Coral Made from Frozen Sperm in Australia

Our fourth year of field work at the Australian Institute of Marine Science (AIMS) is winding down. The season was long this year with a split spawn, meaning that the 1st full moon of the Australian summer was very early in November, so the lunar signal that the coral use to time their normally once-yearly spawn was not really clear, so some coral spawned with that 1st full moon and some spawned with the second full moon of the summer in early December. We took a full crew including Dr. Mary Hagedorn, head of Reef Recovery as well as her assistant Ginnie Carter, aquarist Mike Henley and Taronga Conservation Society’s reproductive biologist Rebecca Hobbs for the November spawning event. During that time, we were able to a new species to our frozen bank at Taronga’s Western Plains zoo as well as increase the samples and genetic diversity of 4 other species, bringing our count for Australian species to 7 and our species count worldwide to 11.


Sperm samples being frozen. Photo by V. Carter.

Moving forward from banking material, this year, we made coral larvae from fresh eggs with sperm samples that had been previously frozen, proving the concept of the future uses of our frozen banks. Mike Henley stayed at AIMS through the beginning of December to care for the coral larvae we created as they settled onto tiles in tanks at AIMS. This is a critical period of the coral life cycle in which the coral larvae has to go from swimming about to finding a good place to start laying down their skeleton and growing into what most people think of when they think of a coral, basically, this is the time when they find their permanent home and start to grow. With Mike staying to care for our larvae, he also had the chance to add to their numbers by being at AIMS for the second spawn of the split spawn and creating even more coral larvae from fresh eggs and frozen sperm. Mike will remain at AIMS until December 21st, and then it is our hope that working with AIMS scientists, we can grow some of these coral to maturity.


Mike Henley examining tiles to count settled coral. Photo by R. Hobbs.


Settled juvenile coral that was created using frozen sperm. Photo by M. Henley.

In addition, Rebecca Hobbs worked to create coral embryos from single coral cells. By breaking embryos apart at either the 4 or 8 cell stage of development, each cell that was created is theoretically able to grown into all the cells of a coral, i.e. they are stem cells. Rebecca was able to do this, and from her single cells, she had coral larvae grown, survive and settle. This is important for our work as well, since freezing single coral cells would allow coral to be grown from these cells in the future without the added step of fertilization and need for fresh eggs.


A settled coral grown from a single cell created at the 4-cell stage of embryo development. Photo by M. Henley.

All in all, our fourth year of work in Australia for the Great Barrier Reef spawning event was a great success. We are so happy to add another species to our bank and increase it’s robustness with our other species. We are also so pleased to see our bank working with our settled larvae this year.

AIMS Spawning Success – Australia’s Frozen Bank Continues to Grow

The Reef Recovery team has come together for a second year of spawning for corals from the Great Barrier Reef. Our researchers from the Smithsonian Institution, Taronga Conservation Society and Monash University have joined forces once again with scientists at the Australian Institute of Marine Science (AIMS) to continue building Australia’s frozen coral bank. AIMS researchers brought several coral species in from the Great Barrier Reef and so far 4 species have spawned, with sperm from two species being added to the bank, along with embryonic cells from one species. We will continue to watch for spawning for the next several nights, as each species spawns at it’s own specific time of the evening, over the course of several days.



Montipora digitata spawning in a tank at AIMS. In the center, you can see one egg/sperm bundle just barely released from a polyp at the center of the photo and one bundle rising through the water column in the upper-right side of the photo. Photo by M. Henley.



AIMS researchers, Dr. Emily Howells and Dr. David Abrego prepping to make coral larvae from freshly spawned eggs and sperm that was frozen last year. Photo by M. Henley.

The New York Times Covers Our Frozen Coral

Check out the Science section of the New York Times today:

Frozen Sperm Offer a Lifeline for Coral


BLIZZARD A colony of elkhorn coral, Acropora palmata, spawning in Belize. Coral spawns are poorly understood; many are tied to phases of the moon. Photo by R. Ritson-Williams.


The author, Michelle Nijhuis came out to Hawaii to visit us during spawning last year and then joined us for our crazy trip to Belize. Many thanks to her for writing this story and getting it into the New York Times!

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We’ll post pictures from the lab and field with updates on our research and what we’ve been up to. This is a great way to keep in touch and be up to date with all we do.


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Australia’s Frozen Reef Continue’s to Draw Media Attention

Media coverage of Australia’s frozen coral bank, which was started by the Reef Recovery team last November, continues:

Great Barrier Reef survival frozen in Outback – ABC Radio Australia


Great Barrier Reef hopes on ice in Aussie Outback – My Sinchew

Creation of Australia’s First Frozen Coral Bank

In late November, a few members of the Reef Recovery team met up in Townsville, Australia at the Australian Institute of Marine Science (AIMS) to begin the creation of a frozen repository for Great Barrier Reef Corals. Dr. Mary Hagedorn and myself, Ginnie Carter, traveled from Hawaii, Mike Henley came from Washington, DC and Dr. Rebecca Spindler came from the Toronga Zoo. AIMS researcher, Dr. Madeleine van Oppen was our gracious host along with many other researchers there.


