Rising Tide Conservation Updates

Figure. Photos of Colurella adriatica;
a potential new live feed for both
marine and freshwater fish larvae.

This post is in response to requests for more information about Colurella adriatica. As previously stated, we’ve examined salinity and found that although they tolerate a wide range, optimal performance is at 15-20 g/L (ppt). For feeding marine fish larvae this is likely going to be the culture salinity as acute acclimation to full strength seawater is good and this will save on salt. Colurella also grows well at 5 g/L and therefore when growing them for freshwater fish, this is the recommended salinity. Thus far, attempts to grow Colurella in 0 g/L freshwater have yielded poor results. The only other culture parameter tested so far has been diet. An industry partner works as a microbiologist and isolates bacteria. He had some freeze-dried bacteria that he wanted us to test. When solely fed freeze-dried bacteria the Colurellapopulations survived. When compared to those Colurella fed algae paste (Nanno 3600™; Reed Mariculture), the ones fed freeze-dried bacteria initially grew better than those fed paste. However, after 4 days the Colurella fed paste had significantly greater growth. The results of this trial are still being evaluated, as is optimal diet, but Colurella’s ability to be fed, and survive on, freeze-dried bacteria seems feasible. Other culture parameters haven’t been tested yet, but we keep our populations at ~78° F with gentle aeration and can reach ~500 rotifers per mL with a population growth rate half of what is achieved with Brachionus sp. rotifers. Hopefully, once we know more about this species we can increase the population density and growth rate.

As stated in a previous post, Colurella has been fed to and consumed by a number of marine fish larvae. In fact, it is easier to mention the one that has not consumed it: green chromis. Digestibility has been an issue for us when using Colurella as prey for marine fish larvae. We've actually seen live, undigested Colurella being passed through the gut of marine fish larvae. After talking with Patrick Sorgeloos, his suggestion was to feed less and increase the residence time in the gut. We'd always fed high densities. One of the unique attributes of Pacific blue tang larvae is their ability to survive heavy water movement (usually in the form of aeration), even to the point of being unable to feed (more on this in a future post). One of the tests we’ve run to increase digestion was to feed them Colurella followed by periods of heavy aeration so they couldn’t feed. What we found were digested Colurella in the gut of Pacific blue tang larvae. The results were encouraging and recent tests have focused on ways to increase residence time of Colurellain the gut of marine fish larvae. Digestibility of Colurella is not a problem for freshwater fish larvae. To date, we've fed them to bala shark, dwarf gourami, lemon tetra, and red-eye tetra larvae and they've all survived. Recently a population of Colurella was supplied to a freshwater fish farmer in the hopes of more advantageous results during larval rearing.

Perhaps the most exciting information is that in the next few weeks we’ll be awarded a grant to look at the culture conditions and larval feeding of Colurella(and Oithona colcarva; our marine cyclopoid copepod). Whether this will be in the form of hiring someone or promoting someone at our facility remains to be seen, but having someone focused solely on answering these questions will help us obtain valid information quickly.

The Rising Tide team at the Tropical Aquaculture Laboratory

Figure1. The new larval rearing room at TAL; showing the
120 Ltanks used to grow octopi in. We've also recently tested
our fish species in them which we'll talk about next time.

At the Tropical Aquaculture Lab in Ruskin, we’ve been running into lots of bottlenecks in the early larval development of some of the Rising Tide species we’ve been working on. We believe these issues were exacerbated due to our current larval rearing systems being inadequate to provide the pristine water quality necessary for larvae to survive. Because of this, we’ve spent the past several months upgrading our facilities, to what we believe will be an important step toward significant advancements in captive raised marine ornamentals.

Figure 2. 22 day old common
octopus paralarvae

Upon nearing completion of the new system, we were approached by Mote Marine Laboratory’s cephalopod specialist Brian Siegel; their common octopus (Octopus vulgaris) had spawned, and they were curious if we would be interested at giving them a go. Rising Tide’s focus is primarily on the captive propagation of marine fish species, but we thought this would be a great way to test out our new larval rearing system. Common octopi have been reared in captivity at several institutions around the world, but with very low survival, believed to be due to poor water quality and nutrition. We’re hopeful the improvements we’ve made to our system will allow us to have some success with these challenging cephalopods.

Cephalopods have incredible abilities to adapt to their environment using chromatophores, which are pigment-containing and light-reflecting organelles found within their cells. They allow the octopi to communicate as well as camouflage to their environment. Even as paralarvae, these common octopi can create beautiful patterns with their chromatophores, as seen here:

Common octopus paralarvae have a voracious appetite for crustacean zoea in their natural environment, and have been successfully reared by substituting with Artemia nauplii as a prey item throughout development. By providing them with a constant supply of pristine seawater along with microalgae and Artemia nauplii, we’ve reached 28 days post hatch today. We’re hopeful they will remain strong enough to survive to settlement.

