USCG requirements for kayakers paddling at NIGHT:
1. Carry a white light that can be turned on to warn other vessels of your location in time to prevent a collision.
2. Carry THREE USCG approved visual distress signals (i.e. three flares). There are a variety of visual distress signals, however keep in mind that for night time you are limited to signals that produce their own obvious light, i.e. flares and strobes. There are also bright signaling flashlights that can be set to flash S.O.S. and also be used as a warning light in case of preventing a collision. These lights have USCG approved number 161.031 on them and replace the need to carry three flares. A normal flashlight does not meet USCG standards.
A note about Strobe lights: Strobe lights are legal distress signals only on INLAND WATERWAYS. Inland waterways are those regulated by Inland Navigation Rules as opposed to International Rules. There are NO simple guidelines for knowing which is which. "Puget Sound and connecting waters, including Lake Union and Lake Washington, are called INLAND WATERS, by the National Weather Service and the USCG licensing division, BUT they are INTERNATIONAL WATERS according to Navigation Rules." Thanks to D. Burch, "Fundamentals of Kayak Navigation"