Ulua Beach Mystery

Over the past couple of weeks I have had several scuba divers, as well as our staff, come into Maui Dreams and ask  “What is that thing at Ulua Beach? Is it a bomb!?!”

As it turns out, it is an important scientific listening device placed at Ulua Beach (and seven other underwater locations around Maui) by scientists working with Woods Hole Oceanographic Institution and Oceanwide Science Institute.

Maxwell Kaplan and Marc O. Lammers, PhD, along with Aran Mooney and others, have been installing, monitoring, and maintaining these devices since September 2014. In addition to the one at Ulua, there are also units at Honolua, Old Airport (Kahekili), Mile Marker 17 (on the West side), Olowalu, Red Hill, Ak Nar (south of Makena), and Molokini Crater.

Have you ever noticed the sounds you hear underwater? I hear the Hawaiian Dascyllus Damsel fish making a purring noise (which may be a territorial signal), as well as the snapping shrimp sounds, especially at night. These types of sounds are exactly what these scientists are recording and analyzing, along with sounds that are probably out of our range such as dolphin echolocation clicks. The recorders are serviced and the information is collected periodically. At that time, the team conducts a reef survey. The next servicing will take place in June 2015.


Max Kaplan asks, “Can we put an acoustic recorder on a reef and learn what lives there and how that changes over time, based only on the sounds we record? If so, it will be much easier and less expensive to track changes in marine ecosystems, especially in hard-to-reach places.”

Max and Aran

Max’s team also hopes to learn about the “diversity of sounds produced by reef animals, acoustic monitoring of coral reefs has great potential as a management tool.”

Though the recorders will work best if left undisturbed (so please don’t handle them in any way), divers are welcome to take photos and Max is definitely interested in looking at the growth that occurs on them over time, as well as learning about what’s going on around the devices. If you have information or photos to share or questions to ask, Max welcomes your emails.

The devices will be removed at the end of their permit with the Department of Land and Natural Resources in August 2015.  In the meantime, interested divers are invited to view Aran’s blog.

You can click here for more information on sensory physiology and sensory ecology studies and here to learn more about the “EAR” or Ecological Acoustic Recorder.

And if you are interested in learning what marine life inhabits our local reefs here on Maui, consider taking our class on Project Aware Fish Identification!

Aloha, Teri