The Rising Tide team at the Tropical Aquaculture Laboratory

Figure. 17 day post hatch Pacific blue tang larva. Credit: Kevin Barden.

The newly revamped larval rearing room has been up and running since early May. In truth, there are still a few things we’d like to add to the filtration system, but that hasn’t stopped us from stocking eggs into the system as we get them. One of the first larval rearing attempts was performed with Pacific Blue tangs. We got roughly 4000 eggs; which we then stocked into a 210 liter tank (55 gallons). This worked out to a density of roughly 20 eggs / liter. For the first three days the water flow entering the tank was 750 mL/min; which theoretically works out to ~5 tank turnovers per day. At first feeding the flow rate was increased to 2.75 L/min; which works out to ~20 tank turnovers per day. It was left at that rate for the duration of the trial. This high water flow was inspired by Chad Callan’s recent success with yellow tang larvae. We also instituted a moderate air flow with two air stones pumping ~250 mL/min each. Both created a significant amount of water movement within and through the tank. The larvae were also subjected to a photoperiod of 14 hours light and 10 hours dark. Because of the high water flow we fed the larvae Parvocalanus nauplii (<100 microns) at a density of 2/mL twice daily; which is all we had left over after supplying Jon’s milletseed butterflyfish trials. Although the water quality was not optimal as ammonia and nitrite were detected in the system (albeit low values), the performance of the larvae was greater than we have seen in previous attempts. Typically we would lose the majority of the larvae by ~6 days post hatch. During this trial the majority of the larvae made it through that bottleneck and survived until ~10 days post hatch, with the last surviving to 20 days post hatch. From the picture of a 17 day post hatch larva (the last taken) you can see the beginnings of the hypural plates forming which would preclude flexion. However, we can’t say for sure. What we can say is that these results were promising and hopefully in the not-too-distant future as the system becomes more stabilized, the live feeds become more plentiful and nutritious (new microalgae production system….which we’ll talk about later…), and the list of parameters tested becomes smaller we will have more advances to talk about. But for now it’s just one small step forward.

The Rising Tide team at the Tropical Aquaculture Laboratory

Figure 1. Culture of bacteria (Pseudomonas sp.??) on marine
agar isolated from larval rearing tanks at OI.

Aloha everyone!

It’s been a while since my last post, but it’s been a busy few months. Though it's the kind of busy you don't realize until you sit down and catch your breath. It’s been a lot of fun spending my days in the lab working with everyone learning new things.

Figure 2. Sample of Parvocalanus nauplii on TCBS agar that
was fed to yellow tang larvae.

Since we are still observing relatively high mortality just past first feeding, my work at the Oceanic Institute is focused on bacterial population analysis and application of probiotics to our yellow tang larval rearing tanks. The first month of summer was spent looking at the growth of our live feeds with the addition of probiotics, which appear to have no effect on their survival or growth. This is great news for us! We’ve started to culture our copepods in probiotic-enriched water for larval rearing trials starting July!

Figure 3. Gel electrophoresis of 12 different
bacteria isolated from systems at OI.

My thesis is looking at the identification of bacteria in our culture environments and live feeds and their impact on larval survival. Much of June has been spent practicing different plating techniques, isolating different colonies and running PCR. It’s been very exciting, as there are over 15 different colonies that I’ve isolated and am now working to identify them. This will hopefully give us insight into the bacterial communities in our rearing tanks and any possible pathogenic bacteria that may be affecting yellow tang survival.

In one of my first trials a bright pink bacteria was growing in the tanks. I was able to sample it and isolate it on marine agar. Hopefully in a week or so I will be able to sequence it and determine exactly what species is growing in our hatchery! The unanimous hypothesis is that it’s a Pseudomonas sp., so everyone is very excited to see if they are right! Bets have been placed.

I’m excited to continue larval rearing trials with the probiotics in July to see if they help us increase survival past first feeding! Fingers crossed!

Emma

The University of Florida’s Indian River Research and Education Center (IRREC) is the latest research facility to join our growing Rising Tide family. Dr. Cortney Ohs heads up the Aquaculture Research and Demonstration Facility at IRREC and has made leaps and bounds in the realms of marine baitfish, marine live feeds, and brood nutrition research since joining UF in 2005. His expertise and expansive facility will greatly enhance the progress desired in the world of marine ornamental fish research.

Figure. Golden Trevally grown at IRREC. Eggs were spawned from
broodstock received from SeaWorld Orlando.

