I was watching a YouTube video of a Nordhavn 86 being lifted out and noticed it, it seems strange to have something that shape being pushed through the water,but then I not familiar with the "bulb" on small ships.Looks like the mouth of Jaws .
Thanks for that, I thought it was sonar, but for some reason I couldn't find a match, that's why I asked here.Forward looking 3D sonars.
More info here Argos Forward Facing Sonars — FarSounder 3D Forward Looking Sonar for Navigation
and installation pics on various applications including the N86 here
Installation — FarSounder 3D Forward Looking Sonar for Navigation