Cormorant Sushi
As photographer James Kusz’s video demonstrates, this Double-crested Cormorant off the north coast of the park had no difficulty in swallowing the whole sculpin fish it had captured, even though the fish looked thicker than the bird’s bill and neck. The cormorant, like many other fish-eating birds and some land animals, can unhinge its jaws, and obviously it can expand its neck, and its neck muscles can propel its catch down to its gut in the blink of an eye.
The cormorant’s ability to handle bigger fish is the basis for the ancient practice the Japanese call ukai, which means fishermen using trained cormorants to catch fish for them. The men tie a noose or a ring around the base of the bird’s neck so that the bird can swallow a big fish into its neck, but no further. The fishermen then bring the bird to their boat and get the bird to cough up the fish. How they do that, my sources don’t describe. The practice of cormorant fishing is said to be ancient in Japan, China, Greece, and Peru. Formerly of economic importance, it’s today done mainly as a tourist attraction.
On the subject of cormorants, the American Ornithological Society’s Committee on Classification and Nomenclature of North and Middle American Birds this week issued its annual supplement containing revisions to the official bird list. So far as I could see from a summary article, none of the racist, colonialist, patriarchal or generally person-linked bird names has been modified, although a revision has been promised for the (hopefully not distant) future. Of practical concern for our birds in the park is that the cormorant group has been split. Formerly all classed in the genus Phalacrorax, the Double-crested Cormorant is now put into the new Nannopterum genus, and its close relative also seen here, the Pelagic Cormorant, is now in a different genus, the Urile. Thanks to Maureen Lahiff for forwarding the article.
For another view of a Nannopterum auritum swallowing a big fish, see “Cormorant Bags Big Fish and Celebrates,” Jan. 31 2017.
More about them: Wikipedia Cornell Audubon In Chavez Park
You can stop-motion each of these videos, https://www.google.com/search?client=ubuntu&hs=uzJ&channel=fs&tbm=vid&q=ukai+cormorant+fishing&sa=X&ved=2ahUKEwjDzKv9tM3xAhXCtp4KHc3QA5cQ8ccDegQIBBAL, at the points where they grab the cormorants from the water and extract the fish.
There are generally 3-4 frames in each extraction that show the technique; collectively, you can get the whole process revealed in more fine-grained detail.
Essentially, they grab them by the neck with one hand, with the pinky side of the hand toward the body and the hand positioned below the fish, and hold the head under the mandible with the other hand, holding the mandible open to direct the fish as it comes out. They seem to squeeze / close their fingers up the neck toward the mouth to work the fish up the neck and into the mouth.