About a year ago, Cortney began his involvement with a shipment of golden trevally broodstock from SeaWorld Orlando. He has since raised 1000’s of them to the juvenile phase, the details of which will be presented in a future blog post. More recently he has acquired funding that will bring green chromis broodstock to his facility so he and his team can begin to address the production protocols required to make this heavily imported species an aquaculture reality. TAL and IRREC will be working together closely on this species as well as the Pacific blue tang. Cortney is currently working on getting Pacific blue tang broodstock so we can double our research efforts and continue to understand the parameters necessary to make this fish a captive bred species as well. In addition, he will also be receiving shipments of eggs from public aquariums, targeting specific species of interest.

I am personally excited to have Cortney added to the expanding list of Rising Tide research facilities as I obtained my master’s degree studying in his lab. Try not to hold that against him though, as he did the best he could J. It is truly an exciting time for Rising Tide as it continues to grow and the separate teams continue to work together, propelling the research forward.

Eric Cassiano and the Rising Tide team at TAL

Figure 1. Golden trevally eggs near hatching.

We were excited to receive 20 mature golden trevally from SeaWorld Orlando nearly a year ago. We distributed 10 fish each into two large recirculating systems. We expected to have fish spawning within a couple weeks, but after nearly a month of no spawning activity we concluded the fish were likely regressing due to transport and handling stresses. We decided to forgo any more spawning procedures until earlier this year, once the fish had become better acclimated to their new setting and temperatures were in the range reported for spawning. This paid off in mid-April after daily ambient temperatures were averaging close to 26°C and conditioned females were verified through cannulation. We administered spawning hormones to all 10 fish within that tank and obtained three spawns occurring 48, 72, and 96 hours after hormone administration. The first spawn contained mostly sinking (unfertilized) eggs but the next two spawns each contained a majority of neutrally buoyant eggs (~0.7 mm diameter). Hatching occurred quickly (~18 hours) with roughly 60,000 larvae hatched from the second spawn and 36,000 from the third spawn.

Figure 2. 14 days post hatch golden trevally larva.

Larvae were stocked into multiple 104 L tanks supplied with flow-through seawater to exchange a minimum of two tank volumes of water daily. Larvae from the second spawn were stocked into three tanks at nearly 15,000 larvae/tank and larvae from the third spawn were stocked into two tanks at a density near 18,000 larvae/tank. Development was rapid and larvae had fully functioning mouthparts within two days post hatch (dph). We fed the larvae enriched (Ori-Green) rotifers at 10-15 rotifers/mL daily until 25 dph. We also fed the larvae copepod nauplii (Parvocalanussp.) at 2 naups/mL daily until 10 dph. By 11 dph, most larvae were able to feed on Artemia nauplii and were fed them at 4 Artemia/mL. We used green water techniques by inoculating larval tanks with live T-ISO (~100,000 cells/mL) up to 25 dph. We began weaning the fish onto a dry diet (Otohime B1-B2) around 15 dph, and after 30 dph fish were feeding solely on the dry diet. During these trials, swim bladder inflation began at 5 dph, fin ray branching at 9 dph, and flexion at 14 dph. The typical black bar pattern and gold coloration could be seen developing as early as 20 dph with all larvae having reached metamorphosis by 30 dph. We observed a mean survival to metamorphosis around 6.5% and obtained over 3,200 juveniles. We restocked them into recirculating systems and raised them for a couple more weeks before they were shipped off to SeaWorld at 45-46 dph around 3.8 cm fork length and 0.94 g.

Figure 3. 30 days post hatch golden trevally larva beginning
to display black bars.

On multiple occasions we’ve administered hormones to both tanks of brood fish and have observed spawning to occur 48-96 hours after administration every time. The quality of spawns has been somewhat variable. We believe golden trevally commercial scale culture to be highly feasible and could be further improved by defining larval culture requirements and optimizing brood fish spawning procedures. We look forward to receiving new species to work with and hope to overcome any difficulties that might inhibit their aquaculture potential.

Figure 4. 45 days post hatch golden trevally juveniles.

Aquaculture lab at the University of Florida Indian River Research and Education Center in Fort Pierce, FL (Dr. Cortney Ohs, Dr. Jason Broach, Bryan Danson, Dan Elefante, Scott Grabe, Andrew Palau, and Audrey Beany)

Hello Everybody! My name is Joe Frith and I have been interning here at the Tropical Aquaculture Laboratory in Ruskin, FL for the past 2 months. I would first like to say “thank you” to Dr. Judy St. Leger, Eric, Kevin, Roy, Craig, Jon and the rest of the staff here at the Lab for giving me this opportunity and making this a meaningful experience. I’m currently an undergraduate at the University of Missouri-Columbia completing my degree in Fisheries and Wildlife with a minor in Biology. As a child growing up in the woods of Missouri I was always very intrigued by the natural world and usually had several different aquariums spread throughout my house at any one time. My interest in the aquatic world slowly evolved from freshwater aquariums to saltwater aquariums to eventually trying my hand at breeding the Bluestripe pipefish (Doryrhamphus excisus), which I had help with from Matt Pederson and the other members at MarineBreeders.org. It was back in February of this year, after reading posts on the Rising Tide blog that I decided to contact Dr. St. Leger about possible internships they may be awarding for the summer. I received an email shortly after and we soon started laying the groundwork for me to become an intern at TAL. What was once a dream was now a reality.

