Natural mortality rates

[Dumbluck]

I'm sure someone on here has seen a study on the natural mortality rate of bucks. If you have a link can you please post it or if you'd like to discuss it let's hear it. I would expect each property to be different. I have one small farm we hunt that it seems very hard to get them to live above 3.5. We can pass them up and just watch them but we lose a lot of 3 year olds on that farm after the season is over. I found every possible shooter deer going into this season dead shed hunting. There may have been some foul play but there is no way to tell; I honestly think they died from infections late winter. The 3 year olds seem to be the hardest on their bodies during the rut so it makes sense in my head that they would have a higher mortality rate.

 

[BSK]

Problem is, radio/GPS collar studies with mortality sensors find VERY different numbers from place to place. Like you stated, I think buck natural mortality rates (death other than by hunters) is very site specific. My gut feeling is that mortality is VERY high for yearling bucks (they are stupid and feeling their first rut, getting themselves into all sorts of trouble), falls dramatically for 2-4 year-olds, then increases rapidly for 5+ year-olds. This is especially true in rugged hardwood terrain. Chasing does through the hills is very stressful, and high-quality food resources limited in those areas, producing extremely high post-rut mortality for bucks 5+ years old. Farm country is a different story.

 

[BigAl]

Any data on what CWD is doing to buck mortality rates, other than if they get it, they die?

 

[BSK]

Any data on what CWD is doing to buck mortality rates, other than if they get it, they die?

Haven't seen any good data on that, although I'm sure someone has done those studies.

 

[Dumbluck]

Problem is, radio/GPS collar studies with mortality sensors find VERY different numbers from place to place.

That's what I have experienced on different Farms as well. Farmland deer with good habitat seem to survive better than woodland properties. I have one woodland farm that I would speculate that the survival rate past 3 years old is only around 10% without hunter intervention. I seem to lose a tremendous amount of 3 year olds after the season. I think it has a lot to do with the 3 year old bucks in that area rut extremely hard and fight each other creating injuries that turn into infections. I have killed a bunch of bucks over the years on that farm with swollen foreheads and puss coming out from fighting.

 

[BSK]

That's what I have experienced on different Farms as well. Farmland deer with good habitat seem to survive better than woodland properties.

I've seen bucks make it to 8 1/2 in farm country. I've never seen a buck make it past 6 1/2 in ridge-and-hollow hardwoods.

 

[BSK]

I seem to lose a tremendous amount of 3 year olds after the season. I think it has a lot to do with the 3 year old bucks in that area rut extremely hard and fight each other creating injuries that turn into infections. I have killed a bunch of bucks over the years on that farm with swollen foreheads and puss coming out from fighting.

Worked on a 1,000-acre high-fence in TN. Bucks had to be 4 1/2 before they could be shot. This lead to a lot of bucks making it to maturity. Terrain and habitat were rolling hills, about 60% hardwoods, and the rest pasture, agriculture, and tall grasses. Yet they could hardly ever get a buck past 6 1/2. Why? The high number of mature bucks in an enclosed environment lead to a blood-bath of fighting. Every year, post-season, we would have to go around and find all the mature bucks that had been killed by other bucks. It was a shockingly high number.

 

[BigAl]

Worked on a 1,000-acre high-fence in TN. Bucks had to be 4 1/2 before they could be shot. This lead to a lot of bucks making it to maturity. Terrain and habitat were rolling hills, about 60% hardwoods, and the rest pasture, agriculture, and tall grasses. Yet they could hardly ever get a buck past 6 1/2. Why? The high number of mature bucks in an enclosed environment lead to a blood-bath of fighting. Every year, post-season, we would have to go around and find all the mature bucks that had been killed by other bucks. It was a shockingly high number.

I've heard the same. I know someone that hunted a high fence ranch. They had the buck to doe ratio at 1:1 and they said it was common to find bucks dead due to the fighting. So they took the ratio up to something like 1.2 or 1.4 to 1, and it helped their mortality rate. Not sure if that duplicates over to free range deer in most places, but in heavily managed areas I bet it happens.

 

[Dumbluck]

I've seen bucks make it to 8 1/2 in farm country. I've never seen a buck make it past 6 1/2 in ridge-and-hollow hardwoods.

