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teevee
09/04/2003, 08:20 PM
Excellent article this month. I thoroughly enjoyed it.

Edgar VM
09/05/2003, 06:43 PM
Hi Ron

I also liked it, but there are some questions I would like to ask you

First

If its true that the Acropora and some other corals are more "weedy" I think some species of the more slower, long-lived , "more effective" competitors are almost out of the game by now right? (I mean at the edge of extinction)?

How long does it take for a community dominated by acropora to be displaced by the othe corals?

With every storm/hurricane etc we should be watching more and more "weedy" reefs right? Is this true? I mean are these the kind of reefs we have?

Is there any evidence that the "older" Acropora communities have a tendency to produce more allelophatic susbtances? Im asking this because if the corals that do so are "more effective" in competition, should this tendency be followed by those that are becoming "dominant"?

regards

Skipper
09/09/2003, 10:04 AM
Yo. Just a heads up that Ron has been out of town for a bit. He should be back within the next few days.

rshimek
09/09/2003, 10:54 AM
Originally posted by Edgar VM

Hi,

If its true that the Acropora and some other corals are more "weedy" I think some species of the more slower, long-lived , "more effective" competitors are almost out of the game by now right? (I mean at the edge of extinction)?

Generally the longer-lived species are in different habitats, they generally live in deeper water. The "weedy" Acropora are generally in shallower water.

How long does it take for a community dominated by acropora to be displaced by the othe corals?

It varies from what I have seen. I suspect if disturbances are minimal, this could occur over the span of several centuries. On some Pacific reef platforms there were (emphasis on the "were") shallower diverse communities dominated by slower growing corals. A number of Palauan reefs were like this. They have bleached (in 1998-1999) and died... Algal reefs now...

With every storm/hurricane etc we should be watching more and more "weedy" reefs right? Is this true? I mean are these the kind of reefs we have?

In many shallow reefs, it appears that the Acroporid "thickets" that develop are maintained by storms. Deeper water areas - from about 10m and deeper often seem to be dominated by other corals, with different - slower growing Acropora as well as other corals.

Is there any evidence that the "older" Acropora communities have a tendency to produce more allelophatic susbtances?

I think you should ask Eric B. this. He is more "up" on this literature than I am. I think the evidence for allelopathic materials is presently too sparse to address that question adequately.

Im asking this because if the corals that do so are "more effective" in competition, should this tendency be followed by those that are becoming "dominant"?

Quite possibly. This would be a good doctoral dissertation project.... :D

Edgar VM
09/09/2003, 12:16 PM
Hi Ron

Thanks for the answers :)

In regards your comment

Im asking this because if the corals that do so are "more effective" in competition, should this tendency be followed by those that are becoming "dominant"?

Quite possibly. This would be a good doctoral dissertation project....

Well, if you have funding... I always wanted to be a Marine Biologist :p

Regards

rshimek
09/09/2003, 01:01 PM
Originally posted by Edgar VM

Hi Edgar,

Well, if you have funding...

ROFL!!

Actually, I think there has been some good work that addresses some of these points done out of UC Davis, maybe from Geerat Vermeij's group.

I always wanted to be a Marine Biologist :p

Well.... First you have to take the obligatory vow of poverty.

:D

Edgar VM
09/09/2003, 01:20 PM
You mean again????:rolleyes:

I'm already a Biologist :worried2:

:lol: ....

Edgar VM
09/10/2003, 07:37 PM
Hi again

I forgot to ask you

have you seen Hughes et al paper in Science about the reefs??

What do you think?

rshimek
09/10/2003, 09:53 PM
Hi Edgar,

Haven't had a chance to see it yet... Been far to busy to go to the library for the last couple of months. Have heard a bit of hearsay about it, which indicates it sounds reasonable, but I really don't know.

:D

Edgar VM
09/10/2003, 10:25 PM
Hope you can take a look at it...and also that you have some free time :D

Regards

rshimek
09/11/2003, 04:22 AM
Hi Edgar,

I hope to do a library excursion within the next couple of weeks, and I will let you know what I think of it. I will post a note here.

:D

Edgar VM
09/11/2003, 01:44 PM
Ok, will be waiting :)

regards

yardboy
09/25/2003, 12:37 PM
While I found your article interesting concerning competition, and am a little embarassed hoping you never see how thick I've got the animals in my tank, I have to differ with the statement about the population densities of corals in the wild. I've been diving for the last few years in the Philippines, and the densities of corals on the reef faces and spur and groove formations is much higher than 1/ft. As a matter of fact, there is difficulty in even finding a place to put your finger to steady yourself to look a t anything.

rshimek
09/28/2003, 11:47 AM
Hi,

In Acropora thickets and other places with cloned corals, or in very disturbed areas, this is case. Cloned corals don't compete, and in disturbed areas, the competition hasn't reached its conclusion. However in most areas that have been quantitatively studied, stony corals over a few centimeters in diameter are spaced far enough apart to prevent active competition between them. This generally is a distance of 6 to 12 inches.

Boomer
10/07/2003, 11:33 PM
Ron

Nice piece, on one of my favorite groups, the Bryozoans