Low water spawning

[salmo]

Not sure if I know what I’m talking about but, do low water conditions impact the late fall - winter spawn?

 

[wgmiller]

Here's a thread from 2010. Seems like the more things change, the more they stay the same.

 

[salmo]

I was a new member then.

 

[wgmiller]

I was a new member then.

My comment about things changing and staying the same was in reference to the cycle of low water and drought conditions. Didn't want you to think I was referencing the recurring question of how low water affects spawning 🙂

It appears there isn't a lot of research out there on exactly how low water levels impact trout spawning.

 

[jifigz]

This is just speculation, but I think low water conditions during spawning could impact trout in the following way:

Trout pick a suitable spawning location with the flows/oxygen level and substrate required during the spawn. If the trout builds a redd and spawn under low water conditions, those prime conditions could become poor quality locations if a large amount of rain makes the water level rise and the stream rage through the redd. If the water levels stay low, I bet the redds and eggs will thrive. The same is true for beds in high water. If they build beds in suitable places and then the water levels drop a ton, some of the beds might not even be under water anymore.

This is just speculation, though.

 

[afishinado]

This is just speculation, but I think low water conditions during spawning could impact trout in the following way:

Trout pick a suitable spawning location with the flows/oxygen level and substrate required during the spawn. If the trout builds a redd and spawn under low water conditions, those prime conditions could become poor quality locations if a large amount of rain makes the water level rise and the stream rage through the redd. If the water levels stay low, I bet the redds and eggs will thrive. The same is true for beds in high water. If they build beds in suitable places and then the water levels drop a ton, some of the beds might not even be under water anymore.

This is just speculation, though.

True above. One thing that can affect on spawning is the low water may not allow the trout to move to or trap them in their spawning areas. Shallow water may expose the trout to predators.

 

[esocidae]

One example I can think of is a large stream that can support trout year round, but they spawn in smaller tributaries with small cobble and gravel and little to no silt because the large streams don’t posses those characteristics. I’ll use Pine creek in the Tioga county stretch as an example. Big browns move into the tribs during fall when there is enough water. These tribs all have smaller wild browns and brookies. There is a huge difference in the amount of eggs produced by a 20” brown compared to a 10” brown.

During low water years like this few to none of these bruisers are able to make it to a suitable spawning location, and thus thousands upon thousands of eggs along with milt are wasted in Pine.

During higher water years, I’ve seen pods of browns in the 18-24” range moving upstream through the tribs like a small steelhead run.

 

[jifigz]

One more thing about the spawn that isn't necessarily related to the OP post, but spawning browns are a prime target for ospreys, eagles, and other raptors that prey on fish. I can only imagine it is even worse under super low and clear flows.

I am not lamenting the matter, as it is just an observation and the circle of life.

 

[esocidae]

Absolutely. The stream on my property has a small population of browns in it. Even during regular flows I’ve found half dead browns pecked on top of the head by blue herons. Every fall I see more blue herons, green herons, and kingfishers than any other time of the year. It’s like they know when it’s spawning time. That and I imagine they can smell the fish in shallow riffles. Usually I see the fish moving upstream at night, but a week or so with no rain during the run and the trout get hung out to dry in shallow water stretches where they become trapped.

 

[Nymph-wristed]

One more thing about the spawn that isn't necessarily related to the OP post, but spawning browns are a prime target for ospreys, eagles, and other raptors that prey on fish. I can only imagine it is even worse under super low and clear flows.

I am not lamenting the matter, as it is just an observation and the circle of life.

That was the only other thing I could add to the conversation from past observations (not science). There will be a lot more claw and beak wounds.

 

[rustbeltwilds]

Agree with all the above. I have also noticed the midstream rocks painted white by poop usually those are underwater now ..but not this year🤔