When an angler casts bait, it normally is to entice fish into striking it as food. Not so when ayu fishing. Here the lure resembles another ayu, and the live fish only wants to drive the intruder away.
Ayu is a smeltlike relative of trout found in streams across the Japan archipelago, where they are considered a symbol of the countryside and being at one with nature. The young migrate to sea and return in March to ascend coastal waters.
They are short-lived, surviving for only about twelve months, and thus are known as nen-gyo, or “year-fish“. It is said that the Japanese people feel sorry for them because of their brief existence. Revered for their aromatic flavor, they are also called “sweetfish” and the “queen of freshwater streams.”
Ayu are difficult to catch by the usual angling methods, because they feed by scraping algae off rocks with their saw-shaped teeth. But the ayu has a behavioral trait that renders it vulnerable to anglers:
It claims its own “turf“, attacking and driving away any other ayu that tries to invade it. A single ayu’s territory measures about one hundred to two hundred square feet.
Near Kyoto some three hundred years ago, anglers learned to take advantage of this territorial behavior with a live-lure technique called tomo-zuri. In this method, the fishermen ties a live ayu to a line by its gills, fits it with three or four special hooks along its underside, and then guides this “baitfish” with a very long rod (as long as thirty to thirty-three feet) into the lair of another.
The owner of the territory will keep its eyes on the interloper and, when it becomes apparent that the intruder is not leaving, will attack it by ramming its belly, thereby getting hooked, usually a little behind the head.
When the tethered baitfish eventually becomes exhausted, the angler replaces it with a freshly cause ayu. Fine lines are used to avoid tiring an ayu quickly; modern technology has produced metal threads for this purpose as thin as forty microns in diameter.
Because of their great length, lightweight rods are most appreciated; the very lightest can cost as much as $5,000.
In earlier centuries, ayu were accepted in Japan as payment for taxes. Today ayu is associated with summer in that nation in the same way that grilled hot dogs and hamburgers are in the United States.
The fish is impaled headfirst on a stick, salted, and cooked over hot coals. Unfortunately, dams have diminished ayu runs. But public realization of the decline in population of this cultural icon has led to greater environmental awareness in Japan.