Biters & Fighters (Building a Better Hatchery Steelhead) by Don Roberts
Frank Moore, who lives and breathes the North Umpqua, claims he can distinguish between a wild steelhead and a hatchery fish by feel alone. There have been instances when he put cash behind his castigation—betting the local ODFW biologist that upon hooking a steelhead on his favorite 8-wt. he could accurately pronounce the fish either wild or hatchery, long before ever laying eyes on it.
“I’ll bet you a thousand dollars,” Moore taunted the ODFW guy, “I can tell whether or not I’ve hooked a hatchery fish before I land it.” He wasn’t kidding. About the money or the fish.
While perhaps taking a bolder stance than most, Moore is not the only one to register low esteem for certain hatchery steelhead; so do some guides and veteran anglers on particular rivers. On the other hand, plenty of people in the sporting realm, not to mention agencies tasked with propagating and managing said stocks, scoff at such cantankerous allegations (though none have taken Moore’s wager). Bare-knuckled assertions aside, what does science have to say on this matter?
Eggs and Dogs
As Paul Greenberg, author of the book Four Fish, pointed out: for one reason and one reason alone, salmon (and trout) are far easier to grow in monocultures (hatcheries) than almost any other fish species. That reason can be summed up in a single word: eggs.
Because salmon and trout lay relatively large, oily, highly visible eggs, usually orange in hue, they are comparatively easy to spawn and raise in captivity. It doesn’t take an advanced degree in molecular biology or embryology to start churning out salmon with much the same fervor as backyard gardeners cultivating chickens. In fact, the first record of human-manipulated reproduction of salmon (Atlantic salmon) occurred in France right around the year 1400 AD.
The success of today’s hatcheries is perhaps most clearly manifested in the mass production of rainbow trout, which, as a result, end up being carpet-bombed into lakes and streams across the entire continent. While other species evolved for more narrowly specific niches, the rainbow’s tolerance for warmer temperatures and marginally pure water, provided it the colonist’s advantage. If the prime directive is to proliferate, the rainbow trout ranks up there with the planet’s hundreds of millions of dogs.
Rainbow trout have so fluidly exploited the utility belt of its genes and the ministrations of hatcheries that it has earned the mantle of what Gary Thorgaard, a professor at Washington State University’s School of Biological Sciences, calls “a world fish.” And like the domestic dog, says Thorgaard, the rainbow now cultivated on six continents is a different beast than its wild relatives.
Thorgaard observes: “From a genetic standpoint, with fish that have been propagated for a very long time, many generations in a hatchery, you’re essentially selecting for a very different animal. The wolf/dog analogy is a good one. Essentially, we’re creating a race of dogs that thrive around people but if you release them into nature, they’re not going to survive as well as a wolf would.”
So, it’s no surprise that freshly-released, catchable-size hatchery trout often strongly resemble, at least in temperament and life skills, litters of puppies. What about salmon and steelhead?
The Toughest Smolts on the Block
It never fails, notes Paul Greenberg, that “when wild stocks become over-exploited (intensely harvested), we turn to domestication.” And hatchery fish are nothing if not domesticated. It starts in the cradle, almost from day one. In nature one of the greatest selection pressures on wild salmon is the weeding out that happens during the highly vulnerable transition from egg to juvenile. By contrast, eggs babied and coddled in a hatchery, where every aspect of their environment is regulated and controlled, survive to produce an unnaturally high percentage of juveniles, including those that should not survive—genetically inferior small fry.
Recently scientists have learned that it may not even take a generation to change DNA. Genetic experiments involving circadian rhythms (daily light and dark cycles), and biochemical oxytocin, have shown that the DNA an animal is born with is not necessarily a frozen map.
Experiences, especially anthropogenic (manmade) experiences—stimuli—can alter genes in an unbelievably short time frame. With that in mind, consider the typical hatchery environment: artificial lighting, confined space, crowding, clockwork feeding regimes, and rigid security (total lack of danger). Though undeniably bland, life in a hatchery is an amalgam of unnatural experiences. Never mind the possible ramification of altered genes, given behavioral conditioning alone, is it any wonder that hatchery juveniles often turn out to be so unwary and recklessly unafraid—so vulnerable to predation?
