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In search of our lost salmon, Part 3

It turns out the “missing link” of the salmon run I was looking for is actually a series of kinks in the chain itself.

It turns out the “missing link” of the salmon run I was looking for is actually a series of kinks in the chain itself. The day after Christmas, Dad and I said goodbye to Uncle Mark in Boise and headed to Weiser, Idaho before sunrise. The roads were sloppy and Mark warned us of a severe weather warning, but I had to talk to Don Anderson that day because he and his wife Shelly were packing up and driving to Mexico for two months. When we arrived two hours later, the storm had passed and Don greeted us in his driveway. Shelly had coffee going, but Don was already excited to get started. I asked him to tell me how the fish populations, namely salmon, have changed over the past few decades around McCall and to give me some reasons why.

Don Anderson was the Regional Fisheries Manager for the Idaho Fish & Game until he retired in 2000, only to start working for the NOAA National Marine Fisheries Service.When it comes to fisheries, or fishing in general, Don defines them simply as “people interacting with fish”. Whether we raise them for harvesting or release them into the wild for recreational fishermen, the concept is very similar in that we should be very careful with their habitat.

Don states that dams are the major negative influence on salmon populations in the Columbia River Basin (this includes McCall). But some argue that the dams are necessary for affordable electricity, and while there have been some compromises in favor of wildlife, the Salmon stocks are not where they could be in the absence of dams. Thus the need for hatcheries and fisheries (hatcheries for releasing juveniles into the wild; fisheries for harvesting).

Out of the Endangered Species Act came two primary types of fish hatcheries: production hatcheries to mitigate the damage caused by dams, and conservation hatcheries to act as a “Noah’s Arc” for fish genetics.

At his kitchen table, Don drew a map on the back of notepaper to show me the dams along Columbia River, the Snake River that breaks off the Columbia, and the various tributaries that feed into the Snake, including the Salmon River. During the late 1800’s, the Bonneville Power Administration (BPA), along with the Army Corps of Engineers, built a series of dams leading inland up to the Salmon River. More were added in the early- to mid-1900’s, and almost all of the dams were built for hydro-electric power. Although fishermen noticed a diminished stock as the dams were built, Don says the most notable reduction occurred when the Brownlee Dam was built on the Snake River in 1958, which wiped out nearly 95% of the salmon population in the Batholith region.

Why do dams affect fish migration so negatively? Partly because the fish cannot handle the stress of swimming through or jumping over dams during migration. Partly because dams slow their trip towards saltwater. Dams are most damaging to juvenile fish, which get beat up by the pressure change as they move through the lower chamber of the dams- unless they are big enough to dive over the dam wall to splash into a drastic pressure change anyway. Juveniles are headed downstream during “smoltification”. After rearing for a year in fresh water, it’s time to move towards salt water. And as they migrate, their biochemistry adjusts at a certain rate to prepare them for saltwater. This trip, free of unnatural obstacles, would normally take 10-16 days. With dams in place, and with as many as they face on the way out of Idaho, their trip can take up to 10-12 weeks. We know that saltwater creatures cannot survive long in freshwater, but tell that to a salmon’s biochemistry which is moving at the rate that was intended. The slowed migration can lead to disease that spreads among the remaining fish who made it past the dams. (From a human perspective on stress, imagine going on a family road trip that is supposed to take two weeks, but due to forces beyond your control, the trip takes three months. I don’t think I need to get too graphic to drive home my point).

The BPA did try to mitigate the impact their dams had on the fish. They tried “barging”- floating giant barges upstream to collect juveniles and ship them downstream, but when fish are contained in the same water, close together, it’s not much different than being trapped behind a dam. Disease sets in and spreads among the stock. Once adequate filtration systems were installed it helped matters, but barging is not a sustainable means of conserving the fish populations. The BPA instead considered and attempted the spill-over method, allowing the water to remain at a level for fish to spill over the dam. But this costs the power companies money, and is still stressful on the fish.

