This article sent my brain reeling. I have so many questions, all of which I suspect are wildly stupid but I have zero experience with fish. (Please be kind.)
Are these then considered introduced? Captive because they are tagged? (Very confused)
Could they conceivably survive in this place?
I know salmon travel great distances – could they travel to better waters if need be?
Those are very good questions!
I took a break to read the article.
“The 77,000 fish that made it into Lookingglass Creek will likely return there and produce approximately 350-700 additional adults,” the statement said.”
So, yes, they can survive, are expected to migrate to the ocean and make it back to this river. Could have been worse.
These are fish that are being restocked and that restocking will continue, but into the planned river.
Oh that captive question! I would call them introduced in this case, as they are in an unintended river.
They were raised to this point by human care, and from here on their own. That’s all I’ll say on that.
In that watershed they would be introduced and wild I think. No idea about the ecological impact, but I am assuming that 70,000 of any reasonably sized mid-tier predator will cause an ecosystem impact while they are around. However, the specific situation in the release river will play a major part in determining the outcome.
It looks like chinook have already been reintroduced to this creek and are successfully breeding: “For decades, the Nez Perce Tribe and the Confederated Tribes of the Umatilla Indian Reservation have been working to return salmon to Lookingglass Creek and other habitats in the area, looking to restore historic cycles of animal life and human tradition.” via NPR
If this creek is already in the species’ current range, I would not call it catastrophically bad. There has always been some degree of mingling in anadromous fishes – if you figure that new rivers have come into existence since the species evolved, those rivers were initially colonized by fishes who lost their way, blundered into the “wrong” river, and found it suitable. Contrary to some current schools of thought in conservation, species have always introduced themselves to new places and formed new interactions.
As we say here, no questions are stupid. I’ll try to privide insight for each of yours. By way of intorduction, I spent 25 years working for the U.S. Government on Pacific salmon conservation issues, including the Columbia and Snake Rivers. I retired a few years ago, and don’t know details of these particular fish, but I know the general issues involved.
Very confused, just like most people who try to figure out modern salmon management. The terminology surrounding “wild” and “hatchery” salmon and the various levels of genetic relatedness among stocks has become very specialized, because absolute terms like “native”, “introduced”, “wild” and “captive” don’r really mean much anymore with the long history of human management. These particular hatchery-reared fish are part of a supplementation program, adding fish to a natural population to help maintain its numbers. The original Chinook salmon in the Imnaha River and Lookinglass Creek were part of the same major genetic lineage, so are pretty closely related. Thus, while the spilled fish were “introduced” into the wrong creek, they are quite similar to the native fish there. They did start life as “captive” in the hatchery, but will spend the majority of their lives in natural systems in the rivers and ocean.
Yes, they should do quite well in the creek. Salmon are weedy (do we still say “r-selected”) species with high fecundity and an ability to survive in a wide range of conditions. It’s actually pretty amazing that we’ve been able to drive some stocks close to extinction - we must have tried very hard.
Those that reach adulthood will have travelled a lot - a couple hundred kilometers down to the ocean, a few thousand km in the ocean, then back upstream to spawn (ca. 2 to 5 years from now). Salmon have a strong tendency to return to their natal stream, but it varies by their rearing history and how distinctive the water in their natal stream is. My recollection is that these stocks have about a 90% homing fidelity, but that could be off a bit. Regardless, most of them would be expected to return to Lookingglass.
Most certainly! They will travel with other spring-run Chinook throughout their lives, and those that survive to spawn will interbreed with the local fish when they return.
No, it is not catastrophic. From the perspective of the Imnaha rebuilding program, this is the loss of one truckload in one year - it’s an undesireable loss, but is unlikely to make or break the program. From the Lookingglass perspective, there may be some issues of introducing non-local genetics, but these should be closely-related fish.
The actual catastrophe has happened over the last hundred years or so of industrializtion of the Pacific Northwest which transformed the river system from fast-flowing cold water into a series of slow, warm reservoirs, overharvest, poor hatchery practices that brought in diseases and mal-adapted genetics, irrigation diversions, and habitat destruction. Some of that is slowly being improved, but not nearly enough to compensate for the added risks due to climate change.
For decades, the Nez Perce Tribe and the Confederated Tribes of the Umatilla Indian Reservation have been working to return salmon to Lookingglass Creek
And in all those years they never once thought about crashing a truck into it with 77000 salmon inside, when that is obviously such an effective solution? :P
(For legal reasons this is a joke and I don’t advocate for crashing trucks into anything)
Jokes aside, is there really such a huge difference between “naturally” bringing back species and (re-)introducing into their original habitat individuals of those species that have been bred by humans?
I also once heard people discourage someone to reintroduce threatened butterflies they have bred into their original habitat.
I can see why 77000 individuals at once would be problematic, but if it were done gradually?
