A hybrid colony of Coptotermes termites. A king C. gestroi (nutty-brown abdomen) is shown on the left, and a queen C. formosanus (orange abdomen) on the right. They are surrounded by their hybrid offspring, including eggs, larvae, workers, and soldiers. Photo by Thomas Chouvenc, University of Florida /IFAS.
Author Richard Levine is Communications Program Manager at the Entomological Society of America and editor of the Entomology Today Blog.
Formosan subterranean termites (Coptotermes formosanus) and Asian subterranean termites (Coptotermes gestroi) are the most damaging pest species in the world. Both are highly invasive and have spread throughout many areas of the world due to human activity, and their distributions overlap in some areas.
Hybrid Termites
Now scientists in Florida have observed Formosan males mating with Asian females — in fact, they seem to prefer the Asian females more than females from their own species — and their hybrid offspring seem to grow colonies twice as fast as their parents. Their findings are published in the journal PLOS ONE, and are described in this video.
Many hybrids are unable to reproduce (the mule, for example, which is the sterile hybrid offspring of a male donkey and a female horse). And many hybrids that actually can reproduce tend to lose vigor after one or more generations, which is why farmers often buy new hybrid seeds each growing season.
Richard Levine
But so far that doesn’t seem to be the case for these termite hybrids. In the laboratory, the Florida researchers are raising a hybrid colony that is growing twice as fast as same-species colonies, suggesting a potential case of hybrid vigor.
“Our hybrid colony is still showing high vigor, can potentially live up to 20 years, and can still cause a significant amount of damage,” said Dr. Thomas Chouvenc, a co-author from the UFL’s Ft. Lauderdale Research and Education Center.
While these laboratory observations remain to be confirmed in the field, the results still raise a concern about the hybridization of these incredibly destructive pests, which could have significant economic impacts, according to the authors.
To get an idea of how potentially destructive they could be, watch this video of University of Florida researchers observing both termite species swarming and mating simultaneously.
TO ALL GEORGIA STRUCTURAL PEST CONTROL LICENSEES, INTERESTED PERSONS AND PARTIES:
The Georgia Department of Agriculture (GDA) and Georgia Structural Pest Control Commission (SPCC) announce new guidance and policy to assist the industry with compliance with the current rules of the Georgia Structural Pest Control Act. The compliance fact sheets are posted under guidance policies on the SPCC webpage.
Sharon Dowdy is a news editor with the University of Georgia College of Agricultural and Environmental Sciences
Termites feeding on pieces of wood in garden soil. Image credit: Sharon Dowdy
Those who tackle termites may think the tiny insects spend their days eating wood. But a University of Georgia entomologist says 80 percent of the time they do absolutely nothing.
“As a group, they always look busy. But as individuals, only a few of them actually spend their time digging,” said Brian Forschler, a researcher with the UGA College of Agricultural and Environmental Sciences.
To control a pest, you first have to know how if operates: its likes and dislikes, what it eats, where it lives, its enemies, etc. Over the years, researchers have made great strides into understanding termite behavior, said Forschler who has studied termites for more than 20 years.
“In the late 1800s to early 1900s they were called white ants. In the 1920s, scientists placed them in a special order (Isoptera) apart from ants. In 2007 they were identified as social cockroaches and classified in the order Blattodea that contains roaches,” Forschler said. “So you see, science isn’t written in stone. It’s constantly being questioned.”
Termites feed on bait in a bait station Image credit: Brian Forschler.
Forschler collects termites in wooden bait traps, takes them back to his Athens laboratory and watches them in action.
“We put sections of 4-inch PVC pipe in the ground, and fill (them) with wooden sandwiches. The problem is figuring out what happens while we aren’t there – we are just getting a snapshot view of their lives,” he said.
Over the years, Forschler has tracked termite colonies, collected termites, dyed them blue or red and released them to track their movement. And he’s created artificial termite families to see how they interact outside their home nests.
In one study, his then graduate student Jeff Whittman placed six groups of termites in tiny arenas and video taped their behavior for seven days.
“They are simple creatures. They did about 10 things. (They) stood around, moved, chewed, tunneled, cleaned other termites and defecated,” he said. “They’re like cows and other animals that feed on cellulose. They spend time throwing-up and chewing their cud.”
Termites forage for food for themselves and take food from other termites, but they never share their cud, he said.
The UGA research team found termites to be very clean animals.
“We consistently saw them clean each other. A termite doesn’t clean itself, except for its antenna. They depend on their brothers and sisters to clean them,” he said.
Adult termites (the king and queen) can reportedly live for 20 years, and Forschler has termites in his collection that are over 14 years old.
“I have some in my lab that are 13 to 14 years old from logs in Georgia, and they were likely 4 years old when we collected them. A number of different types of social insects live that long. It’s not unusual,” he said.
Forschler’s research has also revealed that termites are not random foragers. They tend to use the same access points over and over.
On test sites, used since 2000 on UGA Athens campus, 83 percent of the infestations identified by Forschler’s team entered buildings using expansion joints, 11 percent followed cracks in stone foundations, 4 percent liked areas where wood was in contact with the ground and 2 percent used the weep holes in brick veneer.
Forschler has identified the following termite traits:
The queens lay most of their eggs in the spring.
An average colony contains around 50,000 termites, until they locate a large food resource (like a house, tree stump, or large log). Over the course of a few years that same colony can grow to include hundreds of thousands of termites.
Termites need a humid environment to survive.
Five species of subterranean termites are native to Georgia and one invasive species, the Formosan subterranean termite.