Why not just remove the dams altogether? Although this is being done across the country for the sake of wildlife and because dams DO have a shelf life before reevaluation (about 100-150 years), there are some major players in this game that you might not be aware of. I was surprised to hear about some who have a vested interest in preserving the dam system in Idaho. Sure, hydro-electric power has created jobs, and the water flowing through Idaho has supplied power for most of the Northwestern United States. But reservoirs are not built to last forever- they age, and must be relicensed every 50 years. I thought perhaps the dams were providing irrigation for farmers in the Batholith region. Actually, Don points out, only some farms are irrigated and those are the large, corporate agribusiness operations who carry weight. “You won’t hear about Joe Farmer down the road getting any irrigation like the big guys,” Don says. Those corporate agribusinesses, along with the BPA, fight all attempts to remove the dams. Others include the Army Corps of Engineers, who helped build and partly own the dams. Don mentioned that Boeing, the aircraft manufacturer, also fights attempts to remove the dams; they need  hydroelectric power to smelt aluminum (although I found no documentation of their role during my short trip in Idaho).

In 2002, the American Fisheries Society, composed of many fish biologists, released The Ecology of Dam Removal: A Summary of Benefits and Impacts, and dedicated an entire section to the migration of fish and other organisms. Dams were named as a major impediment to salmon migration.

If not everyone can agree on removing the dams, as Don believes should be done, surely some modification to hydro-electric production is in order.

While dams may be the main reason we’ve seen a depletion in fish populations in the Idaho Batholith, Don agrees with my uncle Mark that logging has played a huge role as well. In 1964 the Idaho logging system built many roads as a means of hauling logs, but these roads were not maintained and soon eroded into the rivers. Later, forest fires decimated a large portion of trees, but that same year brought heavy rains in the spring which fell on dense snowpack. An early warming led to serious flooding and landslides, particularly in a region called Poverty Flat. The sediment build-up wiped out half of the South Fork run in the Salmon River- an area that produced half of all the salmon in the entire Columbia waterway. There is STILL sediment from that 1964 disaster stirring up in the South Fork today.

How does sediment affect salmon so negatively? When the fish lay eggs they nudge pebbles over the bed to protect the eggs and keep them weighed down. Too much sediment entombs the fish eggs, and if they do hatch they cannot swim to the surface. The decreased productivity is also impacted when juveniles can’t survive the winters because they can’t get into the loose gravel beneath the excess sediment to conserve energy prior and during migration.

Don points out that the salmon are becoming endangered, and soon the Endangered Species Act will kick in. The ESA requires that you do whatever you must do to avoid extinction. Which could very well be removing those dams, even as a last resort. He argues that the economics would rebalance if we eliminate the barge runs and some hydropower. To compensate, the rivers would be open for recreation and tourism, while replenishing the salmon stock. “Humans have done a lot to wreck natural habitats. We deserve to go extinct!” Don laughs, “But the salmon do not.”

Don’s replacement at Fish and Game, Kim Apperson, was gracious enough to give me more information on the salmon runs in the Columbia River Basin, and how dams affect migration. You can read more here and here).

In an effort to stave off extinction in Idaho, fish hatcheries (the parents with the Easter eggs in my previous post) are performing near-magical conservation feats to restore the numbers. More on that later. While visiting my Dad in McCall I stayed up late watching a Back to the Future marathon on Direct TV. Six straight hours spent in front of the TV and a crackling fire. Since I’m always on the lookout for meaningful parallels, and not wanting to feel like those six hours were wasted, I entertained the notion of going back in time to change the course of Idaho salmon history. Where would I begin, and how widespread would the effects be if kept even one dam from existing in the first place?  If BPA and the Army Corps of Engineers had a photograph of the future of salmon, and they watched it slowly fade and disappear, would they have continued their course of action? (I don’t own a television, and this is why). But if you are running out of options in any given situation don’t you sometimes wish you could wave a magic wand or turn back time?  

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