- In the Wild - Dung beetles - they dance, communicate with the stars & clean up the poop
By Carolyn B. Edwards BCC Staff Writer
One of the problems with broadcasting insecticides is that good bugs are killed right along with the irritating ones. One of those good bugs is the dung beetle, aka tumblebug. Dung beetles are found throughout the world, except in Antarctica. Indeed, some species are descended from the sacred scarab of ancient Egypt.
Tumblebugs are the waste collectors of the planet, estimated to remove as much as 80 percent of mammal excrement in our pastures and fields. They are, as the joke goes, "Number 1 in the number 2 business!"
The dung beetle found most commonly in Texas is Phanaeus vindex MacLachlan.
According to the entomologists at Texas A&M University "Males and female beetles are between ½ and 1 inch long and overall metallic blue-green and copper. The front of the head is flattened and golden bronze. The male has a long, curved horn extending from the front of the head (clypeus) while the slightly larger female has a tubercle. The front legs are modified for digging."
There are several other tumblebugs in the state that also play a key role in recycling animal feces. Some are small, dark dung-feeding scarab species. "One species, Onthophagus gazella Fabricius, was introduced by USDA scientists in the 1970s and is now common throughout the state," said A&M.
Most species are dull to shiny black and 1-3/8 inch or less in length with wing covers (elytra) that may have ridges (striae). They are often attracted to lights at night.
Pairs of adult males and females dig deep burrows underneath animal excrement in which they bury portions of the droppings. Eggs, deposited in the excrement, hatch and C-shaped grubs (larvae) feed on the dung. The grubs develop through several stages before pupating within cells in the remains of the excrement.
According to scientists, "animal excrement is rich in insect fauna and can yield these strikingly beautiful beetles. Beetles can be washed to remove debris."
Dung beetles play an important role in nature: reducing fecal material in nature and thereby reducing the habitat for filth-breeding flies. Consequently they are considered beneficial and medically harmless.
According to National Geographic for Kids, there are probably 6,000 species, or kinds of dung beetles. They belong to three basic groups: rollers, tunnelers, and dwellers, which describe how the beetles use the dung they find. Rollers shape pieces of dung into balls and roll them away to bury for later snacking or to use as a place to lay their eggs. Tunnelers bury their dung in tunnels dug underneath the pile of poop. Dwellers live inside dung piles. Since the tunnelers and dwellers keep themselves hidden, it's the rollers we most often see here in Texas. Rollers make up about 10 percent of all tumblebug species.
The beetles enjoy munching on the undigested bits of food found in dung. The larvae tend to eat the solid bits, while the adults favor the nutritious liquids.
The world's largest dung beetles grow up to two and a half inches long. They can live up to three years. They can bury 250 times their own weight in dung in one night's work.
Dung beetles have a bit of a criminal nature. As a beetle rolls his ball toward home, other beetles often try to steal it.
According to South African scientist Marcus Byrne, the 10 percent of dung beetles that are rollers find their way home using cues from polarized light from the stars. Take the time to watch his talk on the Dance of the Dung Beetle on TED.com. You'll forever look at these little insects with nothing less than amazement!
Pictured: Photo by Judith Pannebaker
A congregation of dung beetles gather up the remains of a tasty Hill Country cow plop in order to roll it all home for safekeeping and snacking.