Aquatic mammals have been observed in the canal only rarely and in cases of severe distress. A harp seal was observed in the canal in 2003, its flippers bloodied, but it survived and was relocated to the Long Island Sound. In 2007, a young minke whale ended up in the canal as a result of heavy storms. The whale, soon nicknamed "Sludgy", was unable to get out and soon died. A necropsy of Sludgy, performed by animal anatomist Joy Reidenberg, indicated that the whale had already been sick. On January 26, 2013, a dolphin entered the canal at low tide, was unable to get out, and died. A necropsy showed that it was middle-aged and sickly before becoming trapped. It had kidney stones, gastric ulcers, and parasites.