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A question to the biologists and armchair biologist, amateur geneticists.

I get that we have natural Cuttbow in the populations and gene pools. Coastal Cutthroat x Coastal Rainbow-Steelhead, we have Redband Rainbow x Westslope Cutthroat.

Are there Coastal Cutthroat X Westlope Cutts? Redband Rainbow X Coastal Cutthroat?

I guess the Redband Rainbow Steelhead, versus Coastal Rainbow/Steelhead is something I have been trying to wrap my head around as well. The Columbia harbors both until they reach the stream of choice and segregate appropriately ? I get it when natural barriers isolotate populations and they evolve into different creatures, but are these fish the same/cousins/different?

I will hold off the urge to think of natural Bull X _____native fish, here.

Been reading of the stray Atlantic Salmon escapees ending up in NW rivers..and of the Brown Trout in the Cowichan in BC.

Wonder what the heck is possible and the heck is there right now?

I guess our rivers, each stock-full of their pure brand of native Steelhead would suffice !
-have read the Cowichan River on Vancouver Island is at full natural carrying capacity. Can you imagine a WA river saying this??
 

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Just an Old Man
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A question to the biologists and armchair biologist, amateur geneticists.

I get that we have natural Cuttbow in the populations and gene pools. Coastal Cutthroat x Coastal Rainbow-Steelhead, we have Redband Rainbow x Westslope Cutthroat.

Are there Coastal Cutthroat X Westlope Cutts? Redband Rainbow X Coastal Cutthroat?

I guess the Redband Rainbow Steelhead, versus Coastal Rainbow/Steelhead is something I have been trying to wrap my head around as well. The Columbia harbors both until they reach the stream of choice and segregate appropriately ? I get it when natural barriers isolotate populations and they evolve into different creatures, but are these fish the same/cousins/different?

I will hold off the urge to think of natural Bull X _____native fish, here.

Been reading of the stray Atlantic Salmon escapees ending up in NW rivers..and of the Brown Trout in the Cowichan in BC.

I wonder what the heck is possible and the heck is there right now?
I wouldn't think to hard on this subject as your head will probably explode.:rolleyes::rolleyes::rolleyes::rolleyes:
 

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I believe that the Yakima is the western edge of Westslope Cutthroat species historical range.
That explains a lot, when ever I go fishing on the west coast, I never seem to be able to catch any cutthroat, those guys that claim success on the salt water beaches and our coastal rivers are just fibbing..........;)
 

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Now hanging at the other, better new place
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Jim, not saying it wouldn't happen but the likelihood that Coastal Cutthroat spawning with Westslope seems very far-fetched.
I don't know if I'd say it's "very far-fetched" in places where they occur sympatrically due to stocking. I'm thinking specifically of the Upper South Fork Snoqualmie, where hatchery lineage Westslope Cuttthroat occur along with a mix of native and hatchery lineage Coastal Cutthroat. I've caught some odd-looking trout up there.
Fish Ray-finned fish Tail Terrestrial plant Terrestrial animal


"Samples from the Denny Creek segment of the Up SF (n = 4) were either pure or hybridized hatchery westslope cutthroat. No samples obtained in the Up SF and Mid SF matched pure native Snoqualmie O. clarki. Conversely, most matched pure native Cedar O. clarki (29%), Cedar O. mykiss (29%), and hybridized Cedar O. clarki/O. mykiss

(20%). The Asahel Curtis segment of the Up SF and Tin- kham segment of the Mid SF contained the highest pro- portions of Cedar O. clarki (62%) and hybridized Cedar O. clarki/O. mykiss (19%). No coastal cutthroat trout of native lineage were sampled in the Weeks Falls and Grouse Ridge segments, but hybrid Cedar O. clarki/O. mykiss (21%) and Cedar O. mykiss (50%) represented the majority of genetic samples in those segments. A few mixed hatchery/native rainbow and coastal cutthroat trout were also sampled in these segments (25%). In the Low SF downstream of Twin Falls, pure hatchery O. mykiss were sampled (8%) as were native Cedar O. mykiss (16%) and hybrid Snoqualmie and Cedar O. clarki/O. mykiss (18%). Mixed native Sno- qualmie O. clarki/Cedar O. clarki (5%) were sampled in the Low SF as were hatchery/native mixed coastal cutthroat (5%) and hatchery/native mixed hybrids (13%)." (Snoqualmie River Game Fish Enhancement Plan: Final Report of Research, WDFW November 2011)
 

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Matt -

Good stuff! It is interesting how things have changed over time. I grew up fishing the lower forks of the Snoqualmie and they were my "play ground" during the 1960s. During the period I caught many thousands of trout and don't recall every seeing a rainbow (other than planted catchables) looking trout on the SF downstream of Twin falls or on the middle fork below the Pratt. There lots of rainbows on the North Fork and the Middle fork in the Taylor River area though in the very upper limit of Middle Fork distribution (Pedro camp) it was all cutthroat (introduced by miners?). Now some 50 years later sounds like rainbow or hybrids are much more common. I agree fish dropping downstream for alpine lakes are a likely source for various exotic trouts.

