Fluvial, Adfluvial, and Resident In Layman's Terms?

Old406Kid

Old406Kid

Legend
I spent some time trying to learn more about these distinct habits as they relate to Westslope Cutthroat but so far what I've found was more 'Latinese" than what I was looking for.
Can anyone point me to a good article that goes a little beyond the definition of each?
 
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Not sure if this will help or if this is what you are looking for.
Fluvial - spend time in their natal streams before migrating to larger river systems.
Adfluvial - spend time in their natal streams before migrating to lakes.
Resident - live their entire lives in the smaller upper reaches of streams and tend to be much smaller in size.

Obviously not all fish follow the rules, so how long fluvial and adfluvial spend in their natal streams before migrating will vary.

If this is a repeat of what you already found in your research, please disregard this post.
SF
 
What @Stonedfish and @Mossback said. Despite the Latin names, it really is a simple description of the relationship between adult life strategies/behavior and spawning strategy.
Fluvial - Adults live in larger rivers and spawn in smaller tributaries (think Yellowstone Cutthroat trout in Paradise Valley - they live in the Yellowstone but spawn in tribs like Mill Creek, Pine Creek, Big Creek, Gardner River)
Adfluvial (often termed lacustrine) - Adults live in lakes and migrate to spawn in tributaries (think YCT in Yellowstone Lake - they live in the lake but spawn in tribs like Pelican Creek.
Resident - Isolated in stream headwaters for entire lifecycle - unable to migrate to lakes or larger rivers

And of course there is: Anadromous - Where adults live in the sea and migrate to freshwater to spawn. Westslopes do not exhibit this life strategy but the Coastal Cutthroat trout does.
 
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An interesting aspect of the Willamette River in Oregon is that it holds both Anadromous and Fluvial fish. You of course have the salmon and steelhead but also the native cutthroat trout. The salmon and steelhead are Anadromous and the cutts are Fluvial. ... they use the Willamette as a highway and can be there today and gone tomorrow. They also use the tribs to spawn so if you know which tributary are most used and when, you can catch some very large cutthroat one day and nothing the next... I speak from experience.
 
I have also been somewhat confluvzed about these terms. Thanks!
 
I always mix them up also. I know practically the wild redbands and bulls in this area present in three or all four behavioral forms.
 
What we are talking about is the various life histories (pr behaviors) a given fish might express within the river or ecosystem.

A simple way to look at the above is for the young fry hatchery in a tributary have a variety of life choices. If they opt to remain in the spawning tributary they are sometimes referred to as headwater residents. Those fry that move downstream to find rearing/feeding habitats are often referred to adfluvial fish or residents, while those that migrate downstream (or upstream) to lakes for those rearing/feeding opportunities are referred to adfluvial. Those that migrate downstream to the salt are expressing the anadromous life history. To confuse the situation a given population may have siblings exhibiting more than one of those life histories and it is not uncommon to see individuals with different life histories interacting on the spawning grounds.

Just to further confuse things it is not uncommon for a fish to change life histories during their life times (mid-age crisis?). For example out of approximate 150 Skagit bull trout 8% had changed their life histories; fluvial fish becoming anadromous, anadromous becoming fluvial or even headwater residents switching one of the migratory fisheries. It is almost life the fish resist being place in those nice neat boxes that are so attractive to the human mind.

Suspect the above does not help.

curt
 
And then potadramous which is kinda like great lakes fish, and catadromous (iirc) where a fish lives in fresh water but spawns in salt (like american eels and i think blue crabs)
 
Old406Kid said:
I spent some time trying to learn more about these distinct habits as they relate to Westslope Cutthroat but so far what I've found was more 'Latinese" than what I was looking for.
Can anyone point me to a good article that goes a little beyond the definition of each?
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Contact a WDFW biologist for your area and ask you questions, he or she should be able to fill you in on anything
 
singlehandjay said:
Contact a WDFW biologist for your area and ask you questions, he or she should be able to fill you in on anything
Click to expand...
Thanks, that's definitely an option but I hate to bug them when they more than likely have better things to be doing.
What started this is a friend of mine and I were discussing it and I think he has it bass ackwards.
He swore by what he was saying and said it came from a biologist that spoke at a club meeting.
 
Old406Kid said:
Thanks, that's definitely an option but I hate to bug them when they more than likely have better things to be doing.
What started this is a friend of mine and I were discussing it and I think he has it bass ackwards.
He swore by what he was saying and said it came from a biologist that spoke at a club meeting.
Click to expand...
You might be surprised. Some people really love it when you take interest in something that not a lot of people really dig into. If you get an email address that you can ask your question, worse they can do is not respond
 
Smalma said:
What we are talking about is the various life histories (pr behaviors) a given fish might express within the river or ecosystem.

