On 7 December, a group of 17 Confederate sympathizers masquerading as passengers seized the steamer Chesapeake off Cape Cod, Massachusetts.

The panic caused by that daring Confederate exploit prompted the Navy to order Vicksburg on 21 December to take up station off Sandy Hook, N.J., and detain for inspection all commercial ships outbound from New York.

In the spring, while on temporary duty off the coast of South Carolina, the gunboat seized the blockade-running British schooner Indian east of Charleston on 30 April.

Returning to North Carolina, Vicksburg towed the stricken mortar schooner Oliver H. Lee to Beaufort, N.C., on 17 May and 18 May and chased a blockade runner on 31 May, recovering 79 bales of cotton thrown overboard by the vessel's crew.

The gunboat underwent repairs soon thereafter and spent September making an extensive survey of Confederate Fort Fisher and of other Southern land defenses in the Cape Fear River.

She also participated in the bombardment of Half Moon Battery, situated on the coastal flank of the Confederate defense line which crossed Cape Fear Peninsula six miles above Fort Fisher, on 11 February.