[2] William Dunbar was a Scottish immigrant and scientist living in Natchez, Mississippi, when Jefferson contacted him about the proposed expedition.

[2] Hunter designed the boat that was used on the journey, which resembled a scow and was referred to by members of the expedition as a "Chinese-style vessel.

Dunbar reportedly left the party around Fort Miro in order to take a land route to his home, where he would share the expedition's findings with the government via a transcript of his journal.

[4] The expedition also produced some of the earliest records written in English about the geographical features of Arkansas and Louisiana.

[2] Additionally, records of natural aspects such as plant and animal life in the region around the Ouachita River were kept by Hunter and Dunbar.