Five of those species swarm and release new adults (kings and queens, called alates) in the late winter and spring (February-May), while one does so in late summer (July-September).
Colonies move all the time and often don’t return to the same spot.
Termites have to swallow soil-applied termiticides to die, not just touch the pesticide.
For more information on termites, see these UGA publications:
The Formosan subterranean termite, Coptotermes formosanus Shiraki, is native to China, was accidentally introduced into the southern U.S., and has since been found in nine southern states. Since 1993, several dozen infestation sites have been found in Georgia.
The Formosan termite is most commonly imported into Georgia by movement of termite-infested railroad crossties. As railroad companies replace crossties, some of the used ones are sold and re-used to build retaining walls and other landscape features. Some of the used crossties are infested with Formosan termites. The termites survive transport and become established in previously un-infested areas when the crossties are installed.Formosan termites remain extremely rare in Georgia, and the presence of railroad crossties in the landscape in no way implies the presence of the termite on one’s property.
Termite Control Technicians and Homeowners Should Learn to Recognize the Formosan Subterranean Termite
It is important that termite control professionals and homeowners be able to differentiate between Formosan subterranean termites and Georgia’s more common native subterranean termites. The primary differences in the two types of termites are in the size, color, and behavior of the swarmers and soldiers.Click on the following link to view a PDF file of the publication Identifying the Formosan Subterranean Termite.
Swarmers
Formosan termite swarmers are larger than native subterranean termite swarmers, measuring about one-half to five-eighths of an inch from tip of head to tip of wings, and the body is caramel-colored (native termite swarmers are black). Formosan termite wings are hairy, while native termite wings are not hairy.In Georgia, Formosan termites swarm at night in May and June and are attracted to lights, whereas native subterranean termites typically swarm during the day and are not attracted to lights.
Soldiers
Formosan termite soldiers exude a white, glue-like secretion from the top of their head when disturbed.Most notably, however, Formosan termite soldiers make up as much as 15-25% of the termites in a colony compared with just 1-3% in a native subterranean termite colony. Formosan termite soldiers are also aggressive, and will often attempt to bite ones finger tip if challenged.
Mud Tubes on Crossties
During swarm season (May and June in Georgia) Formosan termites often build extensive mud tubing on crosstie walls. Unfortunately, these mud tubes are washed away with the first rain.
To Confirm a Formosan Termite Discovery if you are a termite control professional or a homeowner and you think you have found a Formosan termite, we can confirm the termites’ identification. Please collect swarmers and/or soldiers (do not send workers), place them in a small, airtight vial filled with rubbing alcohol, and take the vial to your nearest county extension office, or contact Dr. Daniel R. Suiter on the UGA Griffin Campus at 770-233.6114.
For some 50 years, scientists have tried — but failed — to find a way to use microbes as a means of biological control for destructive subterranean termites.
University of Florida researchers have now discovered why termites have proven to be so disease resistant. Termites use their own feces as nest-building material. The fecal nest promotes the growth of beneficial bacteria, which in turn suppress pathogens — or in plainer words: termite poop works as a natural antibiotic.
Besides improving termite control, the findings could help pave the way for new human antibiotics.
The study, published Wednesday in Proceedings of the Royal Society B, began about nine years ago, when postdoctoral associate Thomas Chouvenc, at the time a student, approached his faculty adviser, Nan-Yao Su, with his wish to study termite-pathogens interactions.
Su said he knew from the reams of scientific literature that biological control attempts in termites hadn’t been successful.
“Instead of saying ‘let’s use fungi to control termites,’ I said, ‘Maybe we could turn the tables around and ask ‘Why has it never worked?’” Su recalled.
Su, the inventor of well-known termite baiting system Sentricon, and Chouvenc are part of UF’s Institute of Food and Agricultural Sciences. Both are based at the UF/IFAS Fort Lauderdale Research and Education Center.
Termites are a $40 billion problem worldwide, and the Formosan subterranean termite accounts for a large portion of the problem.
The research team began to identify and isolate more than 500 strains of bacteria from five termite colonies collected from outdoor sites around Broward County. About 70 percent of the bacteria were shown to be active against a range of bacteria, yeast and fungi.
Researchers then honed in on a specific strain of bacteria called Streptomyces found in the nest material of all five termite colonies.
When they introduced a disease-causing fungus into sterile nest-like environments, they found that the fungus survived and killed the termites. When the Streptomyces bacterium was added to the nest, it protected the termites. When they tested a different bacteria strain against the fungus, it had little effect, leading them to conclude that the Streptomyces bacteria found in the nests may aid the termites by producing beneficial antimicrobial compounds, while feeding on the termite fecal nest.
Chouvenc said it was a time-consuming process but well worth the effort.
“We had to put all of the pieces of the puzzle together and show it was not just an artificial environment that produced this, that it does this in the individual termite nest, as well,” he said.
It is possible the team’s findings may help lead to new microbes that can be used to create new antibiotics for human use, Chouvenc said. Beyond that, he said, they want to tackle questions about how termites evolved to maintain their nests’ health, and whether it’s a stable system or one that’s constantly in flux.
If the termites are able to continually recruit the microbial strains they need to stay disease free, Su said, “then we have to find out how the termites do that.”
The research was funded by royalties Su receives, as well as seed money from UF/IFAS research. The other authors were Caroline Efstathion, a graduate student and employee in Su’s laboratory; and Monica Elliott, a UF/IFAS plant pathology professor also based at the Fort Lauderdale REC.
