A ship owned by Kanzaemon from Asakawa-ura of Awa Province was shipwrecked on its way to Edo loaded with mikan (tangerines) from Kishu Province, drifted to Hahajima in February 1670. The crew landed on Hahajima, where they spent approximately 50 days exploring the island, repairing their ship and securing food supplies.
They reported the situation of the island as follows.
 

• The island is only 10 ri (approx. 40 km) in circumference, and the mountain is slightly higher than that on Izu-Oshima.
• There is one place on this island that could serve as a harbor. This harbor faces southwest, is about three cho (approx. 300 m) wide, and could anchor 20 to 30 vessels. The depth is two hiro (approx. 3.6 m) at low tide and four hiro (approx. 7.2 m) at high tide, and there are three islets approximately one ri (4 km) from the harbor.
• There are no signs of people living on the island, nor any signs of upheaval or damage.
• There is one place that could be used for planting crops.
• There is an abundance of water.
• There are large muku, Japanese whitebark magnolia, and Indian soapberry trees with trunks of a girth as much as two or three men, and there are also trachycarpus palms. Grasses, there are of a species never before seen. There are also a few red stones the size of a fist.
• There appear to be no dangerous beasts on the island.
• Birds on the island included bush warblers, blue rock-thrushes, turtle doves, crows, as well as a persimmon-colored bird in the shape of a night heron, a bird in the shape of a female chicken with a red head, black feathers and red bill and feet, and a bird that resembled a sea gull that catch fish.
• There are fish of all sizes around the island including black seabream, grey mullet, shrimp as long as three shaku (91 cm), octopus, and turtles, as well as many shore fish like those on the mainland. Abalone-size limpets are clinging to the rocks. Around February and March many whales are also seen.
• The weather in February on the island is as hot as that of May on the mainland, and in March the weather is as hot as June. The heat increases in April, making it almost impossible to walk barefoot across the rocks, and we all took our clothes off on the island. There are many flies and mosquitoes, which come out a lot during the day, but not at night. (Ref. 1)

Ref.1 ： “A written statement by three boatmen/sailors [Kako] of Yasubei, Hikonojo and San-emon from Asakawa-ura, Kaifu County, Awa Province” (two editions of the document), Stories of Drifting on a uninhabited Island during the Era [Kanbun], a Japanese era name for the earlier years of the Edo period (manuscript copy, 1875), reposited at the National Archives of Japan

Related documents
“A written statement by three boatmen/sailors [Kako] of Yasubei, Hikonojo and San-emon from Asakawa-ura, Kaifu County, Awa Province,” Historical records of the Ogasawara Islands, vol. 27