Buck harvest as herd indicator

Wisc correct me if I am wrong. When they did the audit on SAK there were several things that would throw the SAK system off. The number 1 thing was Earn-a-buck. I believe they said also that for SAK to be accurate that they had to do some visual census as to fawn count in August or September which in my opinion wasn't done and to this day is not done. The problem with that is that the Wisconsin DNR has already set the Antlerless quota by this time. The SAK system may be the best system for estimating deer but if all the procedures of SAK are not followed it can be a total failure as is evident by it's complete failure in the Northwoods of Wisconsin.
 
I just cant understand how buck harvest can be so reliable for population indication. Escpecially when you have doe harvest goals swinging back and forth so violently.

Buck tag allocation is constant. Its one per hunter every single year and has been for many years.
Antlerless tags on the other hand have gone from a wild swing of 5+ anterless tags per person to areas where there are zero doe tags.

So if you have 25 hunters in a sq mile, he max bucks that can be taken is 25.
However, depending on the year and the populations of deer, you could feasibly have 125 antlerless tags available or 0 anterless tags available.
That hurts to read that actually.... 125 tags available in a sq mile... Never thought about that before....

Anyway, how do you extrapolate a population indicator out of that by relying mainly on the number of bucks that are taken?
The +/- variable in the estimation is out of this world.
 
I just cant understand how buck harvest can be so reliable for population indication. Escpecially when you have doe harvest goals swinging back and forth so violently.

Buck tag allocation is constant. Its one per hunter every single year and has been for many years.
Antlerless tags on the other hand have gone from a wild swing of 5+ anterless tags per person to areas where there are zero doe tags.

So if you have 25 hunters in a sq mile, he max bucks that can be taken is 25.
However, depending on the year and the populations of deer, you could feasibly have 125 antlerless tags available or 0 anterless tags available.
That hurts to read that actually.... 125 tags available in a sq mile... Never thought about that before....

Anyway, how do you extrapolate a population indicator out of that by relying mainly on the number of bucks that are taken?
The +/- variable in the estimation is out of this world.

SAK stands for sex, age and kill. In simple terms they figure the amount of fawns that are born are equal in doe and buck. So they take the number of bucks that are killed at each age group and then figure there are that many does born for that age class. They also have a base factor of the doe to buck ratio that factors into it along with several other factors, fawn survival, winter severity index and others. So the more bucks that are shot = more doe and buck fawns that were born the year before. This may have over simplified the system as there are a bunch of more factors that they use. I hope that makes sense.
 
Thanks Tom
 
It doesn't look like buck harvest is really used in the area I am in. As recently as 2010 permit area 156 had 2,000 bucks killed and the buck harvest dropped 33% from 2010 to 2013 but model says the population only dropped 7%.

In 2014 the model says that we are down 29% from 2010 but the buck harvest is down 50%. When I asked multiple biologists they say that the drop the model shows from 2013 to 2014 is due to the WSI average of 189 for the whole permit area. So the drop in buck harvest wasn't really considered??

Another thing I see when I look at numbers is that in 2011 after 2 years of managed the buck harvest dropped when it was intensive harvest. It appears that IH shifted the kill to antlerless. Switching from years of managed and intensive (2004-2013) to lottery (2014) would likely put much more pressure on the bucks as well. Based on my simple way of thinking, the actual population would be down more in 2014 than the lower buck harvest would indicate due to fewer antlerless permits.

Advisory team info screenshot for 156:
PA 156.JPG
 
According to DNR stats, buck numbers are going up. Zone 227, 2013- 2.3-3.0, 2012 1.6-2.5, 2011 1.7-2.4. But with the dnr numbers, what can you really believe? Without the number of hunters each year their numbers mean nothing. 40 years ago we had a square mile to our self. Now there are 21 hunters in that square mile.
 
Merchant alluded we should include # of hunters. But you still are in line for a % bump of x. That should cheer you up. The result of the process will be a % of X. Your deer numbers will be changing a % of X.
 
Advisory team info screenshot for 156:
View attachment 3975

You also need to look at your number of hunters, use 2006 on as the 2005 number has a discrepancy in almost every zone we represent that we need to figure out. Reported hunters and those in the deer report don't match.

You have 10% more hunters than 10 years ago w/o factoring in the number of guys bow and muzzle hunting. Your season may even have more days than 10 years ago?

Simplify it down and email all elected from the list stating the numbers in your packet are misrepresented. You can't show the buck harvest on a graph w/o factoring in more hunters and more days. More effort to yield less animals means the herd is down further than depicted in the data.
 