Over the course of this summer I have helped the Rising Tide team with a number of different projects ranging from Pacific blue tang and emperor angelfish spawning to water quality refinement in an attempt to increase spawning and overall health of all brood fish. Specifically I constructed an algae scrubbing device, complete with mangroves, which has made a significant impact on lower the nitrate levels in the fish growout system (the details of which will be discussed in a future blog). In addition I have learned a lot about the whole marine fish larval rearing process including egg collection, egg counting, stocking and density, and important first food items such as copepod nauplii and rotifers. And if I wasn’t working on any one of these projects I was traveling alongside Dr. Roy Yanong to one of the many aquaculture farms here in the Ruskin area.

This experience has opened my eyes even further to the wonderful world of aquaculture and I can’t think of any other way I would’ve rather spent my summer. With all of the knowledge and insight I have gained in the past couple of months I hope to continue on in this field and hopefully make some great discoveries.

Another big thanks to the Rising Tide team for such an awesome experience!

Best Regards,

Joe Frith

Figure. Samantha Groene in the Rising Tide booth at MACNA 2014.

Hello Everyone!

My name is Samantha Groene, and I am a biological technician at UF-TAL. I’ve been with the lab for almost two years, but this is my first official introduction on the Rising Tide Conservation blog. This past week, some of you might have seen me in Denver. The annual Marine Aquarium Conference of North America (MACNA) took place in Denver, Colorado this year, and I had the privilege of representing Rising Tide at the conference!

This year's MACNA was quite the experience! I met so many wonderful people, made a lot of new contacts, and had an overall great time. MACNA is a great opportunity for Rising Tide to be able to communicate the importance of aquaculture to hobbyists and help foster a better future for the critters that we all love. It was very rewarding raising awareness for Rising Tide -- meeting hobbyists, vendors, and exhibitors and sharing with them a cause that is so important for our hobby and our reefs.

I brought with me to MACNA some of our F1 semicircle angelfish to put on display at the Rising Tide booth and at the Boyd Enterprises booth. These fish were some of the stars of the show, and later were raffled off (along with a complete aquarium set-up and other livestock/drygood goodies) to two lucky winners. Of course, there were a lot of other highlights at MACNA. I am sure many of you have heard, but the announcement at MACNA of Karen Brittain’s success rearing the Masked Angelfish (Genicanthus personatus) pretty much stole the spotlight at this year’s conference. However, I will leave it to Karen to apprise you all of the juicy details of that larviculture endeavor.

I would like to thank the wonderful sponsors and people who helped make Rising Tide's presence at MACNA possible and made the event such a success. Specifically, I would like to thank the SeaWorld & Busch Gardens Conservation Fund, Boyd Enterprises, the Denver MACNA Committee, and everyone that donated items for the aquariums that we raffled off at MACNA (thank you JBJ, Martin Moe, and A & M Aquaculture!). I really appreciate all of your support and generosity! All of you helped to make MACNA awesome, and I am very grateful for the opportunity that I was given to serve as the Rising Tide Ambassador at this year’s conference.

I am very happy to have a job where I feel like I make a difference in this world for the better, and it was a great pleasure being able to share my work with MACNA.

Until next time!

~Samantha

Figure. Dr. Matthew DiMaggio joins TAL and Rising Tide.

Matt DiMaggio joined the University of Florida’s Tropical Aquaculture Laboratory in 2014 as an assistant professor. His research program focuses on the culture of ornamental fish species in Florida and he works closely with the local industry to identify opportunities for optimization and innovation. Dr. DiMaggio has a broad foundation in the field of aquaculture, having conducted research with both marine and freshwater species produced for food, bait, and ornamental purposes. His previous investigations have focused on a myriad of applied culture aspects including live feed production, larval rearing, and induced spawning. Additionally, elucidation of basic physiological responses within a species can provide an opportunity for intervention or manipulation to achieve desired outcomes in a production setting. Consequently, reproductive endocrinology, stress physiology, and osmoregulation, are areas of particular interest to him due to their importance for the successful propagation of fishes in captivity. Matt is very excited to contribute to the ongoing research efforts of Rising Tide and he believes that the open dialogue fostered through this collaboration will help to accelerate the commercialization of many of these challenging marine species.

Dr. DiMaggio is currently accepting applications for a four year PhD research assistantship investigating production methods for ornamental fish species in Florida. Please follow the link below for further information http://sfrc.ufl.edu/?p=9997 .

