RedactedNarrative: Vessel 1 capsized after taking on water for unknown reason.  No injuries occurred and the two people on board were recovered safely.  Vessel 1, a 17ft. open motor vessel (FL6011DX) was being operated in the vicinity of Blackpoint Marina Channel. Operator stated to me that for reasons unknown to him, the vessel began to take on water causing the vessel to capsize. All persons aboard were recovered and no injuries were reported. Officer and Lieutenant encountered the capsized vessel a day later and verified its location.  Due to the vessel not having been recovered or inspected, I am unable to determine, at this time, the failure or entry point of water into the vessel which caused the vessel to capsize.  operator was provided with the relevant case information in reference to the accident.