The appeal must be signed by the individual. While these papers normally will constitute the entire Record on Appeal, the Director may add additional information, from sources other than the individual, where necessary to facilitate a final determination. Any such additional information added to the record shall promptly be disclosed to the individual to the greatest extent possible, and an opportunity for comment thereon shall be afforded prior to the final determination. Appeals should be submitted to the Director within 90 days after the date of the initial denial.
50 C.F.R. §501.8