The Rising Tide team at the Tropical Aquaculture Laboratory

Figure 1. 25 day post hatch Purple Masked Angelfish larva.

Over the past year while working on our Rising Tide project, the larval rearing work has focused on the Purple Masked Angelfish Paracentropyge venusta. We had success on our fifth rearing trial in getting the larvae to the juvenile stage. That larval trial started in November of 2013 and the success was most likely brought about through the use of wild plankton collected from Kaneohe Bay. Plankton was collected almost daily in an effort to provide the larval fish with the necessary nutrients to get them through the larval phases, past metamorphosis and into the juvenile stage. Although we were happy with this accomplishment it meant that larval rearing of this species might be dependent and only possible in areas near a source of wild plankton. In an effort to make larval rearing successful in any location our next step was to try and rear the P. venusta using only cultured food items.

Figure 2. 44 day post hatch Purple Masked Angelfish larva.

On our third try while using only cultured foods for the P. venusta larvae we had success again to the juvenile stage. This larval run, “Trial 8” started on June 28, 2014 and the juveniles are currently just over three months old wearing their beautiful yellow and blue colors and are fully transitioned onto frozen and flake foods. The food items used for this trial were the calanoid copepod, Parvocalanus crassirostris, the rotifer, Brachionus plicatilis, and thebrine shrimp Artemia salina. We were pleasantly surprised that this larval run was on a faster track as compared with our successful wild plankton fed larval run which was quite long. The temperature of this run averaged 26C whereas out trial 5 temperature averaged 25C and this of course could be the reason for faster larval development. We also had a better percent survival with Trial 8 showing 20% survival at day 40 compared to trial 5 at 8.5% survival at day 40. The larvae in Trial 8 were able to capture larger prey starting at day 12 while the larvae in Trial 5 were closer to day 30 when they were able to catch larger prey. The transition to non living foods for the fish in trial 5 took place at 137 days old, which is more than six weeks longer than the fish in trial 8! So not only is it possible to rear these angelfish on only cultured foods, they actually did better on it in terms of survival and development through the larval phase.

October brings to an end the year I had working as part of the Rising Tide team. As I conclude this year I hope that those of you out there who are interested in the captive rearing of marine fish will continue on with what we have learned here. I feel that the small scale breeder can make a significant difference in the numbers and species of fish raised in captivity and I encourage you all to continue on with your efforts. I truly appreciate having been involved in a Rising Tide project and I’m extremely grateful to Rising Tide Conservation for giving me the opportunity to focus solely on marine ornamentals this past year.

Mahalo!

Karen

Figure 1. Graduate Student Isaac Lee.

I would like to introduce my two new M.S. students who will be working with Rising Tide. The first is Isaac Lee who started his first semester this fall and is working towards his Master’s degree at the University of Florida’s Indian River Research and Education Center (IRREC). Isaac received his B.A. degree in Biology from Colgate University in 2013. He has had a passion for marine aquaria for years and over the past year he worked at the Long Island Aquarium in Riverhead. He learned about aquaculture of marine ornamentals and how to culture live food organisms.

Figure 2. Graduate Student Carter Cyr.

The second is Carter Cyr who also just started this fall and is working towards his Master’s degree at IRREC. He received his B.S. degree in 2013 from Roger Williams University in Rhode Island where he majored in Marine Biology and worked as a research assistant working with marine ornamentals and live feeds. He grew up in Southern Maine and has had a strong attachment to the aquarium hobby for as long as he can recall. Over the past four years he developed a strong passion for aquaculture.

While they are at UF, they will focus their research efforts on culturing various marine ornamental fish species including broodstock reproduction, and defining optimal culture parameters and feeding regimes for all stages of development to produce market sized fish. Additionally, AZA public aquaria around the U.S. will be shipping collected eggs from their exhibit tanks so we can also define optimal feeding and culture parameters. Results will be shared with researchers and private producers to expand production of marine ornamental fishes.

We would like to thank Rising Tide for funding both of these graduate student positions.

Thank you,

Cortney Ohs, Ph.D.

Associate Professor – Aquaculture

University of Florida

New students contact information:

University of Florida

Indian River Research and Education Center

2199 South Rock Road

Fort Pierce, FL 34945

772-468-3922 ext. 135

email: ilee0913@ufl.edu

email: ccyr399@ufl.edu

Figure 1. Captive bred Porkfish juvenile available from
FishEye Aquaculture.

Three years ago we posted a blog stating the commercial production potential of Porkfish, Anisotremis virginicus (Porkfish Protocol – Rising Tide’s First Commercial Species). As you’ll recall, researchers at the Tropical Aquaculture Laboratory collected eggs spawned at SeaWorld Orlando and grew them to the juvenile phase and beyond. This was not the first time that Porkfish had been grown in captivity (again credit goes to Martin Moe and company). It was, however, the first time that Porkfish had been grown from eggs spawned in captivity using standard commercial production protocols; including the use of hatchery grown live feeds (rotifers and Artemia). This proved inspiring to one of Rising Tide’s industry partners who decided to add this fish to their list of available species.

