Jamie Craggs’ Game Changing Work at the Horniman Museum

Jamie Craggs’ Game Changing Work at the Horniman Museum

Over the years I have witnessed a lot of breakthroughs in the hobby. In terms of propagating corals we have gone from barely being able to keep most corals alive to the point where we can now propagate most corals through some form of fragmentation. Some of these advancements we have achieved have allowed for some damaged reefs to be repopulated by corals that have been “grown out” away from the ocean. In this regard, we should take pride in what we have been able to accomplish and how if climate change is rectified we may feel some pride that some of what we learned can at least in a small way help to repopulate these damaged reefs.


A photo catching one of the first captive spawns in Jamie's tanks.

However, despite all of these advancements, one holy grail has for the most part eluded the hobby and public aquariums and the scientific community as well: getting sps corals to spawn in a captive environment. Despite all of the advancements that have been made, few of us have had mass spawnings of sps corals occur in our tanks. Sure some of us have had clams, or snails or urchins and there have even been reports of individual soft corals spawning, but up until recently only a few have been able to crack the secret code to get sps corals to spawn in a closed mesocosm. And in most instances this was more or less a random event.


A montage of some of the factors Jamie has examined that produce a successful spawning event.

However, this changed last November when Jamie Craggs of the Horniman Museum and Gardens in London succeeded in getting four different genera of sps corals to spawn at least one year after fragments had been taken from the wild. Some of Jamie’s work has been presented at MACNA and ReefStock, but the full explanation of what he did to accomplish this feat had not been fully revealed until he published his work in Ecology and Evolution

I met Jamie at MACNA three years ago when he spoke and was lucky enough to get the opportunity to visit him at the Horniman Museum in 2016 and see his work that at that time he was just getting started. Having seen Jamie’s talk and learning what advancements he was making, I was delighted when David Saxby suggested we spend a day with Jamie and learn first-hand what he was working on.

Screen Shot 2018-04-05 at 10.03.45 PM.png

The press is also finally starting to take notice of Jamie's work.

For those of you unfamiliar with the Horniman Museum, it is one of the oldest natural history museums in England and has been in operation since Victorian times. It is the result of it’s founder Frederick Horniman collecting artifacts of natural history and offering visitors to his home the opportunity to see them, these exhibits eventually became a museum named after him. From an aquarist’s point of view it is especially interesting as it still houses anemones that were some of the first invertebrates kept on record, they are preserved of course. Phillip Henry Gosse discussed these anemones in his book published in the 1850’s, however this museum is not just for housing old natural artifacts, but has shown an interest in marine life since it’s inception.


Some of the "newer" corals spawning in his mesocosms.

So considering that it had such an auspicious start, there is little wonder that it is now at the forefront of coral reproduction and with it potentially helping to preserve natural reefs. In this regard, Jamie has been interested in coral reproduction since he started there over 12 years ago, and like many of us has learned that success and progress in understanding sps corals and their many secrets takes time. Even before he started working there he kept abreast of advancements in the hobby and has used much of this knowledge to help make this major advancement even faster than would have happened had he started from scratch. During his work and research Jamie has found a lot of things that are relevant to us hobbyists and that down the line may help us significantly. In this regard I strongly suggest that everyone read his paper to add to their own knowledge base of what is required for “successful” coral husbandry. I say that, as from my own perspective I learned more from talking with Jamie and his writings than I have learned in a long time.


A shot of Jamie's "chimera" coral after it is successfully growing out.

In talking with him one of the first things he told us was that while many of us now provide conditions adequate for maintaining healthy corals and even having them grow, getting them to the point where they have enough energy for gamete production requires far more than providing them leftover food and fish poop.

Another important finding that Jamie provided and that will hopefully add to our success, is that there is a lot more variability in the water chemistry in different areas of the ocean and that parameters may change seasonally as well as on different locations on the reef itself. That is, salinity, temperature, nitrate, phosphate, alkalinity and calcium values to name a few, are different if you are in Australia on the Great Barrier Reef, in Fiji or in Indonesia and these values will vary some if it is winter versus summer or on a reef crest versus in a lagoon. However, the variability over short periods like days or weeks is relatively low. Jamie was meticulous in obtaining these water samples and testing them and tried to limit the potential for testing error by having all of the water samples he retrieved sent for ICP testing. By doing this he felt it more likely that any differences would only be the results of differences in the water itself, rather than in the testing procedure.


Some of spawn of an event successfully collected.

These specific water conditions were maintained even once the corals were in his closed mesocosms, so that corals when from Singapore or Australia were being grown out and conditioned for spawning, the water conditions they were in would be similar to where they came from. In similar fashion, the lighting and tank temperatures used to condition the corals was programmed to match the day and night cycles both daily and on a yearly basis so that they would closely mimic the conditions required to induce spawning. That is, from what we saw the daylight and lunar cycles on the corals tanks were exactly the same as in their natural habitats. Blackout blinds were also used on these tanks to prevent stray light from infiltrating into these tanks and corrupting these cycles. Since the reefs from which these corals were taken are 8-10 hours ahead of the time in England, if the light cycle in England were used it could have thrown things off.


An earlier photo of the chimera tenuis.