I saw some tremendously old deer on an agricultural place I had, and it seemed much easier to get them to survive past 3. Those deer were homebodies for the most part, which made it excellent for trophy management. They would mill around in extremely thick cover during the day and venture out mostly at night. I would suspect that is why they had a good survival rate against the hunters around there.
The woodland properties the deer seem to travel farther exposing themselves to more hunters making it harder to get them to 3 and our target age of 4+, but even when we do get them past the season as a 3 year old I find a bunch of them dead shed hunting. We also seem to get EHD much worse on these properties, I'm assuming because the deer are drinking out of ponds, puddles, ect... where the ag deer had a running river and springs.

There are many variables but I find it fascinating how habitat directly seems to affect the mortality rates.

I also think about Texas, many places down there don't even shoot deer until they are 8 years old. Most of our deer here would have gone downhill for 2-3 years in many cases if they survived that long.

I've only seen 1 woodland deer live to 8 years old and he remained about the same size since he was about 5, and started getting just a hair smaller after 6. There have been very few deer I've watched over the years make it to 6 as a buck.

 

[BSK]

I saw some tremendously old deer on an agricultural place I had, and it seemed much easier to get them to survive past 3. Those deer were homebodies for the most part, which made it excellent for trophy management. They would mill around in extremely thick cover during the day and venture out mostly at night. I would suspect that is why they had a good survival rate against the hunters around there.
The woodland properties the deer seem to travel farther exposing themselves to more hunters making it harder to get them to 3 and our target age of 4+, but even when we do get them past the season as a 3 year old I find a bunch of them dead shed hunting. We also seem to get EHD much worse on these properties, I'm assuming because the deer are drinking out of ponds, puddles, ect... where the ag deer had a running river and springs.

There are many variables but I find it fascinating how habitat directly seems to affect the mortality rates.

I also think about Texas, many places down there don't even shoot deer until they are 8 years old. Most of our deer here would have gone downhill for 2-3 years in many cases if they survived that long.

I've only seen 1 woodland deer live to 8 years old and he remained about the same size since he was about 5, and started getting just a hair smaller after 6. There have been very few deer I've watched over the years make it to 6 as a buck.

I'm only talking natural mortality, not mortality associated with hunting. Even without hunting, you wouldn't see many bucks older than 6 in ridge-and-hollow hardwoods. They simply don't survive the rigors of the rut.

 

[Dumbluck]

I'm only talking natural mortality, not mortality associated with hunting. Even without hunting, you wouldn't see many bucks older than 6 in ridge-and-hollow hardwoods. They simply don't survive the rigors of the rut.

Yes I completely agree with that. I wish hunters would realize just how few deer actually survive to 4+ without hunter intervention. There seems to be an overwhelming belief that if the deer don't get shot they will survive or many of them will survive and that's just not the case on many farms.

 

[BSK]

Yes I completely agree with that. I wish hunters would realize just how few deer actually survive to 4+ without hunter intervention. There seems to be an overwhelming belief that if the deer don't get shot they will survive or many of them will survive and that's just not the case on many farms.

Exactly. It's that misconception you can "stockpile" older bucks. You really can't. Time and time again when I do a photo census of a new property (most in western Middle TN) I will find the buck age structure is very similar, and this is true even on very large properties with tightly controlled harvests of only mature bucks. You can produce more total bucks, which will give you a few more mature ones, but you can't produce a population with a high percentage of mature bucks.

 

[AlabamaSwamper]

They definitely seem to disappear from something other than hunting the older they get

 

[Dumbluck]

You can produce more total bucks, which will give you a few more mature ones, but you can't produce a population with a high percentage of mature bucks.

Have you ever looked to see what the numbers might look like on these farms for survival past 3 years old?

I typically hear "we have X amount of young of bucks, if we pass them up we will have a bunch of mature deer in a year or two". I typically take their X number and multiply it by 10% and say no you I may have this many mature deer to hunt. So if it's 30 they may have 3+/-. The 10% may be high or it may be low but what I'm trying to persuade them to see is that many of them just die without hunter intervention.

