OldGobbler

OG Gear Store
Sum Toy
Dave Smith
Wood Haven
North Mountain Gear
North Mountain Gear
turkeys for tomorrow

News:

registration is free , easy and welcomed !!!

Main Menu

Genetic Stagnation

Started by Jimspur, July 07, 2021, 08:42:44 PM

Previous topic - Next topic

Jimspur

With all the threads lately about reasons for the decline of wild turkey
populations, I've seen it mentioned a couple of times that one of the
causes could be genetic stagnation. I've read a little about it, but I'm not
a biologist or a scientist.

I've thought long and hard about this, and of all the possible reasons
for the decline, this one seems to me to be the only one that could be
common to all turkey populations everywhere.

I would like to know what some of you who are biologists or scientists
think about this possibility, and what the rest of you think or know about
this.
                                                   


bbcoach

Jim, I've been thinking the same thing but I've been thinking about broods and poults.  The wild turkey has one of the TOUGHEST roads to hoe when it comes to survival.  If a hen lays 10 to 12 eggs and 2 make it maturity, we consider that a Success (yeah right).  With nests being ravaged, predation of poults, weather and numerous other survivability issues, how can we think that the wild turkey can survive much less build bigger numbers?   

Jimspur

Quote from: bbcoach on July 07, 2021, 09:19:49 PM
Jim, I've been thinking the same thing but I've been thinking about broods and poults.  The wild turkey has one of the TOUGHEST roads to hoe when it comes to survival.  If a hen lays 10 to 12 eggs and 2 make it maturity, we consider that a Success (yeah right).  With nests being ravaged, predation of poults, weather and numerous other survivability issues, how can we think that the wild turkey can survive much less build bigger numbers?

Ron, I agree with what you're saying. I'm just wondering if they were
more genetically diverse would that increase the number of poults that survive, or even hatch out. In other words make the hatching rate better,
and the survival rate better.

GobbleNut

There are two terms regarding the impacts of genetics in turkey populations that probably should be discussed.  One is genetic stagnation.  The other that should be talked about is "hybrid vigor". 

Personally, I doubt genetic stagnation is a major player in turkey population declines.  Unless a turkey population consists of a low numbers of either native birds or transplants,...and that population is geographically isolated from other turkey populations,...a decline in numbers due to a lack of genetic diversity is unlikely.  I suspect there are few, if any, turkey populations that fit both of those parameters.

Hybrid vigor, and it's impacts on turkey population viability is another matter.  Simply stated, intergradations of subspecies that genetically intermix with each other have been shown to survive/thrive better than non-intermixed subspecies.  Of course, the issue of subspecies purity comes into play when talking about wild turkeys and there is a understandable reluctance to introduce new subspecies into regions that are thought to consist of single, genetically-pure subspecies. 

However, there are many areas of the country where hybridization is common, even in some populations that are generally thought to be pure.  Introducing new genetics into those types of areas could indeed result in population increases IF genetic stagnation is thought to be an issue.

Finally, even in known populations of pure subspecies, introducing geographically-distant genetics from the same subspecies can have similar impacts as hybrid vigor.  For instance, introducing genetics from Eastern wild turkeys from the northeastern states might have positive impacts on turkey numbers in, say, Arkansas, Louisiana, or other southeastern states.  I would assume that wildlife biologists are considering all of the above in their approach to implementing strategies to reverse turkey population declines.  If they aren't, they should be...

Meleagris gallopavo

Quote from: GobbleNut on July 08, 2021, 09:01:10 AM
There are two terms regarding the impacts of genetics in turkey populations that probably should be discussed.  One is genetic stagnation.  The other that should be talked about is "hybrid vigor". 

Personally, I doubt genetic stagnation is a major player in turkey population declines.  Unless a turkey population consists of a low numbers of either native birds or transplants,...and that population is geographically isolated from other turkey populations,...a decline in numbers due to a lack of genetic diversity is unlikely.  I suspect there are few, if any, turkey populations that fit both of those parameters.

Hybrid vigor, and it's impacts on turkey population viability is another matter.  Simply stated, intergradations of subspecies that genetically intermix with each other have been shown to survive/thrive better than non-intermixed subspecies.  Of course, the issue of subspecies purity comes into play when talking about wild turkeys and there is a understandable reluctance to introduce new subspecies into regions that are thought to consist of single, genetically-pure subspecies. 

