Dr. Kroll, MDNR & Turtle Lake Club results

[DEERSLAYER]

I received this as a QDMA membership mailing. I thought some of you may find it interesting and decided to pass it along

Turtle Lake Club Winter Health Check

I had the unique privilege recently to attend the winter health check conducted at Turtle Lake Club by Dr. Kroll and his team. Turtle Lake is a contiguous land mass consisting of approximately 27,000 acres and is located in Hillman Michigan at the epicenter of the tuberculosis outbreak in Northeast Michigan. This is the 6th year that the team has conducted their winter health check and from what I understand Dr. Kroll will begin to reveal some of his findings now that there are several years of scientific data available and trends have been established. I was very impressed with how efficient the team was at collecting the critical data that they were looking for and how they worked in concert with Dr. Schmitt, our DNR Veterinarian who was also present gathering data to conduct disease management tests.

Not unlike other activities that I have participated in recently, such as Tony Lapratt’s whitetail boot camp – I participated thinking that I knew quite a bit about the subject matter but kept an open mind as to what I might learn. Both experiences really helped me tie everything together and understand the big picture, as well as identify the tools that are necessary to achieve it.

Here are some of the things that I witnessed and learned from my experience.
1) The folks tasked with harvesting the does that were to be used during the necropsy were asked to harvest mature does and shoot them in the neck to avoid destroying the data. The entire time I was there no mistakes were made even though the majority of bucks have lost their antlers prior to mid February. No bucks or even nubbin bucks – just mature does between 2.5 and 6.5+ years old were brought in. Yet, how often do we hear about hunters who do not want to adopt programs such as AR’s because it is so difficult to identify specific deer. It is very possible, but shooting at running deer crossing a field or moving through dense forest isn’t an acceptable harvest method for a true deer hunter/manager.
2) Dr. Kroll and the staff notated where on the property every deer was harvested. Once all the data is collected and individual deer health trends determined, decisions on where habitat improvement is necessary can be developed. How powerful is that?
3) Turtle Lake has experienced a lower overall prevalence rate for TB as the study has progressed, although the club is located in the core area of the TB Zone. There have been positive TB deer identified in the past and many of those in recent years have been located on the fringe areas of the property. The thought is that as nutritional resources become less available in the region during winter that the deer travel considerable distance to TLC to take advantage of the habitat available there. The browse created by annual timber harvest and food plots becomes very attractive in winter. The basic thought on why prevalence rates are lower in recent years is because TLC has raised the nutritional plain through both natural habitat manipulation and food plotting practices. The deer are entering winter less nutritionally stressed and less Rut stressed due to improved buck doe ratios. Another factor is that the overall age structure of the herd has been reduced
significantly by aggressively targeting mature does and reducing the doe herd which also helps reduce the TB exposure risk.
4) The timber management, food plot tactics and focused harvest strategies on the right animals have all been part of this winning formula. One of the key goals of the herd management program is to bring the average doe age down while increasing the age of the available bucks. Younger does have healthier fawns and more buck fawns. Older does tend to be less healthy and often their fawns are not carried to term due to the stress of winter. Interestingly enough, older stressed does often have 2 buck fawns but it doesn’t do anyone any good if they don’t carry them to term or if they are not recruited. (Recruited being defined as being part of the herd 1 year after being born. Turtle Lake Club has a recruitment rate today of about 86% - even with an estimated 80 bears on the club). Dr. Kroll suggested that the reason that stressed does tend to have more buck fawns is a result of Mother Nature and a built in mechanism for population control.
5) Doe fawns can actually be bred at 6 months of age if they reach roughly 80 lbs. This is a great indicator of herd health and roughly 30% of all does on Turtle Lake are being bred at this early age today.
6) A key measurement used to determine how well the deer are doing during the winter health check is through measuring their fat reserves. This can be accomplished through weighing the kidney and then by weighing the fat surrounding it. The target is a 4 to1 fat to kidney ratio.
7) Fetuses are also measured and the breeding date is established through a tool partially developed by our own Joe Hamilton. Several of the does that I witnessed were bred between October 27 and 29th last year. Yes, the rut appears to have been early on Turtle Lake this past hunting season. The result of any well managed deer herd with appropriate buck to doe ratio will result in a shorter intense rut that results in a smaller window for fawns hitting the ground in the spring. This will increase their chance of success by avoiding predation and ensures fawns will have enough time to prepare for the upcoming winter. If fawning is spread out over several weeks, predators have a longer window to find new born fawns.
8) Doe age, weights, ovaries, lymph nodes, fetuses, kidneys, bone marrow, and livers were collected and inspected as well. Several forms of scientific data can be collected from these organs and tissues for evaluation. For example, ovary scarring will indicate how many times a doe entered estrus prior to being bred. As the buck to doe ratio improves more does will be bred at the first opportunity.
9) Another item that was collected directly from the harvested animals was deer droppings. Dr. Kroll suggested that his team can analyze the feces and determine how efficient their diet is. He also did clarify that you cannot use deer droppings to determine sex or size of specific animals, although their diet will be evident in their feces.
10) I also learned that Turtle Lake Club does not have a mandatory antler restriction program. They target for harvest bucks that are 4.5 years or older based upon body characteristics. By doing so they are ensuring that they are improving buck to doe ratios and that there are plenty of bucks in each age class.

