Given the record number of shark sightings and attacks off Southern California this spring, it’s about time we had a shark encounter of our own out here! Unfortunately, yesterday marked the first shark-related casualty of the trip: an autonomous carbon flux explorer (CFE) from Jim Bishop’s group at UC Berkeley.
The CFE was scheduled to surface and be recovered by the ship yesterday afternoon. Around 4:30 p.m., as we neared the bobbing blue cylinder of the CFE, a dark fin appeared on the horizon. It circled a couple of times and then chomped down on the CFE, killing the instrument’s signal and any hope for its recovery. We think the shark was a short-fin mako, but we now know for a fact that CFEs resemble seals bobbing at the surface.
Fortunately Bishop’s team (which also consists of technician Todd Wood, graduate student Hannah Bourne, and undergraduate assistant Sylvia Targ) has three other CFEs that they will continue to deploy for Cycle 4. CFEs capture and image subsets of sinking particles in the ocean, as a way to determine how much carbon is transported below the ocean’s surface and what kinds of fecal pellets and detrital fluff dominate production. This information helps quantify the ultimate fates of surface-produced phytoplankton carbon and particles, which are important components of the ocean’s essential role as a sink for atmospherically-produced carbon.
Posted by: Laura Lilly, SIO