June 06, 13 | Shizuko Kosuna
"Salmon - From birth to departure." - The first entry in our series on "Sake" (or Salmon in English).
Although southern Japan has switched into their cooler clothes, here in Hokkaido we've just barely broken into the warm season.
In forests and rivers across the island, birds and bugs are buzzing about ready to take full advantage of the hot summer season.
If you happen to take a closer look at the rivers you'll notice that they are preparing for summer in their own way.
Salmon ("Sake" in Japanese) born in the winter months have grown significantly and are now ready to set out on their own.
But just how have they spent their time in the river between birth and their departure for the ocean?
Well today I'd like to give you a glimpse of the life of a young salmon between the winter and early spring periods!
During February, when the river is covered in ice, many of the creatures in the area are busy hibernating. It is during this chilled silence that the many baby salmon spring into life.
Still just larval fish, they quickly seek out a warm patch of spring water to rest in.
While sitting in the safety of their warm water patch, the fish consume nutrients left in their stomachs by their parents. They will spend about 60 days slowly growing.
In early April many of the creatures that have been hibernating for the winter begin to wake up.
Our young fish finally have the energy to emerge from the bottom of the riverbed and search out their own food. While dining on bug larvae the fish begin to group together and make their way upstream.
At first glance it may look like a peaceful group, but don't be fooled. Competition for food and for territory is fierce and those who don't get enough to eat will end up dying before very long.
The young salmon have grown to about five centimeters in length and their bodies have turned a silvery color. Even though they are still small they set off on their long journey to the ocean.
The thaw in early May.
As they make their way upstream the fish stop occasionally for a rest in the hot sun, causing them to drift downstream while they rest.
Their time spent lazing in the sun gives the river a calm, relaxed atmosphere.
For many waterfowl and larger fish, the small salmon look like a tasty meal, and indeed the little fish face many dangers.
When the fish sense danger they use fallen logs or other small spaces as hiding places, if they can make it through all these trials they will eventually reach the ocean.
After entering the ocean the fish spend time growing up along the coast, finding larger food there.
In the summer they leave Japan and migrate out into the Pacific Ocean, returning to their birth place only after three to five years have passed.
After spending time in the rough seas, the salmon eventually grow to the imposing size of 70 centimeters before returning home. They no longer resemble the cute little fish they once were in any way.
Once they return home in the fall they get to work on spawning and fertilizing eggs. That, however, is another ordeal with many challenges which we will cover in another article. So until then, if you happen to pass a river, try to spot the young salmon on their way to the ocean!
(Hokkaido Likers Writer - Kosuna Shizuko)
Photographs and ecological commentary by Misawa Katsuya.