[Coral-List] crown-of-thorns starfish outbreak in American Samoa
douglasfennertassi at gmail.com
Tue Nov 18 02:27:40 EST 2014
I forgot to say in my post that the Morello article is available
open-access from MEPS.
On Sun, Nov 16, 2014 at 3:58 PM, Douglas Fenner <
douglasfennertassi at gmail.com> wrote:
> Crown-of-thorns starfish sightings in American Samoa have been
> increasing for over a year. They are now to the point that they are eating
> significant amounts of coral. Efforts are underway to try to kill
> significant numbers of them by injecting them. Efforts have been
> increasing as their numbers have been increasing, but their numbers
> continue to increase. I'm told that (independent) Samoa, which used to be
> called Western Samoa and is in the same archipelago, has a similar
> problem. My guess is that the increases in those visible (and the feeding
> scars) comes from more and more of them who have been in holes in the reef
> all the time, coming out to feed on coral. I'm told that their sizes have
> been increasing, but of course virtually all that are seen are already
> nearly a foot in diameter or more. The increases we've seen in the last
> year are unlikely to be due to continued reproduction, it is due to those
> in holes coming out as they grow. But the large numbers now present, may
> well produce a large number of eggs and the next generation could be a much
> larger secondary outbreak.
> Efforts to control them are an uphill battle. The last previous
> outbreak here peaked in 1978, when there were millions, and they ate around
> 90% of all the coral. Over 400,000 were collected then before the money
> ran out, and had no effect on their numbers. Efforts started much earlier
> this time, in hopes of controlling it before it became uncontrollable.
> There was a previous outbreak that we know little about, in 1938. In
> 2005-2012, coral cover increased in American Samoa, a bit of a success
> story, which is now treatened.
> All this makes sense to me from what is known of crown-of-thorns
> Birkeland, C. 1982. Terrestrial runoff as a cause of outbreaks of *Acanthaster
> planci* (Echinodermata: Asteroidea). Mar. Biol. 69: 175-185.
> Birkeland, C. 1989. The Faustian traits of the crown-of-thorns
> starfish. American Scientist 77: 154-163.
> Brodie, J., Fabricius, K., De'ath, G., and Okaji, K. 2005. Are increased
> nutrient inputs responsible for more outbreaks of crown-of-thorns
> starfish? An appraisal of the evidence. Marine Pollution Bulletin 51:
> Morello et al. 2014. Model to manage and reduce crown-of-thorns starfish
> outbreaks. Marine Ecology Progress Series 512: 167-183.
> Douglas Fenner
> Contractor with Ocean Associates, Inc.
> PO Box 7390
> Pago Pago, American Samoa 96799 USA
> phone 1 684 622-7084
> "belief in climate change is optional, participation is not."
> belief in evolution is optional, use of antibiotics that bacteria have not
> evolved resistance to is recommended.
> website: http://independent.academia.edu/DouglasFenner
> blog: http://ocean.si.edu/blog/reefs-american-samoa-story-hope
Contractor with Ocean Associates, Inc.
PO Box 7390
Pago Pago, American Samoa 96799 USA
phone 1 684 622-7084
"belief in climate change is optional, participation is not."
belief in evolution is optional, use of antibiotics that bacteria have not
evolved resistance to is recommended.
More information about the Coral-List