Dallas, Texas The first research of cactus moths in Texas found that despite having a tiny inch-long wingspan, this invasive insect has the ability to significantly harm Texas’ agricultural and ecological systems.
Four native species of prickly pear cactus and the species that depend on them pose a major health danger from the moth, according to researchers with The University of Texas at Austin’s Invasive Species Project based at Brackenridge Field Laboratory in Austin.
According to UT Austin doctoral student researcher Colin Morrison, “cactus is a vitally essential element of the landscape.
Cactus provide food and shelter for a wide variety of species in Texas, Mexico, and the Southwest of the United States. Additionally, it is a staple crop for millions of people.
The research, which was just published in the journal Ecological Entomology, examined four native prickly pear species, including one that is used to gather nopales, the prepared cactus pads used in Latin American cooking. Studies revealed that there were hardly any changes in nutritional value between the various kinds and that the cactus moth will consume all four varieties of prickly pears.
Additionally, the cactus’ natural chemical and physical defenses were out to be ineffective against the moth.
We considered the cacti’s hardiness and nutritional value,” Morrison added. ” It is very likely that the invasive cactus moth will be able to thrive, perform, and grow on each of these species. We find this worrying since everywhere we look, it’s pretty much just cactus country.
About 30 years ago, the cactus moth made an island hop from the Caribbean to Florida. The invasive species research team at UT Austin began preparing for its arrival as soon as it began to move toward Texas by researching its natural enemies in Argentina with partner Patricia Folgarait. Florida Entomologist recently published that research. When infestations started to occur along the Texas Gulf Coast in late 2017, experts believe the moth first appeared in Texas. Understanding the likelihood of the moth’s range continuing to grow throughout the state and into Mexico was one of the research’s main objectives.
If nothing is done, these moths will keep growing and, at some point, it won’t be feasible to stop them, according to Morrison.
The cactus moth is not thought to be controlled by natural predators in Texas. Researchers from the U.S. Department of Agriculture have looked into the possibility of using parasitic South American wasps—which feed on cactus moths—to manage cactus moth numbers. However, the moth infestation decimated Florida’s cactus populations prior to the wasp’s field trials being authorized by licenses based on adequate study.
Lawrence Gilbert, Nathan Jones, Colin Morrison, and Robert Plowes all contributed to the study. The Texas Ecolabs program, the Lee and Ramona Bass Foundation, and a UT System-CONACYT ConTex grant all contributed funding to the project.
How did the cactus moth first appear?
In 1925, Australia welcomed the cactus moth from Argentina as a biological defense against the prickly pear cactus. The unique caterpillar Laetilia coccidivora feeds on the eggs and young of scale insects and is a predator.
Where did the cactus moth originate?
NOTE: It is unknown if this pest spreads in or on firewood. The Gallery of Pests simply features it there for informational purposes.
The Cactoblastiscactorum cactus moth is indigenous to northern Argentina, as well as portions of Peru and Paraguay. In the 1960s, it was introduced to the Caribbean islands to manage a number of (native) prickly pear cactus species (Opuntia) (Simonson 2005).
However, the moth was anticipated to have reached Texas by 2007 in the absence of a USDA-led slow-the-spread campaign (see below) (Enkerlin at Entomological Society Symposium, 2010).
Most species of prickly pear cacti (genus Opuntia) can be killed by the cactus moth, especially those with flat pads. The cactus moth has significantly harmed Florida’s six species of delicate prickly pears, three of which are on the state’s endangered or threatened species list (Garrett, 2004). Small people are more at risk of dying from these attacks, which have affected up to 75% of the prickly pear cacti in some areas (Johnson and Stiling 1998, Baker and Stiling 2009).
There is a wide variety of pollinators supported by these cacti. Numerous wildlife species, such as deer, javelina (peccaries), Texas and desert tortoises, and spiny iguanas, rely on them for a consistent and nutrient-rich food source. Packrats, which are devoured by raptors, coyotes, and snakes, as well as breeding birds like the cactus wren and curve-billed thrasher, find shelter under prickly pears. The cacti serve as nursing plants for the seedlings of other desert plants. The highly erodible soils are kept in place by the root systems of the prickly pears (Simonson 2005).
Mexico will be most affected economically by the loss of prickly pear cacti because prickly pears are a source of food for both people and cattle there. Both the tunas (the fruits) and the pads (the pads) of prickly pears are grown (nopales). In the bush, people also gather fruits and pads.
