Your right the DOW gets no funding from the Feds but is a bureau in the Department of Interior. It relies entirely for its funding from the sale of tags, licences, and a fed. excise tax on hunting and fishing gear. So I guess you could say that a hunting lic. fee is 100% tax, or you could say it's a donation (fee) to a Goverment agency to protect your right to hunt and fish. I feel better thinking of it as a donation (fee) although the definition of a tax is an "enforced contribution to a Government entity". So I guess that could go either way depending on how you want to look at it. Good one.
P.S. The Government loves to call some taxes a fee. I guess to make us feel better.