In 2009, after accepting a position at the National Science Foundation, I wrangled a postdoctoral fellowship for David Baker. Baker, a grad student from Cornell University, visited the Geophysical Lab a couple of times asking for a postdoc so he could continue his work on isotopes in corals. Finally, I recognized that here was a determined, smart young man who had a vision of how he wanted his career to unfold. He managed to get a matching fellowship at the Smithsonian, which opened up the possibility of going to Twin and Carrie Bow Cayes again. At the same time, Derek Smith, a former student from James Scott’s lab at Dartmouth was working on his Ph.D. on purple sulfur bacteria. We developed close ties with each other, including afternoon trips to the Lab’s attic where a small gym allowed us to benchpress weights and have some laughs.
|Dave Baker, Belize
Every few days, we would go off shore or near another coral island, so they could collect samples for later experiments and isotope measurements. Derek and I were responsible for staying in the boat and figuring out when and where the divers would surface. One particularly choppy day just off shore Carrie Bow, we waited anxiously for the dive “balloon” to surface so that we knew where they were. That particular day, Chris was to hold on to the balloon, but he forgot to attach it to his wrist. I was concerned that our propellers would hit them as they surfaced. Derek was concerned that as we drifted, we’d end up on the reef. We drifted about 100 m from the divers, but learned some important boat safety and gained some confidence. Baker and Freeman were pretty surprised when they surfaced and saw the boat quite a distance from them.
Baker was interested in studying the effects of nutrient additions to coral’s symbionts. His field areas included Australia’s Great Barrier Reef, Panama, Florida, Mexico, and now Belize (Baker references). Chris Freeman, a grad student at the Univ. of Alabama, studied the microbial aspects of coral symbiosis. With their coral collections, Dave and Chris set up a series of experiments with small 5 cm pieces of a couple of coral species that were incubated in temperature controlled pools on Carrie Bow. Each morning and evening they measured dissolved oxygen levels in their experimental bottles to determine respiration and photosynthetic rates.
At night we also extracted chlorophyll from corals and measured nutrients. At the end of a long day, outside under the stars, we had a glass of One Barrel rum. One evening, I introduced the gang to Panty Rippers, a favorite of Mat Wooller. Two parts coconut rum and one part fruit juice of your choice. Shake with ice and serve. Although much more palatable to me, the others were rather foggy the next day. Henceforth, they stuck to plain rum.
|Lionfish--invasive, poison spines, but tasty
I was treated to the thrill of seeing “my” mangrove trees again. I took the group to all of the major sites I’d published on. With Derek, we waded through an interior pond with 1.5 meters of microbial soup, a thick gelatinous mass of anaerobic microorganisms, many of which were purple sulfur bacteria. One day we traveled to one of the other coral islands so they could dive to deeper waters looking for corals with unusual types of Symbiodinium. The boat was anchored near a steep dropoff going from a shallow 2-3 meters to about 25 meters depth. Dave and Chris donned their scuba gear, dropped off the side of the boat, checked the anchor then descended.
|Marilyn, Dave Baker, and Derek Smith