One of our core building blocks and the one that I believe is the most difficult to accomplish is herd monitoring. The work that is being done on the Turtle Lake herd takes monitoring to a whole new level and I believe the dividends from this work will pay dividends for years to come. From what I understand Dr. Kroll will begin to publish information related to his years of study at the Turtle Lake Club sometime in the near future. We can only hope that this happens soon and his body of work becomes the core foundation for our state adopted management strategy for the overall herd health of our beloved whitetail throughout the state of Michigan.

[kenn1320]

"He also did clarify that you cannot use deer droppings to determine sex or size of specific animals, although their diet will be evident in their feces."

Thanks for sharing this info. Interesting the guy writing this also attended Tony Laprats boot camp. Seems Tony and the Dr disagree on another topic, deer droppings.

[DEERSLAYER]

I also disagree with Dr. Kroll on deer droppings.

[kenn1320]

I sent a text to a guy who his dad had a deer facility some years ago. I asked him about the clumps versus the pellets. He said he had heard the same thing, but that consistency is determined by diet, not gender. I took it one step further and explained my findings of clumps only around what I would call a buck bed, and when I find multiple beds near farm fields, they always contain pellets. I asked, could it be that the bucks have a different diet then does at different times of the year? He said its possible. Maybe this is why I see a difference in the droppings? I have one more guy to contact and he will have the final word in my opinion. He owns an 80 acre enclosure for deer hunting(Im not a fan of it, but what he does with his land is up to him). The DNR made sure there were no deer left on that land when he fenced it off. He only has bucks in that area now, and in his breeder pen has 1 buck and lots of does and young bucks. The young bucks are moved out to the big pen prior to breeding season. Ill have to ask him what kind of droppings are in the buck only pen, that should tell the story!

[DEERSLAYER]

I don't agree with the clumping, but if I find 1.25" pellets I have no doubt it didn't come from a fawn or yearling. More likely at least a 4.5 year old buck.

[kenn1320]

if I find 1.25" pellets

DS, I have never seen a pellet that big. Would you happen to have any pictures? If you find a pellet that big, your saying a doe of the same age (4.5+) doesnt have similar pellet size? Do you find the clumping ever in close proximity of buck beds like I do? Could it be diet based and time of year, meaning are you finding pellets right now, or clumps now, pellets later? I posted a pic of a large clump in the thread "classic buck bed". This is great discussion, would be great to hear from some other members...

[DEERSLAYER]

Unfortunately I don't have any pictures. That was back when I had a 35mm camera so I wasn't going to waste expensive film on turds. I have not seen pellets that big in a long time. I don't pay THAT much attention to clumping since I have seen some does do this, but I do pay attention somewhat. I suppose a 4.5 year old doe could have big pellets like that, but I don't think you are likely to find any does big enough to make them big. At least not where I hunt. My biggest doe was about 170lbs.+ and there were no pellets near that big around the fallen hemlock she had been feeding on that week. I think clumping has more to do with diet. On the other hand I do think that very large bodied deer may clump more often than other deer due to their larger intestine size, but this is just a guess. This is a subject that I think I am going to start paying more attention to.

Dan, if your reading this, do you remember if you seen much "clumping" from that 300lb slob?

[dan]

Dan, if your reading this, do you remember if you seen much "clumping" from that 300lb slob?

I don't recall... However, I have never noticed a consistant "poop" pattern that was reliable.
The only way to know for sure for me if there is such a varible ( which I personally doubt ) is to go to a fenced deer farm and compare between the buck and doe pens / mature and sub-mature pens.
I personally think there is a difference in size, but not consistantly, meaning that a young deer may occasionally have large pellets or poop clumps, and a old deer may occasionally have small..