North Pacific Crestfish

North Pacific Crestfish
When Taku Suganuma hauled up his fixed fishing net off the coast of Imizu, he made a catch of the day that he had never seen before.

The strange fish had a unique face with a protruding head, rippling its dorsal fin and shaking its 1-meter-long silver body.

Suganuma, 24, caught the fish on the Shintokumaru fishing boat, which sails out of Imizu, in the early hours of May 15, when the firefly squid fishing season was coming to an end.

At first, he thought it was a lowsail ribbonfish, which is often caught in nets during this season. However, a younger colleague knowledgeable about fish species said it might be a deep-sea North Pacific crestfish, aka unicornfish.

Suganuma decided to give the fish to the Uozu Aquarium because of its rarity.

A North Pacific crestfish hauled onto a fishing boat in Toyama Bay off the coast of Imizu, Toyama Prefecture, on May 15
© Taku Suganuma
A North Pacific crestfish hauled onto a fishing boat in Toyama Bay off the coast of Imizu, Toyama Prefecture, on May 15
According to records kept by the aquarium, a North Pacific crestfish hadn't been spotted in Toyama Prefecture for more than 30 years since one was found washed up at the mouth of the Katakaigawa river in Uozu in 1988. However, eight of the unicornfish either were caught or were snared in nets between February and April last year.

The North Pacific crestfish is characterized by a red dorsal fin and releases black ink from its anus in response when it senses danger.

It is believed that the fish lives in the intermediate layer at depths between 200 and 1,000 meters offshore, but details about its life remain unknown because it is rarely caught.

Specimens usually quickly die due to differences in the water temperature and other factors when brought to the surface. Only one of the eight fish taken to the aquarium remained alive for about an hour.

It released a large amount of ink several times as it swam around in a large tank containing 16 tons of seawater, instantly limiting visibility to only 10 centimeters ahead.

Tomoharu Kimura, a breeder and researcher at the aquarium, said that the white flesh of the fish is crunchy like flounder when served as sashimi, while it tastes bland and plain.

A close look at the contents of its stomach provided hints of the North Pacific crestfish's life and ecosystem, as well as a threat to marine life: plastic waste.

(Read more here)