A trustee need not provide bond to secure performance of the trustee's duties unless required by the terms of the trust, reasonably requested by a beneficiary, or found by the court to be necessary to protect the interests of the beneficiaries who are not able to protect themselves and whose interests otherwise are not adequately represented. On petition of the trustee or other interested person, the court may excuse a requirement of bond, reduce the amount of the bond, release the surety, or permit the substitution of another bond with the same or different sureties. If bond is required, it shall be filed in the court of registration or other appropriate court in amounts and with sureties and liabilities as provided in AS 13.16.260 and 13.16.270 relating to bonds of personal representatives.