The Tale of an Entangled Humpback Whale
Sometimes your day doesn’t go as planned. Our goal for the day was to study the bottlenose dolphins that are often seen sharing the waves with San Diego surfers. Little did we know that we’d spend most of our day with an entangled humpback whale.
A Mysterious Boater Wave
We launched our boat, loaded our cameras and other research equipment, and the uncrewed aerial system (also known as a drone) team headed out to the coastal study area. Along our way, we saw the familiar “boater wave” from passengers aboard a whale watching vessel. In response, we waved back and continued on our course. The boater wave is a time-honored maritime tradition of acknowledging each other and relaying the unspoken message that mariners always have one another's back. As we passed, their waving got faster and faster, interspersed with some gestures that made us think of swimming sea animals. I said to our team, “Wow, they are very enthusiastic!” Just then, we realized that the whale watching vessel was heading towards us, with what must have been every single passenger on board standing on the bow, gesturing with their arms to come towards them. So, we slowed our boat and came to a full stop to see what was going on.
Spotted: An Entangled Humpback
The whale watchers were trying to get our attention for good reason–they had spotted an entangled humpback whale. When they noticed the NOAA logo on our vessel, they were hopeful that we could take over tracking the whale until a disentanglement team arrived to help. “What’s your plan for the day?” they asked. “Well, it looks like our plans have changed,” I replied over the radio.
For the next five hours, we documented the entanglement and tracked the whale’s location, speed, course, dive times, and behavior to relay to the disentanglement team, who soon arrived on the scene. Aside from the gear entangling the whale, all of the behavioral measures we recorded seemed fairly normal for a humpback whale in transit. The whale traveled consistently southward at approximately 2.5 knots (3 miles per hour), surfacing 2 to 3 times before each dive, with each lasting approximately six minutes. When the whale surfaced to breathe, we used hand-held cameras to take pictures of the dorsal fin, flank (its side) and flukes to help identify the individual whale and launched the drone to document the extent of the entanglement and type of gear.
Decisions on Disentanglement
Our aerial video footage combined with underwater video taken by the SeaWorld San Diego disentanglement team showed that a gillnet was wrapped around the mouth of the whale, under the body and around the flipper. To remove this type of entanglement from the whale would be too dangerous for the team due to the close approach needed toward the whale's head. The disentanglement team made the difficult decision to stand down and cancel any attempt of disentanglement.
Unfortunately, in this case there was nothing more that we could do. This type of situation always weighs heavily on all team members. But at the end of the day, we need to make sure that we all come home safely to our families and are available to help the next whale when it is feasible. We took one last look at the whale as it took a dive and then headed for home. While our days don’t always go as planned or end the way we want them to, we do the best that we can. The knowledge, experience, and documentation we gain from each entanglement response goes towards improving the outcome for future whales or perhaps even this same whale.
How You Can Help
If you see an entangled whale, call 1-877-SOS-WHALe. Stand by if you can, but don’t try to disentangle the whale yourself - let qualified experts respond.
For more information on NOAA’s entanglement response program: