Corals Can Reestablish Symbiosis After Bleaching

[Len]

http://www.sciencedaily.com/releases/20 ... 032852.htm

ScienceDaily (June 8, 2004) — BUFFALO, N.Y. -- Corals can develop new symbiotic relationships with algae from their environments after they've undergone bleaching, the process by which corals whiten as a result of environmental stress, University at Buffalo biologists report in the current issue of Science.

 

[Anonymous]

Pshhh Len don't steal Shane's thunder

 

[Anonymous]

8)

 

[Anonymous]

But I wonder how regularly it happens. I'm guessing the next stage is working out how to help the process.

 

[Anonymous]

The process can't be helped if the mechanism is not understood, though.

It has not been clear whether recovery resulted from the few remaining symbiotic algae, or algal symbionts, remaining within the coral tissue since early development, or if coral could acquire entirely new ones from their aquatic environments.

I'm curious as to the choice of coral as well, and whether or not this might be observed in other photosynthetic hermatypic corals.

If corals could be inoculated with their appropriate symbionts, then it seems there may be a way for humans to have a direct hand in undoing bleaching.

 

[blackcloudmedia]

Ive witnessed this in my tank before. I purchased a monti digi that bleached due to irritation. I gave up on it and put it near a red monti cap, about a month later the digi was red. When I sold my sps the LFS was stoked to see a red monti digi and asked where I got it. I told him I had connections 8)

 

[Anonymous]

The process can't be helped if the mechanism is not understood, though.

It has not been clear whether recovery resulted from the few remaining symbiotic algae, or algal symbionts, remaining within the coral tissue since early development, or if coral could acquire entirely new ones from their aquatic environments.

I'm curious as to the choice of coral as well, and whether or not this might be observed in other photosynthetic hermatypic corals.

If corals could be inoculated with their appropriate symbionts, then it seems there may be a way for humans to have a direct hand in undoing bleaching.

You're right. I was kind of binding that whole "understanding how they whole process thing works" with my how to help it happen point. Lazy drafting, sorry.

 

[Anonymous]

Tom, ultimately the article seems a wee bit contradictory, because I quoted that paragraph, but further down they say that they essentially did inoculate the corals. I suppose the remaining question is whether or not these corals would have regained density in absence of the 'inoculation' (I think they say they 'exposed the corals' to symbionts).

Ive witnessed this in my tank before. I purchased a monti digi that bleached due to irritation. I gave up on it and put it near a red monti cap, about a month later the digi was red. When I sold my sps the LFS was stoked to see a red monti digi and asked where I got it. I told him I had connections 8)

Seriously? :lol: That just earned you a Sump CookieTM.

 

[Ben1]

Ive witnessed this in my tank before. I purchased a monti digi that bleached due to irritation. I gave up on it and put it near a red monti cap, about a month later the digi was red. When I sold my sps the LFS was stoked to see a red monti digi and asked where I got it. I told him I had connections

From what I have read, zooxanthellea doesnt produce pigments. The pigments are producded by the coral itself and the zooxanthella is just brown, this is why IIRC in ULNS corals get brighter and more pastel, becuase the zoox are less dense and tanks with high nutrients levels have brown SPS.

 

[Ben1]

"We found cell densities within the coral had increased between nine and 31 times the level measured immediately following the bleaching episode," said Lewis.

During the six weeks following 'bleaching,' the corals were exposed to algal symbionts that were added to the aquarium water.

I am no expert but how does this show the corals actually re-established anything, in paticular the zoox they added to the aquarium water vs. just a fast rebound of the 1% zoox densisity that was left in the coral to begin with. I am probably missing it but if the subjects had light on them again during this following 6 weeks how did they determine the zoox was actually being absrobed at all? I know I have had coral rebound from bleaching but I always assumed it was just repopulating the zoox from w/e little zoox was still in the tissue itself.

 

[blackcloudmedia]

Hmm its an interesting study I hope they go much further in depth as Ive only had a sample population of 1 to go by in my tank lol. I dont know whether the pigment comes from the coral or the zooanthelae but I do know that my monti went from purple/blue to white to red-whilst it was in close proximity to a red monti cap. Come on Marine Biologists get to the lab :lol: :wink:

 

[Anonymous]

All they're saying is that this coral can rebuild densities of zooxanthellae. They are not claiming to know by what mechanism, only that they forced a serious reduction in symbiont density, and observed a subsequent increase in density when the coral was placed into more favorable conditions. Conditions that included, apparently, exposure to symbionts in the water column.

I am less concerned with the mechanism than with the event itself, and even more so with how it might be extrapolated to hermatypic corals.