Yes. Leasehold interests are capable of being mortgaged. In its Land Code, a First Nation may allow leasehold interests on First Nation land to be subject to mortgages and seizure by third parties.
A First Nation may also allow any certificates of possession held by members to be mortgaged to the First Nation itself or to other members.
In the event of the default on a leasehold mortgage, the First Nation has first right to redeem the mortgage.