Quadrats

The Coral Queen descending with quadrat
Today was my first research dive. I went out with Katie, the Coral Queen here in Tofo, to monitor one of the many patchy reefs here. We were diving Simon's Town Reef. Katie carried a quadrat, which is a 1 meter square piece of plastic used to standardize the measurement of coral activity, and I carried an underwater camera.

The idea is to photograph what's in the quadrat and then analyze it later to see what is growing in the reef. It's a two-person job because it's not possible to hold the quadrat in one hand and take the photo with the other without losing control and damaging the coral, particularly in strong current. And Katie always says, the coral comes first. There's no point in monitoring the health of the reef if doing so destroys it.

It seems easy at first, until I realize how hard the shots are to frame. I want the edges to be squared off with the quadrat, but somehow as soon as I've got the camera ready I realize I've drifted from where I'd originally lined up.

Quadrat containing coral and a starfish
At the time I thought I was nailing it but after the dive we looked at the photos on our macs and I discovered they were much blurrier and more poorly aligned than I'd originally thought. It seems this takes some practice. The Coral Queen says they'll work fine though in conjunction with the video footage I took. We just need to load them into CPCe (coral analysis software).

We also logged a ton of information from the dive itself, like surface temperature, bottom temperature, what types of plankton were in the water column, animal species sighted, etc. Thank goodness I had a marine biologist with me who actually knew how to identify these things, I'd be pretty thoroughly lost on my own.

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