Following Vitus Bering's 1741 tragic venture he was the first to conduct an expedition to Alaska and the Aleutians.
Krenitsyn was sent, together with Mikhail Levashev, by Russian Empress Catherine II to explore the northern parts of the Pacific Ocean and particularly the area around the Bering Strait in four ships.
[1] Krenitsyn and Levashev surveyed the eastern part of the Aleutian Island chain until the cold weather set in.
Certain geographic features of the Alaskan coast, like Avatanak, Akutan and Tigalda Island were named by Krenitsyn in the maps that were subsequently published.
On July 4, 1770, Krenitsyn drowned in the Kamchatka River and Levashev assumed command of the Russian expeditionary fleet.