Butler's army, aided by Flag Officer David Farragut's fleet, captured New Orleans on April 29, 1862. Dow and the 13th Maine did not join in the attack, remaining behind to guard Ship Island. A day earlier, Congress had approved Dow's promotion to brigadier general. He blamed Butler for excluding him from the battle, believing that Butler was threatened by his promotion and calling him a "bully and a beast". He spent much of the time quarreling with his second-in-command, Lieutenant Colonel Francis S. Hesseltine, while the regiment occupied forts around New Orleans. While there, Dow encouraged black slaves to run away from captivity and take shelter with the Union Army. He also confiscated property from nearby planters, including those who supported the Union, and tried unsuccessfully to claim personal salvage rights over Confederate military property abandoned in the river.