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CWD could kill the deer herd in 41 years!

BSK said:
Hmmm, a whole lot of critical information not in the article (although it might be in the candidate's dissertation). What is the total adult annual mortality rate? What are all of the causes? How much is hunting increasing mortality? What are the fawn production and survival rates (fawn recruitment rate)? How much immigration and emigration occurs annually?

This is a study of a fairly isolated pocket population. Most whitetail populations don't have that problem. In addition, as AT Hiker pointed out, Mule Deer are a very touchy species. Their populations are nowhere near as robust as whitetails and are highly susceptible to changes in mortality. On the other hand, whitetails are one of the most robust large mammal species known. They're like cockroaches: once you have them, they're virtually impossible to get rid of. They survive well in nearly any environment they are relocated into.

One other critical factor for whitetails is genetic diversity. I've posted many times about how genetically diverse whitetail populations are. They may be the most genetically diverse mammal known. It is my belief their social structure and breeding process creates this genetic diversity and is why they are such a successful species. Place a group of whitetails in any environment and just by shear random chance (due to extreme genetic diversity) some of those individuals will be genetically adapted to the environment. In the posted article they discussed the different gene allele sequences. They said there were 3 in the local mule deer population, and three in a studied elk population. Last I read, there are actually 6 known for all elk, with one potentially immune to CWD. And of my last reading of the data, because whitetails are so genetically diverse, researchers had found 83 variations of that allele in whitetails! Out of 83 variations, some will be immune. That's the way genetic diversity and Natural Selection works.
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So in a nutshell, it's basically impossible whitetails could go extinct due to CWD if I'm reading this correctly?

I had to put on my thinking cap to follow all this. 🤣
 
UCStandSitter said:
So in a nutshell, it's basically impossible whitetails could go extinct due to CWD if I'm reading this correctly?

I had to put on my thinking cap to follow all this. 🤣
Click to expand...
Not sure of the studies depth, but scrapie resistant prion proteins (CWD basically bends these and the build up of them causing death) have been compared to resistant cervids and suggest mutations can/do exist that could provide some protection. Whitetail are more likely to possess these alleles vs mule deer, though it seems.
Another study that inoculated CWD into deer with known alleles found that the deer with the resistant allele lived about a 3 years longer than the deer without the resistant allele (approx 1.5 years before death).
Do this provide potential evolution of protein resistant genotypes or is this just natures way of slowing the spread?

As a simpleton here, my opinion is nature will once again reign champion… question is how long will it take?
 
AT Hiker said:
Mule deer have it rough, everything from weather, predators and loss of habitat is trying to kill them…it's a delicate resource and CWD makes it that more dire.

The good news;
CWD doesn't seem to impact females getting pregnant and fawning, allowing the possible resistant gene to evolve throughout the herd.
Whitetail are not mule deer (which most cited studies seem to be on mule deer). Whitetail seem to be crafty little critters that can survive in some wild situations, unlike sensitive muleys.
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I did my senior thesis on changes in Mule Deer genetics as a result of hunter and predatory pressure.

I grew up hunting them out West (New Mexico) and was always fascinated with the challenges that ole Odocoileus hemionus faced. (That's probably the only scientific name I can remember from college)

I wonder if I held on to that paper somewhere. Haven't seen it in 20 years and that old PC is long gone.
 
AT Hiker said:
Not sure of the studies depth, but scrapie resistant prion proteins (CWD basically bends these and the build up of them causing death) have been compared to resistant cervids and suggest mutations can/do exist that could provide some protection. Whitetail are more likely to possess these alleles vs mule deer, though it seems.
Another study that inoculated CWD into deer with known alleles found that the deer with the resistant allele lived about a 3 years longer than the deer without the resistant allele (approx 1.5 years before death).
Do this provide potential evolution of protein resistant genotypes or is this just natures way of slowing the spread?

As a simpleton here, my opinion is nature will once again reign champion… question is how long will it take?
Click to expand...
The sheer size of the whitetail population bodes well for the future of deer hunting.

There are about 10X the number of Whitetails as Mule Deer.
 