While chasing sea-runs on the lower ends of the north sound "S" rivers I have caught a very small handful cutthroat that look to have some westslope blood; coastal/westslope hybrids? Know that resident westslope cutthroat are found in the upper reaches of all three systems.

Curt
 

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After Mt. St. Helens blew, some of the coastal cutts in Coldwater Creek survived the blast under the ice/snow of the creek. A few years later, WDFW stocked rainbows into the Coldwater Lake, which was created by the eruption. However, the source hatchery in eastern Washington was also raising westslope cutts. Somehow, some of those westslope cutts made it into the hatchery trucks with the intended rainbows. Now, 25+ years later, you can still catch the very-occasional cutt that looks pretty pure coastal and other cutts that look pretty pure westslope. I guess only a genetic analysis would be able to confirm their "purity". One wonders if the westslopes and coastal cutts have either spatial and/or temporal differences in spawning that would maintain genetic isolation.
Steve
 

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The rainbow and coastal cutthroat are still relatively close genetically, having only begun to evolve from a common ancestor a mere 3 million years ago. The dictionary definition of "species" usually includes something about being sufficiently different genetically to be unable to produce viable or fertile offspring. This is not the case with with coastal cutthroat and rainbow trout. Having evolved sympatrically these two species have been able to maintain their identities largely by reproductive isolation, rainbow/steelhead preferring larger streams for spawning while coastal cuthroat show a marked preference for he smallest imaginable streams. This tactic does not work in the intermountain west where rainbows are non-native, having been introduced by man, and has resulted in "hybrid swarms" of so-called "cuttbows". Hybridization does occur between coastal cutthroat and rainbows but the offspring usually seem to exhibit the physical characteristics of only one of the parents andsuch hybridization does not seem to have resulted in the large numbers of "cuttbows that occur in areas where most the rainbow is not a native.

The native range of the westslope cutthroat is considerably upstream of the mouth of the Yakima and the Yakima westslopes are thought to be the result of early stocking from watersheds further north (Chelan, Entiat, Methow).
 

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The rainbow and coastal cutthroat are still relatively close genetically, having only begun to evolve from a common ancestor a mere 3 million years ago. The dictionary definition of "species" usually includes something about being sufficiently different genetically to be unable to produce viable or fertile offspring.
Under some speciation models, two valid species can still produce fertile offspring, but the offspring may be at a selective disadvantage and have lower overall fitness (e.g., lower but not zero reproductive success, lower but not zero survival, poorer but not zero growth). This acts as a barrier to the spread (swamping) of genes from one species to the next, a block to introgression.
Steve
 

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This is the answer that the YRHTU Chapter will be pursuing over the next eight years of study; are there genetically pure Westslope Cutthroat in the Yakima, which tributaries are they utilizing for spawning and refuge in a changing climate, and what if any modifications would best benefit their populations. During snorkeling outings in the headwaters, we've seen some interesting things.

The rainbow and coastal cutthroat are still relatively close genetically, having only begun to evolve from a common ancestor a mere 3 million years ago. The dictionary definition of "species" usually includes something about being sufficiently different genetically to be unable to produce viable or fertile offspring. This is not the case with with coastal cutthroat and rainbow trout. Having evolved sympatrically these two species have been able to maintain their identities largely by reproductive isolation, rainbow/steelhead preferring larger streams for spawning while coastal cuthroat show a marked preference for he smallest imaginable streams. This tactic does not work in the intermountain west where rainbows are non-native, having been introduced by man, and has resulted in "hybrid swarms" of so-called "cuttbows". Hybridization does occur between coastal cutthroat and rainbows but the offspring usually seem to exhibit the physical characteristics of only one of the parents andsuch hybridization does not seem to have resulted in the large numbers of "cuttbows that occur in areas where most the rainbow is not a native.

The native range of the westslope cutthroat is considerably upstream of the mouth of the Yakima and the Yakima westslopes are thought to be the result of early stocking from watersheds further north (Chelan, Entiat, Methow).
 

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I believe that the Yakima is the western edge of Westslope Cutthroat species historical range.
Most of the west slopes, native or stocked, I've caught were caught on the western slopes of the Cascades. The dividing point of that range from the coast may be a more accurate example
 
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