I have a guy I talk to every year that says he wants to do trophy management but in the same sentence will say "we have 35 young bucks using the farm we can shoot a few of them". Then calls and ask where all the mature deer are every year. I tell him if he really wants to do trophy management he can shoot ZERO deer under 3 or he will never have any actual mature deer consistently, he might have one or two here and there but they don't all live that long to begin with.

 

[Lost Lake]

Exactly. It's that misconception you can "stockpile" older bucks. You really can't. Time and time again when I do a photo census of a new property (most in western Middle TN) I will find the buck age structure is very similar, and this is true even on very large properties with tightly controlled harvests of only mature bucks. You can produce more total bucks, which will give you a few more mature ones, but you can't produce a population with a high percentage of mature bucks.

I agree 100%. I wish more understood this.

 

[LenS]

BSK, or any others, just out of curiosity what is it that would be the "official" cause of death for a western-middle TN buck after a particularly stressful mating season? I understand that the stress of the rut is what runs them down, but is it infection, malnutrition, pneumonia, or some other condition that actually kills them?

 

[BSK]

BSK, or any others, just out of curiosity what is it that would be the "official" cause of death for a western-middle TN buck after a particularly stressful mating season? I understand that the stress of the rut is what runs them down, but is it infection, malnutrition, pneumonia, or some other condition that actually kills them?

Stress and injury-induced illnesses. In essence, they are so worn down physically from the rut, or have suffered such severe injuries during the rut, they physically can't make it through the winter. They simply succumb to over-all poor condition late in the winter.

It is commonplace for mature bucks to lose 30% of their body weight during the 6 weeks of the rut. Imagine you weigh 200 lbs and in 6 weeks you run yourself ragged until you only weigh 140 lbs. What level of health would you be in? Perhaps not even survivable condition.

 

[BSK]

Have you ever looked to see what the numbers might look like on these farms for survival past 3 years old?

I typically hear "we have X amount of young of bucks, if we pass them up we will have a bunch of mature deer in a year or two". I typically take their X number and multiply it by 10% and say no you I may have this many mature deer to hunt. So if it's 30 they may have 3+/-. The 10% may be high or it may be low but what I'm trying to persuade them to see is that many of them just die without hunter intervention.

I have a guy I talk to every year that says he wants to do trophy management but in the same sentence will say "we have 35 young bucks using the farm we can shoot a few of them". Then calls and ask where all the mature deer are every year. I tell him if he really wants to do trophy management he can shoot ZERO deer under 3 or he will never have any actual mature deer consistently, he might have one or two here and there but they don't all live that long to begin with.

When looking at wild deer populations in western Middle TN, the age structures keep coming out right around 50% yearlings, 25% 2 1/2s, 15% 3 1/2s and 10% 4 1/2+. Now on very large properties where bucks are not open to harvest until 4 1/2, I will see a smaller percentage of the total adult male population being yearlings. Say around 40%. That is because hunting mortality of the bucks under 4 1/2 is much lower, hence 2 1/2 and 3 1/2 year-old bucks make up a higher percentage of the pre-hunt population. But it's not a massive amount higher. Again, perhaps 10% more 2 1/2s and 3 1/2s in the pre-hunt population than on smaller properties that are more affected by surrounding hunting pressure.

 

[Dumbluck]

This is excellent information. I always appreciate the feedback.

I kind of have a question like LenS. I have heard that bucks with head injuries i.e. puncture wounds that get infected have a high mortality rate because the infection gets into their brain. I have no idea if that has merit or not.

 

[BSK]

Actually, one of the highest mortality rates for bucks is from broken skulls due to rubbing, sparring and fighting. Placing so much pressure on their antlers often cracks the skull plate near the antler pedicle. Bacteria then gets into this crack causing a brain abscess to form. These are quite common and quite lethal.

 

[LenS]

I killed a 9 point that I had photos of. I was shocked at how much weight he had lost in just a couple of weeks. He also had 4 different puncture marks from fighting that I had noticed. The last 6 weeks had definitely been tough on him!

