies. Have started their own local culture of copepods which they catch in the bay via a plantkon net (fig 15). Fig 15 : Copepod rearing procedure. They have incredibly high densites of copedpods in the bay which is what makes this possible. They have heard about a new copepod ( which will feed and survive on dead algal pellets. They also Use a 5 micron canister filter on the jelly culture system. When they went to this it decreased worm infestations, algal growth and hydroid growth etc. 24 P age

25 They are also producing 3D printed models to use for teaching and display purposes. This same technology could be used to produce cut aways of cubozoans to show structure as well as for scyphozoa medusae and also for polyps as well as corals. Their original Aurelia culture came from japan, but they have not introduced new material since then but do introduce new polyps from the system into their breeding cultures. Interestingly they collected Aurelia labiate from the bay, but don t rear this species as it does not culture well. On one polyp rearing culture table they have a sump and recirculated water, and have a fine filter bag on outflow line to the sump and also the 5 mm canister filter (Fig 16). Fig 16: Polyp rearing table with 5 micron canister filter It has occurred to me that given cubozoan polyps may do well at lower salinities it may be useful to rear them at low salinities to decrease algal growth. As an aside, the aquarium also breed cephalopods (e.g. flamboyant cuttlefish, nautilus, squid etc.) and do so by bubbling the eggs in modified containers. They often use glass shrimps as live food as well as on grown Artemia for smaller cephalopods. 25 P age

26 They collect a lot of their gelatinous specimens directly from the bay outside of the aquarium. As such this vastly reduces the time and energy needed to keep cultures running. When collecting jellyfish in the bay they often use a procedure called a jelly donuts to cause upwelling currents to bring jellyfish to the surface. Basically this entails driving the power boat at a significant speed in a tight circle. This produces an up-welling current that lifts jellyfish from deeper water to the surface where they can then be collected via a net. They also rear different species of algae for use in growing specimens. They have a prescribed technique which when followed gives a significant return of algae (fig 17). Fig 17: Phytoplankton rearing/culture tubes. They also run a Jelly school every second year, whereby they teach various people about rearing jellyfish. I discussed the possibility of having people from JCU attend in 2019 and the aquarium was receptive to this. 26 P age

27 Florida Aquarium Fig 18: Florida Aquarium They process approximately 800,000 visitors a year. The aquarium is a flow through water system and has a small jellyfish display. They rear Aurelia and Phylorhiza and display Catostylus. They used horizontal cylindrical kriesels for the major display tanks, which are long tubes (acrylic) with top to bottom circular flow along the long axis of the tank. They are setting up new displays which will house Aurelia and will have touch tanks for these jellyfish using the same types of tanks as Ripley s of the Smokies. They do little rearing and that which they do is not significantly different from other aquariums. 27 P age

28 Okinawa Aquarium Fig 19: Okinawa aquarium, Okinawa This marine resort park has approximately 3 million visitors a year and is a not for profit system. Patrons only pay for the aquarium, rest of the park is free (i.e. whales, manatees, etc.). Funded by the Japanese government, plus gate takings from the aquarium and souvenirs and food etc. The jellyfish section rears many species and has a culture of Alatina moseri (an Irukandji causing box jellyfish) from osprey that originated from my research lab. They have reared medusae from polyps (hold polyps at 20 degrees then to 24 degrees for 4 weeks to get metamorphosis, then drop them back to 20 degrees to allow the culture to continue asexually reproduction and hence keep the culture running. They feed these new medusa Artemia (24 hr. old) as well as fish eggs which they collect from their large whale shark tank (the eggs are thought to be mac tuna eggs, approx. 100 um in size). They have only managed to rear the medusa once. The medusa in the kreisels (fig 20) are about 10 mm long, and about 3-4 months old. Feed them once a day. 28 P age

29 Fig 20: Air uplift kriesel with Alatina nr moseri medusa They keep adult Chironex yamaguchi which they catch as adult and can hold them for 1 month but slowly decrease in size, don t seem to go pyramidal though. They feed them once a day with a small fish. Hand feed into tentacles, but have the same issues as we do with feeding with Chironex fleckeri. They cover all feeding utensils with Lycra to avoid firing of nematocyst. The tanks they hold them in have with MINIMUAL water flow and are hemispherical. Medusa often resting on substrate (this species is active during the night and resting during the day). Only have one or two animals per tank and each take is approximately 500 litres in volume. They have had little success in maintaining juveniles, i.e. decrease in size very quickly. They have also had little success with holding adult medusae as well. All animals are collected from the marina via ladle on the end of a pole and they catch them in the ports using lights. They have developed a variation of the kriesel, i.e. square with flow vertical on front and back face (Fig 21). 29 P age