Figure 2. Captive bred Porkfish juveniles available from
FishEye Aquaculture.

Jonathan Foster of FishEye Aquaculture is making available for the first time aquacultured Porkfish based on the information provided to him via Rising Tide. Shortly after that Rising Tide success, Jonathan acquired Porkfish broodstock (each around 12-15” in length and weighing up to 2 lbs) in the hopes of spawning them. For the past three years he has been conditioning them and waiting….and waiting….and waiting. He confided in us that they may, indeed, need a public aquarium sized tank to spawn. If you’ve been to a public aquarium then you’ll know that those tanks are quite large and not realistic for his facility. Then, as he describes it “late one evening, while checking on our breeders, I noticed quite a bit of commotion and splashing coming from their tank…they were spawning! And here we are today, collecting eggs frequently, and raising Porkfish!”. This marks the first time that this species has been conditioned, spawned, eggs hatched and larvae grown all in one facility; increasing the number of pelagic spawning species available from FishEye Aquaculture to four.

This is a great example of the goal put forth by Rising Tide; making all marine ornamental fish species an aquaculture reality. It’s also a great example of what can be accomplished given time, perseverance, and collaboration. Our hats are off to you Jonathan for believing in Rising Tide and those that wish to move forward. One day it’ll be captive bred tangs coming out of your facility…that’s our goal.

The Rising Tide team at the Tropical Aquaculture Laboratory

Figure 1. Halichoeres melanurus egg on a 1 mm Sedgewick
Rafter cell.

Here at the Tropical Aquaculture Lab we’re very fortunate to have the opportunity to work in a field we’re truly passionate about. That passion inspires me to not only work on captive breeding of marine species here at work, but to also explore other fish by working from home. I’m pleased to announce that the first project I’ve taken on as an at-home aquaculturist resulted in the successful captive rearing of the melanurus wrasse, Halichoeres melanurus, using only cultured prey items. Although only a few fish were brought through metamorphosis, survival should be higher when larvae are raised in the controlled environment of a dedicated facility as opposed to the chaos of a household living room. I strongly believe this fish, and others in this genus, will have significant commercial potential. We now have broodstock at the Tropical Aquaculture Lab because of this early success. The work done so far will stand as strong supportive evidence to move forward with other wrasses as well.

Figure 2. First feeding (~3 days post hatch) Halichoeres
melanurus larva on a 1 mm Sedgewick Rafter cell.

This species is a protogynous hermaphrodite, meaning fish transition from females to males as they mature based on social structure. Females can be identified by the presence of the third black spot at the front of the dorsal fin. The first step these fish make in transitioning from female to male is the loss of that particular spot, so this acts as a great way to identify females. Females can get along fine in groups, however males will compete for territory and only the largest terminal phase male will survive. Spawning these fish in small harems of one terminal phase male with three to four females seemed to work well for me.

One to two hours before the tank lights turned off the male would rise to the highest point of structure in the tank and begin a vibrant display for the females followed by continuous chasing. The male would then find an accepting female and the pair would spawn hundreds up to several thousand pelagic eggs into the water column. The eggs were about 660µm in diameter. Despite this small size, larvae hatch out relatively large (~2.5mm) but with a very small mouth gape (~125µm). Larvae were reared in a static 5 gallon aquarium and were ready to feed at 3dph (days post hatch). At that point, the rearing water was darkened with T-ISO and larvae were fed Parvocalanus crassirostris nauplii at 1-2 nauplii/mL. Lights were on continuously until larvae were 12dph and over the next 8 days lights were transitioned down to a 14 hour light: 10 hour dark schedule. Varying size fractions of copepod nauplii were maintained in the tank throughout the rearing process and at 14dph Otohime A micro diet (75-250µm size) began being fed to larvae. Larvae reached flexion by 15dph (see video) and were settled juveniles by 22dph.

With work on this species now being conducted here at the Tropical Aquaculture Laboratory, we look forward to bringing more information on optimized rearing protocols for this species in the near future.

Kevin Barden

The Rising Tide Team at the Tropical Aquaculture Laboratory

One of our first Rising Tide successes was harvesting eggs from Columbus Zoo and Aquarium (CZA), shipping them to UF’s Tropical Aquaculture Lab, and successfully raising what turned out to be semicircle angelfish. We had samples from that first cohort DNA analyzed for identification. We have since raised multiple cohorts shipped to us from CZA; which has been well documented in previous blog posts (late 2011-early 2012). Ramon Villaverde at CZA has also raised multiple cohorts of angelfish in house. When space got limited we arranged for those juvenile angelfish to be sent to public aquariums which not only had adequate space to house them, but also could effectively inform the public about Rising Tide’s endeavors. We were always curious what other Pomancanthus species (if any) may be spawning in that exhibit. During that time CZA housed two Pomacanthus semicirculatus, two P. annularis, one P. asfur, one P. imperator, two P. maculosus, and two P. xanthometapon in their Discovery Reef exhibit. We have kept some angelfish from those previous spawns and although we definitely have some semicircle angelfish, we also have angelfish displaying coloration not indicative of that species. Below you will find a series of photographs of angelfish on display in public aquariums as well as some from our own facility. Tell us what you think?

