17 Feb Astonishing numbers of dung beetles
What’s in a pile of elephant dung? Well, besides the usual grass, bark and sticks, researchers in East Africa recently counted an astonishing 13 699 individual dung beetles in a single 1kg (2.2 lbs.) pile of fresh dung.
This means that a large elephant, which can produce as much as 160 kg of faeces every 24 hours, could provide food for as many as 2.13 million beetles in a day.
The are about 790 species of dung beetles found in Africa, ranging in size from a few millimeters in length to blockbusters measuring 45 mm or more. Their breeding and feeding habits vary but the most famous are those that shape the dung into balls and roll it away to be buried and used as nesting sites.
Dung beetles, as their name suggests, eat dung, but usually consume only microscopic particles of the waste. The larger the pile of dung the more likely it is that there will be a wide variety of beetles feeding on it, each species consuming the matter which they have evolved to eat.
Contrary to popular thought only about 10% of dung beetles shape the dung into balls, the majority taking the easier route of making tunnels under piles of dung where they lay their eggs. Both methods ensure that once the eggs hatch the larvae have a ready source of food.
Most species utilise the dung of herbivores although some feed on the faeces of carnivores and omnivores.
The beetles play a critically important ecological role in spreading dung, which is in reality is much needed fertilizer, into the soils across the grasslands and woodlands of Africa. This process also helps with the dispersal of seeds in the dung.
The ecological roles of the beetle and elephants are inextricably linked.
“The decline or extinction of elephants, at least in East African grasslands, may have a massive cascade effect on the populations of coprophagous beetles (dung beetles) and the biota dependent on or gaining an advantage from them,” researchers Frank-Thorsten Krell and Sylvia Krell-Westerwalbesloh from the Denver Museum of Natural Science, state in the new paper published in January 2024.
The study was undertaken in the Laikipia-Samburu region during the rainy season and the number of beetles may vary widely according to the season, habitat, and geographical location.