AT Hiker said:
Not sure of the studies depth, but scrapie resistant prion proteins (CWD basically bends these and the build up of them causing death) have been compared to resistant cervids and suggest mutations can/do exist that could provide some protection. Whitetail are more likely to possess these alleles vs mule deer, though it seems.
Another study that inoculated CWD into deer with known alleles found that the deer with the resistant allele lived about a 3 years longer than the deer without the resistant allele (approx 1.5 years before death).
Do this provide potential evolution of protein resistant genotypes or is this just natures way of slowing the spread?

As a simpleton here, my opinion is nature will once again reign champion… question is how long will it take?
Click to expand...
I'd agree with that take, natural selection will see to it the deer with immunity become the dominant breeding group and the "weaker" parts of the heard thin out thereby eradicating the disease.
 
If CWD were going to wipe out entire cervid species, then why do we still have sheep? Scrappie in sheep is where CWD comes from and has been known for 1,000 years (literally). Because over hundreds and hundreds of years, sheep have developed defenses against Scrappie. Nature always finds a way.
 
BSK said:
Hmmm, a whole lot of critical information not in the article (although it might be in the candidate's dissertation). What is the total adult annual mortality rate? What are all of the causes? How much is hunting increasing mortality? What are the fawn production and survival rates (fawn recruitment rate)? How much immigration and emigration occurs annually?

This is a study of a fairly isolated pocket population. Most whitetail populations don't have that problem. In addition, as AT Hiker pointed out, Mule Deer are a very touchy species. Their populations are nowhere near as robust as whitetails and are highly susceptible to changes in mortality. On the other hand, whitetails are one of the most robust large mammal species known. They're like cockroaches: once you have them, they're virtually impossible to get rid of. They survive well in nearly any environment they are relocated into.

One other critical factor for whitetails is genetic diversity. I've posted many times about how genetically diverse whitetail populations are. They may be the most genetically diverse mammal known. It is my belief their social structure and breeding process creates this genetic diversity and is why they are such a successful species. Place a group of whitetails in any environment and just by shear random chance (due to extreme genetic diversity) some of those individuals will be genetically adapted to the environment. In the posted article they discussed the different gene allele sequences. They said there were 3 in the local mule deer population, and three in a studied elk population. Last I read, there are actually 6 known for all elk, with one potentially immune to CWD. And of my last reading of the data, because whitetails are so genetically diverse, researchers had found 83 variations of that allele in whitetails! Out of 83 variations, some will be immune. That's the way genetic diversity and Natural Selection works.
Click to expand...
Something similar appears to occur with EHD. While EHD can wipe out 50% of a local white tailed deer population (or more?), the survivors have immunity. EHD is a virus, not a Mis-folded protein, so it's immunity via antibodies not genetic immunity in the survivors. This is why it's rare to have back-to-back EHD years locally, as the survivors have immunity.

Heard this on the Jan 3 MeatEater podcast by Jim Heffelfinger, wildlife biologist. A good listen and they cover a lot ground on EHD, CWD, and other "Things That are not Sexy to Talk About." Rinella somewhat wisecracked that if herd reduction is the solution to CWD (not sure if that's his view), but he did make a wisecrack that then will EHD help save the southeast's deer from CWD?
 
BSK said:
because whitetails are so genetically diverse, researchers had found 83 variations of that allele in whitetails! Out of 83 variations, some will be immune.
Click to expand...
is this not sound evidence to let this thing run its course? Artificial thinning also reduces the number of potential immune breeders based on this.
 
AT Hiker said:
….Furthermore, fawns produced by CWD-negative deer, which more likely possessed the more resistant genotype compared to CWD-positive deer in our study, potentially contributed to the increase of the F allele in the population….."
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I was about to suggest this. Is it possible that the slow progress of the disease will give more time for resistant genetics to populate the herd?
 
BSK said:
That is how natural immunity to almost all communicable diseases works.
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The problem with this theory on CWD is that infected deer can continue to breed and reproduce. If they couldn't it would hasten this process.
 
Managing a deer herd for CWD is not a set it and forget it process. As the disease progresses and moves across the state, the goals could change from slowing the spread to maintaining the herd. I expect we will see rule changes down the road. What nobody knows is how CWD will affect our southern deer herd.
 
Speedwell-Hunter said:
curious why its ravaging western states. Poor dutton ranch and the likes of those
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If they knew then we wouldn't be having this discussion, but if I had to guess it probably seems worse because population density and the species out west are more susceptible according to earlier posts.
 

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