Alex Mustard - The Great Spawn


For 364 days of the year, corals do a very good impression of a rock. But on one magical night they explode into effervescent life.

Most species of reef corals spawn synchronously in a massive release of gametes that gives the best chance of successful fertilization and overwhelms any potential predators on their eggs. But for the photographer this offers a tiny window to have your camera pointed at the right place at the right time. The star coral in this photo releases all its gamete bundles (the tiny balls of eggs and sperm) in about 10 seconds. That is ten seconds in a whole year. Oh and it happens late, late at night. Underwater, obviously.

Fortunately the event is predictable, to a degree. Success depends on your ability to decipher the combination of the annual cycle of temperature, the (lunar) monthly cycle of tides and the daily cycles of light. You make your call and then jump in the water to time your night dive to overlap the spawn. Scuba air tanks don’t last forever, so there is always a gamble involved. But when you do get it all right, it is a thrilling spectacle to experience.

Location: Cayman Islands, Caribbean Sea.

Tags: Alex Mustard, boulder star coral, coral reef, coral spawning, Montastrea annularis, night, reproduction, underwater

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  1. Theo said:

    28/09/2012 09:05

    Wow Alex this is incredible! Never seen such a thing before, great story, great picture, congrats!

  2. Werner said:

    28/09/2012 10:28

    So impressive! At the first glance you think these are stars over a mountain landscape. Really great!

  3. Alex Mustard said:

    28/09/2012 11:11

    Actually I was going to comment on that too. As it is a good follow on from Inaki's photo from yesterday.

  4. Geir Ole said:

    28/09/2012 13:27

    Superb! :)

  5. Faith Denise Rossell said:

    28/09/2012 15:11

    thank you for capturing this demonstration of one of the miracles of life!

  6. Heike Odermatt said:

    28/09/2012 16:28

    Alex, it is the same I thought when I saw the preview. It looks like a milky way. It is really another world and a great picture!

  7. Richard said:

    28/09/2012 17:47

    Awesome shot, Alex! Was there a back light? I plan on being there with OF next year . . .

  8. João Petronilho said:

    28/09/2012 22:06

    A stunning photo! The nature surprises us all the time with moments like this. Congratulations on the effort and manage to reveal one of the many secrets that hide our seas!

  9. Fabian said:

    06/10/2012 20:17

    Wow, what a stunning photo. Looks like it's backlit - I would love to hear the story of how this was made. I expect there was a lot of preparation involved.

    Nature is so amazing. How do all the polyps know to spawn at the exact same time?

  10. Bent C said:

    18/11/2012 15:59

    Very skilled capture. The backlit works great on this exceptional picture.