We recently went to US Virgin Islands to do some preliminary data collection of coral reef soundscapes using a robot. This trip was also our first attempt at deploying a BlueROV2 robot in the ocean.
The robot was equipped with a DMON sound recorder, which enables it to capture underwater sounds at 12KHz. sampling rate.
We made the robot negatively buoyant, which enabled it to rest quietly on the seafloor while recording the hustle bustle of the coral reef.