A simple way to look at the above is for the young fry hatchery in a tributary have a variety of life choices. If they opt to remain in the spawning tributary they are sometimes referred to as headwater residents. Those fry that move downstream to find rearing/feeding habitats are often referred to adfluvial fish or residents, while those that migrate downstream (or upstream) to lakes for those rearing/feeding opportunities are referred to adfluvial. Those that migrate downstream to the salt are expressing the anadromous life history. To confuse the situation a given population may have siblings exhibiting more than one of those life histories and it is not uncommon to see individuals with different life histories interacting on the spawning grounds.

Just to further confuse things it is not uncommon for a fish to change life histories during their life times (mid-age crisis?). For example out of approximate 150 Skagit bull trout 8% had changed their life histories; fluvial fish becoming anadromous, anadromous becoming fluvial or even headwater residents switching one of the migratory fisheries. It is almost life the fish resist being place in those nice neat boxes that are so attractive to the human mind.

Suspect the above does not help.

curt
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Question for you Curt, is there a differentiating term for anadramous fish that go to the open ocean vs ones that residualize to the estuary/coast? For instance a blackmouth in the sound vs an alaska bound chinook, or a rogue half pounder vs a steelhead?
 
Pink Nighty-
Just to make things more confusing anglers often refer to those anadromous Chinook and coho that stay locally in Puget Sound rather than migrating to the open ocean as "residents" or sometimes in the case of those resident Chinook they are also called "blackmouth".

The case of the "half pounders' of southern Oregon/North California is pretty interesting. Rather than migrating towards the Gulf of Alaska as northern stocks of steelhead they take advantage of the nearby offshore cool upwelling called the Humboldt upwelling for their ocean feeding grounds. There, due in at least part the sub-adult steelhead (those fish a year from spawning) behave much like bull trout and sea-run cutthroat in north Puget Sound that also during the salt feeding near their home rivers. That is rather than spending the winter in the salt they return to nearby rivers (natal rivers?) to over-winter only to return to the salt the following spring for additional rearing before returning the following year to spawn for the first time.

Curt
 
Smalma said:
Pink Nighty-
Just to make things more confusing anglers often refer to those anadromous Chinook and coho that stay locally in Puget Sound rather than migrating to the open ocean as "residents" or sometimes in the case of those resident Chinook they are also called "blackmouth".

The case of the "half pounders' of southern Oregon/North California is pretty interesting. Rather than migrating towards the Gulf of Alaska as northern stocks of steelhead they take advantage of the nearby offshore cool upwelling called the Humboldt upwelling for their ocean feeding grounds. There, due in at least part the sub-adult steelhead (those fish a year from spawning) behave much like bull trout and sea-run cutthroat in north Puget Sound that also during the salt feeding near their home rivers. That is rather than spending the winter in the salt they return to nearby rivers (natal rivers?) to over-winter only to return to the salt the following spring for additional rearing before returning the following year to spawn for the first time.

Curt
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Fish are so fucking cool.
 
One of my best fishing buddies just also happened to be a fish biologist that first worked as a tech for ODF&W and then became the primary biologist of the Confederated Tribes of the Siletz ... which means he covers a lot of salmon, steelhead SRC fisheries. Needless to say, I picked up a lot of fish lingo from him.
 
Another twist--when bios are surveying anadromous zones of Puget Sound streams and observe adult non-anadromous O. mykiss, those fish are referred to and counted as "resident RBs" even though it's impossible to know just from a visual observation what their actual life history is/was, and they would likely be more accurately called "fluvial." So it's sort of a shorthand to distinguish them from anadromous mykiss, aka steelhead.
 
I sure am glad that I only fly fish and not worry what a fish us going to do after it hatches. My brain is cluttered enough from being 87. I just don't have anymore space to use with this thread. I'm just and old man that is waiting for something.
 
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Matt B said:
Another twist--when bios are surveying anadromous zones of Puget Sound streams and observe adult non-anadromous O. mykiss, those fish are referred to and counted as "resident RBs" even though it's impossible to know just from a visual observation what their actual life history is/was, and they would likely be more accurately called "fluvial." So it's sort of a shorthand to distinguish them from anadromous mykiss, aka steelhead.
Click to expand...

This is a good read regarding those "resident rainbows". Though a bit dated and only one river system, it shows how important they are.
SF

today.oregonstate.edu

Wild rainbow trout critical to health of steelhead populations

CORVALLIS, Ore. - Genetic research is showing that healthy steelhead runs in Pacific Northwest streams can depend heavily on the productivity of their stay-at-home counterparts, rainbow trout. Steelhead and rainbow trout look different, grow differently, and one heads off to sea while the other...
today.oregonstate.edu today.oregonstate.edu
 
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