Jerry,
The numbers of firearms hunters is in the annual DNR harvest reports.
 
More effort to yield less animals means the herd is down further than depicted in the data.

ABSOLUTELY.
I have tried to make that statement over and over with notes sent to the DNR and elected.
upload_2015-2-14_10-54-33.png

upload_2015-2-14_10-54-56.png
 
You also need to look at your number of hunters, use 2006 on as the 2005 number has a discrepancy in almost every zone we represent that we need to figure out. Reported hunters and those in the deer report don't match.

You have 10% more hunters than 10 years ago w/o factoring in the number of guys bow and muzzle hunting. Your season may even have more days than 10 years ago?

Simplify it down and email all elected from the list stating the numbers in your packet are misrepresented. You can't show the buck harvest on a graph w/o factoring in more hunters and more days. More effort to yield less animals means the herd is down further than depicted in the data.

Yup I was thinking about that as well, but did not add it too my post.

2010 to 2013 we had 7% more hunters, the success rate dropped from 51% to 34%, and the buck harvest was down 33%. But the model says the population was down 7%. :eek:

I am curious what kind of statistics classes these biologists have taken. I have bachelors and masters degrees that required statistics and financial analysis. Not to hard to figure out when the description of what is going on does not match the actual numbers.

Brooks, I am preparing an email to Steve M. that I will CC you on, as well as Tom Hackbarth and some other legislators and the outdoors guys at the Strib and Pioneer Press. Might not have it ready until tomorrow morning.
 
Wisc correct me if I am wrong. When they did the audit on SAK there were several things that would throw the SAK system off. The number 1 thing was Earn-a-buck. I believe they said also that for SAK to be accurate that they had to do some visual census as to fawn count in August or September which in my opinion wasn't done and to this day is not done. The problem with that is that the Wisconsin DNR has already set the Antlerless quota by this time. The SAK system may be the best system for estimating deer but if all the procedures of SAK are not followed it can be a total failure as is evident by it's complete failure in the Northwoods of Wisconsin.
Tom, this is not the case. There are actually 2 doe/fawn surveys run each summer. One is done by the DNR/FWS while they are out on the road(this has been done annually since 1960) and the other is done by the public. I will post the link to Program page and the report below. If anyone is on the road a lot during August and September, I encourage them to participate in the Operation Deer Watch Program. There are links on the DNR website where you can download and print the tally sheets and report your observations. You are correct that EAB is a situation where the SAK gets skewed, the DNR freely admits that. Another thing that can skew the model is the harvest regulations that were used in the CWD Intensive Management Zone. In both of those situations the DNR did/does not use the SAK model. I don't believe that the SAK model failed in the Northwoods or anywhere else it is used. As I said in an earlier post, the model is fine when the numbers are stable and the DNR is trying to maintain the herd numbers, it is when the herd increases due to mild winters, etc., and the DNR tries to reduce the herd that they get into trouble. I think for years the DNR has misread(for lack of a better word) the model when it tells them the amount of tags they need to issue to reduce the herd to a given level, thus over-issuing tags on an unneeded scale. WI deer hunters are a very efficient bunch and there has never been a need to issue unlimited tags to the masses in most situations. WI hunters kill deer, and lots of them, IF they see them while in the field. When the population drops to the point hunters are not seeing deer it makes them pretty darn hard to kill. I can not remember where I heard this, but I was in a discussion on time and it got brought up that the DNR tends to issue "bonus tags" using a lower hunter success rate than what they use for the initial antlerless quota, if that makes sense. For example, if the DNR figures a 33% success rate for the regular unit quota, they only figure a 25% kill rate for the bonus tag allocation, thus causing them to issue even more tags than needed. Like I said, I can not remember where that conversation took place, but it may have been at the spring hearings a few years back.

Operation Deer Watch page: http://dnr.wi.gov/topic/wildlifehabitat/summerdeer.html

Survey results report pdf: http://dnr.wi.gov/topic/WildlifeHabitat/documents/reports/summerdeerob2.pdf
 
Wisc as I said in my 1st post Aug and September Surveys for does and fawns does absolutely no good when the antlerless quotas are set before that. A good example was in 2013 hunting season after a bad winter and low fawn production in Northwoods which local wildlife biologist and other local DNR people knew that the quotas should be lowered but it was decided by the higher ups that the quota was set and that it could not be lowered. Dr. Kroll also brought it up in his report that the DNR on local level needed to get out of office and boots on the ground, he found that the in-field observations were not getting done, which could have been from being under staffed. The deer watch by general public has only been going on for a couple of years and is to make the general public feel good as the Quotas have already been set by the time the results are tabulated. Also I think you may be wrong on saying that they didn't use SAK in earn-a-buck areas, at one point almost the whole state was in earn-a-buck and heard nothing that the SAK system was not being used. It was not until the 2006 audit that they were told that SAK was thrown off by earn-a buck. SAK may be good but only to the extent of how the DNR uses it. If it would have been used properly and adjusted when needed there would still be a decent number of deer in the Northwoods of Wisconsin.
 
