The Oh-Mah of the Hupa is not any kind of Bigfoot. Once again I will link to the research:
http://www.internationalskeptics.com/forums/showpost.php?p=3389527&postcount=60
The Oh-Mah is the Raak nee 'ue-ma-'ah, the sorcerer creek devils "were thought to live in dark, bushy thickets, and they had magical arrows of burning flint with which they could kill someone who passed nearby." In none of the research that I have done have I found any reference to the Oh-Mah being something other than these sorcerer creek devils until later in the twentieth century, and then only in Bigfoot enthusiast sources. It would seem the retconning of Oh-Mah as Bigfoot is a cultural contamination distorting the nature of the original tales.
It has also been said in certain Bigfoot sources (mostly Bobbie Short's Bigfoot Encounters) that the Hupa know Bigfoot as "tintah-k'iwungxoya'n" (translates to the old man of the woods). It is my contention that Bigfoot is something created by North Americans of European descent. During the twentieth century when Bigfoot became a cultural phenomenom and many Bigfoot enthusiasts felt sure they would find correlaries in native mythology, they pushed the idea on various groups in an appeal to their "ancient wisdom." Some of these groups abided in offering whatever might seem closest. Indeed I have found once again a native language resource having an entry for Bigfoot (the first time was Salish).
From the Hupa language text Now You're Speaking - Hupa under the section heading "Little Friends" between Grizzly and Coyote
Bigfoot - tintah k'iwungxoya:n
woods / old man
http://dscholar.humboldt.edu:8080/dspace/bitstream/2148/39/1/SpeakingHupa.pdf
So is Bigfoot one of the Hupa's "little friends" or are we to find more to the story? To do this we must find out about the Old Man of the Woods and if any traditional tales might be able to found from a time before we should expect Bigfoot contamination. It is important to note here that the Hupa are of the Athabaskan language group and thus have shared traditions and tales with other peoples in this language group.
A tale of the Old Man of the Woods comes from Pliny Earle Goddard's 1906
Journal of American Folklore, nine narratives collected in 1903 and under the heading "Lassik Tales".
She and her grandchild alone were not killed. A piece of tan oak bark had fallen over him and hidden him. The old woman made her grandchild swim. "My poor grandchild," she said. "He will grow up to avenge his grandfather."
She heard him give a shout and then he ran into the house and picked up the big knife. "What is it, my grandchild?" she asked. " 'Gun kuk, gun gun,' it said as it was jumping on a log," replied the boy. "Well done! gray squirrel it is called. People eat that kind, my grandson." Another time he gave a shout and ran in. "What is it, my grandchild?" asked the old woman. "Somebody is pawing dirt over himself," replied the boy. "Good for you, my grandchild," said his grandmother. Putting the big knife in the burden-basket he started away.
Old man of the woods, who had been setting snares during a time of low-lying fog, captured the boy and carried him off.
"Bring some water," he was commanded. "You will be killed," he heard a scalp say. He ran away over the ridge holloaing. The old man heard him and gave chase. He came to his grandmother's home. "Come in, my grandchild," she said. "Come in, my brother-in-law," she said to the old man when he appeared. "Let us gamble," she suggested to him. While they were playing, she killed him.
Source: Goddard, Pliny Earle."Lassik Tales."Journal of American Folk-Lore.. Vol. XIX, No. LXXIII, (Apr.-Jun.1906), p.133-140.
http://www.talesunlimited.com/fulltext.asp?taleid=1611&search_criteria=N0
This tale comes from the Eel River Athapaskan traditional narratives (myths, legends, tales, and oral histories) of the Pomo people of south and central California. They have important influences from the Hupa, Yurok, and Karuk.
http://en.wikipedia.org/wiki/Eel_River_Athapaskan_traditional_narratives
It doesn't seem that the Old man of the Woods strikes us as any kind of 8ft bipedal beast but rather nothing more than a type of hermit. Once again I fail to find any traditonal connection between the Hupa and Bigfoot.