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Note From Todd: this is Part 4 of a 5-Part article – Sea-Run Cutthroat Above Gold Ray Dam – Say What? The article was written by Jay Nicholas, a fisheries biologist with over 30 years experience with salmon, trout, and steelhead in Oregon. Jay was employed for most of his career by the Oregon Department of Fish and Wildlife and now works for the Wild Salmon Center http://wildsalmoncenter.org/ where he is responsible for the North American Salmon Stronghold Partnership. I always wondered if the huge cutthroat we catch above Gold Ray are anadromous or not. This article is Jay’s way of answering my question. Comments about the article should be directed to me at Trophy Waters Fly Shop. http://www.trophywaters.net/index.php
Enjoy.
Part 4
Where are Anadromous Cutthroat in Oregon?
(Officially, that is)
Virtually all Oregon coastal rivers and Columbia River tributaries upstream to Hood River and Willamette Falls support Sea-run cutthroat. From the Necanicum to the Winchuck; from Youngs River to the Hood River, the fish are supposed to be there, in greater or smaller numbers, somewhere in these basins.
The 1995 Biennial Report on the Status of Wild Fish in Oregon catalogued the presence of anadromous cutthroat populations.
http://www.dfw.state.or.us/ODFWhtml/Research&Reports/WildFish/CHAPTER4.html
• Anadromous cutthroat (Sea-runs) are present in tributaries to the Columbia River upstream to the base of Willamette Falls and upstream into Hood River. The Hood is roughly 170 miles from the ocean – a nice example of an exception to the generalization that Sea-run migrations are usually to areas that are less than100 miles from the ocean.
• Sea-run populations are listed for tributaries to the North and South Umpqua Rivers that are over 150 miles from the ocean – another nice long migration distance.
• Sea-run populations are identified in tributaries to the Rogue River basin below Gold Ray Dam – but not above Gold Ray. Gold Ray is a little less than 130 miles from the Ocean; there are about 30 miles of river between Gold Ray and Lost Creek Dam.
Sea-runs above Gold Ray Dam – if not, why not?
Could fish counts at Gold Ray be missing a significant Sea-run migration over the Dam? Probably not. ODFW has used a 24-hour per day video camera at the Gold Ray ladder since 1992. Well-trained people look at these tapes, try to identify marked and unmarked fish, and count coho, Chinook, steelhead, and cutthroat. Could they be missing a few cutthroat? Sure. But I doubt that they are overlooking several hundred large cutthroat each year.
Dan VanDyke, ODFW biologist for the Upper Rogue, provided the following quote that reports what Cole Rivers thought about Sea-runs in the early 1960s.
Cole Rivers (Rogue River Fisheries, Volume 1, 1963) on “migratory coastal cutthroat”—“Although not too numerous anywhere, the run is largest into the lower tributaries including the Illinois drainage. Lower tributaries of the Applegate are highly preferred. Only a few migrate to the upper Rogue above Gold Ray.”
Dan also tells me that “trout” were counted at Gold Ray during 1946-50, but no mention of the size or species was noted for 500-1200 “trout” counted each year. These fish counts probably included a combination of cutthroat, rainbow, and juvenile steelhead. Dan also reminded me that a Master’s study in the 1970s (T. Tomasson 1978) indicated that Sea-runs were most common in the lower river below Agness.
So, OK, I have listened to the experts and now believe that Sea-runs are not common above Gold Ray Dam. Well, maybe they are common (meaning there are always a few fish that sneak into the upper river, but only a very, very low number each year. It will take more data to prove otherwise, eh?
Gold Ray Dam http://www.dfw.state.or.us/fish/fish_counts/gold_ray_dam.asp
Note to self. The process of identifying cutthroat may be a greater challenge at Gold Ray than it is at Winchester Dam on the North Umpqua. Steelhead migrating upstream over Winchester Dam tend to be larger than steelhead passing over Gold Ray on the Rogue. North Umpqua steelhead tend to be big fish of 6-10 pounds or more – fish with a 2- or 3-salt life history. In contrast, Rogue steelhead usually express a half-pounder life history – they spend repeated sessions of around 3 months in the ocean, over-wintering in the river each year. A steelhead less than 20 inches would be unusual at Winchester, but steelhead under 20 inches are relatively common at Gold Ray.
