The state department of natural resources and the state parks and recreation commission have joined together in excellent cooperation in the conducting of this study along with the citizen advisory subcommittee and have joined together in cooperation with the department of fish and wildlife to accomplish other projects of multidisciplinary concern, and because it may be in the best interests of the state to continue such cooperation, the state parks and recreation commission, the department of natural resources, and the department of fish and wildlife are hereby directed to consider both short and long term objectives, the expertise of each agency's staff, and alternatives such as reasonably may be expected to safeguard the conservation area's values as described in RCW 79A.05.725 giving due regard to efficiency and economy of management: PROVIDED, That the interests conveyed to or by the state agencies identified in this section shall be managed by the department of natural resources until such time as the state parks and recreation commission or other public agency is managing public recreation areas and facilities located in such close proximity to the conservation area described in RCW 79A.05.730 so as to make combined management of those areas and facilities and transfer of management of the conservation area more efficient and economical than continued management by the department of natural resources. At that time the department of natural resources is directed to negotiate with the appropriate public agency for the transfer of those management responsibilities for the interests obtained within the conservation area under RCW 79A.05.725 through 79A.05.745: PROVIDED FURTHER, That the state agencies identified in this section may, by mutual agreement, undertake management of portions of the conservation area as they may from time to time determine in accordance with those rules and regulations established for natural area preserves under chapter 79.70 RCW, for natural and conservation areas under present WAC 352-16-020(3) and (6), and under chapter 77.12 RCW.