30 Fig 21: Horizontal square pseudo kriesel. They have also modified old square tanks (e.g. display tank) which were not a purpose built kriesel. They also catch Copula sivikisi in the harbor as well but only for small window in year. They enrich all their Artemia with a fish egg powder (fig 22, all in Japanese). Fig 22: Fish egg powder used to enrich Artemia 30 P age

31 All polyps grown in dark, (to reduce algae growth) suggesting zooxanthellae are not necessary, same with medusae. (C.f. Cassiopeia which is grown in light and also fed Artemia). All of the large kriesels etc. have a pump in the system to give water flow and an external water flow as well (fig 23). Fig 23: Internal water circulation of kriesel. External water flow in is minimal. In some of their kreisels they use an air lift to produce the water current, especially for Alatina medusa. They also use little wine fridges for temp control cabinets. This is a cheap solution. Polyps and ephyra are really small and they remove ephyra individually, which is very labor intensive. Note the picture of the ephyra in small containers with bubbles in the little fridges, i.e. water quality not a major issue. 31 P age

32 Tropical Biosphere Research Center Fig 24: Tropical Biosphere Research Center Sho Toshino, a researcher working on box jellyfish. University of the Ryukyus, Sesoko Station, 3422 Sesoko, Motobu, Okinawa , Japan. Sho rears all his polyps in small watch glasses or small Tupperware containers. This means that space requirements are minimal. He is also using small air lift kriesels to grow out medusae. He uses only Artemia to feed polyps and does not enrich them. Has reared C. yamaguchi from single tentacle medusa (felt they were this species as found with other C. yamaguchi) but does not have or has not seen polyps for this species. Chironex yamaguchi has nematocysts on both the bell when they metamorphose as well as nematocyst clusters on tentacle base but lose both as they grow. Has not been able to get chirodropid polyps into culture. On the few occasions he has managed to get spawning here produces creeping polyps but has not managed to get these to settle out to produce sessile polyps. 32 P age

33 He feels that Chironex yamaguchi is nocturnal and rests during the day. He has managed to get C. yamaguchi to spawn in square concrete tanks but these tanks are unsuccessful for rearing of them. He has managed to hold baby C. yamaguchi in plastic milk jugs but has not managed to get them to on grow. He has managed to induce metamorphosis in some carybdeid species by using increased water temperatures for 4 weeks. He also uses cool/hot wine fridges similar to Okinawa aquarium. He has polyps for C. sivikisi, and has also has found adult A. alata on the coastline of Okinawa. Karmo aquarium Fig 25: Karmo aquarium, Karmo Japan. This aquarium used to show a vast array of sea life but changed to displaying predominately jellyfish in an attempt to make it economically viable some 8-10 yrs. ago. Overall the change has been a remarkable success. They presently receive thousand visitors a year. They display over 80 species of jellyfish and attempt to rear the vast majority of them. 33 P age

34 In the jellyfish rearing side of the aquarium they have a very small staff, approximately 5 people who rear jellyfish in a very small space. They use glass beakers and volumetric cylinders to rear ephyra of all species. Within the aquarium itself they have a designated area where by staff can give talks to visitors in the aquarium which is incredibly successful. They also show how nematocysts work by applying vinegar to developing ephyra under the microscope and then stream it to the audience. They were the original creators of the front to back pseudo kreisel where water flow is from front to back with the filter screen on vertical side of the tank. This means the tank can be rectangular and still work as a kreisel. They also designed and built the airlift kreisels, which uses air bubbles to generate water flow but they do not use screens in these tanks and as such there is no flow through water system. They change water once a week in these kriesels. For temperature control of the kriesels, most of the kreisels are held together in tubs, they then heat or cool the surrounding water to allow for different temps thus you only need one heater/chiller for a number of kriesels. For polyp settlement of jellyfish they using large plastic mess gutter guard, which allows large numbers of polyps, still allows for water flow, allows for easy movement of polyps from one tank to another to stimulate strobilation and also allows for easy viewing under a microscope. When changing water in measuring cylinders, they just sieve ephyra into fine fish dip nets and then restock cleaned kreisels, i.e. they are reasonable brutal with the methods they use and the ephyra appear to handle this abuse. 34 P age

35 Water movement into kreisels needs to be the MINIMUM necessary to keep jellyfish suspended. Due to their delicate nature excessive water flow results in broken oral arms etc. and greatly increases the mortality rate. They have managed to rear Carybdea brevipedalia from polyps, feeding them live Artemia and also frozen copepods, but they have also been using live rotifers for many of the very small cubopolyps they have in culture. They also feel there is no polyp stage for Pelagia noctoluca and they have closed the life cycle on Pelagia. They have also been rearing ctenophores, have closed the life cycle, again using rotifers as the feeding source early on as well as Artemia for large specimens. When feeding jellyfish medusa, they do so twice a day, just pouring them into the top of the kreisels, with no drip feed. They collecting ephyra by hand from the polyp containers, using glass beakers etc., all with simple bulbs on the end of long glass pipettes. This is a very labor intensive process. The entire aquarium is a flow through water system taking water directly from the ocean and returning it to the ocean. They use no ozone for water sterilization and this is almost certainly a reflection of the good ocean water quality and the high throughputs of water with very little retention time. All the water that is collected from the ocean runs into three spate lines, each with its own temperature control. This allows them to run three very different temperatures without the need for many small heaters or chillers for individual tanks. They have a very large number of species of Aurelia from all over the world but do not have any of the Australian species. We are looking at setting up a collaboration between JCU and Karmo to swap species. 35 P age

