Friday, November 6, 2009

Alacranes Blog 3

Did you know that there is a link between sea birds and coral reefs? I didn’t know that until just before came on this photographic expedition. A friend of mine at UCSC put it plainly. Bird droppings, are a fertilizer for coral. I’d never put these things together, and always sort of looked at birds as takers, not givers in the ecological cycle of the ocean.
So, instead of just taking other peoples word for it, I did a little bit observing while I was on Alacranes. I dove well over a dozen different locations on the reef. Some of the dives were greatly separated from the islands which hold colonies of nesting gannets and frigate birds, and other dives where just down current from these islands.

The evidence startled me to say the least. It is hard to isolate the corals that are bleaching from rising ocean temperature, toxic pollutants from boats, or just plain human impact from fishermen and tourists alike. There was however an obvious vitality to the reefs that were just down current from the islands. They thrived, the coral suffered less bleaching, the fish were more numerous, and things seemed to be balanced.

Before I came to Alacranes I got in touch with Island Conservation, a group out of Santa Cruz, California. I offered to do a little bit of reconnaissance for them, as they are expanding their conservation efforts to include the gulf, and the Caribbean.

We know that sea birds are suffering, and that their numbers along with everything else are in decline. One of the problems is the invasive species, that - no surprise - humans have introduced, mostly without even knowing we’d done it. On an island that had few natural predators for these birds since they first came here, suddenly, rats have shown up, and are eating the eggs and the young birds that not too long ago had nothing to worry about.

So far, the problem isn’t completely out of hand here. The birds don’t nest year round, and the rats don’t have much to survive on when the birds aren’t nesting, save the trash left behind by tourists, and leftovers dumped out by the park rangers. So for now, the birds are okay. None the less, it is a problem that we will need to address at some point.

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