MaST Center Aquarium

Located in central Puget Sound between Tacoma and Seattle, this hydrophone location lets you hear sounds made by orcas, humpbacks, and other marine life -- including fish and seals. Bigg's killer whales transit this location year round, and Southern Resident killer whales often pass by, especially in the fall when chum salmon run. You may also hear commercial ships going to and from the Port of Tacoma, powerboats using the adjacent ramp, and even SCUBA divers enjoying Redondo Beach.

The MaST Center location is hosted and maintained by the Marine Science and Technology Center, part of Highline College. Hydrophones were first deployed here in summer 2023 at a depth of 2 meters (below MLLW) and were sometimes chewed by dogs or river otters! In spring 2026 the hydrophones were moved ~30 meters further offshore to a depth of ~18 meters alongside a new underwater live web cam. Thanks to Director Rus Higley and Community Engagement Coordinator Aeriel Wauhob for their on-going support.

Status update 4/7/2026: Rus organizes a much deeper redeployment of the hydrophone alongside a new underwater webcam platform.

Previous updates: 11/10/2025: Carsen and Paul help Scott re-deploy a new Pisound to replace the corroded one, as well as two new CRT-40P hydrophones, this time on a binaural stand (with horizontal aperture of 96.5 cm, right channel oriented to the north on a bearing of 35 degrees true, and both elements at a depth of 3m below MLLW). The hydrophones have 60m cables and will be moved deeper by divers (in early 2026?). 10/18/2023: The live camera is now streaming and we plan to add the hydrophone audio to it. 9/29/23: Scott and Lon deploy a single repurposed Labcore40 hydrophone by hanging it over the side at a depth of ~1m. 7/5/23: initial deployment led by Cora Reese and Scott Veirs placed a new Aquarian A5 and old Labcore element near the base of the NW piling, but both failed within a month.

This node was funded in 2023 by Washington Department of Fish and Wildlife through The Department of Ecology’s Equipment Grant program to improve location detection of Southern Resident Killer Whales and other marine mammals during oil spills (SPPREG-2123-WaSDFW-00025). Its maintenance was similarly funded in 2024 by WDFW.