Lifespan of corals

aninjaatemyshoe · #1 12/30/2007, 12:59 AM

I'm not sure how many other people have thought much on this, but does anyone know how long corals actually live? Are they "immortal" like sponges, or do they reach senescence and die?

mfp1016 · #2 12/30/2007, 02:17 AM

I'm pretty sure most will just keep growing and growing under perfect conditions. But even in the wild something can and will statistically happen. I know that there are several large Porites corals off the GBR that are thought to be well over 800 to 1000 years old. Just an example, I'm sure someone will chime in.

IPT · #3 12/30/2007, 02:26 AM

I guess it depends on the specices. I'm sure some of the big cloanies live forever in a sense. As it builds probably some of the lower polyps die but the higher newer polyps are probably thriving with new ones budding all the time. Without disease or catastrophy I see no reason they couldn't "grow" for ever.

MCsaxmaster · #4 12/30/2007, 04:20 AM

Some appear to be theoretically immortal. Some appear to senesce and supposedly the genes for senescense have been found in some corals.

Once they actuall reach a size where we can see them, most corals on Pacific reefs live a decade or two, though they can theoretically live much longer. On those same reefs it is not at all uncommon to find corals that are many decades or even a few centuries old. Rarely corals may survive to be several centuries old or even over 1000 years. Typically massive Porites and Diploastraea are the corals that will live to be very, very old.

In the Caribbean the corals tend to be a bit longer lived and the average age is likely a few decades. Montastraea spp., which are major reef-builders in the Caribbean, regularly get to be hundreds of years old. Some of the other major reef-builders like Diploria spp., Colpophyllia natans, etc. can get to be very old as well. Acropora in the Caribbean can likely live quite a long time as well, though most of them are dead nowadays.

On the other end of the spectrum, Favia fragum never gets that big. Most are the size of a golf ball or smaller--a size they can reach in a few years--and only rarely will you find one as big as a baseball. Why don't they live a long time and get very big like their relatives? I couldn't say, but nonetheless you'll never find big F. fragum in the field like you will with other Caribbean faviids.