Coral Spawning 2019

After conducting coral spawning experiments since 2013 in wet-labs – a total of 13 coral spawning events – I finally had the opportunity to see it for the first time in the wild. The chance of seeing spawning was uncertain, as water temperatures for the time of year were unseasonably low, and we had heard very few corals had developed pigmented eggs. Still, Magnetic Island corals had spawned without fail in October since I can remember, and so we decided that at worst we would get a few nice days holiday. There wasn’t much to lose.

The first night was really a night designated to test equipment and find a good site, but within a few minutes of decent, we saw the first setting corals. The first coral I observed spawning was at ~8 pm, and various Acropora and Montipora spp. spawned past our ascent time of 9:30pm. There was lots still set as we exited the water.

Note: I haven’t done any editing on the photos so I can keep a reference of how things looked underwater just in case I want to work on some of these spp. in the future. All photos taken with a dive-torch and a TG-6.

PA170207
The first coral I saw setting around 8pm.

PA170209

PA170214
I find this one interesting. The branches have almost no egg-sperm bundles, but are super-dense between the branches.

PA170220PA170225

PA170237

PA170240

PA170255

PA170263

PA170268

PA170280

PA170287

PA170319PA170323

PA170328
The coral-eating Drupella snail

PA170295

PA170341

PA180360
The zooplankton attracted to the light were nuts. …and had a good sting.

PA180362

On the second night there was, suprisingly, no spawning. It still made for a fun night-dive but there was hardly the flurry of activity from the previous night. The plankton, crabs, sharks and fish had mostly disappeared, worn out from the night before.

PA180364

PA180366

PA180379

PA180390
This blenny apparently likes to sleep above the waterline. 

PA180386

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s