Sometimes, a Whale Dies

November 27, 2015 — Back in August, my wife and I got the call. Another dead whale had washed up on the shore nearby, and could we come and help the marine mammal research team from the California Academy of Sciences perform a necropsy?

A necropsy, in case you don’t watch TV crime dramas, is the surgical examination of a dead body. A dissection, basically. Something I hadn’t done since high school biology. And that was a frog.

My wife, a large-animal veterinarian with years of experience working with big creatures, was really who they wanted. I was an extra, even though I theoretically ran the place. I could help carry the bags. And maybe a camera.

A group of scientists and trained volunteers from the Cal Academy and the Marine Mammal Center (based in Marin County) descended on the scene. The Academy and the Marine Mammal Center have a good collaboration. When someone finds a living marine mammal in need of help, the Marine Mammal Center is in charge. When it’s dead, the Cal Academy is. Today, it was our turn. The Academy’s marine mammal expert and collections manager, Moe Flannery, was calling the shots.

This work saved whales’ lives.

Moe and others at the Cal Academy have been studying the mortality of marine mammals for many years. They have been tracking the time, location, and cause of death for marine mammals that wash up on the nearby Northern California coastline, roughly from Fort Bragg to Santa Cruz. This work helps us understand the patterns of whale mortality, and determine whether whale deaths are natural, or possibly man-made.

This is important stuff. In fact, their work has helped guide changes in policy, especially when it comes to designing the shipping lanes that go into and out of San Francisco Bay. Their research helped establish new, longer, and narrower shipping lanes that reduced the chances of ships hitting, and often killing, whales. This work saved whales’ lives.

This time it was a humpback whale. A “small” one: a young male, only about 33 feet long. It washed up in the little town of Pacifica, California, just south of San Francisco. It was the third whale to wash up on the town beach this year.

Naturally, there was a bit of scene on the beach. Locals, tourists, and camera crews were all there, asking questions. This year had seen a lot of unusual deaths of marine mammals, including extremely high losses of elephant seals, sea lions, and whales. Something was up in the ocean, and people were worried. They hoped the scientists had the answers. Of course, scientists had some answers, but even more questions.

We knew where and when the whale washed up. But the real question was why? Why did it die? Was it part of the larger pattern being seen along the California coast this year? Was this all linked to the unusually high ocean temperatures off the coast?

This year had seen a lot of unusual deaths of marine mammals, including extremely high losses of elephant seals, sea lions, and whales. Something was up in the ocean, and people were worried.

The team quickly got to work, taking measurements, photographs, and performing an external examination. They were carefully documenting everything; these records are part of a long-term database of whale mortality, and every detail mattered.

One thing that I found fascinating was how the team carefully photographed the whales tail, or fluke. Each whale has a unique fluke, and sometimes biologists can recognize an individual from the particular shape, markings, scars, and abrasions on the fluke. Think of it like a fingerprint.

We also found — er — parts of the whale along the beach. I won’t share the more gruesome images here, but several pieces of the whale’s baleen (the stuff that filter-feeding whales have around their mouth) were scattered around the body.

A lot of the work was focused on assessing the overall condition and basic anatomical measurements of the whale — length, estimated weight, approximate age, sex, and so on. This was for the long-term database. Think of it like a death certificate for whales.

The external examination was also looking for signs of trauma and external injury — something that might indicate why the whale died. One thing that was obvious: some other creatures had been feasting on the whale. A shark took a bite or two. But this didn’t kill the whale; it was already dead when the shark stopped for a snack.

Once the external exam was done and everything was documented, they started to cut. The scientists were looking to determine the cause of death, so they first looked for internal injuries — bruising, broken bones, and so on. They also looked for foreign material in the digestive tract, which might have killed the whale. Sometimes they find dead whales who swallowed massive amounts of fishing gear.

They were also taking samples, to bring back to the Cal Academy collection vaults. Tissues, organs, bones, and so on. This will become part of the permanent collection of the Academy, and be preserved for scientific study indefinitely into the future.

So, what did the exams tell us?

Well, after watching the necropsy and listening to the experts, I would say that this whale probably died from a ship strike. There was extensive internal bruising along one side of the body, which even I could see, and some other signs of trauma. That usually means one thing — a ship likely struck the whale and killed it instantly. However, the Cal Academy experts were careful to stress that it is not entirely certain. After all, the whale remains were already badly decomposed, and the internal organs were basically liquified. Being one hundred percent certain of anything is impossible in these situations. Besides, additional tests in the lab could tell us much more.

One thing I will never forget about a whale necropsy — the smell. Imagine the worst smell you have ever experienced. Now multiply that by ten. That’s just a small taste of what a dead whale smells like. It tooks days and multiple washing machine runs to get our clothes to smell normal again.

It’s nature’s perfect recipe for stink.

Of course, that’s not surprising. When a whale dies (assuming, for the moment, it was a ship strike), it first sinks deep into the ocean water column, and stays there for a day or two. But as the whale decomposes, gasses build up inside the body, causing it to become buoyant, and eventually float to the surface, where it cooks in the sun for a few days. Then, after that, it washes up on a beach somewhere, again sitting in the hot sun, decomposing further.

It’s nature’s perfect recipe for stink. I’ll remember that smell for the rest of my life.

You may wonder why anyone in their right mind would spend their day — especially as an unpaid volunteer — dissecting a decomposing whale. After all, it’s not the most pleasant experience. The stink alone makes this a fairly traumatic experience.

One word: Love.

Everyone there was fiercely dedicated to protecting the natural world, and whales in particular. While dissecting a dead whale was gruesome, these people knew that it may ultimately help us understand how to protect these seafaring giants, which made everything worth it. Even the stink. It was honorable work.

I know that I came away from this experience forever changed. I’ll never think of whales, ships, or the fate of the ocean the same way again.

I was especially moved by a pod of dolphins swimming just offshore, as if they were saying farewell to a fallen comrade.

A final observation: While we were working on the whale, we would sometimes look up to see other creatures swimming by. I was especially moved by a pod of dolphins swimming just offshore, as if they were saying farewell to a fallen comrade.

As we started packing up, heading back to San Francisco, I stopped to reflect on what I had seen that day. While I appreciated the science that we were doing, and the improvements in policy and conservation practice it might lead to, I couldn’t shake the feeling that I just had a deeply moving, almost spiritual, experience.

It was the same kind of feeling I would get when looking up at the arc of the Milky Way under dark skies, or a beautiful sunset over the ocean. It was magic. And, more importantly, it was a strong reminder that we all share a magnificent, beautiful planet, full of wonderous and amazing creatures — including these magnificient animals that we share a kinship to.

It was hard to leave.

Post-Script: Another Cal Academy whale expert, Sue Pemberton, just gave me an update on this whale: “…Turns out that there was a little more to this story as the lab results came in. This whale had very high levels of Domoic acid in his system, most likely from feeding on the bait fish that kept the Humpbacks around all summer. We know next-to-nothing about how much a whale can tolerate this neurotoxic diatom, so researching and documenting these occurrences helps fill in some scientific gaps. DA has been problematic for marine mammals since the first big outbreak in 1998, and now it’s a problem for people, too.”