From "Meat-eater" 5/26 Can Large Predators Control CWD

[Mustangs Rule]

I just came across this relatively recent article from meateater about large predators controlling CWD.

It is a good article, long but worthy of the read. I would offer the topic open for discussion to anyone who read it, it does offer new info.

Can Large Carnivores Control CWD?

No one needs an introduction to chronic wasting disease (CWD) at this point, or the recounting of its history and incurable nature. It is now found in 37 states and its footprint in some locations is growing. The disease is not caused by a bacteria or virus, but by a prion (“PREE-on”), a type of...

www.themeateater.com

 

[Bhoesl]

You’re right, it is a long article, and I’ll admit I usually despise anything written by rinella. My limited understanding of prions is that almost nothing can kill them, so I would be skeptical of the claim that they are not being spread more in the feces of the predators.

 

[Mustangs Rule]

You’re right, it is a long article, and I’ll admit I usually despise anything written by rinella. My limited understanding of prions is that almost nothing can kill them, so I would be skeptical of the claim that they are not being spread more in the feces of the predators.

I know what you mean about Rinnella Inc. He is the Elvis of Hunting.

The relatively recent Mountain Lion prion study, which I believe was done by the Wyoming F and Game, or maybe the University of Wyoming, was conclusive. Mountain Lions are immune to CWD and their body chemistry typically totally destroys about 96.5 % of active prions consumed and the remaining 3.5% that are "alive" are pooped out quickly.

Scoring an "A +" on prion destruction with a one-time localized single poop-out they are not considered to be spreaders of CWD. Quite the opposite really.

I know of no such study on Wolves or coyotes. I will look for one. Getting that info would be so critical to this jigsaw puzzle.

Birds and reptiles like alligators are immune to CWD but their body chemistry does not denature prions.

 

[brockel]

Montana should be a prime example of “controlling” CWD. VERY liberal hunting seasons and bag limits and plenty of predators. Yet CWD continues to spread. CWD is going to do what CWD does

 

[Mustangs Rule]

This is a study done 11 years ago on coyote's body chemistry denaturing CWD Prions. It is qualitative not quantitative. All it does is state that active CWD prions get pooped out in coyotes.

What makes the Mt. Lion study/CWD-Prion Study so valuable is how numbers based it is. Do mountain lions poop out active CWD prions, yes, but only to the 4% level of how much they ate. 96 % of the CWD prions were denatured.

I wish we could get quantitative CWD-prion decomposition rates for both wolves and coyotes.

I used to live in Wyoming, First in SE Wyoming then in NW Wyoming. THe relationship between large predators, and % CWD was telling.

In SE Wyoming the CWD infection rate for deer hit 43%, no resident wolf populations. The Grey Bull River area CWD deer rate is 60% with no wolves.

The Jackson Area of Wyoming CWD rate is currently 10%, and the Wind River range has gone from 0% in the not-too-distant past to 10% CDW now. Both of these last two areas have been both wolf and lion heavy for many decades and also loaded with winter elk feeding grounds which are CWD and Elk hoof rot breeding grounds.

CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans) - PMC

Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually ...

pmc.ncbi.nlm.nih.gov

 

[Mustangs Rule]

And also, there are some basic principles of immunity that certain animals have to diseases. Immunity usually does not happen by accident; it happens by prolonged exposure over time to pathogens.

That all these predators and scavengers have complete immunity to CWD prions is incredibly significant.

Again, such things do not happen by accident.

 

[brockel]

I used to live in Wyoming, First in SE Wyoming then in NW Wyoming. THe relationship between large predators, and % CWD was telling.

In SE Wyoming the CWD infection rate for deer hit 43%, no resident wolf populations. The Grey Bull River area CWD deer rate is 60% with no wolves.

The Jackson Area of Wyoming CWD rate is currently 10%, and the Wind River range has gone from 0% in the not-too-distant past to 10% CDW now. Both of these last two areas have been both wolf and lion heavy for many decades and also loaded with winter elk feeding grounds which are CWD and Elk hoof rot breeding grounds.

CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans) - PMC

Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually ...

pmc.ncbi.nlm.nih.gov

Do you happen to know the deer populations for those areas?

