Ipsa Tripathy
Bhubaneswar: Animal dung is usually regarded as waste. In nature, however, it is a resource that supports a surprisingly diverse community of organisms. A single dung pat can become a temporary habitat for insects, mites, nematodes, fungi and microorganisms, each interacting with the others as decomposition progresses. This small ecosystem plays an important role in nutrient cycling and soil processes. Among its most visible inhabitants are dung beetles, but they represent only one part of a much larger biological community.
Dung Is a Temporary Ecosystem
Fresh animal dung contains organic matter, nutrients, microorganisms and undigested plant material. Its chemical composition varies with the animal species, diet, age of the dung and environmental conditions. Once deposited, dung begins to change rapidly. Microorganisms start breaking down organic compounds, while insects and other organisms arrive and feed, reproduce or use the dung as shelter.
Different organisms occupy different stages of decomposition. This creates a succession of biological communities rather than a single, permanent dung community. Among the organisms associated with dung are flies, beetles, mites, nematodes, fungi and bacteria. Dung beetles themselves may also interact with parasites and other organisms living within the dung.
Dung Beetles Are Important Ecosystem Engineers
Dung beetles are among the best-studied organisms associated with animal dung. Many species feed on dung as adults, while others use it to provision their developing larvae. They generally fall into three broad behavioural groups: rollers, tunnelers and dwellers. Rollers form portions of dung into balls and move them away from the original dung pat. Tunnelers bury dung beneath the surface, while dwellers remain within or immediately beneath the dung.
These different behaviours influence how quickly dung is removed and where nutrients are deposited. Their activity also physically changes the soil. Burrowing and dung burial can increase the movement of organic material into the soil, modify soil structure and create pathways that can improve water infiltration and root growth. For these reasons, dung beetles are often described as ecosystem engineers.
A Natural Nutrient-Recycling System
Dung contains nutrients that originated in plants and passed through an animal’s digestive system. When dung remains on the surface, these nutrients are released gradually as microorganisms and other organisms decompose it. Dung beetles can accelerate this process by removing and burying dung.
Their activities redistribute nutrients such as nitrogen and phosphorus into the soil. This can make nutrients more accessible to plants and contribute to nutrient cycling within terrestrial ecosystems. The effect is not identical everywhere. Soil type, climate, dung composition, beetle species and beetle abundance can all influence the outcome.
The Dung Community Is Larger Than the Beetles
Dung supports organisms from several biological groups. Flies use dung as a food source or breeding substrate. Their larvae develop within decomposing organic material, where they interact with microorganisms and other invertebrates. Mites can also occur in dung communities. Some species feed on organic material or microorganisms, while others are associated with insects such as dung beetles. Certain phoretic mites use beetles for transportation between dung resources and may prey on fly eggs and larvae.
Nematodes are another important component. Some are free-living organisms associated with decomposition, while others are parasites whose life cycles can involve animal dung. Fungi and bacteria are fundamental to decomposition. They break down organic compounds and transform nutrients into forms that can re-enter soil processes. Together, these organisms form a food web inside and around the dung.
Dung Beetles Can Influence Plants
The ecological effects of dung do not end with decomposition. When dung beetles bury dung, they place organic material and nutrients below the soil surface. Their tunnels can also modify the physical environment around the buried material. Some dung beetles contribute to secondary seed dispersal. Seeds present in animal dung can be relocated when beetles move or bury the dung. This can influence where some plants germinate.
A 2024 meta-analysis of studies examining dung beetles and plant growth found an overall positive effect: across the analysed studies, dung beetle activity increased plant growth by an estimated 17%, although the effects varied substantially among individual experiments. This variation shows that dung-beetle effects depend strongly on ecological context.
They Can Also Affect Parasites and Flies
Dung is an important environment for the development of several organisms that have parasitic relationships with livestock and other animals. By consuming, relocating and burying dung, dung beetles can alter conditions experienced by parasite stages. Experimental evidence indicates that dung beetles can reduce the availability of some gastrointestinal nematode larvae, although the magnitude of this effect varies and cannot simply be assumed to occur in every ecosystem.
Dung beetles can also influence fly populations. Their feeding and burial activities change the physical and biological conditions of dung, while mites transported by beetles can prey on fly eggs and larvae.
Biodiversity Within a Small Space
The ecological importance of dung illustrates a broader principle of biodiversity: habitats do not have to be large to support complex communities. A dung pat may exist for only a limited period, but during that time it can provide food, shelter and breeding opportunities for numerous organisms.
The diversity of these communities also varies with the surrounding environment. Dung beetle communities, for example, respond to factors including temperature, water availability, vegetation structure, soil properties, competition and predation. Changes in land use can therefore alter the organisms associated with dung and the ecological functions they perform.
Why This Small Ecosystem Matters
Animal dung is part of the natural movement of nutrients through ecosystems. It connects animals, plants, soil and microorganisms. Removing dung from an ecosystem, changing the animals that produce it, or reducing the organisms that process it can alter these ecological pathways. This is particularly relevant in grasslands, forests and agricultural landscapes where dung-associated organisms contribute to decomposition and nutrient cycling.
What appears to be waste is therefore part of a functioning biological system. A closer look at animal dung reveals a community that is rarely noticed: insects moving through it, microorganisms decomposing it, mites interacting with other organisms and beetles carrying nutrients into the soil. Dung is not simply the end product of digestion. In an ecosystem, it becomes the beginning of another cycle of life.