Wednesday, February 28, 2007

Corals, divemasters and free divers

I arose at 1:30 am in Toliara to meet the Copefrito fish collection truck for the visit with Blue Ventures. Sixty hours, two trucks, one boat full of octopus and one crowded zebu cart later, I walked into Andavadoaka. I definitely had come a long way from the university. When the BV staff say the road to field site can be difficult, they are not kidding.

I visited with Blue Ventures in January and February to learn a bit about the monitoring programs in Andavadoaka and examine the distribution of coral cover. In the course of my research on climate warming and coral bleaching, I’ve become interested about the response of different corals – different species or growth forms – to temperature stress and the design of Marine Protected Areas (MPAs). Are some corals more susceptible to bleaching? Can some corals recover faster after bleaching? Can this information help us understand how coral communities will respond to further ocean warming and how best to design MPAs?

I was able to accompany the staff and volunteers on dives at the established monitoring sites and at the candidate sites for the MPA. At the start, my routine of photographing corals and jotting down notes, either on my underwater slate or moleskin notebook, definitely seemed strange to the volunteers and most of the staff. For me, though, it was a terrific opportunity to practice coral identification – something I can’t possibly do at home in Princeton, New Jersey! Later on, we all worked together to characterise a few of the candidate MPA sites. While the BV staff and volunteers drew some amazing underwater maps, set transects, counted fish, and did benthic PITs, I did my best to count the number of coral species (by family) and count coral recruits. I was really impressed by the number and diversity of coral recruits growing amidst the rubble at the reefs the fishermen call Empasi and Belamer. I'm anxious to see what the reefs look like in a couple years!

One of the many highlights of my trip was going with new Malagasy divemaster and translator extraordinare, Bic, to interview some of the local fishermen about coral bleaching. I hoped to learn what people understood about corals, and whether they had any memory of mass coral bleaching. There was extensive coral bleaching in western Madagascar in 1998, when the Indian Ocean was abnormally warm, and some isolated bleaching events since.

Bic smartly suggested we talk with the free-divers, as they should know the most about corals. We started with a man Bic called Andavadoaka’s “master” free diver. Parfait doesn’t look like an Olympic swimmer. If anything, he could be considered a wee bit on the chubby side. But he’s endowed with some strong lungs – he regularly dives below 30 metres and can stay underwater for four minutes!

The “master” and the other free-divers were not able to tell us that much about the history of coral bleaching in the region. They all understand that corals can turn white and die, and they all remember seeing it happen before; but, as fishermen, they pay much more attention to the fish! The fishermen did, however, all talk a lot about the importance of healthy coral. A “retired” free-diver named Rolfa told us how most people in Andavadoaka learn at a young age that the fish, the turtles and the lobster all need the corals as a home and a source of food. When and where there is a lot of dead coral – which Rolfa and the others recall happening during some particularly rough, wavy winters – there is little to catch on the reef other than sea urchins. Although some of my questions about bleaching went unanswered, I got an unexpected lesson on the extent of traditional knowledge of reef ecology in Andavadoaka.

Simon Donner, visiting researcher from Princeton

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