NOAA and the U.S. Navy are working to better understand underwater sound within the National Marine Sanctuary System. Humpback whales are known to occur throughout the main Hawaiian Islands and certain parts of the Papahānaumokuākea Marine National Monument (PMNM) in the Northwestern Hawaiian Islands. However, their presence in most parts of the PMNM is still poorly documented and understood. Remoteness and adverse winter ocean conditions make studying whales in this part of the archipelago challenging using conventional vessel-based survey methods. Autonomous gliders offer an opportunity to overcome traditional limitations by surveying areas of interest acoustically for the occurrence of song produced by male humpback whales during the winter breeding season. The Navy seeks proposals that employ glider technology coupled with acoustic monitoring capabilities to survey areas of interest in the PMNM. Proposals should offer the technology and logistical resources necessary to conduct acoustic glider surveys in the areas of interest and deliver the resulting acoustic data to the Navy. The Offeror may include a separate optional task to post-process and report on the data. The Naval Facilities Engineering and Expeditionary Warfare Center, is leading the solicitation process and is requesting pre-proposals for this topic. Details regarding the need topic can be viewed within Broad Agency Announcement (BAA) Solicitation # N3943019S2133 at https://www.neco.navy.mil/ or https://www.fbo.gov/. There is no specific format required for the pre-proposal, however, the information required in the pre-proposal is outlined in Appendix A of the announcement. The pre-proposal should be consolidated into one single file (pdf format) and the main text of the pre-proposal (excluding CVs) should not exceed 5 pages in length. All pre-proposals should be submitted via email to mandy.shoemaker@navy.mil. Pre-proposals for this topic will be accepted until 11:59 PM PDT on 30 April 2019. If invited, Offerors will be asked to submit a full proposal. Mandy Shoemaker Naval Facilities Engineering and Expeditionary Warfare Center