By Nancy Warren
I have been conducting free educational wolf programs across the Upper Peninsula and Wisconsin for nearly 30 years. Mostly, the rooms are full of those who want to learn about wolves but occasionally, there is someone sitting in the back with arms crossed, shouting “What good are they?” I am glad to respond. Wolves provide ecological, economic, and intrinsic benefits.
Wolves trigger what is known as a trophic cascade – a top-down interaction between predators and prey which ripples through the food web. Where there are wolves, there is greater biodiversity. A current example of this happening right now has been reported in Yellowstone National Park, where the presence of wolves is helping increase the beaver population and bring back aspen and vegetation.[1]
The destructive impacts of deer browsing on forest regeneration and vegetation is well documented.[2]
White-tailed deer, though treasured by hunters, can and do have a negative impact on forest sapling growth and native wildflower diversity. This can lead to direct effects on insects, birds and other species.[3] Insects and bird populations have been decreasing for a myriad of environmental factors, and their numbers, like all species, matter for a balanced ecosystem and life in general.
Deer can cause serious damage to newly planted seedlings and established trees. When they browse the buds, they reduce growth rates; nipping the tree at the base can create multiple stemmed trees. People who plant trees in their yard see a close-up example of this in the winter if their trees are not protected by fencing. This is also what happens to young trees in the wild.
Wolves alter deer behavior. In high wolf areas, deer spend less time foraging, which allows for tree regeneration (cedar, hemlock, and oak) and better quality trees.[4] When there are wolves, grounds can host a greater variety of wildflowers, which in turn attracts insects, butterflies, and birds. Nesting birds benefit as well, as the thick foliage helps them avoid predation from eagles, hawks, raccoons, and skunks.
Deer compromised by old age, injury, disease, and those in a weakened state due to our harsh winters are easy prey and wolves are adept at identifying these animals simply because they are easiest to catch.
While CWD and other diseases are spreading throughout the deer population down state, only one case of CWD has been documented in the U.P. Though more research is needed, there is evidence that wolves may limit the spread of CWD as wolves can detect CWD at an earlier stage of the disease. As a result, wolves help maintain healthy deer populations.
According to a US Fish and Wildlife Services report, wildlife watching in Michigan is a $1.6 billion industry. People from around the world visit Yellowstone National Park specifically to view wolves, bringing $35 million annually to the local economies.
While seeing wolves in Michigan is a rarity, I personally have led many groups, who have spent thousands of dollars coming to the Western U.P. in search of wolf sign and the hope of hearing wolves howl. For me, it is a thrill every time I hear wolves, but it is especially rewarding to see the reactions of others hearing a howl for the first time. There have been times when my groups have heard no howls in response, yet individuals were still content knowing they were in an area with a population of wolves. They leave with promises to return.
Footnotes:
[1] Farquhar, Brodie.”Wolf Reintroduction Changes Ecosystem in Yellowstone.” Yellowstonepark.com June 30, 2021. https://www.yellowstonepark.com/things-to-do/wildlife/wolf-reintroduction-changes-ecosystem/ Accessed November 8, 2021.
[2] Callan, R., Nibbelink, N.P., Rooney, T.P., Wiedenhoeft, J.E. and Wydeven, A.P. (2013), “Recolonizing wolves trigger a trophic cascade in Wisconsin (USA)”. J Ecol, 101: 837-845. https://doi.org/10.1111/1365-2745.12095
[3] Rooney, Thomas P., Waller, Donald M. “Direct and indirect effects of white-tailed deer in forest ecosystems,” Forest Ecology and Management, Volume 181, Issues 1–2, 2003, 165-176, https://doi.org/10.1016/S0378-1127(03)00130-0.
[4] Bouchard, K., Wiedenhoeft, J. E., Wydeven, A. P., & Rooney, T. P. (2013). “Wolves Facilitate the Recovery of Browse-Sensitive Understory Herbs in Wisconsin Forests”. Boreal Environmental Research, 18 Supplement A, 43-49. https://corescholar.libraries.wright.edu/biology/211