B
bat man
Guest
Our DNR is tasked with many functions, and from a hunting standpoint whitetail deer are the number one priority. Deer hunters and viewers spend billions of dollars annually, and the same animal causes millions in damage to crops and vehicles. Finding the sweet spot that keeps everybody happy is an impossible task, but working towards a reasonable compromise when it come to deer numbers, and then successfully managing for that level is what management of the deer herd is all about.
There are many ways to manage a deer herd, and our DNR’s primary tool is a model. The model is used both to estimate the herd size, and for setting harvest allocations. The model in its simplest terms receives data inputs, and spits out information our DNR uses to make decisions in managing our deer herd. An audit of this model and how our DNR uses it is needed. The model is not functioning in the real world as it should on paper, and DNR recalibration is not at a level that allows the model to function.
When the deer harvest of 2014 is tallied, it may be the lowest recorded harvest since 1982. Our DNR will issue press releases stating the record low harvest was due to a conservative harvest approach in response to hunter demands to rebuild the herd, and kudos to them for finally taking action, but how did the herd slide so far? How did a deer harvest that was closing in on 300,000 animals in 2004 shrink so far that we will harvest less than 150,000 deer 10 years later. Could we really see the lowest harvest in 33 years? Either the model or how we use it have failed us.
The MN DNR led 2005 – 2007 stakeholder goal setting proceedings suggested a statewide herd reduction of 11%. Revisions to those stakeholder meetings would later change that figure to a 9% reduction from 2005 levels, but the herd has been slashed much, much further. The DNR model will suggest the state is now at that goal, but the model stands alone in that belief. From 2004 through 2013, deer vehicle collisions are down 51% as reported by the MN Department of Public Safety. The deer harvest is down 41%. Pope and Young record book entries by our Chatfield MN based conservation group are off 49% with consistent membership. Area meat processors report deer tallies 40% lower than DNR suggested reports, and hunter satisfaction with deer seen on stand has dropped 40+% in central MN.
How can the model show the herd is only down 9% when every other data set suggests the MN deer herd has been slashed well past 40%? Recalibration is part of the answer. Our DNR model allows them to go back in time and change deer densities to match what the model suggests. Here is an example.
In 2006, zone 225 in East Central MN was one of the zones to go through the stakeholder goal setting process. The DNR data at the time said there were 24 deer per square mile in zone 225. The stakeholders agreed to a 25% reduction (new goal range of 16 – 20 dpsm). As time goes by, the DNR has the ability to change that ‘24 deer per square mile’ to 20 dpsm, or 17, or 15 dpsm. But changing the original estimate does not change the reduction percentage, and the herd numbers keep going lower and lower. Going back in time and lowering the original estimated number of deer is a big reason the DNR can show deer numbers down only 9% or 11%, when every other set of data shows 40+% reductions. This practice of altering the original estimates may be necessary at times, but when hard science exists that says your model is wrong, you can’t ignore it. It happens more than you think.
In 2007 the stakeholders voted to stabilize the deer herd size in zone 240. At the Brainerd listening session last winter a gentlemen wanted to how zone 240 had an estimated 42 dpsm in the mid 2000’s and was to remain at that level, but now had less than half the deer and was at goal? It is the magic eraser and its ability to go back in time to change estimated deer numbers. The DNR model will suggest the herd size has been the same from 2006 through 2013, but the number is now 19 instead of 42 deer per square mile. The deer harvest is down 42% in zone 240 during that time period. The herd size has been anything but stabile.
Back to zone 225.
In 2006 the DNR performed a ground survey of zone 225, which was now under intensive harvest regulations (5 antlerless deer per hunter, sometimes 7 with the early antlerless rifle season). Their counts calculated 7 deer per square mile. The DNR thought there must be a mistake, so they flew the zone in 2007 and using the self described $15,000 ‘gold standard’ population estimate tool, and they counted 8 deer per square mile. Then they threw the 2 counts that are designed to double check the models accuracy into the garbage and walked away from zone 225. Attempts to reveal the findings of another aerial survey in 2010 produced a $267 invoice for the data to be delivered, which we declined. The DNR spent the time and money for 2 scientific tools to verify the models accuracy, and when the data did not match the model, they ignored the real numbers and continued over estimating the herd, and selling excessive antlerless tags in a unit proven to be well below the stated goal.
