After a two-day search, marine biologists on Saturday, April 14, located a gray whale moving through Puget Sound that had been spotted the day before entangled in fishing gear. Due to an unusual turn of events, however, it was lost again.

The NOAA’s fisheries division is now seeking the help of boaters, whale watchers or others in finding the whale, who is not believed to a regular visitor to the area, so its health and condition can be assessed, according to the Seattle Times.

Scientists with Sealife Response, Rehab, Research (SR3) and the Cascadia Research Collective (CRC) worked together to track the whale. SR3’s Doug Sandilands, who shared this footage with Storyful, and said the stainless steel “grapple” thrown at the start of the video was used to grab onto the entangling gear, allowing them to turn off the engine of their inflatable boat and be dragged along behind the whale, as the footage shows. They then used an underwater camera to assess how the whale was entangled.

The scientists eventually found the whale on Saturday evening, after being hindered by bad weather the day before, and attached a satellite-tracking device and a buoy to it, the Seattle Times reported. As the sun went down, the rescue effort was suspended and those involved assumed the tracking device would allow them to track the whale the next day to continue untangling the whale from the fishing gear. However, the signals from the device stopped overnight and were later picked up from a location on land, the report said. A yacht owner later told scientists he saw the whale swim under his boat, leading them to believe the tracking device became dislodged as the whale rubbed against the boat, according to the Seattle Times. Credit: SR3 and CRC via Storyful