Perhaps the surest, most resolute means to getting tough is to be raised in a tough neighborhood. And there are no tougher neighborhoods than the bloody-of-tooth-and-claw burroughs of nature itself.
Greenberg’s examination of this topic includes a passage about a fish reclamation project in Merry Old England. “Around the world, while salmon geneticists try to make salmon more and more efficient and fit for a tank, there is starting to emerge a kind of reverse engineering in which wild-salmon advocates are applying more science-based methods to make tank-reared salmon fitter for return to the wild. In rivers where salmon had gone nearly extinct, like the river Tyne on the northeast coast of England, salmon rehabilitators are starting to find that the genetic complexity we have lost and fetishized over the last half century may not necessarily be the only key for staging a wild salmon resurrection.
“…Not a single salmon returned to the Tyne in 1959. It might have stayed in this condition had it not been for a biologist and sport-fisherman named Peter Gray, who decided to go against the popular conclusions in the arguments about salmon and genetics. ‘If we go back to just after the last ice age,’ Gray wrote, ‘all our salmon rivers had to recolonize. The genetic integrity had to start all over again.’ Somehow, from a small genetic redoubt, they were able to reclaim their kingdom. There is a metagenetic component that must be respected…West-coast Scottish salmon “turn right” to go north to Greenland, whereas, east-coast salmon “turn left.” Putting a west-coaster in an east-coast river could send fish on a deadly holiday to France.
“But if you have these metacomponents correct, you can start to goose salmon back to viability. Gray believes that we must get away from the mammoth hatcheries…Genetics are important…but he has found that properly preparing juveniles for reintroduction and timing the stocking of rivers is even more so; it means the difference between success and failure. Hatchery-born salmon, it turns out, have to be taught what it’s like to be wild again in order to make it. Gray introduces strong river-like currents in their larval tanks. He feeds them (live) insects and other food they will encounter in the wild when reintroduced to the river. And he releases them at a time when he knows (the same thing nature once knew) other predators in the river will be largely absent or not feeding. All this has meant a complete reversal in the fate of the Tyne. Within thirty years of starting his efforts, he has brought the Tyne back to the point where more than twenty thousand adult salmon return to spawn every year.”
Equal Opportunity Impregnator
Many biologists argue that while nurture—how offspring are raised—has a pronounced effect upon fitness and possibly the DNA of salmon, nature—the genetic traits inherited from previous generations—has an even more profound impact upon their vitality. In other words, pedigree is paramount. Unfortunately, the husbandry methods employed by many of today’s hatcheries remain suspect.
Don Campton, Science Advisor for Fishery Resources at the U.S. Fish & Wildlife Service, doesn’t hedge when addressing the issue. He flatly states, “Hatchery spawning practices can result in genetic changes in hatchery populations over time (i.e. over multiple generations).” Campton is particularly critical of “pooling”—the indiscriminate mixing of eggs and milt (sperm) from several male and female salmon simultaneously. “That ill-advised method is one mechanism that can result in very significant genetic changes between generations. In our hatchery reform efforts, I try to emphasize that our spawning goals are to maintain viable, self-sustaining, and genetically diverse populations. That is a different goal than simply “producing fish”.”
In 2004, Campton wrote a report excoriating outdated spawning protocols, pointing out that the problem with the mixed-milt approach is that it leads to significant sperm competition and highly unequal genetic contributions from male spawners.
Think of it this way—male salmon unwittingly vie for the prize of siring offspring via the one-celled messengers of themselves: their sperm. Or, for the MLS fans out there, think of a hatchery spawning tray as a Major League Soccer field: not eleven, but 11 million players jostling to get into the egg…and no goalkeeper.
“Sperm contribution in vitro (Latin for in glass or, more specifically, test tube) can result in undesirable artificial selection of life history traits (e.g. age or size at maturity) that are correlated phenotypically with sperm potency and fertilization success.
