Dung beetles came late in my soil health journey. More than three decades after becoming an “organic” farming advocate, the dung beetle has become for me the absent narrative in the sustainable agriculture movement. While the environmental and economic benefits of well managed grazing systems have long been touted, lost in the discussion has been the role of dung beetles as the keystone species of the dung pat ecosystem, the biological fuel of many of our native ecosystems.
Dung beetles play three major roles in ecosystem function:
Break down dung piles and help to cycle nutrients for improved soil fertility
Serve in secondary seed dispersal by moving seed deposited in the dung pat by the ruminant
Reduce the survival rates of parasitic nematodes and flies
While research shows some 87,000 species of insects utilize dung pats, dung beetles tend to be the first to colonize fresh ones, feeding on the liquid portion of the manure. They lay eggs in or under the pat and when the larvae hatch they feed primarily on the fibrous matter. While dung beetles make a small portion of the insects in a dung pat, around 3%, they have a much larger impact.
There are three basic types of dung beetles: dwellers, tunnelers, and rollers.
Dwellers spend their entire life cycle in the dung pat. They play an important role in creating holes and tunnels within the dung pat to give other insects access. Some of these other insects are beneficial species that predate on flies and other parasitic insects.
Tunnelers create tunnels in the soil under the pat. They transport dung underground and lay their eggs in burrows where the larvae feed on the fibrous, undigested portion of dung.
Rollers are the iconic species that roll dung into balls and bury them away from the dung pile. While they play an important role in many ecoregions, they are less common in Minnesota and if you see one of these species here you are fortunate.
Opportunities to Restore Natural Ecosystems
For me, dung beetles represent the complexity and interconnectedness of our natural ecosystems. As we’ve consolidated agriculture into larger, specialized production systems, we’ve broken the natural cycles that allowed ecosystems to function. Livestock are pushed for yield, with little value placed on their excrement, or the dung beetle. Grazing systems that mimic the natural relationship between herbivores and native ecosystems turn livestock and their excrement into assets, much to the pleasure of the dung beetle.
SPECIAL EVENT: Learn More About Life in a Dung Pat
Join us on August 24th, 2023 for an afternoon pasture walk in the Pine River area with Dr. Roger Moon, retired University of Minnesota veterinary entomologist. Hosted by the Crow Wing River Basin Forage Council, a networking group of the Sustainable Farming Association, the pasture walk will involve discussion on the role of dung beetles and best management practices to use to protect dung beetle populations when using dewormer medication. We will be breaking into small groups to dissect dung pats and collect insects from different age pats, then coming together as a group to identify the insects collected. Join us to learn more about life in a dung pat.
Cost is $10
For more details, or to register go to https://sfa-mn.org/forage-council/