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(This post was originally published September 30, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

Part of the reason so little is known about the 23 recognized species of beaked whales is because they are so skittish at the surface. Vessels rarely approach within a few hundred meters before the whales slip under the waves, never to be seen again. Depending on the species, individual beaked whales can weigh anywhere from 1 to 12 tons, leaving them with seemingly little to fear in the ocean, but killer whales are nevertheless known to prey on them. Not surprisingly, beaked whales have evolved various behaviors that help them minimize contact with killer whales.

As deep divers — some to almost 3000 meters — beaked whales use echolocation to detect their prey (mainly squid and fish). Although beaked whales can out-dive them, killer whales have the benefit of superior hearing abilities. Consequently, when beaked whales surface to breathe, they quit vocalizing several minutes and several hundred meters below the surface. Then instead of coming straight up, they veer off in random directions to avoid detection by eavesdropping killer whales. At the surface, the beaked whales take a few quick gulps of air and then descend to several hundred meters for 10 minutes or more, before surfacing again. They do a series of these relatively shallow breathing dives before they make their deep foraging dive — the less time they spend at the surface and the less noise they make there, the less likely they are to attract bad company.

Beaked whales also have some physical features that make them harder to capture. Their pectoral flippers tuck into “pockets,” making them flush with the body and difficult for a killer whale to bite onto. The dorsal fin, instead of being mid-body like fast-swimming dolphins, is positioned back toward the flukes so that when the tail is pumping up and down, it is also going to be very difficult for a killer whale to grab ahold of.

At 35 feet in length, Baird’s beaked whale (Berardius bairdii) is the largest species of beaked whale, but it is still vulnerable to attacks by packs of killer whales. The photo above shows one of the Baird’s beaked whales that we encountered near Heceta Bank, Oregon; the enlargement reveals tooth rake scars on its dorsal fin left by an attacking killer whale. This whale got away, but Baird’s beaked whales often have killer whale tooth rake marks on them, and it can be assumed that others aren’t so lucky. Little wonder they are wary of their time spent at the surface.

~Bob Pitman

(This post was originally published October 6, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

Maps of beaked whale distribution are usually filled with question marks — often more question marks than confirmed sighting locations. These are not small animals (imagine a dolphin that weighs as much as a Clydesdale horse), so what is the problem?

Beaked whales are incredibly difficult to see. They spend mere minutes at the surface and then can disappear for an hour or more. They typically occur in small groups. They become almost invisible in rough seas. And the diagnostic characteristic used to visually identify them to species — the location, size, and shape of teeth in the lower jaw — can only be used for males.

Imagine if we could detect them in any sea conditions and identify them to species just by listening for their distinctive echolocation signals. Our expedition has brought us one step closer to making that hope a reality.

On September 22, Annamaria was monitoring the sounds coming in from our hydrophone towed behind Pacific Storm. Software was translating the inaudible, ultrasonic signals into visual representations, and her computer screen showed a type of beaked whale signal she had never seen before. When, after just three minutes, the mystery whales stopped vocalizing, she knew they would soon be surfacing, so she directed the vessel toward where she thought they were. Despite high winds and heavy seas, making for poor sighting conditions, all aboard were called to join the search with the faint hope of finding the whales before their next dive. After 80 minutes of searching, the two whales found us! They repeatedly approached our research vessel during the next 40 minutes, allowing us to take thousands of photographs and video recordings!

Amazingly, despite these close looks, we were unable to identify them to species (once again highlighting how little we know about this group of whales)! But our expedition team does not give up easily. Standing on the bow with crossbow in hand, Bob took aim and fired a two foot-long, lightweight dart at one of the whales. It bounced off the back and landed in the water, floating with the definitive prize: a pencil eraser–sized piece of skin and blubber of our mystery whale caught in the dart tip! This biopsy sample held the key to this species identification in the DNA the tissue contained!

But the tension would not be relieved until that sample was safely aboard. Two oranges offered up by our cook were thrown to help us keep the floating dart in view while we retrieved our hydrophone (requiring 20 minutes of hand-hauling in heavy seas with the vessel in full stop as the dart and oranges slowly drifted farther and farther away). Pressure mounted as Yogi expertly maneuvered our vessel alongside the bobbing dart. Craig dipped a salmon net into the water and landed our prize on the deck as we all cheered. We had achieved a mystery beaked whale trifecta: acoustic recordings, photographs, and a biopsy sample!

Watch this space for the DNA results!

~Jay Barlow