However, there are many areas of the country where hybridization is common, even in some populations that are generally thought to be pure.  Introducing new genetics into those types of areas could indeed result in population increases IF genetic stagnation is thought to be an issue.

Finally, even in known populations of pure subspecies, introducing geographically-distant genetics from the same subspecies can have similar impacts as hybrid vigor.  For instance, introducing genetics from Eastern wild turkeys from the northeastern states might have positive impacts on turkey numbers in, say, Arkansas, Louisiana, or other southeastern states.  I would assume that wildlife biologists are considering all of the above in their approach to implementing strategies to reverse turkey population declines.  If they aren't, they should be...
Nailed it!   


Sent from my iPhone using Tapatalk
I live and hunt by empirical evidence.

silvestris

There are, other than morality, reasons that breeding between brothers and sisters is frowned upon, genetics being among them.
"[T]he changing environment will someday be totally and irrevocably unsuitable for the wild turkey.  Unless mankind precedes the birds in extinction, we probably will not be hunting turkeys for too much longer."  Ken Morgan, "Turkey Hunting, A One Man Game

Jimspur

#6
I hope biologists are at least considering it as a possibility. I do doubt
that this could happen in a free-ranging population of wild turkeys.
The hybrid vigor is interesting, but would probably get push back because
hunters don't want their populations hybridized.


Jim K

I love this forum. I love learning things about turkeys I didn't know before. These type threads are great. Thanks fellas!

WV Flopper

  No. Don't agree.

Maybe, relocation could bring in new blood with different antibodies to disease that could help a population?

Maybe, the new blood would bring in new disease that residents don't have antibodies too?

We have in the U.S., REBUILT State populations with minimal transfer birds, REBUILT! With a turkeys life cycle at 3-5 years we are now saying after 15 or so generations they are stagnant? No. Don't Agree.

I am not a Biologist and don't pretend to be, just a turkey hunter that is older than a few generations of these turkeys. I remember when WV traded turkey to Tennessee for Otter. We have several Otter in my local waters, thanks to our turkeys.
 

GobbleNut

Quote from: WV Flopper on July 08, 2021, 08:45:01 PM


Maybe, relocation could bring in new blood with different antibodies to disease that could help a population?
Maybe, the new blood would bring in new disease that residents don't have antibodies too?

We have in the U.S., REBUILT State populations with minimal transfer birds, REBUILT! With a turkeys life cycle at 3-5 years we are now saying after 15 or so generations they are stagnant? No. Don't Agree.

Your concerns expressed here are valid.  That is why bloodwork/testing should be done when transplanting birds to ascertain as much as possible whether the potential exists for introduction of diseases from relocated birds to existing populations.  However, the concept of hybrid vigor and/or the introduction of new genetics is a proven concept in invigorating wildlife populations. Yes, it should not be done haphazardly, but there are ways of addressing the concerns you have raised. 

As has been stated previously, I also agree that genetic stagnation is probably not a significant issue in the vast majority of wild turkey populations.  Having said that, the reality is that we appear to have severely declining turkey populations in some areas of the country.  I am of the opinion that nothing should be taken off the table in terms of addressing those declines.  Introduction of new genetics is just one of the possibilities and should not just be summarily discounted. 

Furthermore, recovery of populations is also a direct function of numbers of breeding birds you have on the landscape when conditions are favorable for reproductive success.  Even if we remove the concept of genetic invigoration from the equation, the potential for recovery of any given population will invariably be correlated to numbers of adult birds (obviously skewed towards hen numbers) available to breed.  If for no other reason, THAT is why having resources in place for trap and transfer programs, when needed, should be high on the list of options for recovering turkey numbers.  The genetic diversification in play is just a potentially significant added bonus. 

And finally, none of this is to say that translocating turkeys is the end-all solution to the problem.   It is just a tried and true method of restoring turkey numbers when and where needed.  The real, and probably widely varied, reasons for turkey population declines must be identified and addressed first and foremost. 

Jimspur

Quote from: warrent423 on July 10, 2021, 09:37:42 AM
"Pets" will, for the most part, continue to breed "pets" ;)

Which parts of what states do you consider to have "real gobblers"?

