Fish born in the river swim downstream to the salt waters of the North Pacific. They spend three to five years in the ocean, then make a difficult journey back upriver to spawn.
(Related video: "Salmon Brave Bears in Alaska Summer Spawn.")
The exact dates of the festival are different each year depending on the start of the salmon migration. Events usually take place in late October or early November.
Yet in the midst of what amounts to a yearly party celebrating wild salmon, few people realize that the guests of honor are becoming increasingly rare in this region.
During the first Yangyang Salmon Festival, the number of salmon returning to the river peaked at over 200,000. But in 2000 the numbers crashed to 17,000.
(Related news: "Seafood May Be Gone by 2048, Study Says" [November 2, 2006].)
Reasons for the low return rate in 2000 are not clear, but experts say declining habitat could be a major factor.
A hundred yards (91 meters) from the festival grounds a new bridge is under construction, and the work creates a quagmire of silted water and mud.
Such development also affects water temperatures, which in turn affects the fish.
"Salmon need cold water," said Nam Kyoung-sook of Green Korea, one of the country's leading environmental organizations.
"On the Namdae the water temperature has increased because of road-building, which leads to deforestation and then siltation, and that means the salmon won't return."
What's more, the treeless riverbanks are lined with cement blocks and are devoid of wetland buffer zones that would naturally filter out silt and pollutants entering the river due to human activities.
Farther upstream numerous weirs and dams are in place to help prevent floods.
While these structures do have concrete fish passages, a prolonged drought earlier this autumn lowered the water levels to a mere trickle.
Chum salmon are the weakest leapers of Pacific salmon and can be easily halted by such obstacles, according to the Canadian Department of Fisheries and Oceans.
Helping Hands
But at least one building downstream of the festival grounds is part of a dedicated effort to boost salmon numbers in the Namdae.
The Salmon Research Center of the East Sea Fisheries Research Institute in Yangyang forms an artificial embankment on the river.
The barrier funnels salmon into the river's main channel, which is blocked with netting and leads to the edge of the hatchery grounds, where the fish are captured.
Here the dorsal fins of hundreds of salmon cut the water's surface like those of tiny cruising sharks.
The center's main mission is to catch adult chum salmon and strip their eggs and sperm for artificial reproduction.
"So far we have caught 600 salmon, and we have been netting them since October 11 and will continue until November 30," said Lee Chae-sung, head of the Salmon Research Center.
"Our goal is to catch 9,500 salmon for broodstock."
The center releases smolts—salmon about two years old that are ready to migrate out to sea—each March into the Namdae and 17 streams around the country.
According to Lee, "artificial fertilization gives better chances for reproduction."
Nam, of Green Korea, said that the program "is a realistic choice, but for now it is more important to protect the salmon habitat. If that isn't healthy, the salmon won't survive."
Free Email News Updates
Best Online Newsletter, 2006 Codie Awards
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).
|
SOURCES AND RELATED WEB SITES
|
