かもゐ丸 Kamoi Maru (JANAC)

Some accounts say Wahoo sank the Japanese submarine I-2 on 14 December 1942. However, no Japanese submarine was lost on this date in Wahoo's patrol area. I-2 reported being attacked, but submerged and sustained no damage. Explosions heard by both sides were likely premature detonations of Wahoo's torpedoes. I-2 was sunk on 6 April 1944 by USS Saufley (DD-465).

Patrol 3

IJN Harusame - damaged

Cargo Ship (name unknown) of 4,000 tons estimated (unverified but included in JANAC)

武洋丸 Buyo Maru (JANAC)

＃２福栄丸 Fukuei Maru #2 (JANAC)

Unknown Maru (unverified but included in JANAC) - misidentified as Ukishima Maru in some sources

Pacific Maru - damaged

広和丸 Kowa Maru (JANAC)

保山丸 Hozan Maru (JANAC)

日通丸 Nittsu Maru (JANAC)

Cargo Ship (name unknown) of 2,427 tons estimated (unverified but included in JANAC). Possibly Gyoun Maru, 912 tons, attacked but not hit.

高雄山丸 Takaosan Maru (JANAC)

増源号 Zogen Go or Zogen Maru (listed in in JANAC as "UNKNOWN MARU")

皐月丸 Satsuki Maru (JANAC)

Cargo Ship (name unknown) of 2,556 tons estimated (unverified but included in JANAC)

Bonshu Maru #95 - damaged

Unknown - damaged (Sampan)

Unknown - damaged (Sampan)

山鳩丸 Yamabato Maru (JANAC)

Kimikawa Maru - damaged

第五多聞丸 Tamon Maru #5 (JANAC)

高雄丸 Takao Maru (JANAC)

神武丸 Jimmu Maru (JANAC)

Unknown - damaged

Ryokai Maru - damaged

Terukawa Maru - damaged

Unknown (Sampan) (not included in JANAC; small vessel often not included in sinkings)

Inari Maru #1 (Sea Truck/Sampan, 33 tons) (not included in JANAC)

Unknown (Sampan) (not included in JANAC; small vessel often not included in sinkings)

Unknown (Sampan) (not included in JANAC; small vessel often not included in sinkings)

北征丸 Hokusei Maru (not included in JANAC)

大湖丸 Taiko Maru (not included in JANAC)

＃２正木丸 Masaki Maru #2 (JANAC)

崑崙丸 Konron Maru (JANAC)

漢江丸 Kanko Maru (JANAC)

漢江丸 Kanko Maru (JANAC) or Hankow Maru - see note below

Note: USS Wahoo was lost on this patrol.

Regarding 漢江丸 Kanko Maru and 漢江丸 Kanko/Hankow Maru:

Research indicates that these are two different ships with the same name (in kanji) but with possibly different readings of the name.

The former (Kanko Maru) was a 1,290 ton cargo vessel built by Chosen Kisen, and was sunk off the east coast of Korea on October 6, 1943, at 37-18N, 129-33E.

The latter (Kanko Maru or possibly Hankow Maru) was a 2,995 ton cargo vessel built by Iino Shipping Company, and was sunk off the Oga Penninsula, Honshu, Japan, on October 9, 1943.

Adding to the confusion, the coordinates of the sinkings given in JANAC listings are mistakenly the same for both vessels. Both are listed as being sunk at 37-18N, 129-33E (off the coast of Korea). The sinking coordinates of the second Kanko/Hankow Maru, sunk three days after the first, should be 39-49N, 139-46E, off the west coast of Honshu, according to Japanese sources.

Current research credits Wahoo with sinking 19 ships sunk totalling 55,362 tons. These figures do not include the first two "UNKNOWN MARUs" credited to Wahoo but listed as unverified in Alden and in Japanese sources. However, they do include the third "UNKNOWN MARU," identified in Alden as Zogen Go (Zogen Maru in some sources), as well as Hokusei Maru and Taiko Maru. Inari Maru #1 and three other unidentified sampans sunk by Wahoo on her 6th patrol are not included.

JANAC credits Wahoo with 20 ships sunk totalling 60,038 tons. JANAC includes 3 ships that are referred to as "UNKNOWN MARU" totalling 8,983 tons, only one of which (Zogen Go) has been verified by Alden and current research.

Note that the criteria JANAC used included all Japanese Naval vessels (although JANAC did not usually count warships less than 500 tons that were converted from merchant ships) and all Japanese merchant vessels of 500 or more gross tons known or believed to have been lost during the war. Differences between JANAC figures and current research are noted above.

Alden-McDonald credit Wahoo with 19 ships and 55,362 tons sunk, plus four small ships sunk by gunfire on Wahoo's sixth patrol. They also credit Wahoo with damaging 10 ships (3 of them of less than 100 tons each), totalling 35,015 tons.

War Patrol Reports and Endorsements credit Wahoo with 27 ships and 227,493 tons sunk.

SORG credits Wahoo with 31 ships and 227,800 tons sunk, plus one ship damaged, 4,100 tons.

JANAC - https://www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/j/japanese-naval-merchant-shipping-losses-wwii.html

JANAC - https://www.ibiblio.org/hyperwar/Japan/IJN/JANAC-Losses/JANAC-Losses-6.html

SORG - http://archive.hnsa.org/doc/subreports-sorg.htm (Excel spreadsheet download)

Archives of the Pacific Fleet Submarine Museum (PFSM)

War Patrol Reports - USS Wahoo - https://issuu.com/hnsa/docs/ss-238_wahoo

Japanese Merchant Ship Losses

Monthly Losses of Combatant and Non-Combatant Vessels

太平洋戦争時の喪失船舶明細表（汽船主体） - Lost Vessel Table during the Pacific War (Merchant Vessels)

Alden, John D., and McDonald, Craig R. - U.S. & Allied Sub Successes in the Pacific & Far East during WWII - Fourth Edition, 2009

Cressman, Robert - The Official Chronology of the U.S. Navy in World War II, Naval Institute Press, 2000.

O'Kane, Richard H., Wahoo: the Patrols of America's Most Famous World War II Submarine

Sterling, Forest J., Wake of the Wahoo, R. A. Cline Publishing, 1999

NHHC - Loss of USS Wahoo (SS-238) and Lieutenant Commander “Mush” Morton

Imperial Japanese Navy Page - http://www.combinedfleet.com/

Wrecksite - https://www.wrecksite.eu/wrecksite.aspx

Wikipedia Japan - https://ja.wikipedia.org/wiki/ワフー(SS-238)

Japan Center for Asian Historical Records (abbreviated as JACAR or JCAHR) - National Archives of Japan -https://www.jacar.go.jp/english/index.html (English); https://www.jacar.go.jp/index.html (original Japanese)

https://ameblo.jp/harimano-kami/entry-12630659978.html

Miramar Ship Index - https://www.miramarshipindex.nz/

Official U.S. Navy Photos - Naval History & Heritage Command

Archives of the Pacific Fleet Submarine Museum (PFSM)

Japanese Merchant Ship photos - Wrecksite - copyright owners retain all rights. Photos used on this site will be taken down should the owner request their removal.

Explanatory Note

On individual ship pages, "Attack No." refers to the number assigned to the submarine attack by authors John D. Alden and Craig R. McDonald as shown in their work, United States and Allied Submarine Successes in the Pacific and Far East During World War II - Fourth Edition, McFarland & Company, Inc., Jefferson, North Carolina, and London, 2009.

The number is a unique identifier from the source of data that is the basis of this presentation.