36 They have the largest kreisel built on display, 5 m in diameter by 1.5 m deep which houses over 3000 individual Aurelia. They using increases in water temperature to induce strobilation in the majority of their scyphozoans and they are reasonably brutal with the water temperature changes, e.g. Increasing water temperatures by 5-7 degrees for 4 weeks is not uncommon. They are consistently looking at better ways to display jellyfish to increase the interaction with visitors. One such example is the use of UV light on Aquoria to show the fluorescence. All polyps cultures are held in the dark to prevent algal growth, except Cassiopeia which is held in light. The use both light and Artemia for feeding of Cassiopeia medusae. They use no on-grown Artemia, instead just using 24 hr. old naupulia. They have had several attempts at keeping Chironex yamaguchi alive but have at this stage not been successful. They also believe that Chironex yamaguchi is active at night and inactive during the day. Director firm believer in observations are very important to determine the best way to rear and hold jellyfish and as such allows for staff to spend time in a day recording observations etc. They consistently drop temperatures in many of their display tanks for species such as Chrysaora and other long tentacle jellies to stop tentacle tangles and also to prolong length of medusas life. They have developed new upwelling cylindrical tanks (see picture) which are not as successful as they hoped and they are looking at modifying them to improve their efficiency. 36 P age

37 Often change the water direction in the pseudo kriesels so that jellyfish do not go in the same direction. They can do this as the tanks do not use spray bars but are using drill holes. In the big pseudo display kriesels the holes are above and below the screens and are plumbed in so you can use one set or the other, i.e. can change direction. Note the smaller kriesels are pseudo/pseudo horizontal kriesels. There are cameras on the side of polyp rearing tanks with gutter guard so that people can see the strobilation etc. VERY high density of polyps. All portable kreisels are held in large water tubs with temperature controlled water which means that only one heater chiller is needed for many kreisels. The aquarium system was rebuilt in 2013 to display jellyfish so in the grand scheme of things it is still quite young. Most of the species are 3 rd to 4 th generation and they may experience major issues in the next couple of years due to genetic bottle necking. 37 P age

38 Conclusions: It would appear that the techniques used by the USA and Japan have several things in common, such as the necessity to use kreisels to successfully rearing any type of jellyfish, however there are different techniques used in both countries that could usefully be combined to produce a more efficient and successful rearing strategy for jellyfish. In short, the America system is geared to produce large volumes of jellyfish but is very labor intensive. Conversely, the Japanese system is very technologically rich, but suffers from some parts of the rearing system that are very labor intensive (such as the collection of ephyra that is done by hand, unlike the USA system where they are mass harvested). By combining the use of new kriesel shapes and technology employed by the Japanese and the mass harvesting techniques used by the USA, I believe a much more efficient and successful system can be implemented. It is without doubt that the Japanese have made a quantum leap forward in rearing of cnidarians and it would appear that this has come about by them spending a lot of time first working out the general biology of the species that is to be reared. This was particularly evident in the Karmo aquarium where the director of the facilities promotes the idea that observations of what is happening in the cultures is very important and should be regularly reported. This is something that I believe is paramount in any aquarium system if cnidarian husbandry is to be successful in the long term. Overall, I felt that Australia has a far better understanding of the biology of box and Irukandji jellyfish and by using the techniques used for rearing other jellyfish in America and japan that we can successfully rear these animals. 38 P age

39 Dissemination of information: Since my return for my trip I have already had discussions with staff at the Cairns aquarium and staff from Reef HQ (an aquarium in Townsville) about ways in which jellyfish can be reared. Staff from Reef HQ have visited from Townsville and I have shown them various aspects of new techniques that I have learnt from my visit overseas about rearing of jellyfish. I have also given several seminars (one in America at a conference I attended), about the techniques I was shown and how they can be adapted etc. to increase the success of rearing box and Irukandji jellyfish. I have also given a full break down of the techniques seen and a full copy of this report to my staff members at JCU who rear jellyfish. I am also presently creating a video for the inclusion on my YouTube channel (The Nature of Science, which has a subscriber base of over 65,000 people), to further disseminate the information gathered on this trip. 39 P age