The model cannot function optimally when you don’t apply the double checks that are in place to insure model accuracy. The farmland model is said to function best when the areas of the state that are conducive are ‘surveyed’, or have the deer counted in a timely manner. In the transition zones of the state where the forest meets the prairie, aerial recalibration is the primary tool the DNR uses. When winter conditions are right, helicopters fly a predetermined stratified grid of a deer zone and count the deer. The number of deer that are counted are put into a formula that estimates the herd size of the unit. This ‘gold standard’ approach is expensive ($15,000 per unit flown), but the MN DNR states there is no better way to estimate the herd size. Failure to recalibrate by aerially counting the deer once every 5 years lessens the accuracy of the model. From 2004 through 2013 we only flew and counted 42 different units. That puts us on pace to fly the units once every 12 – 15 years when the models accuracy falls off quickly after 4 - 5 years. Failure to count the deer lessens the models potential, but by how much we don’t know.
Our model or its use and interpretation by the DNR is failing as a tool for managing the deer herd. Last December, with the deer harvest almost 98% calculated, some concerned members of the Morrison County MDHA chapter scheduled a visit with Beau Liddel, the Area Manager of the DNR Little Falls office. The MDHA members had concerns with the low deer numbers, and the continued use of intensive harvest in the zone. They were informed that for 2014, zones 221, and 222 would again be intensive harvest, with a probable early antlerless rifle season, and possibly a first ever earn a buck restriction. Had these concerned hunters not combined with several others groups to make some noise, the zones would have experienced a further reduction of the herd. Now the regulations are out and each zone is allowed only one deer per hunter. The DNR's own model was ignored after social pressures grew strong enough to ignore it. Our own DNR does not even fully trust the model. Our DNR’s model and deer management strategies need an over haul. We need more herd monitoring tools. We need accountability. We really need an audit to help our DNR figure out what tools are available to help better monitor and manage our deer herd.
Thank you for your consideration,
Brooks Johnson
MDDI (MN Deer Density Initiative)
There are many ways to manage a deer herd, and our DNR’s primary tool is a model. The model is used both to estimate the herd size, and for setting harvest allocations. The model in its simplest terms receives data inputs, and spits out information our DNR uses to make decisions in managing our deer herd. An audit of this model and how our DNR uses it is needed. The model is not functioning in the real world as it should on paper, and DNR recalibration is not at a level that allows the model to function.
When the deer harvest of 2014 is tallied, it may be the lowest recorded harvest since 1982. Our DNR will issue press releases stating the record low harvest was due to a conservative harvest approach in response to hunter demands to rebuild the herd, and kudos to them for finally taking action, but how did the herd slide so far? How did a deer harvest that was closing in on 300,000 animals in 2004 shrink so far that we will harvest less than 150,000 deer 10 years later. Could we really see the lowest harvest in 33 years? Either the model or how we use it have failed us.
The MN DNR led 2005 – 2007 stakeholder goal setting proceedings suggested a statewide herd reduction of 11%. Revisions to those stakeholder meetings would later change that figure to a 9% reduction from 2005 levels, but the herd has been slashed much, much further. The DNR model will suggest the state is now at that goal, but the model stands alone in that belief. From 2004 through 2013, deer vehicle collisions are down 51% as reported by the MN Department of Public Safety. The deer harvest is down 41%. Pope and Young record book entries by our Chatfield MN based conservation group are off 49% with consistent membership. Area meat processors report deer tallies 40% lower than DNR suggested reports, and hunter satisfaction with deer seen on stand has dropped 40+% in central MN.
How can the model show the herd is only down 9% when every other data set suggests the MN deer herd has been slashed well past 40%? Recalibration is part of the answer. Our DNR model allows them to go back in time and change deer densities to match what the model suggests. Here is an example.
