Another spectacular spawning night! - WS GUAM 2014
After carefully scooping the egg-sperm bundles off the water's surface, we started the lab work. The eggs were fertilized, rinsed and measurements were made. We counted almost 500,000 eggs, enough to fill our remaining five kreisels and some large tanks containing static seawater. Compared to the kreisels, these tanks only allow a lower concentration of embryos, but they provide for a low tech approach that can be used in remote areas with limited resources.
[Lab work]
The fertilization rate was estimated at 40%. A number that may sound not so high, but it will give us approximately 200,000 embryos to work with. The next days and nights, we will take tender care of these coral babies, to get them ready for settlement.
[Jamie Craggs]
As promised, we interviewed Jamie Craggs—aquarium curator at the Horniman Museum and Gardens. This is the second time Jamie has joined a SECORE workshop, first as a participant, now as an organizer. Time to ask him a few questions about his motivations for coral research and conservation work.
What about SECORE's work attracted you in the first place?
The complexity of coral reefs, the challenges of keeping corals in captivity, the interactions on the reef, that's what I'm passionate about. I've been working in the aquarium industry for 15 years, and I've tried to specialize in corals and keeping them. For the past 14 years, I've been attending a conference back in the UK about coral research. Year on year it's more depressing, sort of 'get out there and see coral reefs while you can'.
Obviously, the whole goal of SECORE is to try and reverse that trend in some way. Coming out here ties in with understanding both how to protect corals in nature and how to manage them in captivity. An important goal for the Horniman is to operate on an international level. This workshop provides a perfect opportunity to speak and work with my peers both in the scientific and the aquarium community.
You already shared some information about the 'Horniman Project Coral' you're working on. How does this project relate to the work SECORE is doing?
Broadcast spawning events in captivity are rare and often catch the onlooker by surprise. An initial goal for 'Project Coral' is to develop techniques so that we can predictably spawn coral in controlled conditions. Once this is been achieved, it will provide a platform to develop captive coral reproduction research. This will support SECORE's work—understanding the role of resilience of corals in a rapidly changing environment.
For instance we could put future climate models into lab conditions and see what it does to fecundity, fertilization rates, grow out rates and so on. We also may be able to support local communities and enable them to supply corals into the aquarium trade and create ecological goods and services in a sustainable way.
Can you share some of the first results?
Last year, 'Project Coral' managed to induce two spawnings, from Acropora valida and Acropora prostrata. That answered some of the questions we had, for instance we know now we can spawn coral predictably in captivity. But it also raised a lot of questions about the reasons behind that. We've put five basic principles in place to induce the spawning: colony size, heterotrophic feeding, annual temperature cycle, photo period, and the lunar cycle. Now we are going to look at the circadian rhythm as well. Eventually, we also hope to develop a methodology to predict spawning times of other species.
In the end, the purpose of 'Project Coral' is to develop viable coral reproductive research work in captivity, using information gained during fieldwork. This would then provide a new area of research which will feed back into field studies and more the efficient techniques of reef restoration.