Past, Present, And Questionable Future
White-tailed deer in Michigan’s Upper Peninsula (U.P.) are on the decline and in serious trouble. If you hunted deer in this northern region during the 2015 rifle season you know what I’m talking about.
This sharp decline in deer numbers and deer hunting success is not unique to Michigan’s U.P. According to a report by the Quality Deer Management Association, the national antlered buck harvest declined by 8 percent between 2003 and 2013, but most sharply (18 percent) in the Midwest.
These are discouraging figures, indeed, but the broad regional data do not come close to revealing the seriousness of this problem on extreme northern deer range. In states like Minnesota,
Wisconsin, and Michigan, the buck harvest dropped by 20 to 27 percent during that 10-year period.
Buck harvest figures for Michigan’s U.P. are even more dismal. The “2015 Deer Hunter Camp Survey Report” for Michigan’s U.P. tells the story: only 14 percent of the hunters reported harvesting a buck in the U.P. during the 2015 firearm season and a couple of Deer Management Units (DMUs) reported buck hunting success rates as low as 3 percent. Michigan DNR survey results indicate a 17 percent buck hunting success rate in the U.P. during the 2015 firearm season.
These figures are reminiscent of the late-1960s to early-1970s when the U.P. deer population probably dropped below 200,000 head.
The specific reasons may vary, but the results are similar across northern deer range: deer populations are steadily declining because annual deer recruitment rates fail to keep up with deer mortality rates. This simply means that not enough newborn fawns survive annually to replace those deer that die from all causes.
It’s my contention that the real bottle-neck here in the U.P. is inadequate deer wintering habitat. Deer living in northern portions (i.e., heavy snowfall) of this region typically migrate southward, to areas of conifer cover that provide shelter and receive less snow. This so-called “yarding” behavior sometimes involves long-distance migration of 50 miles or so, and results in high density deer concentrations during winter.
Many of these historic deer wintering areas, more recently referred to as “deer wintering complexes,” no longer support deer, not even during winters of only modest severity.
In addition, the shelter quality and/or food resources in many (if not most) of those areas currently being used by wintering whitetails have been severely degraded due to overbrowsing, fragmentation, and lack of regeneration.
This means the deer carrying capacity of winter range has steadily declined. As a result, regional deer numbers may rise during a series of mild winters, only to plummet during one severe winter. This has resulted in a roller-coaster trend in regional deer numbers, but the lows have become lower and so have the highs.
In my view, other management practices designed to decrease antlerless harvest, kill more predators, or improve summer range will have little long-term impact on deer abundance if the winter range cannot support them.
There are a number of consequences northern whitetails suffer due to inadequate winter habitat, including higher than normal winter losses due to malnutrition and predation. The hidden loss—excessive newborn fawn mortality—comes later.
Depending upon sex and age composition, 30 percent or more of the deer herd may die during a severe winter. More importantly, greater than 50 percent of the newborn fawns may die as a result. Because does malnourished during the late stages of pregnancy fail to produce milk, they are more likely abandon their young or give birth to weak, stunted individuals that die soon after birth. Naturally, predators (i.e. scavengers) like coyotes are quick to take advantage of this springtime food source.
Although many (including some resource managers) will disagree with me, I believe such problems can be remedied with careful planning and wise habitat management.
Clearly, winter weather severity and the quality of deer wintering habitat determine prevailing deer numbers throughout the U.P. Hence, the whitetails’ winter habitat must provide a favorable balance of food and shelter, in order to buffer the adverse effects of prolonged food shortage and ever present threat from predators during winters of deep snow.
The recent decline in U.P. deer numbers is generally contributed to three consecutive tough winters. Granted, this northern region does not provide the most friendly environment for wintering whitetails—especially so in the past couple of decades. However, I can’t accept the notion that improving winter habitat for U.P. whitetails is an exercise in futility—it all comes down to determining priorities relative to forest management.
For those that have given up on deer hunting in the Michigan’s U.P., I’d suggest you look back at historical deer records for this region to more clearly assess where we’ve been, where we are, and where we might be headed in the future, relative to deer hunting opportunities.
