Emmet County. Deer Management Unit

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1 024 Emmet County Deer Management Unit Area Description Emmet County Deer Management Unit is in the Northern Lower Peninsula Region (NLP). It has roughly 80,371 acres of public land which is about a quarter of the total acreage in the county. The remainder of land is in private ownership. Topography varies from rolling hills to areas that are relatively flat. Soil types consist mainly of sandy types that are well drained. The landscape is primarily rolling hardwoods interspersed with private inholdings and agriculture in the south. Deer densities are relatively stable with higher concentrations of deer in the agricultural areas in the south and along the Lake Michigan coastline. Deer numbers vary greatly in the upland hardwoods depending on food sources, mainly hard mast. Management Guidance: Two main goals guide the deer management in this DMU: 1) impact management; and 2) hunting opportunities. Impact management refers to reduction of undesirable effects associated with deer over-abundance. Crop damage, deer-vehicle collisions, and poor forest regeneration due to over-browsing are examples. In an effort to find a middle-ground in which deer numbers provide ample hunting and wildlife viewing opportunities and mitigate unwanted impacts, we review data from several sources to adjust the harvest strategy as needed. These data include deer harvest data from check stations and an annual survey, the winter severity index, deer-vehicle collision data from the Michigan State Police, and deer-related information collected by regional wildlife biologists (e.g., number of Crop Damage Permits, spotlight surveys, habitat assessments, etc.). Deer Harvest Analysis: Buck harvest has oscillated between 2 and 4 bucks harvested per square mile consistently over the last decade. The fluctuations observed are likely a combination of varying winter severities. Both the antlered and antlerless harvest indicates that the population is likely stable to increasing. While it can be difficult to pinpoint exactly what is causing a population to increase or decrease we can make predictions based on past trends and looking at a number of factors that can indicate changes in populations.

2 In northern Michigan, winter severity has a direct impact on deer condition at the population level. Whereas mild winters allow for better survival of deer, severe winters can cause high deer mortality. In addition does may abort fetuses in order to survive which creates a lag effect into the following year. Winter severity has been low over the last four years compared to the average trend for the area. The mild winters observed over the last four years have allowed for a steady increase in the deer population since the last hard winter of 2008/2009. Additional Population Assessment Factors: Deer Management Assistance and Crop Damage Permits OOS & DMAP Permits DMAP Issued DMAP Used OOS Issued OOS Used Deer Management Assistance and Crop Damage Permits increased in 2009 and have remained stable over the last four years. Most of these are used to target higher density spots in the DMU.

3 Deer- Vehicle Collsions Deer-vehicle collisions (DVC) are commonly used as an index to the deer population trend, the idea being that high rates of DVCs are correlated with high deer populations, and vice versa. Research has shown that there are other factors that influence the rate of DVCs. Habitat proximate to the roadway and highway characteristics can blur the relationship between deer population and DVCs. However, DVC data can provide useful information if contextualized as one part of a deer population assessment. These data are provided by the Michigan State Police. Although changes may have occurred in law enforcement response and recording of DVCs over time, we assume they have remained consistent enough to provide an accurate estimate of DVC rates relative to vehicle miles driven. The various fluctuations from year to year give supportive evidence to the primary driving factor of the deer popualtion which is winter. Signigicant drops in DVC occurred one to two years after a particularly severe winter.

4 Deer Hunter Numbers and Behavior Hunter trends can be an important indicator to assess if the number of hunters may be driving populations up or down. Hunter numbers have steadily decreased over the last decade as has hunter effort. However, the number of antlered deer harvested per unit of effort has increased. This indicates that harvest is not dependent on the number of hunters. The years of low harvest have followed years of high winter severity in DMU 005 and the same goes for years of high harvest have followed patterns of lower winter severity indicating that harvest is more likely driven by the severity of the previous winters Hunter perceptions and goals can also impact harvest numbers. Large scale shifts in hunters decisions to target older deer and pass on younger bucks results in reduced harvest numbers and increased hunter effort, as there are fewer deer in older age classes. Success and harvest rates are thereby suppressed not by population decline, but by human decision-making processes. Similarly, hunters may self-regulate harvest of antlerless deer for a variety of factors, such as a perception of too few deer. DMU 024 is one the 12 counties included in a new antler point restriction area. Starting in 2013 hunters are restricted to harvesting a buck with at least 3 or more points on one side. As a result of this it is anticipated that there will be a drop in hunter success in the 2013 deer harvest but hunter success is anticipated to rebound in 2014.

5 Deer Condition Data: Yearling main antler beam diameter, measured just above the burr, and number of points are useful for determining deer body condition. These measurements are recorded by MDNR as hunters voluntarily present harvested deer at check stations throughout the state. When aggregated by DMU, the average antler beam diameter and number of points for yearling bucks over multiple years is calculated. An upward trend indicates improving herd condition, whereas a downward trend points to declining herd condition. Generally, herd condition is a function of environmental and landscape factors. An abundance of highly nutritional food resources and good cover is beneficial for herd condition. Depletion of these resources through overpopulation leads to a decline in herd condition, observed as low yearling main beam diameters and antler points. In northern Michigan, winter severity is has a direct impact on deer condition at the population level. Other environmental factors may impact deer condition indirectly, though. A late frost or an especially rainy spring can negatively influence soft and hard mast crop production which is a major source of nutrition in this DMU. Likewise, changes in land use practices can affect cover and food resources. Beam diamerters in DMU 024 have had little fluctuation over the last ten years indicating stability within the herd. What fluctuations have been observed can be attributed to environmental factors such as winter severity and food abundance such as mast production.

6 Deer Management Recommendations: Population has remained relatively stable the last five years. There are more deer on the agricultural land and along Lake Michigan coast than on the forested private and public land. The overall deer popultion is relatively stable with a goal to decrease the deer numbers in the higher areas. There still is not an over abundance of antlerless deer on public land with very little browse observed. This years severe winter is likely to impact overall deer populations. The last severe winter was 2008/2009 and deer populations sustained due to the higher populaitons and better habitat on the west end of the county. It would be recommened to lower antlerless permits on both public and private lands, but because of a need to compensate for a potential decrease in buck harvest due to a second year of APR s this decrease will not be as substantial as it was after 2008/2009. Private land qouta's will be augmented with DMAP's and DCP's when appropiate.

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