I think reintroduction can be valuable but with two important caveats.
The conditions that first caused the species to be lost from an area need to be changed/ameliorated before reintroduction will have any positive effect. If they aren’t, reintroducing individuals is probably just a waste of resources as they’ll likely just fail to establish anyways. For instance, with salmon, if the original populations went extinct due to overfishing or the presence of dams, and overfishing and the dams are still present, reintroducing individual fish isn’t going to help - they’ll just be caught/eaten or not be able to migrate properly.
Not all individuals of a species are the same when it comes to genetics or traits. Reintroducing individuals with a different genetic makeup can actually harm local populations via maladaptation. For instance, if I introduced a bunch of seedlings bred from the southern portion of a plant’s range into the northern portion, those seedlings would likely be from individuals adapted to the local conditions in the south (warmer, maybe different rainfall, different phenology). If they interbreed with northern plants, the offspring could actually have reduced survival/reproduction as they wouldn’t be well adapted to colder/shorter growing seasons, causing harm beyond just the potential loss of the seedlings. The same could be in play for other organisms like butterflies or salmon. In salmon, many watersheds have distinct populations with distinct genetic makeups that conservationists often try to maintain (whether we are sure that there is local adaptive value or not). Introducing salmon sourced from one watershed to another can wipe out that variation/homogenize the species. This can make them less resilient to future changes. In general, we want to manage for maintenance of genetic diversity.
So, in sum, reintroductions should only be done when carefully planned, when the origins of the individuals introduced are well established and appropriate, and when the conditions that harmed the preexisting population have been corrected at least to some extent. On a more practical note, introducing/reintroducing without permits may also be illegal in lots of places.
Thank you so much for all this information. I have another question. You said:
Is that because they were spilled there or because the original fishery was there, not far from where they were spilled?
I guess I am asking what age is the natal stream established in their honing? Sorry, I am finding this very confusing, because on the map provided, the creek where they were spilled and the destination seem to be connected waterways, so they were just going to be put there… why? If 90% would come back to where they were born, what would be the purpose of moving them? (Why not breed them where you want them?)
That’s a tricky question to answer, and I’m not an expert on the physiology of homing. As a general hatchery practice, salmon are released at a stage before they fully impress on their location, specifically so they will return near the release location rather than the location of the hatchery. As to your question of why they are reared at a location away from where they are to be released, it comes down to economics - hatcheries are expensive (and hard to get permits to be built now), so the larger hatcheries will raise fish of different stocks for different destinations. Trucking fish is a lot cheaper than building and staffing a local hatchery on every stream.
Agree fully. In this case of hatchery-reared salmon, there is a long history of bad hatchery practices leading to genetic mixing of mal-adapted stocks – in fact, we have declared some salmon populations functionally extinct because there had been so many out-of-area fish outplants that native local genetics were no longer present. Happily, those practices hves largely been addressed, and almost all salmon hatcheries in the U.S. are now required to have genetic management plans in place for each stock they raise.
They would be introduced if this taxon was not present in the river prior to human intervention, and native if these were just more individuals in the same species/subspecies that already lived there.
They would be wild because they are in nature in a river and not confined by humans
I think in iNaturalist these would be considered “captive/cultivated” because they were bred and raised by humans in a hatchery before they “escaped” when the truck overturned, analagous to a pet dog running loose in the woods. But once released they can’t be easily differentiated from wild fish unless they were marked in the hatchery (which these probably were by having their adipose fin clipped off, and most likely with internal tags as well).
A pet running loose is an animal that returns to it’s owner regularly for food and shelter, these fish have been completely freed of any human care or confinement as soon as they left the truck, so they would be more like a stray dog, which is considered wild
“Checking captive / cultivated means that the observation is of an organism that exists in the time and place it was observed because humans intended it to be then and there. Likewise, wild / naturalized organisms exist in particular times and places because they intended to do so (or because of intention of another wild organism).”
I would interpret this to mean that, at least for some time after release, hatchery fish are still “captive/cultivated” because they exist in that place because of intentional human actions, but at some later time, after they have volitionally migrated (perhaps to new habitats), they would transition to “wild.” This is splitting hairs, and still results in a judgment call for anyone observing hatchery fish in nature.
The same issue is a problem for plants: are native plants that were human-cultivated specifically to be planted in natural restoration areas wild or cultivated? I’d argue they are still cultivated so long as humans are tending them (e.g. watering, suppressing weeds, or fencing), but then would be considered wild after they’ve survived on their own for a few years. Otherwise, as someone pointed out in another thread a while ago, there would be very few “wild” forest trees in North America because most have been replanted after logging.
How would salmon know where their hatching location is, or rather how to get to it, if they have been moved in a truck or otherwise transported by humans?
Or does releasing more mature individuals just mean they won’t return to anywhere/they will go some random place?
