In search of our lost salmon, Part 4

In search of our lost salmon, Part 4

Okay, so they’re not actual magicians with magic wands, or mad scientists with a tricked-out Delorean. But I did walk away from the McCall Fish Hatchery with as many questions as I had walking in.

 I was about 10 the last time I came to the McCall fish hatchery. I came with my granddad, my twin sister, and my cousin Tom. I recall the most fascinating part, for me, was on the way out of the hatchery when I found a shiny new quarter on the concrete steps. I did not possess the level of respect for fish that I do now. Twenty years later, the hatchery is still going strong and I got a private afternoon tour. The managers had to spend all morning shoveling through a heavy snowstorm; the visitor center is buried and closed for the time being but the outdoor rearing ponds are visible from the parking lot.

The McCall Summer Chinook Hatchery was built in 1979 by the Army Corps of Engineers, and is federally funded under the Lower Snake Compensation Plan, but it is state-operated. McCall was the first Anadramous Fish Hatchery (fresh water to sea and back again to spawn), and raises 1.1 million “smolts” per year. This is considered a small amount, compared to the Rapid River Hatchery located 30 miles north in Riggins, which raises 3 million summer Chinook salmon each year.  Unlike many hatcheries that release juvenile stock directly into the source, McCall’s fish hatchery releases them into the South Fork of the Salmon River, where they are imprinted as they make their way downriver. The McCall hatchery employs 3 full time employees (General Manager, Assistant Manager, and Fish Culturist) and six to eight temps during the summer. There is a satellite trapping station about 50 miles away near Cabin Creek, but it is inaccessible during winter months (McCall receives the most snow in Idaho each year). I met with the Joel, the assistant manager, for a tour.

Joel has been with the hatchery for almost 17 years. He’s originally from Michigan, but came to Idaho after graduating because a friend at school worked with the hatchery over the summer. Joel has been here for so long, and has given tours to so many schoolkids and campkids, he speaks swiftly and only paused to sip coffee his wife brought to him.

The tour began with the indoor rearing tanks, also known as the nursery. A giant warehouse has about 12 long holding tanks, each about one meter in width. In June the river traps go into operation to collect eggs and returning, full grown salmon. All fish carcasses are returned to the river to supply nutrients so the next brood year will benefit. The eggs are incubated in trays throughout the larval stages, until they are ready to be moved to a holding tank. Traps operate through mid-August, and as the fish spawn the hatchery collects eggs twice a week. There are typically 6-8 spawnings, and the collections wrap up in September. The fish stay indoors until the following June when they are moved to the outdoor rearing tanks (two rectangular pools partially covered by an overhang to keep the water temperature low).

From the nursery to the outdoor rearing tanks, the salmon are fed low-phosphorous fishmeal made of ground-up sardines or leftover fish from a commercial ocean harvest. McCall uses a variety of feed that includes a vitamin pack, but Joel says they have not needed to use antibiotics in six or seven years. He believes this is due to the clean water source of the Payette River (where the McCall Water Treatment Plant used to discharge, but no longer does). The nursery tanks are lit with lighting systems that dim to match daylight hours and mimic nature as much as possible. When the juveniles are moved from the nursery to the outdoor rearing ponds in June, they stay there until late March when they are gathered into an oxygen-filtered truck tank and delivered to the South Fork of the Salmon River. Joel expects to move about half a million smolts in March (a smolt measures about 5 inches long), although the number of fish on premises, at capacity, is 1.1 million. The hatchery has maintained capacity for the past three years. The entire process from incubation to release take a year and a half. The salmon in the outdoor rearing ponds today are from the June 2009 brood stock.

How does the hatchery track which fish are theirs, and how many return after a year at sea? The process looks much like our migration through airport security. Before the salmon are moved from the nursery to the outdoor ponds, they are “marked” or “fin-clipped”. The Adipose fin along their back is cut, which lets recreational fishermen know they are allowed to keep those catches. Un-marked Chinooks are wild and must be thrown back. In addition to marking their stock, the hatchery will select 50,000 (out of the 1.1 million fish) and PIT tag them. PIT (Passive Integrative Transponder) tags are similar to what people use for their pets. The tags are scanned with detection devices at the dams, as a means of counting the number of hatchery population that gets past the dams, and when. The tags are loaded with the fish brood year, harvest information, and hatchery identification to help gather statistics each year as fish migrate along the 720 river miles to or from the ocean. Between dams, there are in-stream detection devices along the bottom of the rivers, as well as in the ladder system that the McCall hatchery uses for their traps. If marking and PIT-tagging doesn’t seem sufficient, another portion of the hatchery population are wire-tagged in their snouts. The tags contain an alphanumeric code that can be detected with a metal wand waved over a pond, trap, or individual fish. This extensive tracking system came out of the U.S./Canada Agreement (Pacific Salmon Treaty) in 1999 for the mutual interest in preventing over-fishing.

