Shishamo ししゃも is a small salt sea fish endogenous to Hokkaido 北海道 and the name is derived from a native Ainu language meaning “willow leaf fish”. The name of this fish in Kanji 柳葉魚, is a classic example of “ateji” 当て字 in which the meaning of the kanji letter is “willow 柳”+”leaf 葉”+ “fish 魚” but there is no way to pronounce this Kanji as “shishamo”. Although you can still get true shishamo in Hokkaido, unfortunately, the vast majority of “shishamo” you buy and eat at an Izakaya nowadays is not true “shishamo” but its cousin “Karafuto Shishamo” or Capelin. (see P.S. below) That includes the one shown here which came from Canada. Although my memory of eating shishamo while bar-hopping in Susukino 薄野 is a bit foggy (whether because it was such a long time ago or because I was, in fact, bar-hopping), the shishamo tasted much better in Hokkaido. Whether it was “true” shishamo or “Karafuto shishamo” I was eating, like the rest of the memory, is somewhat unclear.
In any case, this fish is among the Izakaya favorites and the female with eggs or “Komochi Shishamo” 子持ちししゃも is much better to eat than the male fish without eggs. The eggs of this fish “Capelin roe” are often seasoned and artificially colored (wasabi flavoured etc) and served as “Masago” or sometimes “Tobiko” at a sushibar. “Tobiko” should be flying fish roe, so there are lots of substitutions and confusing naming when it comes to fish.
We get these fish frozen and I grilled them in a toaster oven unthawed and serve it with grated Daikon and soy sauce. This may not be the true “shishamo” but it goes well with a drink of sake.
P.S. Jon provided me with an eyewitness evidence that, indeed, some Izakayas serve true Hokkaido shishamo 北海道本ししゃも. I believe this is the menu from “Honoka“. This is something I can look forward to next time we visit Japan. Thank you, Jon.