Not far south from our study area along Hwy. 53 there's a new billboard with a spotted and spindle-legged deer fawn standing alert and angelic in summer grass. In the image, the forest edge beyond the fawn appears as if on fire, with glowing sparks and embers flying from blurry flames that fade right to left into a smoky then charred background that highlights yellow letters stating: "Wolves devour over 54,000 fawns a year in Minnesota."
What's the point? Let's ignore that the "over 54,000" figure is likely an overestimate. Visually, the billboard makes a plea to save helpless Bambi from ending up in the belly of a wolf. The background message is that wolves are just as big a threat to fawns as forest fires. The statement is meant to be sensational: Wolves aren't just trying to survive and feed their pups, they devour deer. Baby deer. 54,000 baby deer a year, right here in Minnesota.
The billboard's appearance is well-timed and placed along the northbound lane to anticipate the fall hunting seasons and appeal to hunters traveling up to deer camp in coming months. Those who paid for the billboard, the Minnesota Deer Hunters Association-Sturgeon River Chapter, write on social media that the point of the message is: "We support wolf management. The wolf numbers are over the states [sic] recommended projections for a healthy wolf population, yet no wolf hunt."
Set aside the fact that policy to not hold a hunt is a form of wildlife management and that Minnesota wolves are federally protected currently, precluding state wolf hunts. Billboard supporters would have you believe that hunting wolves would surely help more fawns survive. But this stands in stark contrast to the best available science and instead makes the faulty assumption that if a wolf doesn't devour a fawn, that fawn survives.
A fawn not eaten by wolves might get shot by hunters. Over the past five years, deer hunters have reported to the Minnesota Department of Natural Resources that they have killed an average of about 25,000 fawns annually. A fawn not eaten by wolves might be among the 40,000 or more deer hit by vehicles in Minnesota each year. Or maybe it will be eaten by a coyote or bear, or slowly starve, or get killed by a combine in the first hay cutting, or be moved by humans and abandoned by mom, or die from a viral disease that is spreading north and is uncontrollable, such as epizootic hemorrhagic disease.
Fawns die from many causes and the causes of mortality can compensate for one another. Increased mortality due to one cause often means less mortality from a different cause. And yet — very importantly here — the overall rate of fawn survival can remain unchanged.
Put another way, if bears and coyotes don't get them, wolves and hunters will, and the same number of fawns will survive either way.
There is appealing, persistent and faulty thinking that because predators kill fawns, fewer predators will increase fawn survival. Research examining fawn survival amid wolves in Michigan, Minnesota and Wisconsin shows that between 45-49% of fawns survive summer months. The average survival rate of fawns in North American forests when examined across 30 populations in 16 states was 41%, with the lowest survival rates occurring in areas without wolves. Even in some areas free of predators, only 44% of fawns may survive past three months.
Our point is that the billboard's message is propaganda and its connection to wildlife management is logically flawed and not supported by the best available science.
The life of a deer fawn is perilous regardless of whether any of their predators are hunted or trapped, and sometimes even if there are no predators around at all. The majority of fawns will die, regardless of the cause. Some say fawns are born with a hoof or two in the grave.
Wolves eat deer fawns, lots of them. But that does not mean recreational wolf hunting or trapping of wolves would increase fawn numbers.
Joseph K. Bump (email@example.com) is Gordon W. Gullion Endowed Chair in Forest Wildlife Research and Education at the University of Minnesota and director of graduate studies in conservation sciences at the University of Minnesota. Thomas Gable is a postdoctoral researcher.