 

[SerialScience]

This is a study done 11 years ago on coyote's body chemistry denaturing CWD Prions. It is qualitative not quantitative. All it does is state that active CWD prions get pooped out in coyotes.

What makes the Mt. Lion study/CWD-Prion Study so valuable is how numbers based it is. Do mountain lions poop out active CWD prions, yes, but only to the 4% level of how much they ate. 96 % of the CWD prions were denatured.

I wish we could get quantitative CWD-prion decomposition rates for both wolves and coyotes.

I used to live in Wyoming, First in SE Wyoming then in NW Wyoming. THe relationship between large predators, and % CWD was telling.

In SE Wyoming the CWD infection rate for deer hit 43%, no resident wolf populations. The Grey Bull River area CWD deer rate is 60% with no wolves.

The Jackson Area of Wyoming CWD rate is currently 10%, and the Wind River range has gone from 0% in the not-too-distant past to 10% CDW now. Both of these last two areas have been both wolf and lion heavy for many decades and also loaded with winter elk feeding grounds which are CWD and Elk hoof rot breeding grounds.

CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans) - PMC

Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually ...

pmc.ncbi.nlm.nih.gov

Great findings if you want fodder for the “eliminate hunting predators will fix it all” viewpoint.

 

[IDiot]

And also, there are some basic principles of immunity that certain animals have to diseases. Immunity usually does not happen by accident; it happens by prolonged exposure over time to pathogens.

That all these predators and scavengers have complete immunity to CWD prions is incredibly significant.

Again, such things do not happen by accident.

CWD is not a pathogen. It does not act like a pathogen such as a virus or bacteria that an immune system recognizes and fights off. It's more analogous to a lock and key. The wrong kind of key won't fit in the lock. CWD doesn't go to work replicating in a system that can't accept it. The immune system isn't involved in CWD infections.
There are examples of prion diseases jumping the species barrier such as mad cow jumping to humans. Not common but can happen, most prion diseases are species specific. I actually think there is a lot of merit to the theory that CWD arose from housing captive deer along side scrape positive sheep. Scrape is a prion disease found in sheep.

 

[44hunter45]

Geriatric Opinion alert!

If this science says apex predators CAN control CWD, maybe the question is, "Why aren't they?"

I'm just a marginally well-read idiot. I'm not taking any victory laps on this science. The cited study is 11 years old? @Hunting Wife , is there anything here to get excited about?

As far as fodder for the anti-predator hunting crowd: California is still the favored test case for ending sport hunting of predators.
People use science that justifies their worldview. Sometimes they even distort it to fit.

One needs to broaden scope before making a conclusion based on one published study.

As an example:
One 2020 study concluded that California human/livestock incidents since Prop 117 were on par or less than comparable western states which allow sport hunting.(BTW - I can find no data in this study on cougar mortality via depredation permit kills.
https://www.researchgate.net/publication/339248912_The_Elephant_in_the_room_What_can_we_learn_from_California_regarding_the_use_of_sport_hunting_of_pumas_Puma_concolor_as_a_management_tool

Another study from 2023 concluded that human caused cougar kills in California continue to rise significantly since Prop 117. Their analysis showed that the largest human caused mortality rate is depredation permit kills.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10068828/

It kind of makes me wonder which "peers" reviewed the first study. Why ignore a major mortality vector?
Yes, the NIH study came later, but there was ample mainstream and social media coverage of the idea that "professional" cougar kills had replaced "sport" kills in California. This is actually a misrepresentation as well. USDA-WS did kill cats in California, but the livestock depredation loophole to Prop 117 allows livestock producers to apply for kill permits. So not all the cats killed since Prop 117 are USDA-WS kills, but include citizen kills on "non-sport" permits.

Since both depredation hunts and sport hunts employ the same methods, what is really the difference? I suggest it may be the hated word, "sport".

My point is that most anyone can find a study to say what they want to say. To use a metaphor that may upset the pure scientists, the truth is in the "Whole Counsel" of the canon of peer reviewed work.

 

[MTLabrador]

In my humble opinion the idea of predators controlling CWD is a joke. In the CWD hotbed of central, SE, and NE Wyoming there’s no shortage of lions. One could also say the data says that humans are super predators that are immune to CWD…