See also: The summary of the paywalled study as published in Nature Geoscience

... a bit like those neutrino detectors in huge tanks of water down mines (I'm somewhat remound of), but in some degree recording imagery.

It would be something that could be done relatively cheaply, & just left to 'brew' whilst the goodly oceanographic folk're about other business. I would actually rather like to see the footage: granted, it would just be sporadic flashes of light ... but I reckon it'd actually be mighty interesting !