Lost the post spawn battle?

[mute]

Found this poor pool boss on the bottom of the stream bed. Hoping he just lost the war with the spawn and it wasn't influenced by other unnatural causes. Speaking of which, does anyone know of any data sheets out there or metrics on expected probabilities of fish like this dieing after the spawn?

 

[FarmerDave]

consider this a bump.

I was hoping a biologist would respond to this because I think it is an interesting question. Are you out there, Mike?

Trout expend quite a bit if energy during the spawn, which is one of the reasons I don't fish for them during the spawn. I read somewhere that first time spawners expend less energy and experience very little loss. But for repeat spawners, the survival rate for spawning stream bred brown trout can be as low as 65% for males and about 50% for females. For hatchery raised trout, the survival rate is lower.

Disclaimers: I am not a biologist so I could be wrong. The numbers I provided might have been for sea or lake run trout. I can't remember for sure.

 

[hooker-of-men]

I assume it got exhausted from killing too many brook trout.

 

[mute]

I assume it got exhausted from killing too many brook trout.

So we're on the same page then that the best worth of efforts, money and resources here would be to kill every wild brown trout we come across right?

 

[mute]

consider this a bump.

I was hoping a biologist would respond to this because I think it is an interesting question. Are you out there, Mike?

Trout expend quite a bit if energy during the spawn, which is one of the reasons I don't fish for them during the spawn. I read somewhere that first time spawners expend less energy and experience very little loss. But for repeat spawners, the survival rate for spawning stream bred brown trout can be as low as 65% for males and about 50% for females. For hatchery raised trout, the survival rate is lower.

Disclaimers: I am not a biologist so I could be wrong. The numbers I provided might have been for sea or lake run trout. I can't remember for sure.

Thats interesting. Are you aware of any articles, books, etc where more information can be read about these types of topics? I struggle finding information about stuff like that that interests me. Along with the migrating efforts\tendencies of these fish in our waterways and everything about it.

 

[silverfox]

Thats interesting. Are you aware of any articles, books, etc where more information can be read about these types of topics? I struggle finding information about stuff like that that interests me. Along with the migrating efforts\tendencies of these fish in our waterways and everything about it.

Generally, because they're not some ecologically important species here. You'll find studies on S. trutta in Italy, Germany, Iceland, etc. though. Those same behaviors would apply to the species in the United States. Just don't expect scientists in the United States to expend a lot of energy studying introduced species other than to better understand their ecological impact in their introduced environment or to broadly understand fish behavior in general.

 

[Mike]

Have never seen a scientific paper that I recall relating to post-spawning mortalities of BT, ST, or RT, but at that size/age in Pa mortalities are expected to be fairly common. Such fish are close to the end of their natural lives and have contributed multiple times to the gene pool. You were fortunate to find that fish before it decomposed or was consumed by a scavenger.

I only ever found one large post-spawn BT despite the time that I spent in the field doing unassessed wild trout stream surveys in Nov and Dec during the last few yrs of my career. The one that I did find was a late December trophy wild BT in Mill Ck, trib to the Codorus, in York City. It was on its side, nearly dead, so timing was perfect. As a side note, mortality occurs in other seasons too, but when water is warmer decomposition is faster so you have less chance of finding single dead fish.

 

[Swattie87]

So we're on the same page then that the best worth of efforts, money and resources here would be to kill every wild brown trout we come across right?

That is the majority opinion around here, yes. If you don’t like it, may I suggest a spincasting forum instead?

On a serious note, that fish doesn’t appear to be spent from spawning or obviously “spawned out” to me. It still has pretty good body mass. Who knows what killed it, but I wouldn’t assume it was dead from spawning activity. Most big dead Browns I’ve seen like that have evidence of attempted predation by herons.

 

[mute]

That is the majority opinion around here, yes. If you don’t like it, may I suggest a spincasting forum instead?

On a serious note, that fish doesn’t appear to be spent from spawning or obviously “spawned out” to me. It still has pretty good body mass. Who knows what killed it, but I wouldn’t assume it was dead from spawning activity. Most big dead Browns I’ve seen like that have evidence of attempted predation by herons.

I glued some feathers onto my rapala and i treat it like a streamer. No need to use any more of spinning gear
You make a far point, i tried to get a close up of its head\side place where it had tons of scratch\line marks. But i feel like that also happens from fishing line being wrapped around their heads, so maybe foul plan was apart of this fishes live, i dont know.

There has been a large abundance of heron activity on this stream this year however a well but i did not see any wounds on this fish.

 

[FarmerDave]

Thats interesting. Are you aware of any articles, books, etc where more information can be read about these types of topics? I struggle finding information about stuff like that that interests me. Along with the migrating efforts\tendencies of these fish in our waterways and everything about it.

Yea, I struggled, too. Otherwise I would have provided link(s). I did find a little bit. If a biologist does not speak up, I'll give it another shot.

 

[FarmerDave]

I see that Mike did respond, so I took another shot. I did find the abstract from an article that was published in Canada. This looks like where I got my numbers, either directly or indirectly. But being a cheap bastard, there is no way I am paying $40 to get the full article.

Energetics and survival of virgin and repeat spawning brown trout (Salmo trutta)

I did find the same article elsewhere, but when I tried to download the PDF, it was downloading an executable, so I stopped the download. I'm not a computer weenie, so I felt it wasn't worth it. If anyone else wants to give it a shot, just do a google search on the title. But I don't recommend downloading an .exe file from a source that you are not familiar with.

 

[Nymph-wristed]

Have never seen a scientific paper that I recall relating to post-spawning mortalities of BT, ST, or RT, but at that size/age in Pa mortalities are expected to be fairly common. Such fish are close to the end of their natural lives and have contributed multiple times to the gene pool. You were fortunate to find that fish before it decomposed or was consumed by a scavenger.

I only ever found one large post-spawn BT despite the time that I spent in the field doing unassessed wild trout stream surveys in Nov and Dec during the last few yrs of my career. The one that I did find was a late December trophy wild BT in Mill Ck, trib to the Codorus, in York City. It was on its side, nearly dead, so timing was perfect. As a side note, mortality occurs in other seasons too, but when water is warmer decomposition is faster so you have less chance of finding single dead fish.

That's a great point about air and water temp. I do see more dead fish in the winter, but the reason why is more complicated than post-spawn death in this case.

 

[mute]

I see that Mike did respond, so I took another shot. I did find the abstract from an article that was published in Canada. This looks like where I got my numbers, either directly or indirectly. But being a cheap bastard, there is no way I am paying $40 to get the full article.

Energetics and survival of virgin and repeat spawning brown trout (Salmo trutta)

I did find the same article elsewhere, but when I tried to download the PDF, it was downloading an executable, so I stopped the download. I'm not a computer weenie, so I felt it wasn't worth it. If anyone else wants to give it a shot, just do a google search on the title. But I don't recommend downloading an .exe file from a source that you are not familiar with.

Not the full thing, but i got more then that and uploaded it here.

https://fishyintentions.com/Energetics_and_survival_of_virgin_and_re.pdf