Season 5, episode 12.
From the Northern reaches of the Llano Estacado in Eastern New Mexico to the Big Bend Borderlands of Texas, this is Nature Notes.
Zombies and vampires are popular in the movies these days, but there’s a bloodsucking insect that’s really a lot scarier than anything at the movies Ever hear of kissing bugs?.
From Marfa Public Radio, in cooperation with the Sibley Nature Center in Midland, Texas, this is Nature Notes. Hello, I’m Dallas Baxter.
Cone nose bugs, kissing bugs and assassin bugs are all common names for triatomines, an inch-long black insect with a long "nose" and wings that fold over a flattened body that is wider than the wings. This flattened body usually has an alternating pattern of dark and bright yellow or red. There are 10 species in the United States, of which 8 are found in Texas. Triatomines are bloodsuckers, and are often found in some bird nests, kangaroo rat burrows, and packrat nests. They are carriers of Chagas Disease, common in South and Central America and now spreading north, with reports of the disease in the southern half of the U.S. from coast to coast.
Kissing bugs are found in the southern Llano Estacado, the Edwards Plateau, and the Trans-Pecos. When populations become too large for one area, the adults disperse. They are extremely sensitive to carbon dioxide, being able to detect 75 parts per million. They generally feed at night, hiding in crevices by day. A kissing bug imbibes more than its body weight of blood in less than 30 minutes. Since blood is mostly water, they excrete the water as they feed, often on the host, which in turn, act as aggregation pheromones, attracting more kissing bugs.
Triatomines hide out during the day but hunt for blood at night when the air is cooler and the host is asleep. Heat guides the insects as well as carbon dioxide exhaled by the sleeping victim.
The acute phase of Chagas disease is a mild fever, and then the individual affected develops "achy bones." The next day, the only remaining effect is a sense of tiredness. The symptoms then go into remission, resurfacing many years later, causing gastrointestinal problems and enlarged liver and spleen that can facilitate further problems. It is not often a fatal disease, but can sometimes lead to death.
Charles Darwin came into contact with Triatomines in the early 19th century in Argentina as he explored the area. He wrote about his first encounter in his journal published in 1839.
To prevent kissing bugs from finding sanctuary in your house, don’t leave clothes piled up or have stacks of paper and magazines. Make sure the house is well caulked, including utility line points of entry. Triatomines are often attracted to light, so instead of having a porch light above the door, have a walkway light a dozen feet from the door, and use yellow lights instead of white. Make sure the weather stripping and window screens are in good shape. And avoid having hiding places like piles of firewood or stacks of lumber or bricks in the yard.
Recent evidence indicates that Chagas disease continues to move northward. The disease moves from triatomine to triatomine when in aggregations, and travels with the bugs’ dispersal. Some doctors are now recommending mandatory reporting of Chagas disease in Texas, testing of blood donations and canine testing for Chagas disease antibodies in high risk counties. There is hope that a joint initiative will be developed between the United States and México to combat Chagas disease.
Nature Notes is sponsored by the Dixon Water Foundation and is produced by KRTS Marfa Public Radio in cooperation with the Sibley Nature Center in Midland, Texas. This episode was written by Burr Williams. Visit sibleynaturecenter.org and join Williams' Facebook page where photos are posted daily.