The scenic cruise in the northern part of Lake Biwa

Today, I would like to talk about Lake Biwa and fisherman's work that I experienced the other day.  Lake Biwa is located in Shiga Prefecture, Japan and needless to say the Japan's largest lake and it has the area about 670 square kilo meters.   The northern part of Lake Biwa is still rich in nature, but its southern part has been developed and densely populated.

 Actually, I found the interesting information on the PR brochure of Nagahama City; it was the cruise of the northern Lake Biwa by boarding on fisherman's boats. So, I booked immediately.

This is the fishing port that we will depart from by fisherman's boats, though it might be a bit run-down, but the weather is very nice.

Approximately 30 participants boarded in three separate boats and headed for the fishing area. At first, three boats proceeded north for a while in order to show us the historical tunnel that was dug by hand during the Edo period (over 200 years ago) for flood prevention works. Next, fishermen pumped up the deep water under over 15 m and surface water, poured them in buckets. Then, they encouraged us to compare the water temperature by dipping our hands.

Fishermen explained how cool the deep water was compared with surface water and told that fishes are existing in this deep area.

After that, we headed toward the destination. In the distance, we can see Chikubu-shima Island. It is the most popular sightseeing spot in Lake Biwa. But the waves were a little high today, so, for safety reasons, we did not approach the island.

By the way, here's a short YouTube video on a fisherman's boat proceeding at the max cruising speed. Please press the play button if you get curious.

We've arrived at the fishing site where the gill nets were set up since last night.

Chief fisherman was pulling up the gill net, while another fisherman tried to bundle together the net that was already pulled up using a long pole.

Since the mesh size of this gill net is wide, small fishes can pass through, but bigger fishes are caught up. 

These fishes are today's catch.

The child participators were removing fishes from the net. I also tried to do the same, but it was troublesome, so I gave up soon.

This is the notorious invasive fish known as the bluegill. It has sharp dorsal fins. It is a very harmful fish that preys on the eggs and young fishes of crucian carp and ayu (sweetfish) and designated as invasive alien species by the government. 

Recently, its numbers have been declining in Lake Biwa thanks to the efforts of fishermen to eradicate it. The edge of its gill cover is dark blue, which is where it gets its name from. (Please take a look at below photo.)  The staff of the prefectural fisheries department explained the characteristic of each fish and the current state of fisheries.

This is the nigoro-buna, the specific crucian carp that is the endemic species of Lake Biwa. It is used as the raw material for Lake Biwa's speciality cuisine, funa-zushi. 

Usually, funa-zushi sold in a market is made of a fish of this size.

For your information, funa-zushi, a local specialty of Shiga Prefecture, is a kind of fermented food that is salt-preserved fish and rice that are pickled together. It is said that nigoro-buna is most suitable for funa-zushi.  But due to the strong sour taste and odor caused by lactic acid fermentation, funa-zushi  may not be for everyone.

This is the funa-zushi made of a nigoro-buna. Usually, funa-zushi  is served in thin slices.  What looks dark orange is the eggs of a female nigoro-buna. Female individuals during spawning season (with lots of eggs) are particularly prized. Such funa-zushi  like this is a popular dish for festive occasions such as New Year. It is renowned as a luxury snack to accompany alcoholic drinks. Incidentally, the white mass is fermented rice. I think it can be eaten but too salty. You don't have to force yourself to eat.

 

This is a large Nigoro-buna. I saw that two or three Nigoro-buna of this size were caught in a gill net. The staff mentioned above said that it would take about three years if we made this into funa-zushi, I think probably it would take a long time until the hard bones soften due to lactic acid fermentation. Usually, it takes a half year until it can be eaten.

Ayu and Gin-buna were also trapped in the net. Gin-buna is a different crucian carp and it can be distinguished from the Nigoro-buna by a head shape. 

Comparison of the Nigoro-buna of two sizes. A funa-zushi made of such a large crucian carp must be really delicious. I guarantee.

This is an Ayu, but I think it's smaller than those caught in rivers. Some Ayu living in Lake Biwa do not swim upstream, from the Lake to rivers, remaining in the lake. These Ayu cannot grow large. On the other hand, the Ayu that moved into the river can eat enough moss that are growing on stones and can grow larger.

Today's lunch: fresh Ayu tempura (below left), Tsukudani made of small Ayu (Ayu boiled in soy sauce and other seasonings), and Ebi-mame (A local dish made by simmering soybeans together with river shrimps from Lake Biwa seasoned sweety and spicy). These are the famous local cuisines of Shiga Prefecture.

July 26th, 2025