I did a little research (I had never heard of the Humboldt current, and now I know something about it - VERY cool) and this is something that I think probably explains why there are not so many corals there:
quote:
The main ocean currents effecting the Galapagos Islands are the cold Counter Equatorial (Cromwell) Current from the west, the cold Humboldt (Peruvian Oceanic and Peruvian Coastal) Current and the from the southeast, the South Equatorial Current from the east, and the warm North Equatorial (Panama) Counter Current from the northeast which brings with it the devastating and infrequent El Ni?o Current. The mix of these currents and the location of the island in relation to the mix cause a wide variation of water temperatures from month to month and island to island.
end quote.
I think the reason you don't find so much coral cover there, even though it is in a place that receives tons of sunlight is that the water conditions are too variable from month to month. also, the humboldt is pretty low salinity. If the other currents are of different salinity, that would be just another variable for the corals to deal with.
...very interesting stuff!
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