FREEBORN

Can you make a statement that if hunter numbers have increased 25% at a steady pace over the past 10 years, and the buck harvest has declined 25% at a steady pace that the herd is down 50% or is that not accurate.

The reports the DNR have handed out claim since buck harvest is fairly steady, the herd is about the same size. The numbers above would not indicate that to me, but they don't talk hunter numbers (effort) in the packets
Unfortunately no, you are drawing a conclusion not calculating a result. You would need to have the appropriate data to calculate the impact caused by the increase in hunters. Keep in mind the confidence level in statistics increases with an increase in the data sampled (number of years or larger sample size) when calculating a result. For example, a trend is only a trend after 3 years until then it is a change and assigning correlation (cause and affect) cannot be attained with any level of confidence unless you have sufficient years in the sample.

You should be able to correlate the number of bucks harvested (decline) with the increase in hunters. To calculate the correlation you need to have a number of years (large sample size) to get any accuracy. 10 years or more if possible. If we have the numbers for a given zone send them to me and I will calculate the correlation for us to look at. I would need to know the # of bucks harvested by year, number of hunters by year. It would be interesting to see if there is a lag (cause then affect) with the increase in hunters. An increase in hunters this year may cause an increase in harvest this year but a decline 2-3 years from now.
 
BLB, in your charts is the # of hunters determined by the number of licenses sold or is it truly the number of hunters?

When I look at that data my conclusion is there are too many licenses being sold no matter the number of hunters? If year over year does are over harvested the impact of a yearly harvest is much greater as it impacts all future years harvest.

The DNR is claiming that harvests are down because there were less does permits (Licenses) sold this year. Their argument then is (affect/cause) less deer harvested because less licenses. If this is there hypothesis then how can they argue that more hunters would not cause more harvest (cause/affect) again.

It is common sense that more hunters hunting the same area should harvest more deer. That fact that you need to debate results that are self evident is like debating someone who will not recognize facts, almost impossible.

Seems like allot of obfuscation to me. The only way you are really going to get answers is if they would let you look at their calculations which will probably never happen.
 
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I am not sure if it has been mentioned, but shifting an area's regs from Managed to Lottery would throw off using buck harvest as a population guage. DNR has a survey that most Minnesotans want to shoot 1 deer. Give most Minnesotans 2 or more tags and most will still shoot 1 deer. They may want it to be a buck, but will be happy to shoot the first legal deer they see. So, if a we were to look at a single deer permit area's buck harvest over a 10 year span, and only use the years that it was Lottery, then that might be relevant data.
 
