September 6, 2019
Evidence of a Pre-Clovis site at Cooper’s Ferry Idaho has been uncovered. The dates for the evidence so far point to a 16,000 years ago settlement, Charcoal unearthed there point to a settlement date of 15,945-15,335 hearts ago. Some other bone and charcoal are dated at 14,075 and 15,195 years ago. Artifacts at the site still show up at 8000 years ago. So this site had a very long occupation. The site was probably occupied seasonally for hunting, gathering, fishing. The local Nez Perce tribe members know the site as Nipéhe.
The only way these settlers could have arrived is by foot or boat along the Pacific Coast at these dates and not across the Bering strait, which was ice covered at that time.
Animal bones and discarded stone tools, including bifaces (two-sided handaxes blades) sharp stone flakes, and fragments of two projectile points that are earlier in style than Clovis tools have been uncovered. The stemmed points are very similar to stemmed points on Hokkaido in Japan that date to 16,000-13,000 years ago. Other stone artifacts found also resemble the Hokkaido tradition.
The research is published in Science, 2019. DOI: 10.1126/science.aax9830 (About DOIs).
And Ars Technica has the synopsis here.
Although there has been no human DNA found yet, nor any evidence of more concrete human occupation like post holes, fabrics etc. The stone tools are at the same dated level as the animal bones found. And there is proof that the settlers dug hearths and pits in which the Pre-Clovis animal bones were found.
There will be debate about the stemmed points age in terms of development. Clovis points and stemmed points were in use simultaneously.
These additional facts are at Science magazine;
(My addition; without human DNA proof and human artifacts found that are not just stone tools, the proof here is not as strong as Pre-Clovis proof at Monte Verde, Chile and Paisley Cave in Oregon, but the evidence is very close to absolute proof.)
Mike Ruggeri’s Pre-Clovis Sites in the Americas