The Japanese halfbeak, or sayori, is in season. Mainly caught in spring, before the spawning season, which runs from April to June, sayori (Hyporhamphus sajori) is found in the western Pacific around Japan, Taiwan and Korea. In Japan, it is mostly fished in Mie, Hyogo, Ishikawa, Hiroshima and Wakayama prefectures.
A fishmonger in the Toyo-Minami Ichiba, a public market in the Shonai neighborhood of Toyonaka City, Osaka Prefecture, said that while sayori looks similar to sanma (Pacific saury), saury is a blue fish and oily, while sayori has white flesh with a clean, light taste. This shop sourced from Awaji Island in the Seto Inland Sea.
The other noticeable differences are that the halfbeak is a brighter shade of silver, a bit thinner and longer, and with an elongated lower jaw – leading to its English name.
At this shop, with some bargaining, three fish cost 500 yen, or JPY 166 (USD 1.46, EUR 1.38) per fish. At wholesale, the five-year average price at Tokyo’s Tsukiji Wholesale Market in spring is between JPY 2,300 and 2,500 per kilogram (USD 20.26 to 22.02, EUR 19.23 to 20.89).
Monthly sales volumes of Japanese halfbeak at Tsukiji follow a steady pattern without great variation in numbers from year to year. Volumes are minimal – under five metric tons – from June to October, but then gradually rise, peaking in March or April. The five-year average volume for these two months was a little over 25 metric tons. While this shows the seasonal trend, these figures do not show the total catch, as Tsukiji is in Tokyo, while the fish is mainly caught – and probably also mostly consumed – in Western Japan, including Osaka.
The Japanese halfbeak is closely related to the ballyhoo (Hemiramphus brasiliensis), which inhabits the Atlantic Ocean and is commonly used as bait for marlin and swordfish in the U.S.A. They share the characteristic long lower jaw – or actually “chin,” since the teeth do not extend that far – of the halfbeak family.
They are both needlefish, and in the same order, “Beloniformes,” as flying fish and Pacific saury. All are medium-sized, streamlined fish that feed near the surface on algae, plankton, or smaller fish. All have the same ability of “tail-walking” on the surface of the water.
The function of the halfbeak’s elongated chin is debated. Since it feeds near the surface, it does not seem to be used for rooting about in sediment for prey. Instead it may serve to lengthen the lateral-line detection system. Fish use sensors along their sides to detect changes in pressure and vibrations, and this helps them to sense prey and to school with other fish. Lengthening the line would increase the range of detection.
But for the chef, it doesn’t matter. The head and tail are cut off as a first step in preparation. Then the fish is slit and eviscerated. A black coating on the inside of the belly must be gently brushed off, which is a bit of hassle, and may be a reason that the halfbeak is not more popular than it is. A black line, corresponding to the lateral line, will remain.
The coating, though on the upper interior, is thought to have a countershading effect – as the fish is slightly transparent against light, the shading on the upper interior makes the fish more reflective from below and less reflective from above, thus making it less visible both to other fish below and to birds above.
Continuing the preparation, the fins are removed and then, the skin, which is chewy, must be removed by first separating it from the body at the tail and then, by a rocking, prying motion with the back of the knife, gradually working up toward the front – another reason that the halfbeak is not more popular than it is.
Then, the long, striped, fillet can be cut on a bias into two or three pieces. Now, it can be served raw as sushi or sashimi, or pan-fried in olive oil.
The halfbeak is troublesome to prepare, but its clean taste and firm white meat is worth it to many seafood-lovers in Japan.