Am I satisfied that Sea-run cutthroat life form never existed in the Rogue above Gold Ray? Nope.
Why not? Although the anadromous life-form of cutthroat above Gold Ray is probably rare today, a few Sea-runs could be making their way over Gold Ray. Maybe, just maybe, a handful of large cutthroat are being overlooked among a lot of similar-size steelhead at Gold Ray. Also, Sea-run cutthroat might historically have been far more common above the Gold Ray. Sadly, cutthroat passing over Winchester Dam on the North Umpqua now average less than a hundred fish a year.
http://www.dfw.state.or.us/fish/fish_counts/winchester/2007/current_winchester_counts.pdf
Fabian Carr counts fish on the Winchester tapes for ODFW. He kindly provided data on the size of cutthroat counted over the dam. I combined data for 2000 through 2006 and produced the following graph to show the sizes of cutthroat counted. When I look at this size distribution, I see a lot of cutthroat in the 12” – 14” category: perfect for Sea-runs returning on their first spawning migration. But let’s not jump the gun here. Fish that are 12 or 13” could be either anadromous or fluvial life histories. Fabian told me that he does see some fish that look really silvery, and these (I think) are probably Sea-runs. The non-silvery cutthroat could be either anadromous or fluvial fish, I just don’t know. Fabian mentioned that Cutthroat are also counted at a station on Calapooya Creek, an Umpqua tributary downstream from the Forks. Some of the cutthroat counted in the Calapooya seem, based on my conversation with Fabian, like they are probably Sea-runs.
So – there are probably at least a few Sea-runs passing Winchester each year, but they aren’t real abundant these years. Sea-runs may have numbered in the 500 - 2000 range in the mid 1940s and 1950s. Notice the qualifier – may have. In spite of local folklore, fishing stories and nearly century-old newspaper accounts, no one really knows how many anadromous cutthroat ran into the North and South Umpqua in the 1800s . Same goes with the upper Rogue. No one has any solid evidence regarding numbers of Sea-run cutthroat in the upper Umpqua or Rogue before people began messing-up salmon migrations with mining, dams and water diversions. An anadromous life history could have been far more common historically, before people began damming the rivers and making large-scale habitat changes. Most likely, the life history diversity that we see in our native salmonids here in Oregon, today, is a meager leftover compared to the diversity that these fish expressed 200 years ago.
What about the monster (16” – 22”) cutthroat that are being caught above Gold Ray Dam in recent years: don’t they have to be Sea-runs? Nope. Remember, it is impossible to distinguish fluvial, anadromous, or adfluvial cutthroat based on size alone or even on scale pattern analysis.
Sea-run cutthroat are very clearly identifiable by appearance for only a very short time after they return to freshwater from the ocean or estuary. This color-phase of Sea-run cutthroat is where the term Blueback originated. These fresh-from-the-ocean fish have steel-blue backs, the most beautiful silvery sides, white bellies with no spots, and only very faint orange slash-marks under their jaw. After only a few weeks of freshwater residence, however, they revert to their stream-phase coloration – coppery or brassy hues with lots of spots and blotches of yellow. When an honest-to-gosh Sea-run cutthroat has been in the river for a month or so, I don’t believe that anyone could distinguish it from a fluvial or adfluvial fish. Depending on how fast a Sea-run migrated from the estuary to the counting station at Winchester or Gold Ray, the fish could look just like a fluvial fish – no one could tell from its size or appearance.
Once Again: If not, Why not?
I believe that Sea-run Cutthroat were historically abundant in the South Umpqua, and were a regular part of anadromous fish runs in the North Umpqua also. If so, why wouldn’t Sea-runs have been a regular part of the fish runs into the Rogue above Gold Ray as well? Maybe they were. Maybe Sea-runs, today, are just a tiny fraction of the runs that once existed in the Rogue basin. Gold Ray’s distance from the ocean doesn’t seem like a sufficient reason to dismiss the historical existence of anadromous cutthroat in the upper Rogue. Maybe, today, ecological conditions in the Rogue above Gold Ray are such that they favor the fluvial over the anadromous life histories. It would be nice to know what the runs of cutthroat in the Rogue were like 200 years ago – where were the Salmon–trout distributed in the Rogue, compared to where they are today.
Next up – Part 5: Closing Thoughts on Sea-runs n the Upper Rogue
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