Mobile, AL – Two Navy ships with combined crews of nearly 400 sailors will arrive in Mobile Thursday for Mardi Gras. The port city's tradition dates back to 18-98. However, this year security concerns will limit public tours of the vessels. Only the smaller of the two ships will be open for public tours. The 188-foot coastal mine hunter U-S-S Osprey is expected to arrive at Mobile Landing at nine a-m- Thursday. It will be open for public tours from 1 to 5 p.m. Friday through February 24th. This year's official Mardi Gras ship, the 505-foot-long U-S-S Stout guided missile destroyer, will remain closed to the public.