did well at this, capturing four northern registered vessels. One of these was the icebreaker Enoch Train, which was purchased by private investors and rebuilt as the privateer ironclad ram Manassas. This vessel in turn was commandeered by Commodore Hollins as . Mosquito fleet Blockade of the Mississippi The Union Blockade arrived at the mouth of the Mississippi on May27, 1861, when took up position. This event energized defense efforts in New Orleans and led to the replacement of Rousseau with Commodore Hollins in July 1861 to command the river defense. By August, Hollins had established his mosquito fleet for defense of the river in the area of New Orleans. The fleet consisted of , the flagship , CSS Livingston, , , and Ivy. Ivy was the fastest ship of the fleet and so was made the reconnaissance vessel, with increased firepower. Battle of the Head of Passes Ivy began patrolling the Mississippi River south of Forts Jackson and St. Phillip beginning in September 1861, captained by Lieutenant Fry of the CSN. On September19 she encountered . Water Witch was scouting the Head of Passes for the blockade fleet, which was planning to occupy the Head of Passes and set up a shore battery to control this strategic point. On October 5 Ivy reported the Head of Passes occupied by three vessels of the Union fleet, and shelled them with her bow pivot gun. Returning to the forts, Fry warned Hollins that the Union fleet was establishing a base at the Head of Passes. Hollins decided that the advance of the Blockade Fleet was a significant threat to New Orleans and moved to attack with the entire mosquito fleet. This attack resulted in the Battle of the Head of Passes, a Confederate victory which routed the Blockade Fleet and sent it back to the mouth of the Southwest Passage. Battle of Island Number 10 This victory reinforced the idea in the Confederate War Department that Flag Officer Foote's Union Mississippi River Squadron at the north end of the Mississippi was the greatest threat to the Confederacy. The Battle of Fort Henry, the Battle of Fort Donelson, and the Battle of Shiloh lent a lot of credibility to this idea. As a result, the mosquito fleet and Ivy were ordered to the upper Mississippi and took part in the Battle of Island Number 10. Island Number 10 was a defeat for