Natural deep-red dye made from the cochineal beetle (Dactylopius coccus), which feeds on prickly pear cacti, is another linked economic crop. Production of cochineal dye is a prominent agricultural crop in Mexico (Simonson 2005). Some people believe that using the color in foods and cosmetics is preferable because it is a natural substance (http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/Cochineal/index.html).
Potential economic losses in the US would be less. Losses could include decreased income from authorized hunting opportunities, depending on what species, if any, move into regions where prickly pear cactus were previously common. In South Texas, ranch land leased for hunting is paid a greater fee than ranch land leased for cow production (Garrett 2004). The widespread demise of prickly pear cacti would likely also have a negative impact on ecotourism in the Southwest.
The program was a joint U.S.-Mexican initiative for a number of years, organized by a SAGARPA/USDA agreement and carried out by the North American Plant Protection Organization (NAPPO). Through this system, Mexico even sent money and staff to help the United States monitor and control moth populations, such as in Louisiana.
Other participants in the study included the Gainesville quarantine laboratory of the Florida Department of Agriculture’s Department of Plant Industry, which houses the facility where cactus moths are raised for various purposes.
studies to enhance the bait utilized in traps, the release of sterile males, and now host specificity testing for biocontrol. A volunteer network run by Mississippi State University was in charge of keeping an eye out for cactus moths on federal, state, and private property along the Gulf Coast.
The USDA program never received enough funding. Never did Congress appropriate money. Over many years, Mexico gave at least $1.4 million. As previously mentioned, the U.S. Geological Survey (Department of Interior), Mississippi State University, and the Florida Department of Agriculture and Consumer Services all contributed to the detection and management of cactus moths.
The program now focuses on biocontrol. Once the cactus moth reaches the arid parts of Texas and the Southwest, where cacti are common, biocontrol is thought to be the only practical control method.
In order to prevent the spread of the cactus moth, APHIS modified its regulations in 2009 to forbid the movement of Opuntia cactus nursery stock from affected states in the Southeast (Federal Register Vol. 74 No. 108 [June 8, 2009], pp. 27071-27076). However, a rule to restrict the importation of prickly pear cacti in 2011 (USDA APHIS 2011) in order to stop further introductions of the moth was never finalized.
Sources
2009; Baker, A. J.; Stiling, P. contrasting the impacts of two species of Florida Opuntia on the foreign cactus-feeding moth Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) and the native Melitara prodenialis (Walker) (Lepidoptera: Pyralidae). 11: 619–624 in Biol. Invasions.
L. Garrett (2004). White Paper: Economic Impact from Cactoblastis cactorum Spread in the United States, USDA APHIS PPQ CPHST.
When was Texas first exposed to the cactus moth?
It was discovered for the first time in Texas in 2018 (Brazoria County), and it is currently found in a number of counties. Because the adults can fly up to 16 miles away and because uninformed people are bringing infected cactus, experts anticipate the moth’s spread through Texas to continue. This is why news coverage and public awareness campaigns are so crucial! The cactus moth is utilized as a biological control agent in regions where Opuntia cacti are invasive because it is so effective at eradicating Opuntia cacti species. Therefore, the native Opuntia cactus population and the ecology it supports are seriously at risk from the cactus moth. The cactus serves as a source of food and refuge for native Lepidoptera, including the endangered Schaus swallowail (Papilio aristodemus ponceanus), birds, reptiles, and other insects. The environment in the area may suffer if the native cactus are decimated and die.
Why was Australia’s cactus moth imported there?
To control various species of North and South American Opuntia, Cactoblastis cactorum, a native of South America, was brought from Argentina to Australia in 1925. The campaign was a resounding success. For the same reason, the cactus moth was later imported to Hawaii, India, South Africa, and a few Caribbean islands. Early in 2009, the cactus moth was discovered and swiftly eliminated in Mujeres, Mexico, which is located about 10 miles off the coast of Cancun (LSU 2009).
Along the Atlantic and Gulf coasts of the United States, the moth’s range is still growing. It is currently found as far west as Louisiana and as far north as Charleston, South Carolina (LSU 2009). Although interior spread is happening, cactoblastis cactorum expands more fast along the beaches. The Florida Department of Agriculture and Consumer Services discovered the moth in Loxahatchee, Palm County, Florida in June 1992, 24 kilometers inland from the Atlantic Ocean. In Putnam County, Florida’s Ordway-Swisher Biological Station, Cactoblastis cactorum was discovered in 2011. (C.W. Miller).