 

[casjoker]

I don't study deer enough in East TN and the size difference between TN deer and the ones I hunt in Maine and Indiana makes it hard for me to judge the ages on the hoof. I know myself and hunting buddies have shot deer in Maine (big woods northern Maine) and farmland central Indiana that was (3 total) 6.5 2 in Maine, (2 total) 7.5 one in Maine, and one 13.5 Maine. The biologist said we did him a favor there was no way he would have made it through the winter, hardly had any teeth left. All the Maine deer weighed over 210lbs with two in the 220 range field dressed. The deer in IN dressed between 180-205 LBS.

The rest, twenty plus were 4.5 and under. All deer 6 points or bigger in ME and IN were aged by state biologists. I have only had two aged in TN. One was a huge body 6 pointer (167lbs) I shot in Knoxville and a nice 8 killed in the same area. 6pt was 5.5 and the 8 was 4.5, On the 8 I don't have the weight recorded for some reason. They were taken in an area that hadn't been hunted for 3-4 years and was 2 of 5 big-bodied/racked deer I had on trail cams. The area in Knoxville was opened up to three other hunters the following year. I have never seen anything bigger than small basket 6's since and stopped hunting the property about 3 years ago.

I bet some of those mountain deer are living well past 4.5 years and have hardly seen much for people or hunting pressure, same with big woods Maine. The farm belt in Indiana is just easy living and grows them plenty and quickly.

Not sure if any of the above is super relevant but I like this topic.

 

[megalomaniac]

Not scientific at all... just years of observations.

Virtually all 2.5yos make it to 3.5 if they aren't shot. 3/5 3.5yos make it to 4.5. 2/5 4.5yos show back up at 5.5. 1/5 5.5yos show back up at 6.5.

Not scientific, but it's a pretty decent sample size for middle TN

 

[Hillbilly Hunter]

This is a fascinating read. We are definitely finding needles in a haystack when we do kill one 4.5 or older.

 

[Andy S.]

They definitely seem to disappear from something other than hunting the older they get

Amen!

 

[Andy S.]

..................2/5 4.5yos show back up at 5.5. 1/5 5.5yos show back up at 6.5.

Anecdotally, I seen this phenomena for years at Ames. Due to this, I tell hunters to truly give that 4.5 buck some thought if he/she REALLY wants to shoot him, especially if they are hunting smaller acreage farms. In the mostly hardwoods environment I typically hunt in SW TN, there is a good chance a hunter will never see him again after 4.5, even if he lives to be 6.5 on the landscape. I'm not advocating shooting all 4.5s, just that they truly do seem to disappear after that magical 4.5 year old season. Not all, but most are never seen again by me, my buds, or our trail cameras.

 

[jaybird62]

After watching deer on my farm since 2013 I have learned that any buck with the characteristics of a 3 1/2-year-old that's not a "resident" (showed up on camera previous couple of months) will never be seen twice. I find a couple of 2 1/2- to 3 1/2-year-old familiar deadhead bucks the past three years that lived through the season but died before I start shed hunting in early March. Food quality is high and available, so mortality is something else. Four out of five deadheads found are bucks:does over the past eight years. I have noticed that I don't find yearling buck deadheads like I did the first couple of years.

 

[JN]

This has been a great read and very informative. I have always wondered what happened to a few bucks that I know made it through the season but then just disappeared.

 

[Cheshire]

I'm sure someone on here has seen a study on the natural mortality rate of bucks. If you have a link can you please post it or if you'd like to discuss it let's hear it. I would expect each property to be different. I have one small farm we hunt that it seems very hard to get them to live above 3.5. We can pass them up and just watch them but we lose a lot of 3 year olds on that farm after the season is over. I found every possible shooter deer going into this season dead shed hunting. There may have been some foul play but there is no way to tell; I honestly think they died from infections late winter. The 3 year olds seem to be the hardest on their bodies during the rut so it makes sense in my head that they would have a higher mortality rate.

Very interesting thread

 

[wobblegobble]

I've seen bucks make it to 8 1/2 in farm country. I've never seen a buck make it past 6 1/2 in ridge-and-hollow hardwoods.

I had a 7.5 year this year in the mountains and killed a 6.5 last season in the same location...I found a dead 7 year old two years ago...I will have at least three 6 year olds this year.