Tom, I believe the quotas are set when they are through necessity and general timing. What alternative would you propose? Doing the count earlier is not feasible. Sure, they could possibly wait a month or so longer to include those count numbers in the quota, but the archery season starts before the field survey is even over and bonus antlerless permits go on sale a month before that in mid-August, just as the field survey is getting started. The problem lies with the fact that field counts any earlier than what we do them now are extremely hard to do and therefore highly inaccurate. The woods are to thick and the fawns are to reclusive to get an accurate count, the fawn count would be highly suspect. Many does will not expose their fawns to roadsides and open fields where they can be easily counted until after they are a few months old. It would be next to impossible to get an accurate count in June and July with the heavy foliage. It is a very slippery slope no matter what one does. I totally understand what you are explaining about the 2013 season, and having the DNR adjust on the fly when numbers are shown to be lower than expected through in-field counts and surveys. But again, that is also not really a feasible alternative, the problem lies in that the field counts are most accurate in August and Sept but the seasons are about to start and all the permits have already been sold. It would be a huge undertaking for the state to have to refund all those permit fees and for the hunters to have to return all the extra, then non-valid permits. The only possible alternative I see to allow for the most up to date and accurate counts to have a direct impact on quotas for the year they are affecting would be to end the counts on Sept 15th to start compiling the data and then start the bow season a month later(around Oct 15th instead of Sept 15th) and not sell any bonus permits until after that time as well, so the numbers from the count could be complied and included in the quota setting process. All of that will be considered too late in the game by not only the DNR but the general public as well. Maybe I am not thinking far enough outside the box, but right or wrong, the timeframe is what it is and there isn't much that can be done about that situation that the hunters would not scream about. More flexibility by the DNR would be nice, but the feasibility of that walks a fine line? I don't think there is a good answer without hard choices by the DNR and hunters as well. The public Deer Watch program has been in affect in some form since 2009 and the mailed-in hunter surveys have been around far longer than that, since the mid-80's at least, all of which have been/are used to adjust the SAK model. EAB was first used in 1996 and was not used again until until 2002 and then only in CWD affected areas. It wasn't until 2004 that it was expanded into "other" areas of the state, so it does not surprise me at all that it was pointed out in 2006 that SAK didn't work with EAB rules, I would say they figured it out pretty quickly really. Figuring out it didn't work just 2 years after it was put into large scale use is not bad. As far as SAK not being used in EAB areas, the SAK data was compiled as it has been since the 60's, but it was not used to set quotas. Think about it, why would it have been, EAB zones need no data to set quotas, the quota is set by the number of bucks harvested and subsequently a doe for every buck kill. It was kill 'em all. For every buck registered, they already knew that a doe would be shot, no need to look any further than that. If historical data said 2,000 bucks were killed overall in that zone, they automatically assumed that 2,000+ does would also be killed. I agree that SAK is only good if used properly, and keep in mind the metrics they use to adjust it are constantly changing, similar to when EAB was put into affect, they had no idea how EAB would affect the overall model, and they adjusted when they did figure it out. The problem with EAB is it was grossly overused and I feel it was done purposely to meet the Forestry industry agenda of reducing the population. Again, I think the problem lies in the way they issue bonus antlerless permits when the model shows that a decrease in population is in order. Something must be done about the over-issuance of bonus antlerless permits when populations become high and warrant a decrease in the herd. I don't have a clue on an answer for that, but it is one area where the DNR has overstepped on many occasions.
 
Wisc earn-a buck doesnt screw up SAK in the year that it happens it screws it up in the years following. Also it was the outside Audit that told DNR that earn-a-buck messed up SAK or otherwise our DNR still would be using it the same as before earn-a-buck. There is a very simple method to do the survey before they set quotas, it is called Trail cameras. The Wisconsin DNR needs to get with technology. If they would raise license fee 1 dollar to be designated to buy Trail cameras they could buy $800,000 dollars worth of trailcamera equipment to verify that their SAK estimates are accurate.
 
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I am not sure if it has been mentioned, but shifting an area's regs from Managed to Lottery would throw off using buck harvest as a population guage. DNR has a survey that most Minnesotans want to shoot 1 deer. Give most Minnesotans 2 or more tags and most will still shoot 1 deer. They may want it to be a buck, but will be happy to shoot the first legal deer they see. So, if a we were to look at a single deer permit area's buck harvest over a 10 year span, and only use the years that it was Lottery, then that might be relevant data.
Some areas have moved from zone 4 to zone 2 in recent years and have also gone from shotgun to rifle. All harvest data would be hard to interpret with that change.

When did $5 youth tags come in place and what has that done to harvest numbers/ effort. I can not see how any definite conclusion could be made form kill data with changes in season structure.
 
I just cant understand how buck harvest can be so reliable for population indication. Escpecially when you have doe harvest goals swinging back and forth so violently.

Buck tag allocation is constant. Its one per hunter every single year and has been for many years.
Antlerless tags on the other hand have gone from a wild swing of 5+ anterless tags per person to areas where there are zero doe tags.

So if you have 25 hunters in a sq mile, he max bucks that can be taken is 25.
However, depending on the year and the populations of deer, you could feasibly have 125 antlerless tags available or 0 anterless tags available.
That hurts to read that actually.... 125 tags available in a sq mile... Never thought about that before....

Anyway, how do you extrapolate a population indicator out of that by relying mainly on the number of bucks that are taken?
The +/- variable in the estimation is out of this world.


Mark I presented a few figures at the Hinckley meeting.
Our fearless leader had proposed up to 38,000 doe permits plus additional landowner tags in an area with either 7700 (model estimate) or 4600 (aerial survey) adult deer in the fall population. That would come out to about 59 doe permits per section with an adult deer population of 7 (or 12) deer per square mile.

I will repeat that-Up to 59 doe permits per section in an area with 7 or 12 adult deer per section. I would bet this would excite guys that can not see why we are so disgusted with our DNR.

How can any seasons be set with such a large discrepancy in the estimates of deer numbers-7700 or 4600 adult deer in the fall population?????
 
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