Tortoises on the caldera rim in 1983
I thought I'd put a few photos of Alcedo on the web, in the event anyone is interested. I'm not much of a photographer, and I've spent nowhere near the time on the volcano as some others. But I've spent a couple months total on the volcano in 5 separate visits, so I have a fair personal experience of the goat infestation there. To cut to the chase: Alcedo at one time was my favorite place on earth. The rocks are incredibly cool, it holds the greatest population of giant tortoise on the planet, and I have worked there with some great people. But now it is process of being destroyed by a population explosion of introduced goats.
I first visited Volcan Alcedo while a grad student, in 1983. At that time, Alcedo was a pretty wild place; the path to the summit was very hard to follow, and we certainly didn't see anyone in the three or four days we were there. There was a herd of donkeys in the caldera floor, and we saw no goats. In fact, getting down to the geyser involved some pretty heavy machete work through the vines.
The slope is now nearly bare. All of the trees are trimmed of vegetation to about 2 m. We observed in 1995 that the goats were pushing over trees to get at the foliation.
My main work on Alcedo was in 1989, when I spent 5 weeks there with students. We lived in this camp on the southern caldera floor most of the time. We had galapagos in our camp constantly. The walk from here to the obsidian flow was easy if you are a tortoise, but we had to crawl a fair distance. In that entire time span (and walking hundreds of kilometers), I saw two goats on the lower west flank and four others on the east coast (and we nabbed those).
This area is now virtually defoliated.
In 1991, Alcedo began some serious volcanic rumbling. Alcedo had a very powerful explosive eruption that produced all the pumice on the east side (we think it was 90,000 years ago, but that is unsure). So I went down for a quick visit to see if anything serious might be imminent. I met Miton Friere at his camp and was startled to learn that there were hundreds of goats inside the caldera.
The verdant scene is mostly because this visit was in March. I can testify that most of what you see here is now defoliated.
Tui DeRoy and Lynn Fowler describe the disaster at Alcedo better than I could, but my visit this year (to collect a few rock specimens for age determinations) was heartbreaking. I would describe it like "camping in a feed-lot" (apologies to those of you not from the western U.S. - a feed lot is a small parcel crowded with hundreds of cattle and fed grain. It stinks. Bad.). We circumnavigated the caldera and saw thousands of goats.
As alluded to above, the goats have made a good start at defoliating the volcano. Soil erosion on the caldera walls is very serious and compounded by the increased hydrothermal activity. I have no idea what is to become of the tortoises and other unique biota from Alcedo. But I applaud the efforts of Tui and Lynn in raising money for goat eradication, Linda for her work with the tortoises there, and the hunters from the Park for doing the brutally hard work of hunting the goats down.
The Galapagos Coalition has a great web site!