2014 Expedition

Low pH site in Nikko Bay, Palau
Photo Credit: H. Barkley

The goal of our work is to identify coral reefs that are best equipped to survive 21st century ocean acidification. The Cohen lab began working in Palau several years ago, during that time we discovered that Palau's Rock Island habitats have an exceptionally low pH for the vast diversity and coral cover that they harbor. All other naturally low pH habitats that science has studied so far, show negative effects: decline in coral diversity, sharp declines in coral cover, and laboratory manipulations show slower growth rates under lower pH conditions. So why are Palau's Rock Islands different? That's exactly what we want to know.

Support for this expedition was made possible by the Dalio Foundation, Inc. Furthermore, our students, Hannah Barkley and Hanny Rivera, are supported by a National Science Foundation (NSF) Graduate Research Fellowship and National Defense Science and Engineering Graduate (NDSEG) Fellowship, respectively.  

Low pH site near Papua New Guinea
Photo Credit K. Fabricius

 Our main goals during our cruise will be to answer: 

• How widespread these acidic “hot spots” are within the Palauan archipelago?
• If the coral communities in these areas are genetically adapted to low pH, or if are there other environmental conditions that enable corals to cope with the pH stress?
• How connected these corals in acidic hot spots are with other coral communities within the Palauan Archipelago? 

Photo Credit: Google Earth

During this cruise we will travel to fifteen different sites across the Palauan archipelago, taking water samples to quantify nutrients, analyze the carbonate chemistry, and other properties such as salinity and temperature. We will also be collecting coral cores, which allows us to study the historical growth of corals in the area. Lastly, we will collect coral tissues to assess the genetic connectivity among different habitats in Palau. 

Our work will allows us to better understand the intricacies of Palau's complex habitats and help identify new sites that will be best equipped to survive upcoming stressors due to climate change. 

M/V Alucia

Photo Credit: H. Rivera

For this expedition will be cruising aboard the M/V Alucia, a unique vessel that will allow us to reach the farthest of Palau's islands and atolls. 

Science Team:

Hannah Barkley 

Hannah's research focuses effective coral reef conservation under climate change, particularly ocean acidification and warming. On this current cruise she will be collecting water samples to study the carbonate chemistry of Palau's various habitats as well as coral cores in order to understand coral growth under different environmental conditions and study the history of bleaching events in the area. 




Hanny Rivera

Hanny is interested in understanding climate change impacts on coral reef ecosystems. In particular she hopes to understand how corals may be able tolerate environmental stress associated with climate change, such as ocean acidification and warming. Throughout this cruise she will be collecting coral tissue samples in order to map coral connectivity in within the Palauan archipelago. 




Kathryn Rose 


Kathryn holds a masters degree in Geology from the University of California, Davis. Kathryn manages the Cohen lab, operates a range of instruments, assists with laboratory manipulation experiments and coral reef fieldwork.








Max Kaplan 

Max's research focuses on characterizing the sounds producing by healthy reef systems compared to overfished or otherwise unhealthy reefs. During this cruise he will be deploying acoustic recorders to record the sounds of Palau's various reef environments. 

Pat Lohmann

Pat Lohmann is Scientist Emeritus at the Woods Hole Oceanographic Institution and is our lead Dive Safety Officer for our expedition.