Acropora tenuis spawns in a tank at AIMS. Photo by M. Henley.

We were able to work on two different species of corals that were brought into the lab and spawned. Australia’s first frozen coral repository was created as we were able to freeze sperm from Acropora tenuis and larval cells from Acropora tenuis and Acropora millepora.


As Acropora tenuis spawns around 9:00pm, Dr. Mary Hagedorn and Ginnie Carter work into the night, cleaning the eggs and sperm for fertilization experiments. Photo by M. Henley.

Press in Australia and around the world took notice of this landmark achievement. You can follow the links below for more on our work at AIMS.


BBC – Great Barrier Reef particles frozen

ABC News – Scientists look to cryogenics to preserve Barrier Reef

The Sydney Morning Herald – Piece of Great Barrier Reef put on ice in frozen zoo




Dr. Rebecca Spindler of the Toronga Zoo shows off a dry shipper full of frozen coral samples that mark the creation of Australia’s first frozen coral repository for the Great Barrier Reef. Photo by M. Hagedorn.

SECORE Adventures in Belize

The Reef Recovery Team has just returned from a field trip to Belize to work on the endangered corals Acropora cervicornis, Staghorn coral and Acropora palmata, Elkhorn Coral.

Our trip was full of drama, but also full of great people and lots of adventure. You can read about our trip here:


SECORE Blog


Rice Coral Spawning Success

After such disappointment with the Mushroom coral spawn, the Reef Recovery team was happy last weekend when by the non-light of the new moon, Montipora capitata, or rice coral spawned successfully.


A colony of Rice Coral, Montipora Capitata just off the dock at Coconut Island in Kaneohe Bay, Hawaii. Photo by L. Grassman.

We were able to spawn these corals in floating pots in our outdoor tanks here on Coconut Island. The corals in the water around the island spawned heavily as well, so we collected egg/sperm bundles from both locations and were able to conduct our experiments.

Rice coral, like many corals around the world, release bundles of eggs and sperm packaged together. These bundles float up to the surface of the ocean where they break apart. They then have to find eggs or sperm from another colony, as they do not self-fertilize. For our work, this makes an added challenge as we have to break bundles apart ourselves to collect the sperm that is inside. If the bundles break too early, the sperm we need may end up too dilute for cryopreservation. Each step of our process has to be done at the right time and in a very particular manner to ensure that we are able to cryopreserve enough sperm. These rice coral here in Hawaii provide us with a unique opportunity to work out techniques like these before we head off to places like Belize, where we will be going in August, to work on endangered species there with similar egg/sperm bundle spawning strategies.

Check Out Our Work With SECORE

For the past several years, we have collaborated with SECORE to conduct coral reproduction workshops at spawning sites around the globe. These workshops have trained aquarists from zoos and aquaria around the world on how to raise coral larvae from larvae to adult corals. These workshops were also an opportunity for the aquarists, as well as community volunteers at the spawning sites to see the type of research that is going on to save corals, by seeing our cryopreservation work, as well as the work of other coral scientists collaborating with the SECORE group.

You can check out the weblogs of these workshops by clicking the link below:

SECORE Weblogs

There are links for several SECORE workshops that occurred in 2010, as well as a drop-down menu for workshops from 2005-2009.

Watch the SECORE website for information about workshops this year.

Mushroom Coral Love Was Not In the Air

With our crew assembled and colleagues visiting from Washington State, we patiently waited last Friday for our Fungia to spawn.

Close-up of Mushroom Coral Displaying Green Florescent Protein in its Tentacles - Photo by V. Carter



Fungia scutaria, or mushroom coral have been kept in water tables out here at the Hawaii Institute of Marine Biology for many many years. Several research groups here work on them, and they usually spawn like clockwork a couple days after the full moon around 6pm for a few nights from May through September.

This month, however, their spawning was quite poor. We only saw light spawning from several males and just 3 females on one night. Other groups on the island reported no spawning at all from their mushroom corals. This was very disappointing for us, as well as for our visiting colleagues.

Many factors could have resulted in the lack of spawning, but we cannot say for certain what caused this. We have been having an unusually cool and rainy summer here in Hawaii which may have contributed, but there is no way to know for sure. Other factors from more global impacts may play a role as well.

As spawning of corals may be coming less predictable, the need for live and frozen banks of coral genetic material grows more pressing. While mushroom coral here in Hawaii will have several more times this summer to attempt to spawn, many species around the world only spawn once per year. Last year, a trip we had scheduled to bank two endangered coral species in Belize was canceled because rising ocean temperatures caused the corals to spawn a month early resulting in our trip being scheduled a month too late. As corals become more threatened around the world, we can only expect to see more non-typical, or even non-existent spawning events.

As for our mushroom corals here, we’ll keep our fingers crossed for their July spawn.

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