Wasn't Bigfoot a fan of horse tail plaiting?
It's not clear when - or with what evidence - mane braiding / plaiting became associated with Bigfoot / Sasquatch in North America.
There's a South American wild hairy dwarf being called a
duende that's reputed to braid horse's manes so as to improvise stirrups, and lore about the duende supposedly dates back a long way.
The earliest documented mention of Bigfoot and mane braiding I've found is in Lisa Shiel's 2006 book
Backyard Bigfoot:
https://books.google.com/books?id=ybXgAAAACAAJ&q=braid#v=onepage&q=braid&f=false
... in which she describes 2005 incidents involving her own horse(s).
The earliest reference I've found to a big relict hominin braiding / plaiting horses' manes is in relation to the almasty / almas in central and western Eurasia.
This archived 2011 edition of a yeti / almasty reports webpage from a defunct website:
https://web.archive.org/web/20110303060841/http://www.stgr-primates.de/reports.html
... mentions two sightings of an almasty apparently braiding a horse's mane.
One is a report from a Kabardinian man named Mukhadin Kliynshev, who claimed to have witnessed such a thing in 1978.
The other (and most often cited one ... ) is the sighting by cryptozoologist Gregory Panchenko in the same area in 1991.
I wonder whether (a) mane braiding has a history in North American relict hominin lore farther back than 2006 or (b) Shiel - or perhaps other North American Bigfoot / Sasquatch investigators - adopted the idea from either South American folklore or Eurasian almasty reports.