Figure 1. Angelfish (2-3 years old) on display at Columbus Zoo and Aquarium. Photo credit: Ramon Villaverde.

Figure 2. Two angelfish (2-3 years old) on display at SeaWorld Orlando. Photo credit: Joe Moynihan.

Figure 3. Angelfish (2-3 years old) on display at SeaWorld Orlando. Photo credit: Joe Moynihan.

Figure 4. Angelfish (~2 years old) on display at SeaWorld San Antonio. Figure 4 and 5 are the same fish. Photo credit: Nick Ireland.

Figure 5. Angelfish (~2 years old) on display at SeaWorld San Antonio. Figure 4 and 5 are the same fish. Photo credit: Nick Ireland.

Figure 6. Angelfish (~1.5 years old) kept at UF's Tropical Aquaculture Lab. Photo credit: Kevin Barden.

Figure 7. Angelfish (~3 years old) kept at UF's Tropical Aquaculture Lab. Photo credit: Kevin Barden.

A student at Scripps Institution of Oceanography, I’m currently working through a Masters program in Marine Biodiversity and Conservation. I graduated from Boston College in 2008 with a Bachelor of Science in Biology, and shortly thereafter, began working for the Navy Marine Mammal Program, where I have been fortunate enough to work with an awesome group of California sea lions and bottlenose dolphins.

After graduation, I hope to explore the realm of business and marketing within the marine conservation community. There’s some incredible research being done, and I would like to help bridge the gap between the science and the public. It’s a steep learning curve, but my goal is to focus on market research and social media for Rising Tide – so please stay tuned to like the up-and-coming Facebook page, and follow us on Twitter and Instagram!

In my time away from studies, I enjoy continuing to work for the Navy Marine Mammal Program, hitting the trails with our two horses, and working my way down an ever-increasing list of must-reads.

I look forward to working with the Rising Tide Conservation team to help develop marketing material and getting the word out about Rising Tide’s incredible work. Rising Tide is accomplishing game-changing research, and I’m grateful for this amazing opportunity!

Huntley Penniman

As mentioned in our previous post, six adult melanurus wrasses (3 male, 3 female) were moved to the Tropical Aquaculture Lab back in February. After settling into their new environment and being offered a conditioning diet of LRS Reef Frenzy, PE mysis shrimp and Otohime EP1 pellets, the wrasses have quickly got back into their routine of spawning nearly every night. While we continue to work through some kinks in production, we wanted to share some of our excitement with our latest group of captive bred melanurus wrasses.

Video 1: Melanurus wrasse broodstock spawning at dusk. Notice in slow motion all three males can be seen making an attempt at fertilizing the female’s eggs.

Figure 1. 10 dph melanurus wrasse larva.

Figure 2. 14 dph melanurus wrasse larva.

Figure 3. 36 dph melanurus wrasse juveniles.

Video 2: Melanurus wrasse juveniles, 36dph.

The Rising Tide Team at the Tropical Aquaculture Laboratory

Rising Tide has caught up to the times and, thanks to Huntley, finally has a facebook page. We're only a week old so there's not a lot on there, but it'll fill up fast. It's a great way to keep up with all the things going on at Rising Tide facilities that may or may not make it on the blog. There will also be a link posted on the facebook page every time something is posted on the blog. Below is the link to the page, check it out and pass it on to your friends.

Facebook page: https://www.facebook.com/pages/Rising-Tide-Conservation/850675348332972

It’s been about a year since we reported our best success to date with rearing yellow tang, having gotten larvae through to day 83. Since then we’ve had some repeated successes getting the larvae past the first month or so, but never any quite as far along as that cohort from last January. Frustratingly, we seem to have taken a few steps backward again (as seems more common in this field than not), and are now struggling to keep the larvae going past the first week. We have been revisiting the protocols used from that successful period to ask a lot of questions pertaining to why that worked then, and not now.

