These industrious beetles are in the family of beetles called scarabs. Many of us are familiar with the significance of the dung rolling scarab beetle in Egyptian historical culture. The activity of rolling dung was thought to be a symbol of Ra rolling the sun across the sky each day. Scarabs, especially the dung rolling variety are depicted in Egyptian culture often and for many reasons. In Gothland, Sweden’s largest island it was believed that if you encountered a dung beetle on its back and righted it, you would be purged of all sin. In African folklore it is told that butterfly and dung beetle were best friends. One day while resting in the shade, first man and first woman came by. They admired the butterfly but ignored the beetle. After declaring to the butterfly that he did not like being ignored, the butterfly encouraged the beetle to become the strongest beetle ever. The beetle worked hard to gain strength and once again first man and first woman came by. They witnessed the feats of strength the beetle exhibited by rolling his dung ball. They were so impressed that for the first time they ignored the butterfly it all its beauty. The beetle was so proud of his accomplishment that to this day he continues to roll dung. While this may be folklore, the strength of the dung beetle is in fact quite remarkable. Most can move ten times their weight, and one species in particular can move 1,141 times its own weight! That would be like an average sized man pulling six double decker buses full of people!
Most of us have watched a video or two of these beetles racing across the landscape rolling their prized ball with them at what seems like remarkable speeds when moving something so cumbersome. They are not trying to set land speed records, these energetic movers are trying to protect their ball from lazy dung rollers who mean to steal their hard work.
The tunnelers on the other hand dig a burrow right below the cake and bury it in place. The dwellers took the easy route and just live inside the cake. These beetles utilize the dung of herbivores and omnivores with the former be their preference. Plant material is difficult to digest in its entirety which means bits, and pieces are passed through the digestive track of large herbivores such as cattle or in Africa it is often elephants and rhinos. The indigestible bits are then deposited inside a nutrient rich pile of poo that dung beetles find quite tasty. This habit of eating leftover plant material out of fecal matter also gives them clout as seed dispersers. As they roll the prized dung ball across the landscape and bury it, seeds are transferred to new locations and often sprout into new plants. Because dung contains all the nutrients and moisture these beetles need, they do not seek other forms of food or water. However, there are some species of these beetles that prefer fungi and decaying fruit.
All three types use dung as a food source for their offspring. Eggs are laid within the fecal matter, and when the eggs hatch the larvae feed on the provided meal. In the case of those that bury the dung, often both parents stay with the offspring and guard them from potential predation. Once the larvae form pupas the parents eat much of what is left of the dung ball.
In our area they are most likely to occur in feed lots where cattle are kept or in pastures with horses or cows. But worldwide may be found in a wide variety of habitats including deserts, woodlands, savannas and grasslands.
These beetles are important components in the environment, and they play a significant role in breaking down organic matter (dung) and returning it back to the soil as a nutrient rich substance. They aerate the soil, compete for underground nesting sites with several different species of flies, as well as remove the availability of dung for the flies to feed on or lay eggs in at the surface (which greatly reduces the fly populations). Thus reducing the number of flies that pester your livestock, keeping them healthier. Their habits add nutrients back to the soil which helps prevent pasture fouling. Pasture grasses will yield better stands and provide more fodder for cattle and horses, thus reducing the amount of hay that needs to be purchased to supplement their diet. Not to mention an estimated 380 million dollars annually is saved in the cattle industry by these beetles and their dispersal of dung. The use of chemical control of flies in cattle lots has had a dramatic impact on populations of dung beetles. Many individuals are beginning to understand the detrimental result of this practice and have eliminated the use of such chemicals or have greatly reduced the amount used. Chemicals that kill flies often kill beetles and many other insects.
There are species that navigate using the milky way, still others that use moonlight to traverse their habitats. They occur on all continents except Antarctica. These unique beetles are beneficial by aiding in a healthier environment for all of us. They should be encouraged and marveled at, and never destroyed. If you want a chance to watch these beetles in action, they are more active in the late evening and nighttime hours. Grab a flashlight and head to the nearest pasture, scan the piles of dung and you may just get to see one of these beetles forming and burying their dung ball.
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