I have posted before on Project BrightEye, which is a satelite based variable wavelength blue-green laser, designed specifically to penetrate deep ocean water to detect and communicate with underwater submarines, as well as for surviellance uses.
Although I seriously doubt that the DoD would ever let this kind of research be done (they dont even admit to the existance of BrightEye), but that is
the perfect tool to search the depths of the uncharted oceans.
BrightEye is already used for essentially taking flash photos of high value targets through inclement weather conditions. I would believe it to be
possible to retask it to take flash photos of the deep sea and find all kinds of large life forms that we had no previous idea existed.