Northeast Michigan Quality Deer Management Association 

Shifting to Quality Deer Management to Fight Deer Disease

 

Recent developments with the spread and establishment of chronic wasting disease (CWD) in central and western Michigan, along with a recent spike in bovine Tuberculosis (bTB) in the northeast are a big concern for Michigan hunters, farmers and conservationists. Our deer herd and hunting heritage are threatened. Hunters around the state are asking what can be done?

 

To prevent catastrophe, we will need to manage deer diseases actively and intelligently, using sound science where it can guide us, while also recognizing the importance of keeping hunters hunting.  The good news is that if we can achieve this balancing act, we will keep disease prevalence rates low and slow the spread of disease, while also enjoying high quality hunting experiences for many years to come

 

Keys to meeting the challenge of deer disease will be:

• Controlling spread of CWD through the movement of both live deer and deer carcasses. CWD has been spread great distances throughout the U.S. by humans. Deer farmers have moved infected live deer & elk and hunters have moved infected carcasses. We don’t have all the answers on the specifics, but with CWD now established in Michigan we are going to need both stronger measures to prevent additional infection from coming into Michigan from outside the state, and now also measures to limit risk of spread of disease within the state.

 

• Reducing disease spread through baiting, recreational feeding and livestock feeding. The science is clear, one of the most effective ways to spread TB and CWD is through bait piles and feed troughs where deer are exposed to high concentrations of infected saliva, urine, and feces and come into direct contact with other deer. According to DNR surveys, baiting is still popular with the majority of Michigan hunters, we have also heard from the DNR that they have had difficulty enforcing and getting successful prosecution of baiting violations. All stakeholder groups are going to need to work together to limit this risk with regulations that hunters will support, and law enforcement can enforce.

 

• Increasing and improving wildlife habitat is another key to better controlling  deer disease. When quality habitat is scarce, deer will congregate in high densities to obtain the food and cover they need to survive. These high densities expose deer to infection from other deer and their environment. In Michigan, winter is when thermal cover and food are most scarce, and we see large groupings of deer throughout the state. Another important period is the fawning season, during this time mature does become territorial, excluding all deer, even their own young, from their fawning territories.  If population is dense and neighboring habitat is also filled by other mature does, yearling does and bucks will be forced to disperse great distances, (“Population density influences dispersal in female white-tailed deer” by Lutz et al) potentially spreading disease. To control disease, we need to spread these animals out over more high quality winter and spring fawning habitat.

 

• Harvest more Does. Why harvest more Does? Quite simply in the CWD and TB areas, along with much of the rest of the lower peninsula, we have high deer densities, and those high densities result in to greater disease risk,  deer damage to wildlife habitat and farms, and greater human – deer conflict. Reducing doe numbers is the only proven way to reduce herd size. Research has shown that to reduce the size of a deer herd more than 30% of antlerless deer should be harvested every year. We aren’t coming close. According to the 2017 QDMA Whitetail Report, Michigan is harvesting does at a much lower rate per buck (.7) than virtually all of the top whitetail states. Examples include Wisconsin (1.0), Illinois (1.3), Iowa (1.2), Indiana (.9), Ohio (1.4). It should be clear that we can have high quality hunting, while harvesting more does to lower densities and disease prevalence. In addition, we know from DNR check station results that our does are much older than our bucks. At a late 2017 TB work group meeting Chad Stewart, Deer & Elk Biologist, DNR shared that 60 – 65% of the does checked in the core TB area were 3.5 or older. Research on CWD and TB tells us that the older a deer is, the more likely it is to be infected. Because mature bucks 3.5 and older in Michigan are relatively rare, the large numbers of much older does in our deer herd is our biggest disease risk. We need to look at our regulations, seasons and hunter education to increase doe harvest during the 2018 season. For example, regulations that protect yearling bucks cause hunting pressure to shift to Does, especially early in implementation. At the May NRC meeting Chad Stewart, DNR Deer, Elk & Moose specialist reported that in the Antler Point Restriction counties of Northwest Michigan, Doe harvest was up 13% while Doe harvest declined 16% in the surrounding non APR counties. We need to achieve similar, or better, results in our disease areas.