To give you an idea of how much of the local waterways depend on the McCall hatchery for fish, I asked what would happen if the hatchery were to stop supplementing the wild stock. Joel said, “All of the fisheries in the area would close, including the tribal fisheries just north like the Nez Perce fishery- the only local fishery that could be considered commercial, since they are allowed to sell their fish for profit”. Subsistence fishers would likely suffer as well, most of whom live in one of the poorest counties in Idaho. If it’s any indication as to how destitute this region is, Idaho Fish and Game officials are considering new rules for a bill that would allow the public to “salvage” roadkill for personal and commercial use.

“’Bout time,” Dad says, “’Conomy’s rough”. Without the hatchery, salmon returns would dwindle, Joel was sure, but he wasn’t certain about the effects on wild stock population changes if they stopped running the hatchery. “It’s difficult to say exactly. There would be some impact because the two populations are in competition to a degree.” But Joel is optimistic that the new “integrated brood stock” would solve many of the wild stock population problems.

Integrated Brood Stock? Here’s where the “Do you want salmon or not” argument comes in. In 2008, the U.S. vs. Oregon Fisheries Agreement was approved, allowing for artificial production techniques for the sake of restoring the salmon population. Based on the data gathered from those PIT and wire tags, it became clear that a limited number of natural origin (wild) salmon come back to spawn. More hatchery fish came back than wild, so they began producing a hatchery-wild crossbreed. Instead of removing the dams, which is likely the most effective way to restore the populations, they’re introducing ways to make the fish more durable when they encounter the dams. By crossing natural origin males with hatchery females, the McCall hatchery hopes to raise 250,000 brood stock to satisfy the U.S. vs. Oregon Agreement. These hybrids will not be marked, or clipped, but will be wire tagged.

One foreseen issue with this method is that fishermen won’t know how to identify this variety if they catch one. Will this variety be considered “more wild” than hatchery-raised, and therefore unlawful to keep? Questions remain as this method reaches full integration (the hatchery is currently in the middle of implementing the integrated brood stock). Joel believes desegregating the hatchery and wild stocks will naturally prepare the hatchery-raised salmon for the wild, albeit after an adjustment period. Since hatchery fish are accustomed to being fed, treated for disease (when necessary), and are somewhat protected from the usual predators, the adjustment period will provide more insight when the time comes.

Some predation does occur on the hatchery grounds. One in a thousand (out of 1.1 million) hatchery salmon return to spawn, so the staff didn’t think much of the ducks that have learned to flock to the hatchery during the winter. Like humans, animals learn quickly how to gain as much as possible, with the least amount of effort; it’s hard for anyone to turn down an easy meal. River otters were considered the strongest predator at the hatchery until the staff found a dead duck on the premises and dissected it out of curiosity, where it found a considerably high number of smolts in the duck’s belly. Now the outdoor rearing ponds are surrounded with netting in the winter to keep the mallards from relying too heavily on their stock. The least invasive predator is thought to be the king fisher, which only visits in the late summer months.  

With so much attention given to how many fish come and go, is the hatchery screening for disease? And how do they ensure disease is not released into the wild? The McCall hatchery has a pathologist on hand during collection, where samples of the females are taken for analysis. At the hatchery, they collect portions of female kidneys to look for harmful bacteria. At the same time, if eggs contain traces of harmful bacteria, the entire tray is culled.

Which made me wonder about organic waste from the salmon. All waste gets moved to a “settling pond” just over the fence from the outdoor rearing tanks. The settling pond is monitored each month for phosphorous levels. Could it be repurposed to grow algae or other waterlife, sort of like a polyculture? (Paul Greenberg discusses the positive aspects of Polyculture in his book). Joel reminded me that the rivers here are already nutrient-rich, and an algae bloom would only be a set back because it reduces oxygen levels in the water as it dies. The only repurposing they could potentially do with the waste in the settling pond is for use as fertilizer, but no one is currently reusing the waste for any purpose.

The tour ended overlooking the settling pond, not yet frozen over. Two ospreys could be seen flying overhead, and Joel pointed to an abandoned roost atop a dead tree jutting out from the water, where a bald eagle is known to return every other year. The snow was falling steadily, and trees across the pond shook and showered snow onto lower branches. For the first time, I noticed a lack of fish smell on the premises. It would not have surprised me to have encountered the fish food and chlorine cocktail aroma that goes hand in hand with pet stores and some aquariums. But surrounded by freshwater that is continuously pumped and oxygenated, you would never know a fish hatchery exists here (this could also be due to the cold weather). As this hatchery does what it can to restore fish to neighboring lakes and streams, it has found a way to avoid interfering with habitats as much as possible, and without invasive sensory overload on neighboring houses just across the pond.

Given what you know about wild habitats and the plight of the salmon, what are your thoughts on the Integrated Brood Stock? Paul Greenberg writes extensively on the implications of messing with fish genomes, but others argue that without some human manipulation, certain species would face extinction.

Have you visited a fish hatchery near you? If no hatchery exists near you, are there commercial fisheries or wildlife protection zones you can visit? I’d love to hear your stories. 

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.