An understanding of the past will help lay a firm informational foundation for initiating management strategies necessary for U.P. deer population recovery. And, as they say, “hindsight is perfect.” So, we should be able to avoid making some of the same mistakes made in the past.
However, be aware of this species’ extremely flexible, adaptive, and unpredictable behavior when stressed—for example, like moving into town.
Whitetails have lived in the northern Great Lakes region for roughly 10,000 years, arriving soon after the last glaciers retreated. Since the species evolved in a more southerly environment, it’s important to recognize that deer wintering behavior is a relatively recent adaptation, and not a deep-seated genetic trait.
While some biologists suggest that deer were scarce to nonexistent throughout this northern region prior to 1850, careful analysis of pre-settlement vegetative conditions indicate otherwise. Apparently, towering virgin pines did not blanket the region.
Instead, the forest cover was broken by windfalls, wild fires and insect infestations, creating a mosaic of varied habitat that supplied, albeit spotty, favorable food and cover for deer year-round.
The best estimates indicate the U.P. pre-settlement habitat could support about 15 deer per square mile, or somewhere in the neighborhood of 240,000 deer in the 16,000 square mile peninsula. And historical events recorded in the archives dating back to 1736 support this notion.
It’s interesting to note, however, although whitetails lived along southern portions of Michigan’s U.P., some historians suggest there were no deer along the south shore of Lake Superior (i.e., in the high snowfall zone) prior to the Whiteman’s arrival.
Clear-cut and Burn
According to Michigan DNR wildlife Biologist, Robert Doepker, winter temperatures in the late 1800s until 1940 or 1950 were considerably warmer than during the previous 1,000 years. This period of warmer winter weather corresponds with unprecedented forest harvesting, burning and land clearing in Michigan’s U.P.
Logging in the late 1800s produced habitat diversity more favorable for whitetails throughout northern Michigan. Logging followed by wildfires created openings that produced hardwood browse, as well as shrubs, grasses, and herbaceous plants. In response to better nutrition, deer populations flourished.
By 1870, it was estimated that northern Michigan may have had about one million deer. If so, the U.P. probably had in excessive of 400,000 deer at the time.
According to famous photographer and naturalist George Shiras III, there were few whitetails in the deep snow country along the south shore of Lake Superior in 1850. However, he reported that 80,000 deer were taken within 10 miles of Lake Superior in 1879, 1880, and 1881. At the time, there were no seasons or bag limits and most deer were taken by market hunters. Shooting deer primarily for hides was big business during summer.
The period of deer abundance in Northern Michigan was short lived. Wildfires repeatedly swept vast areas of cutover lands, while market hunters continued to take an unlimited number of deer using snares, traps, and guns. Habitat devastation, combined with unregulated hunting, reduced deer numbers by the 1800s.
Serious deer hunting restrictions were not imposed until the late 1880s. More counties were closed to deer hunting, hunting seasons became progressively shorter, and more restrictive measures governing how deer were taken and used were adopted in 1881. (It’s noteworthy that no U.P. county has ever been closed to deer hunting).
The first Michigan deer hunting license, selling for 50 cents, was required in 1885, when the season extended from Nov. 1 to Nov. 25, with a bag limit of five deer (either sex). That year, 14,500 licenses were sold and an estimated 12,000 deer were harvested. Fewer than 13,000 hunters bagged about 12,000 deer in 1899, most of them in the U.P.
By 1900, white-tailed deer were scarce to non-existent throughout much of the United States; they were rarely hunted, because they were rarely seen. In the Northeast, Southeast, and lower Midwest, where deer were formerly abundant, they were now viewed as little more than a curiosity. By 1900, experts estimated only about 500,000 deer remained in all of North America, others place that figure closer to 350,000.
By some estimates, there were still 50,000 deer left in Michigan by 1900, most of them in the U.P.—which I suspect was an ultra-conservative estimate. The bag limit was lowered to three deer in 1901, two deer in 1905, one deer in 1915, and one buck in 1921. Despite low dear numbers, U.P. deer hunters continued to harvest 5,000 to 10,000 deer annually. At any rate, if you wanted to hunt whitetails in those days, you came to Michigan’s U.P.
