Flag Officer Josiah Tattnall and his mosquito fleet saw their share of action during the Battle for Port Royal. Tattnall had a reputation for aggressiveness, and he certainly displayed it at this engagement. On 4 November 1861 Flag Officer DuPont of the Union fleet sent the survey vessel Vixen in to chart the configuration of the bars and channel into Port Royal, accompanied by the gunboats Ottawa, Seneca, Pembina and Penguin. Tattnall, on his flagship, the steamer CSS Savannah, and with three armed tugs (Lady Davis, Resolute, and Sampson), bravely headed in towards the USN vessels. Gunfire from Ottawa, Seneca, and Pembina drove him back to his anchorage in Skull Creek. The next day, USN gunboats led by Ottawa went in to probe the defensive capabilities of the Confederate shore batteries and the CSN fleet attacked again. This time the Confederate flotilla was under the command of John Newland Maffitt, who, as Robert Browning notes, “went at them” when he saw the enemy vessels steaming into the harbor. A shot from the Seneca’s forward 11 inch pivot gun struck the Savannah and again the Union gunfire forced the Confederate ships to withdraw. Tattnall was furious with Maffitt, claiming that he did not authorize an attack, and of course Maffitt believed otherwise. Tattnall relieved Maffitt of command, but the two officers later settled their dispute. The day the Union offensive began (7 November), the mosquito fleet, back under Tattnall’s command, again stood out to take on the USN attacking fleet. A flanking column of Union gunboats (Bienville, Seneca, Penguin, Augusta, and Curlew) was assigned to keep watch on the mosquito fleet and fend off any attacks, which they did. Tattnall, as he reluctantly withdrew, dipped his blue ensign three times as a salute to his old friend DuPont. Later that day, Seneca went after the Confederate vessels and drove them back to Skull Creek. After the capitulation of the forts, the CSN vessels helped evacuate the Confederate garrison.
Image of the "90-day" or Unadilla class gunboats. Ottawa, Pembina, and Seneca are all shown. Source: Naval History and Heritage Command