In 2006, zone 225 in East Central MN was one of the zones to go through the stakeholder goal setting process. The DNR data at the time said there were 24 deer per square mile in zone 225. The stakeholders agreed to a 25% reduction (new goal range of 16 – 20 dpsm). As time goes by, the DNR has the ability to change that ‘24 deer per square mile’ to 20 dpsm, or 17, or 15 dpsm. But changing the original estimate does not change the reduction percentage, and the herd numbers keep going lower and lower. Going back in time and lowering the original estimated number of deer is a big reason the DNR can show deer numbers down only 9% or 11%, when every other set of data shows 40+% reductions. This practice of altering the original estimates may be necessary at times, but when hard science exists that says your model is wrong, you can’t ignore it. It happens more than you think.
In 2007 the stakeholders voted to stabilize the deer herd size in zone 240. At the Brainerd listening session last winter a gentlemen wanted to how zone 240 had an estimated 42 dpsm in the mid 2000’s and was to remain at that level, but now had less than half the deer and was at goal? It is the magic eraser and its ability to go back in time to change estimated deer numbers. The DNR model will suggest the herd size has been the same from 2006 through 2013, but the number is now 19 instead of 42 deer per square mile. The deer harvest is down 42% in zone 240 during that time period. The herd size has been anything but stabile.
Back to zone 225.
In 2006 the DNR performed a ground survey of zone 225, which was now under intensive harvest regulations (5 antlerless deer per hunter, sometimes 7 with the early antlerless rifle season). Their counts calculated 7 deer per square mile. The DNR thought there must be a mistake, so they flew the zone in 2007 and using the self described $15,000 ‘gold standard’ population estimate tool, and they counted 8 deer per square mile. Then they threw the 2 counts that are designed to double check the models accuracy into the garbage and walked away from zone 225. Attempts to reveal the findings of another aerial survey in 2010 produced a $267 invoice for the data to be delivered, which we declined. The DNR spent the time and money for 2 scientific tools to verify the models accuracy, and when the data did not match the model, they ignored the real numbers and continued over estimating the herd, and selling excessive antlerless tags in a unit proven to be well below the stated goal.
The model cannot function optimally when you don’t apply the double checks that are in place to insure model accuracy. The farmland model is said to function best when the areas of the state that are conducive are ‘surveyed’, or have the deer counted in a timely manner. In the transition zones of the state where the forest meets the prairie, aerial recalibration is the primary tool the DNR uses. When winter conditions are right, helicopters fly a predetermined stratified grid of a deer zone and count the deer. The number of deer that are counted are put into a formula that estimates the herd size of the unit. This ‘gold standard’ approach is expensive ($15,000 per unit flown), but the MN DNR states there is no better way to estimate the herd size. Failure to recalibrate by aerially counting the deer once every 5 years lessens the accuracy of the model. From 2004 through 2013 we only flew and counted 42 different units. That puts us on pace to fly the units once every 12 – 15 years when the models accuracy falls off quickly after 4 - 5 years. Failure to count the deer lessens the models potential, but by how much we don’t know.
Our model or its use and interpretation by the DNR is failing as a tool for managing the deer herd. Last December, with the deer harvest almost 98% calculated, some concerned members of the Morrison County MDHA chapter scheduled a visit with Beau Liddel, the Area Manager of the DNR Little Falls office. The MDHA members had concerns with the low deer numbers, and the continued use of intensive harvest in the zone. They were informed that for 2014, zones 221, and 222 would again be intensive harvest, with a probable early antlerless rifle season, and possibly a first ever earn a buck restriction. Had these concerned hunters not combined with several others groups to make some noise, the zones would have experienced a further reduction of the herd. Now the regulations are out and each zone is allowed only one deer per hunter. The DNR's own model was ignored after social pressures grew strong enough to ignore it. Our own DNR does not even fully trust the model. Our DNR’s model and deer management strategies need an over haul. We need more herd monitoring tools. We need accountability. We really need an audit to help our DNR figure out what tools are available to help better monitor and manage our deer herd.
Thank you for your consideration,
Brooks Johnson
MDDI (MN Deer Density Initiative)
