Some good news on the environment

[Allan Carr]

A giant pristine coralreef has been discovered off Tahiti


https://www.bbc.co.uk/news/science-environment-60047368

[Divemouse]

Who knew the 'twighlight zone' started at 30m?

[John63]

Nice pic of the photographer kneeling on the reef…

[Ian@1904]

Is the reef supposed to have fish swimming around? I could not see any fish.

[jturner]

Is the reef supposed to have fish swimming around? I could not see any fish.

There's a reef a bit like that off Banda Neira in Indonesia, where the coral has grown on an old lava flow from the 80s. The coral is spectacular and has grown incredibly fast but there's not many fish around. I suspect (though I'm no marine biologist so might be talking lobbox), that in both cases, whilst the coral is very nice, the reef system isn't (yet) in proper balance for some reason or other; you have loads and loads of coral polyps, which is good for those fish that eat them but if you happen to be an algae feeding fish, a sand/rubble snuffler or prefer to stay shallow to eat your coral, you're out of luck. That kind of coral doesn't make a great hiding place for very small/juvenile fish either, so it's not a great nursery, especially down so deep. I guess it also depends on where it is in relation to other reef systems - the Banda Neira reef is within a few hundred metres of other "normal" healthy reefs but the fish don't seem to be all that bothered about moving in (except for a few big parrotfish, a few small groups of sleepy snappers/grunts and the odd trigger).

[Allan Carr]

THe reefs around Rarotonga in the Cook Islands were a bit like that when we dived them - beautiful coral but not many fish.