Research

Our group of researchers, students and technicians contribute to the study of a diverse number of marine habitats that are seemingly not connected. By employing biophysical modeling techniques it becomes clear that all these habitats are connected by their reliance on connectivity. From hydrothermal vents to surface plankton, all the way to coastal coral reefs and mangrove forests, ecosystems rely on inter-connectivity between populations to withstand the many challenges to their survival. By combining genetic techniques and ecological observations with ocean circulation models we study the role connectivity plays in supporting the diverse habitats found around Okinawa Island and beyond.

Biophysical Modeling 

Biophysical modeling is the inclusion of biological parameters within physics based models. In our case this often means including parameters related to larval/planktonic dispersal with models of ocean currents. By using state of the art modeling techniques combined with our own in-situ measurements we are able to forecast oceanographic parameters as well as predict the distribution and connectivity of marine species/populations. 

map of the north east pacific with the ocean artificially shaded dark blue through yellow and orange to red. Left side of the image is a zoomed in section of a long thin island with the same artificially coloured ocean

Plankton 

This diverse group of species is defined by their passive movement which is dictated by ocean currents. The plankton can be separated into two groups based upon their life-cycle. The holoplankton and the meroplankton. Holoplankton spend their entire lifecycle drifting with ocean currents which means that details of their ecology can answer important questions in physical oceanography. Meroplankton only spend part of their life at the whim of ocean currents, often their larval/juvenile stage. These species utilize ocean currents to disperse across the ocean on local, regional and even global scales.

Two microscope images side by side. On the left is a long, thin, spiny organism. The image on the right contains an opaque rounded organism with a pair of dangling tentacles. A scale bar reading one millimeter is placed next to the organism and is approximately half its total width

Coral

Reef building corals are the foundation for one of the most biologically diverse ecosystems on the planet. Through symbiosis with single celled algae, corals are able to utilize the energy from the sun in order to support a highly productive system in areas where nutrients are scarce. Although coral reefs are very impressive in terms of size and complexity, they are also very sensitive to oceanographic conditions and anthropogenic disturbances. By utilizing our knowledge of oceanographic conditions, it is possible to identify which reefs are most at risk and which areas are most crucial to survival due to their important role as a source of new coral larvae.

Side by side images of coral reefs. On the left is a close up image showing dozens of rounded green branches covered in thousands of tiny tentacled discs. On the right is a zoomed out image of hundreds of branching corals packed densely on the sea floor

Mangroves

Mangrove trees form coastal forest habitats that are crucial for the survival of many other species. For many marine species mangrove forests are ideal nurseries and breeding grounds, even human beings benefit from their coastal protection during extreme weather events. Mangrove species have numerous physiological adaptations that allow them to survive in saline coastal waters. Mangroves also exhibit unique reproductive strategies that result in their ability to disperse their offspring over long distances by utilizing ocean currents.

Two images side by side. On the left is a photograph of a dense forest at the edge of calm reflective water. On the right is a photo taken from within a forest densely packed with straight slender trees that have their bases submerged in calm reflective water

Hydrothermal vents

Far below the oceans surface where tectonic activity forces hot magma toward the earth's surface, seawater is superheated below the seabed and released as a hydrothermal vent. Unique ecosystems form around these hydrothermal vents. Ecosystems that survive independent of sunlight but instead rely on the chemicals released from the earths surface. Hydrothermal vents are a perfect case study for answering questions in island biogeography, endemism, genetic connectivity and many other subjects owed to their isolated environment.

Two images side by side. On the left a photograph of a cube shaped-robot with mechanical arms being lowered from the side of a boat. On the right is an image of a craggy rocky surface in dark waters. The bottom portion of the rocky area is carpeted in hundreds of small white crabs. There is date, time and other information stamped over the top and bottom of the image.

Research Facilities

As part of the Okinawa Institute of Science and Technology we have access to state-of-the-art laboratories as well as field equipment and a purpose built marine science station.

Two images side by side. on the left is a photograph of four connected buildings from above. The buildings have modern architecture and are all centred around a smaller building which the other three buildings curve away from. The image on the right is an underwater photograph of a cube frame instrument with a role of yellow wires which sits on the sand, surrounded by coral reef.

(All images credit of Mitarai unit members)