THE HARBOR COLUMN:

My radar is showing two blips you should plot in your calendar. First blip and closing fast is the 16th Annual Orange County Boat Show at the Anaheim Convention Center from April 3-6. Go to www.orangecountyboatshow.com. The second blip is the 35th Annual Newport Boat Show at Lido Marina Village on April 9-13, and we will be broadcasting live from the village on April 12. Go to www.newportinwaterboatshow.com.

Tip of the week is a question people ask me constantly: “Why do some boats have a sticker with what looks like license plate numbers on each side of the bow, and other boats do not have any type of licensing showing on the boat?”

Almost all watercraft — whether a boat, vessel, ship, raft, dinghy, etc. — must be either documented with the U.S. Coast Guard or registered with the Department of Motor Vehicles. The few exceptions that do not require licensing are, for example, a small sabot sailboat without an engine attached, a canoe-type vessel powered only by oars and tender vessels for ships.

Vessels with the numbers displayed on the bow are typically boats shorter than 40 feet and are used solely for recreational cruising. In California, we call these vessels CF’d registration — CF is the start of the registration numbers and refers to California.

Larger boats, ships and all commercial vessels are documented with the Coast Guard, and as such, do not display any registration numbers. These boats have a U.S. documentation number affixed to their internal structure and use the vessel’s name and hailing port for identification.

So when do you document versus CF? If your vessel is over five gross tons (internal size calculations not the actual vessel weight), used for commercial purposes or travel internationally (including Mexico), documentation is for you. Say you sail only in Newport with your Cal 20, then CF. If you want to document, I recommend calling one of the documentation companies in Newport to file the paperwork for you with the Coast Guard. Keep in mind that your 65-foot yacht will be documented with the Coast Guard, and the dinghy carried onboard that yacht will be registered with the DMV.

Remember to tune in every Saturday at 11:00 a.m. to “Capt. Mike Whitehead’s Boathouse Radio Show” on AM 830 blasting to Southern California.

MIKE WHITEHEAD is the Pilot’s boating columnist. Send marine-related thoughts and story suggestions to [email protected] or go to www.boathousetv.com.