 

• Protect the majority of yearling bucks. Why protect the majority of yearling bucks? If you are a deer hunter, what animal dominates your dreams the night before a hunt? Which animals are you sharing pictures of from your game cameras? If you are not a deer hunter and want to better understand what motivates hunters, pick any deer hunting advertisement, in any hunting magazine, which deer is featured in that ad? Is it a young spike buck or a doe? Or is it a mature buck? Advertisers know what motivates hunters. Seeing more bucks and having the opportunity to harvest older bucks excites hunters, drives investments in hunting land, equipment, trips, habitat improvements, licenses, motivates them to sit in deer stands, and to work together to better manage their deer herd. Why protect the majority of yearling bucks? Yearling bucks are no more likely to be infected with CWD  than yearling does, are roughly only 25% as likely to be infected as a 3.5 year old bucks, and also only about half as likely to be infected as a mature doe. (Grear et al.  “Demographic Patterns and Harvest Vulnerability of Chronic Wasting Disease Infected White-Tailed Deer in Wisconsin”). We see similar low rates of infections in yearlings and increases in infection rates as deer get older in studies of bTB in Michigan deer.

• Minimize Yearling Dispersal If yearlings are less likely to be infected than mature deer, it is fair to ask, why should we be concerned about them at all with respect to TB or CWD? The answer is dispersal. Yearling deer disperse to new territories in spring or fall, and can take disease with them when they do. For this reason, dispersal should be considered as a part of any comprehensive approach to TB or CWD. Can we impact dispersal rates and distances to limit disease spread? In a review of research in an article titled Ready, Set, Scatter in the November 2017 issue of Quality Whitetails magazine, research from Maryland and Pennsylvania indicated Quality Deer Management (allowing most yearling bucks to survive, and harvesting more does) can reduce spring dispersals by yearling does and bucks, delay fall dispersals by bucks, and  reduce dispersal distances as well.

In a paper titled “Effect of Population Demographics and Social Pressures on White-Tailed Deer Dispersal Ecology” researchers found that after implementing quality deer management practices fall dispersal rates fell from 70% to 50% which they attributed to the presence of more older bucks reducing competition among younger bucks after QDM.

In a study titled “Population density influences dispersal in female white-tailed deer” by Lutz et al they found that during the spring dispersal was a factor of deer densities per area of prime fawning habitat. In the spring Does are very protective of their fawning territory and will kick their yearlings out. If nearby territories are also filled by protective mature does, dispersal rates and distances can be quite high. Yearling does and bucks will travel until they find habitat that is available.

Given the risk of disease spread due to dispersal of yearling bucks and does a pragmatic and effective strategy would be to delay timing of dispersal, reduce dispersal rates and reduce dispersal distances through Quality Deer Management practices and regulation changes to protect most yearling bucks while encouraging more doe harvest. These practices and regulations could delay dispersal, reduce dispersal rates, reduce dispersal distances, reduce the number of yearlings that could disperse, lower herd densities, and keep hunters hunting.

 

• Increase Landowner, Hunter, Farmer and State Partnerships QDMA Deer Cooperatives have been growing rapidly across Michigan. Research at Michigan State University has shown that these cooperatives increase hunter engagement and satisfaction. This research also shows that deer cooperative members are also far more likely to harvest does. These same deer cooperatives have established strong working relationships with their local DNR biologists, farmers and land owners to better manage their deer herds. This growth should be encouraged and partnerships further developed to enlist these influential hunter groups in the fight against deer disease. We would also like to see more QDMA Branches, Coops and other conservation groups working to improve deer habitat on state and federal lands

 

How can we have quality hunting experiences when we are significantly reducing our deer herd by killing more antlerless deer?  Are there any states we can look to that have successfully made this change?

 

Pennsylvania implemented a comprehensive program in 2002 that included liberalized antlerless seasons, antler point restrictions and a one buck rule. Today, Pennsylvania hunters are harvesting almost twice as many does per buck than Michigan hunters (1.3 vs .7), while harvesting bucks at per square mile rate similar to Michigan’s (3.1 vs. 3.4).  Due to these changes Pennsylvania hunters are also harvesting much larger bucks than ever before with state and county records dropping every year. Importantly, shifting to quality has also paid off in keeping hunters hunting. Over the past 10 years, hunter numbers have declined at a lower rate in Pennsylvania (5%) than in Michigan (14%). Antler point restrictions have also remained popular in Pennsylvania throughout 15 years of implementation consistently enjoying 60 – 70% support.

 

Nationwide, quality deer management (QDM) has become increasingly popular with polls showing 70% or greater support from hunters. While practicing QDM does not require APR regulations, in Michigan the 2016 Harvest Survey showed hunter support for Antler Point restrictions of 59%, if those expressing no opinions are dropped, statewide support is 65%. In Northwest Michigan, where antler point restrictions have been implemented, support for the regulations has grown to 77%.

 

 

We need to make the shift from quantity to quality management statewide, and we need to do it prior to the 2018 hunting season. CWD and TB will not wait for us to act. We are committed to working with the DNR, Natural Resource Commission and all other conservation and hunting groups to achieve this deer management shift.