I’ve been learning how broadcast spawning coral looks like tropical snowflakes. Snowflakes because they are small pinkish-coloured balls. These balls of sperm and egg rise to the surface of the water. In this way they are upside-down to snowflakes. They rise instead of fall.
Once at the surface, these bundles unfurl into free-swimming gametes. The eggs and sperm meet with the sperm and eggs of other corals. Coral sperm burrows its way into coral eggs. This is the reason corals have been building up the energy for their once-a-year orgy. Fresh blood – so to speak. Even though corals don’t really have blood.
We’d been underwater for 45 minutes already. Lars said the broadcast spawn was likely to go off at 9:30pm. Give or take a few minutes, he said. I looked at my very lovely new dive computer. It read 9:45pm. Hmm.
Lars had sent us to the southern out-planting site at Buddy’s reef. This was the smaller, more compact site. He’d headed to the more expansive northern site. We’d been there the night before, but he wanted eyes on lots of sites tonight.
The staghorns were in variable shape here. Spiky and interwoven, growing upwards and out. Some were definitely healthier than others. It reminded me of bushes where the top layer of the plant is still alive and growing but the layer underneath not so much.
Jack was busy closely leading Delph around. It was Delph’s first night dive. They went alongside the staghorn. He was shining the UV torch on different things.
Lu and I stayed on top of the staghorns. Their polyps were out of their cups, extending their tentacles to find passing food. It was hard therefore to make out their balls of gametes. Lu and I looked – and for some it seemed the bundles were being prepared for release.
When will you release your prize?
‘Soon,’ the coral seemed to reply, ‘not yet though.’
And that was it. We dived and we dived. Jack lead Delphine around by the crook of her arm. She appeared to be having a super time. I watched them in the distance like a slow night train.
Lu and I kept ourselves busy by catching fireworms. Lars had given us a jar and a pair of forceps. Our job was to clear the fireworm. The fireworm eat the coral. We picked them up with the forceps and quickly moved them into the jar. Careful because the fireworm drop their ‘bristles’ which hang white in the water and sting on contact.
Lu loved this job. She used the forceps while I quickly opened and closed the jar. We had a dozen in no time. Only one small sting. Eventually, Jack motioned back to Edna. It was the end of the dive.
Lars’ party was also emerging when we came up.
‘Did you see any spawning?’ we asked.
Lars and his party shook their heads.
Why didn’t the corals spawn as predicted?
Lars swam to the stairs, to make his way out. He seemed quite chirpy about it. ‘That’s nature,’ he said.