Meleagris gallopavo

It's difficult for me to find relevant articles for this discussion without having a paid subscription.  But here are some abstracts from scientific papers as well as a full article on the subject.  The take home that I got from this is that wild turkey genetic diversity is different based on where you are, but overall the genetic bottlenecks from inbreeding are infrequent.  The tools are there to monitor turkey population genetics but larger studies are needed to understand the dynamics of habitat influences.

https://www.jstor.org/stable/3672828

https://wildlife.onlinelibrary.wiley.com/doi/abs/10.1002/jwmg.575

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1056&=&context=tnas&=&sei-redir=1&referer=https%253A%252F%252Fscholar.google.com%252Fscholar%253Fhl%253Den%2526as_sdt%253D0%252C47%2526qsp%253D16%2526q%253Dwild%252Bturkey%252Bpopulations%252B%252522influence%252Bof%252Bfragmentation%252522%2526qst%253Dbh#search=%22wild%20turkey%20populations%20influence%20fragmentation%22

https://www.jstor.org/stable/3809684

https://www.researchgate.net/profile/Emily-Latch/publication/228633736_The_use_of_molecular_markers_in_wild_turkey_management/links/00b4951cb46ed65c8d000000/The-use-of-molecular-markers-in-wild-turkey-management.pdf


Sent from my iPhone using Tapatalk
I live and hunt by empirical evidence.

Neill_Prater

No biologist here, just try to use a little common sense. I don't know that genetic stagnation is a factor in the population decline anywhere, but my guess is that it may be a factor in the inability of isolated populations to rebound to healthier levels.

I've hunted SE Kansas since around 1990 and was fortunate enough to obtain permission to hunt a small farm my first time out there, and have maintained that friendship to the present time. A creek flows diagonally across the property, and in those days, was loaded with birds. But then, almost every property with water and a patch of timber was loaded with turkeys, as was the public land in that portion of the state.

I talked to a game Warden my second time out there, and he told me that there had always been a few turkey in the area but some time in the late 70's early 80's, if I recall correctly, trapped birds were released and within a few short years, turkeys were everywhere.

Many times I never got around to hunting my friends farm because I would tag out on public first. When I did, there was generally a flock of as many as two dozen birds frequenting his property and ranging up the creek onto a neighbor where I could also hunt.

I began to notice a decline in the population around 2004 or 2005. Still plenty of turkey, but not as many on the farm, or on the public areas in the vicinity. In the late 90's, I, more than once, observed flocks of more than 30 jakes. On the farm, instead of a half dozen gobblers, there might be 3 or 4 in residence.

In 2007, in, I think late May or early June, the area experienced torrential rain. I was told 13 inches overnight. Lake levels on the public land rose many feet in a very short time. The next year, I only saw one hen in an entire day of hunting. I had to return home due to a death in the family, and didn't hunt the area again that season, or for the next 3 or 4 years.

When I contacted my farmer friend a few years later, he told me he was seeing a few birds, so I began hunting there again each Spring. With the exception of one year, when I was lucky enough to bag one bird on public near there, I tagged out on the property every season until this year. Most years there would be 2 or 3 adult gobblers and maybe a half dozen hens in the area.  I usually hunted after our season ended, do the majority of the birds I killed in the month of May.

In 2020, the limit was one bird and there were 3 gobblers running together. I only saw 2 hens. The gobbler I killed, probably a 2 year old, was very light, maybe 14 lbs, unusual for the area. This year, when I contacted the landowner I was shocked when he told me he hadn't seen a single turkey on his property, or in the area!

My thinking is that perhaps the population had decreased to such a low point that, for whatever reason, reproduction just could no longer sustain a viable population. Anyone who has hunted Kansas knows that it isn't a landscape of continuous good habitat, but rather one of pockets of great habitat often separated by miles of open country. I think when the population is high, birds continuously move from one area to the other, keeping the gene pool fresh, but when you only have a few birds, that migration doesn't happen.

Sent from my moto z4 using Tapatalk


Jimspur

Quote from: warrent423 on July 10, 2021, 12:10:33 PM
Quote from: Jimspur on July 10, 2021, 10:54:41 AM
Quote from: warrent423 on July 10, 2021, 09:37:42 AM
"Pets" will, for the most part, continue to breed "pets" ;)

Which parts of what states do you consider to have "real gobblers"?
Surely you can figure that one out for yourself.

I learned from some of your previous posts that you consider the
googan-educated, ridge-running longbeards of the South Cherokee
to be "real gobblers". I would also like to know if you have found
other states, or areas within other states that have gobblers as smart
and well-educated as those in the South Cherokee.



saltysenior


   They are treating this as a problem with the decline of the Florida Scrub Jay....captured birds are being moved to far off habitat..