the Confederate fleet in New Orleans was transferred up the Mississippi River to support the Confederate defenses of Columbus, Kentucky, but Oregon remained behind, serving on Lake Pontchartrain and intended to help other ships defend the coasts of Louisiana and Mississippi. On December 7, 1861, the gunboat CSS Pamlico sighted Union vessels entering Mississippi Sound. Oregon was present at Mississippi City, Mississippi, to transport equipment for a powder mill from there to New Orleans, and joined Pamlico in confronting the Union ships, which turned out to be the steamers USS New London and USS De Soto. Remaining in shallow water that the Union vessels could not enter, the Confederates fired on them with two rifled cannon. Oregon and Pamlico ignored a challenge from New London for a closer quarters fight, and the Union ships withdrew. Pamlico then escorted Oregon back to New Orleans, where the latter unloaded the power mill equipment, which increased the city's capacity for gunpowder production. After meeting a blockade runner in Lake Borgne, Pamlico and Oregon attempted to escort her into the Gulf of Mexico on December 20, but were detected by Union forces near Ship Island and forced to withdraw back to Lake Borgne. On March 25, 1862, Oregon was escorted by Pamlico to the Pass Christian area to deliver supplies and then on her own moved towards Ship Island to scout Union positions. Withdrawing to Pass Christian after being sighted, she was pursued by New London. Oregon and Pamlico moved to engage the Union ship, and began firing from a range of . Two of Pamlicos cannons were unable to be fired safely due to defective ammunition, and after Pamlicos third cannon was rendered unusable after a projectile became stuck in the barrel, the two ships withdrew into shallow water, where New London could not pursue. The Union ship fell back several hours later. On April 3, New London, the steamer USS John P. Jackson, and the troop transport USS Henry Lewis left Biloxi, Mississippi, to move against Pass Christian. Pamlico, Oregon, and the gunboat CSS Carondelet were mobilized to counter the threat. In an action offshore of Pass Christian, Confederate fire forced Henry Lewis to withdraw, and the other Union vessels suffered light damage. Oregon suffered a hit to her ship's wheel, and her pilot was wounded when a projectile entered the pilothouse. With Carondelets wheel also damaged in the battle and the