It’s noteworthy that the primary predators of deer, such as wolves, bobcats, and black bears are native to Northern Michigan, and likely played an important role in pre- and early-settlement times in the U.P. Coyotes did not arrive until about 1906.
Forest fire control improved in the 1920s. The scorched cutover forest lands gradually recovered, producing excellent food and cover for whitetails year-round. By the 1930s, 40,000 or so hunters were harvesting around 20,000 bucks annually, from a deer population approaching 400,000.
During the late 1940s and early 1950s, U.P. deer experienced less winter stress than normal and benefited from logger-felled browse during winter. Winter deer-kill was minimal and pregnant does, surviving winter in good physical condition, successfully reared a high proportion of their fawns. (Note, this occurred despite the presence of notorious fawn predators, such as coyotes and black bears). As a result, by 1949, U.P. deer numbers gradually but steadily increased, approaching 700,000 (an average of 40 deer per square mile).
Meanwhile, the number of firearm deer hunters in the U.P. reached 100,000, annually, and stabilized at the level (or higher) for the next six decades, despite rather dramatic annual changes in numbers of deer available for harvest. In a 10-year period, 1940 to 1950, more than three million bucks were harvested—averaging over 27,000 bucks annually
Bust of 1970
The U.P. firearm deer harvest declined sharply during the 1960s, to an average of about 17,700 buck, annually. Without concerted management of deer wintering habitat, the productive “brushy” habitat had grown into pole-sized timber, greatly reducing range carrying capacity for deer. In addition, an overabundance of deer simply ate themselves out of house and home.
No antlerless deer were legally harvested in the U.P. from 1921 to 1955. Thereafter, special seasons allowing the harvest of antlerless deer by permit holders was initiated in an effort to balance deer numbers with available food and cover resources.
Although these special seasons created an up-roar among hunters they did little more than salvage a portion of the herd that was doomed to starvation during tough winters. During the 1960s and 1970s, annual over-winter deer mortality due to malnutrition and predation typically outnumbered the legal harvest. In addition, annual newborn fawn mortality must have sky-rocked.
By 1972, there were fewer than 200,000 deer left in Michigan’s U.P. and the annual buck harvest dropped to a modern all-time low of less than 10,000 annually during the 1971-1973 period. Surprisingly, deer hunters remained faithful to their sport.
Another Population Boom
An unusually long string of mild winters prevailed from mid-1970s to the early 1990s, when 12 of 16 winters were considered mild relative to their impact on whitetails. During this period, deer numbers in the Southern U.P. built from extremely low in the 1960s to ridiculously high in the 1990s—many areas had in excess of 100 deer per square mile.
Other factors also came into play during this period favoring deer population growth, such as a 250 percent increase in pulpwood harvest, much of which occurred during winter. There was also a 15-fold increase in the acreage of corn grown for grain, which deer scavenged. Supplemental feeding and baiting for hunting purposes also became popular.
Although this produced short-term benefits, long-term consequences were on the horizon. By 1995, the U.P. deer herd reached an all-time peak of more than 700,000 probably double the desired number. That year, hunters in the U.P. harvested a record 115,501 deer (including 47,633 antlerless deer) during the firearm, archery and muzzleloader seasons combined.
Despite the record high harvest, however, more than one-half million deer were left to crowd into winter habitat capable of supporting less than one-half that number. Given the circumstances, the stage was set for the disaster that followed.
Disaster In The 1990s
Snow cover and cold temperatures triggered deer migration to wintering habitat throughout the U.P. during November 1995. Deep snow quickly followed, locking deer in heavy cover by late December. There was no let up, holding a ridiculously abundant deer herd in conifer cover that had been browsed-out and heavily fragmented by excessive logging, until late April, or in some cases until early May.