A large number of salmon hatcheries in the Pacific Northwest, particularly those within some state agencies, continue to use mixed-milt fertilization despite documented genetic effects and potential risks…As a general rule, salmon hatcheries should discontinue mixed-milt fertilization and institutionalize alternative spawning protocols that preclude or minimize sperm competition in vitro.”
Three such alternative protocols stand out:
- pairwise spawning,
- nested spawning
- factorial or matrix spawning.
“The underlying premise of these protocols, Campton noted, “is that every adult selected for use as broodstock should have an equal opportunity—and an equal probability—of producing progeny.”
Given that nearly 30 years have elapsed since a scientific study established (confirmed by subsequent studies over the past two decades) the deleterious effects of sperm competition—a direct result of pooling—in hatchery salmon, it’s somewhat mind-boggling that a large number of hatcheries continue to rely on mixed-milt fertilization.
Campton advocates mandating “increased genetic oversight of hatchery operations comparable to the level of fish health oversight (i.e. the pathogen monitoring and disease prevention) currently practiced in salmon hatcheries throughout the Pacific Northwest.”
In the interest of stronger, healthier stocks, selective spawning protocols should be policy, if not enforced procedure, during all hatchery production. Is this a call for the formation of fish spawning police? Well, sort of…
In the meantime, it’s not unreasonable to wonder why so many of the larger hatcheries, veritable fish factories, shun the husbandry strategies necessary for producing robust, canny and feisty (biters) stock.
Instead, these mega-hatcheries seem content to embrace those selfsame, fusty and outdated spawning practices that have proven culpable for manufacturing assembly-line generations of fish—an unholy mix of the good, the bad and the ugly. Or, in the worst case scenario, Oncorhynchus oscarmayerus, weenies with fins.
Update: Attack Mode on the Alsea
After years of complaints about passive hatchery-bred steelhead—“the damned things won’t bite”—on the Alsea, ODFW decided to do something about it. The perception of non-aggressive steelhead is not just a fish story: the first year—of an ongoing three-year creel survey on the Alsea—found that steelhead of wild-parentage were caught by anglers three times more often than those from longstanding hatchery stock. Tranquil hatchery fish are not a fluke limited to the Alsea. For instance, during 2013 on the Deschutes River (the most recent survey data available)—where hatchery fish outnumber wild fish by three to one—creel counts indicated that nearly six wild steelhead were caught for every hatchery steelhead. Something about that ratio just doesn’t add up.
Way more hatchery fish, way fewer biters—what’s an agency to do?
Prodded by distressed locals, the Oregon Hatchery Research Center, OHRC, decided to take a hard look around for possible solutions and ended up focusing both a critical eye and an open mind on, what else?, black bass.
In 2009, the scholarly international journal Transactions of the American Fisheries Society culminated a 30-year study on the effects of sport harvest of black bass in an Illinois Lake. The study showed that removing the biters, which are even more aggressive while defending their nests during the spawning phase, over succeeding generations produced increasingly domestic offspring. In short, here was proof that the tendency to bite can be inherited (but not if there are no biters left to breed). Or the converse, the tendency not to bite can be inherited. As David Philipp, the study’s lead author, noted: “As a result (of selective harvest), the population becomes less vulnerable to angling because it is less and less aggressive.”
Observing that it made little sense to spend millions churning out uncatchable fish (sport bag being the intention of hatcheries), OHRC director Ryan Couture, acknowledged that it was time to instigate an “experiment on whether hatchery-produced steelhead can be bred to be better biters.”
Although, as already noted in this article, numerous variables (and possible changes) for raising and stocking hatchery fish need be examined, the obvious first step is to draft the existing biters—wild fish caught and kept alive—into the hatchery breeding program. Continue the biters-as-breeders protocol for long enough and, who knows, maybe one day the majority of returning adults in the Alsea will come to far more closely resemble lions than lambs.
- written by Don Roberts