While lighting and the appropriate lunar cycle have been found to be critical to induce a spawning event, providing proper coral nutrition has proven to be just as critical in order for eggs and sperm to be produced. From his paper and from speaking to him, it is clear that the corals are fed significantly more often and fed specifically in a better way than any reef owner I know is currently doing. The corals are not only a fed variety of foods, including live, frozen and processed but they are also fed a variety of sizes so that the corals will find something that they can consume to provide proper nutrition. Due to the potential for this feeding schedule to cause problems such as algae blooms or nutrient build up, the tanks employ advanced means of filtration and nutrient removal once feeding has occurred. Feeding corals and the necessity for doing so has been a topic of debate in the hobby for a long time. However, after discussing this aspect of coral husbandry with Jamie, seeing his results as well as doing additional reading, it is clear that many of us, myself included, are missing the boat by not feeding our corals either enough or a wide enough variety to provide proper nutrition. The typical thought process that strong light and fish poop are more than adequate for our corals health was quickly abandoned once I saw Jamie’s corals. While light and fish waste may be adequate to provide most of the coral’s energy needs, from what I saw there it is clear that it does not provide enough nutritionally to allow for the corals to reproduce. Obviously reproduction requires a lot of energy and if we are not providing it, the corals may grow and look healthy, but most will not be meeting their energy needs for gamete production.


One of Jamie's corals with its branches full of eggs.

While getting sps corals to spawn away from their natural environment is exciting, it is just the beginning. Now that he has accomplished this Jamie is working on getting corals to spawn more frequently than once a year. His goal in fact is to induce monthly spawning events. And once he accomplishes this on a consistent basis he hopes to determine exactly which variables are most critical. Once he achieves this and publishes it, it soon may be possible for many of us to have coral spawning events occur in our own tanks on a regular basis. I’m not sure what this will mean or even if our tanks will be able to handle it, but considering how long it has taken us to get here it is at the very least incredibly exciting.


Some of the first corals that were grown out and spawned by Jamie.

And this is just the start, just as importantly, Jamie is working on determining what factors lead to proper settlement of the planula and to maximize their survival and growth as well as why some genera of corals reach a 100% rate successful spawning while others fall far short. Because he now has literally thousands of planula to work with Jamie is working on other things such as combining planula early in their growth showing different colors and watching them grow out. And he is taking this one step further and trying to find the morphs that are more heat tolerant than others. The goal of this is that is the ocean temperature continues to rise hopefully he can find and select for morphs that can tolerate the warmer temperatures. In fact, this research is no longer limited to just England as Jamie is also now working in Florida to research this here with Atlantic and Caribbean corals.


Jamie working in the mesocosm.

The work that Jamie and his colleagues are doing is remarkable and may impact the reefs around the globe for decades, and the information his work is providing to the hobby will further enhance the success we are now already achieving. This research may not only help us better understand what happens during a spawning event, but also may help us better understand the conditions necessary to achieve it in our own reefs as well as to maximize its success in the wild. If conditions continue to deteriorate in the wild, the corals we have in our tanks may act as a bank of sorts and may be a viable way to repopulate the reef on a much larger scale than we are doing now once conditions improve. After major bleaching events in the Maldives, Fiji and the Great Barrier Reef, it is known that it takes a minimum of 7-10 years for a reef to even get close to its old vitality. And with back to back bleaching events occurring on the Great Barrier Reef the last two years it may take significantly longer if these bleaching events occur more regularly. Understanding and using some of the information that Jamie is developing in his spawning experiments in closed mesocosms may allow us to be able to repopulate a damaged reef much quickly and expeditiously than we can currently do with fragmented corals. In this regard, Project Coral, which is the name of Jamie’s research project, may be an important first step in helping to maintain the health of coral reefs around the world.


A tank full of spawn that have settled and are growing successfully.


A poster of Project Coral.

When we walked into the Horniman Museum and saw the stuffed birds and the overstuffed walrus I thought that this was a typical old museum and it was highly unlikely that a spoiled reefer like me would learn anything new. Little did I know that some of the most cutting edge research in coral reproduction was being done in such a place. Further evidence that there is still much for me and us to learn. I do not tell people where to spend their money, but if you are looking for a worthwhile research project to contribute too, this one should be at the top of your list. You will see the level of commitment Jamie has to this project and his meticulous attention to detail if you read his paper.

Screen Shot 2018-04-09 at 7.51.35 PM.png

The first page of Jamie's paper outlining his successful spawning project.
About author
Mike Paletta
Michael Paletta’s actual career is working in genomics in breast and colon cancer for Genomic Health. He has been an avid reef keeper since 1984. He has kept personal reef aquaria ranging in size from 20 gallons to 1200 gallons and has helped set and build other reef aquaria up to 4,000 gallons in size. He currently maintains several reef aquaria including a 300 gallon sps dominated tank and a 75 lps tank. He has also consulted for The National Aquarium in Baltimore as well the Pittsburgh Zoo and Aquarium.

Michael has published over 100 articles on various aspects of reef keeping in SeaScope, Aquarium Fish Magazine, FAMA, Practical Fishkeeping, and Coral Magazine. He has also published two books: The New Marine Aquarium and Ultimate Reefs. Michael has been invited to speak at various venues around the world and across the country and has given over 200 such talks.

Article information

Mike Paletta
Last update
4.55 star(s) 11 ratings

More in General Saltwater Aquarium

More from Mike Paletta