Spring surveys conducted by Michigan DNR biologists confirmed early predictions: an estimated loss of nearly 200,000 deer in the U.P. alone—an average of roughly 12 deer per square mile, nearly twice the 1995 record harvest. Although data were not available, it’s safe to say that surviving malnourished pregnant does probably lost 60 to 70 percent of their newborn as well—coyotes and bears merely scavenged the dead and dying.
The next winter was only a trifle easier. And, although the wintering herd was smaller, spring surveys determined that about 110,000 deer perished during the 1996-97 winter. Satellite groups of wintering whitetails that had formerly survived in poor quality shelter quickly vanished.
In the short-term, these data show how fast a northern deer herd can respond to either favorable or unfavorable circumstances. For example, the U.P. deer herd increased from 395,000 deer in 1987 to 700,000 or so in 1989, a 44 percent increase in just two years. Conversely, following tough winters, as occurred in 1995-96 and 1996-97, herd size dropped from roughly 725,000 deer to 474,000 deer, a 34 percent decline in two years.
Given easy winters, the annual U.P. buck harvest more than doubled during the next 3 firearm seasons. In 2000, 41 percent of the hunters harvested a buck, resulting in a harvest of nearly 51,000 bucks—many were convinced the worse was over, but not so.
Since 2000, U.P. deer numbers have undergone minor periods of “boom and bust”—governed chiefly by the severity of winter weather. However, given the poor condition of deer wintering habitat, deer population lows have become lower and so have the highs, leading to a steady decline in regional deer numbers just as some of us had predicted more than 15 years ago. Remember, one of the most important factors leading to the overabundance of U.P. whitetails in the early 1990s was the preponderance of mild winters (12 of 16) leading up to that period. Hence, back then, high quality wintering shelter was not necessarily a critical factor and the winter deer herd had access to an abundant food supply provided by winter logging and resultant growth of natural browse.
A reduction in logging activity, maturing forest cover, clean corn harvesting, fragmentation of protective conifer cover used by wintering whitetails, and more frequent severe winters (12 of 21 since 1996), have contributed to a steady decline in deer numbers throughout the U.P. When hit with a hard winter, the deer herd no longer bounces back quickly in response to a couple of mild winters, simply because the poor quality deer wintering habitat is not conducive to such sudden response.
Most recently, back-to-back severe winters in 2007-08 and 2008-09, and again in 2013-14 and 2014-15, erased short term deer population gains following easy winters.
In 2009, for example, the deer population dipped to about 247,000 deer, close to that calculated for the region before European settlement. The firearm buck harvest of 19,178 that season was the lowest harvest by U.P. deer hunters in three decades. Since then, the firearm buck harvest success rate has averaged about 23 percent, annually, compared to an average success rate of 33 percent during the period 1985-2008.
In 2014 and 201 5, the U.P. firearm buck harvest was even lower, 14,734 and 13,276, respectively. Due in part to heavy pre-firearm-season snowfall, only about 73,000 hunters participated in the 2014 hunting season. However, even with mild weather, only about 76,000 hunted the U.P. in 2015.
These hunter participation rates are similar to those in 1945. Historically, we’ve witnessed rather dramatic ups and downs in U.P. deer numbers, but never before have we experienced such a dramatic corresponding drop in hunter numbers.
The winter of 2015-16 was one of the easiest for whitetails in this region for many years, assuring maximum winter deer survival as well as excellent newborn fawn survival in 2016. Given a couple more consecutive mild winters, we are likely to see modest gains in deer numbers and hunter success. But one tough winter will wipe out all such gains.
Currently, there are probably fewer deer in Michigan’s U.P. than there were during pre-settlement times, despite over 100 years of deer management. Needless to say, those hunting this northern region are not particularly happy, and many are choosing to hunt elsewhere (or possibly not at all).
Things are not likely to change a great deal for U.P. deer hunters in the near future, because deer numbers here will continue to be governed by the severity of winter weather and poor status of deer wintering habitat.
Nonetheless, there is some hope for a brighter deer hunting future in Michigan’s U.P. Finally, there are some comprehensive plans to more effectively manage critically important deer wintering complexes throughout this northern region—a subject deserving considerably more discussion.