01-04-2020, 04:46 AM
Let me maybe help a little, as I remember previous discussion on a Montana study. I think the Montana study you are referring to is mentioned here in this review.
https://henrysfork.org/files/Rob%20Blog/...review.pdf
The study showed that hooking mortality goes way up when the water level temperature increases. Which is why in Montana, the Fish and Game will sometimes declare an emergency closure to some rivers during heat waves.
From the paper above.
"• The effects of elevated water temperatures on mortality rates was evaluated by Boyd, Horton,
Guy, and Leathe (2010) in a study of catch-and-release mortality of rainbow trout when daily
Catch-and-release mortality rates 3
maximum water temperatures were cool (<20ºC), warm (20-22.9ºC), and hot (≥23ºC). The
study took place at the Gallatin and Smith rivers.
o Catch-and-release mortality of rainbow trout increased when daily maximum water
temperature was higher than 20ºC.
o In the Smith River, mortality in hot conditions (𝑁𝑁 = 161) was 9%, mortality in warm
conditions (𝑁𝑁 = 53) was 8%, and mortality in cool conditions (𝑁𝑁 = 57) 0%.
o In the Gallatin River, mortality was 16% in hot conditions (𝑁𝑁 = 25) and 0% in coold
conditions (𝑁𝑁 = 48)."
The overall listed mortality rate for caught and released trout in cool water was between 3 and 4.5% (from the above paper). That covers most of our trout fishing here. That is also why almost every upper slot cutt from Strawberry has multiple battle wounds on them from many C&R events. They will survive most of them.
As for your personal preferences, I'm glad you are enjoying your meals and I too will take some fish home to eat from time to time. I'm not a C&R zealot like some folks. Additionally, many of our rivers need some additional harvest, so keep doing what you enjoy. Maybe hit the Middle or lower Provo and get a few more out of there too. They sure need it. [cool]
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https://henrysfork.org/files/Rob%20Blog/...review.pdf
The study showed that hooking mortality goes way up when the water level temperature increases. Which is why in Montana, the Fish and Game will sometimes declare an emergency closure to some rivers during heat waves.
From the paper above.
"• The effects of elevated water temperatures on mortality rates was evaluated by Boyd, Horton,
Guy, and Leathe (2010) in a study of catch-and-release mortality of rainbow trout when daily
Catch-and-release mortality rates 3
maximum water temperatures were cool (<20ºC), warm (20-22.9ºC), and hot (≥23ºC). The
study took place at the Gallatin and Smith rivers.
o Catch-and-release mortality of rainbow trout increased when daily maximum water
temperature was higher than 20ºC.
o In the Smith River, mortality in hot conditions (𝑁𝑁 = 161) was 9%, mortality in warm
conditions (𝑁𝑁 = 53) was 8%, and mortality in cool conditions (𝑁𝑁 = 57) 0%.
o In the Gallatin River, mortality was 16% in hot conditions (𝑁𝑁 = 25) and 0% in coold
conditions (𝑁𝑁 = 48)."
The overall listed mortality rate for caught and released trout in cool water was between 3 and 4.5% (from the above paper). That covers most of our trout fishing here. That is also why almost every upper slot cutt from Strawberry has multiple battle wounds on them from many C&R events. They will survive most of them.
As for your personal preferences, I'm glad you are enjoying your meals and I too will take some fish home to eat from time to time. I'm not a C&R zealot like some folks. Additionally, many of our rivers need some additional harvest, so keep doing what you enjoy. Maybe hit the Middle or lower Provo and get a few more out of there too. They sure need it. [cool]
[signature]