Yellow Tang larvae reared at OI. A=14 dph, B=24 dph, C=36 dph,
D=45 dph, E=50 dph, F=60 dph. Scale bar = 1mm

Hawaii Pacific University Graduate Students (left to right) Aurora Burgess,

Emma Forbes & Erin Pereira-Davison

I have a great group of ambitious graduate students working on some key aspects of this challenge. Emma Forbes is focusing her research on the microbial community associated with the live feeds and rearing environment, which may have huge effects on larval survival. Erin Pereira-Davison is investigating several key environmental parameters that could affect first feeding success. She’s looking at the effects of photoperiod, light intensity, turbidity and prey density on first feeding in the larvae. Aurora Burgess will be focusing on the development of the feeding mechanisms in the early larvae, and how this development impacts prey selectivity and feeding ability. She will also be looking at alternative prey items from the wild, compared to our cultured copepods, and testing their use in the culture process. On top of all this, we have also recruited new broodstock from partner institutions in Hawaii and have recently obtained good spawns from these new stocks. This will help us determine if perhaps our recent challenges are egg quality-related.

All of these projects working together will hopefully reveal some important insights into the culture processes that will help us better understand the unique requirements of these larvae. Stay tuned for updates from our work, and hopefully some more success to report soon!

~Aloha,

The Rising Tide crew at the Oceanic Institute

As a student at Hawaii Pacific University I am fortunate enough to complete my Masters in Marine Science while enjoying the gorgeous Hawaiian sunshine. I am originally from New York and graduated from Old Dominion University in 2012 with a Bachelor of Science in Biology. After graduation I took an internship at the Two Oceans Aquarium in Cape Town, South Africa. It was there that my interest in marine ornamental aquaculture was sparked.

My research here is on the assessment of the bacterial community in our live feeds (copepod nauplii) with the addition of probiotics. I am using varying next generation sequencing techniques to assess bacterial communities in the nauplii and potential shifts in bacterial communities with the addition of the probiotics. With this information we are hoping to gain some insight into the bacterial composition of the larval gut and increase larval survival past the first 9 days.

After graduation I am hoping to continue research at OI, because you can’t really go wrong with fish and Hawaii! With luck they’ll let me stick around and I can continue some genomic work with our broodstock and larvae to further advance our understanding of the yellow tang life cycle.

When I am not hugging all of my fish, I can usually be found playing in the ocean. I am an open water swimmer and enjoy getting in the water every chance I can! Last spring we swam 13.2 miles between the islands of Maui and Lanai and are hoping to try again this spring! My biggest focus currently is wrapping up my thesis and enjoying the ocean as much as possible before the “Hawaiian winter” sets in!

I am a second year graduate student with a graduation date of May 2016. I am currently working with first feeding larval yellow tang primarily during the crucial, first feeding bottleneck. My project deals with different parameters of the rearing environment in hopes of improving feed incidence, growth and survival. My thesis is officially titled

"Effects of Photoperiod, Light Intensity, Turbidity, and Prey Density on Feed Incidence, Growth and Survival in Cultured Larval Yellow Tang *(Zebrasoma flavescens)*."

To date, I have been able to determine an ideal photoperiod as it pertains to feed incidence which OI has applied to the current groups of 20 day post hatch (DPH)+ yellow tang larvae. Light intensity and turbidity have also yielded significant results that may be applied to larval rearing in the future.

Trials pertaining to prey density are ongoing. Once completed, I will run an experiment where all the new found parameters will be combined and compared against OI’s previous rearing parameters in hopes of finding significant improvements in overall survival during first feeding (3-5 DPH)

Recently my preliminary photoperiod data was accepted for exhibition at the World Aquaculture Society’s conference in Las Vegas, February 2016. Presenting my research is a great opportunity to share the unique research going on at OI with the help of Rising Tide conservation.

On a personal note, I am a Florida native where I completed my undergraduate degree at the University of West Florida under the guidance of Dr. Alexis Janosik and Dr. Toby Daly-Engel. After graduate school I plan on spending some time in the aquaculture industry and then pursue a PhD pertaining to aquaculture, specifically ornamental aquaculture if possible. My husband Ryan Davison is active duty Army and we have two fur babies named Jasper and Icarus.

Colurella adriatica update

Something A Little Different...

One small step….Pacific Blue tang update

Emma Forbes update: Understanding Bacteria at OI

Rising Tide expands in Florida

Golden Trevally

Rising Tide Intern Joe Frith

Rising Tide at MACNA 2014

Matthew DiMaggio joins TAL; PhD Posting

Larval Rearing of the Purple Masked Angelfish (Paracentropyge venusta) Using Only Cultured Food

UF / IRREC's New Graduate Students

Commercially Available Porkfish

Early Success with a Halichoeres Wrasse!

Pomacanthus Angelfish Update

Huntley Penniman Joins Rising Tide

Breaking The Internet: Check Out Our Wrasses! (safe for work)

Rising Tide Has A Facebook Page!!!

Update on Yellow Tang Research at OI

Callan Lab at OI Grad Students: Emma Forbes

Callan Lab at OI Grad Students: Erin Pereira-Davison