Palau: Out to Sea

Coral reef in Palau replete with juvenile fish (M. Kaplan)

It's day 3 of the Cohen Lab Palau expedition and we are heading out to sea. Since arriving on the night of August 8, we have been busy deploying instruments and collecting coral and water samples on reefs around the island of Koror, Palau. Many of the reefs that we've dived here so far are in excellent condition, and the ones that aren't have largely been affected by natural disturbances (El Nino surface water warming, typhoons, etc.).

A shallow coral lagoon in Palau (M. Kaplan)

I am on this expedition to help collect water samples to study the carbon chemistry and nutrient fluxes of reefs here, which display a natural gradient in acidity as one moves inshore and into shallow lagoons. The fact that corals can thrive in these low pH environments is surprising, given that most experiments and field studies have shown that corals struggle to maintain and grow their calcium carbonate skeleton in low pH waters.

Acoustic recording device (left) &other instruments
(M. Kaplan)

I've also been given the opportunity to collect coral reef acoustic recordings while here. My PhD research is focused on exploring links between biological sound production on coral reefs and the species assemblages present - in other words, what is the link between the sounds produced on a given reef and the fish and invertebrates that live there. Luckily, visual survey data is available for many of the reefs we are going to on this trip, courtesy of the Palau International Coral Reef Center.

At the moment we are preparing to head out to sea, first to collect offshore water samples and then to head south to some of Palau's more remote reefs. This is a rare opportunity to sample in some of these areas, and in part because access is so infrequent we are bringing fuel and a boat for the three rangers that live on one of these remote reefs.


 Max Kaplan