February 2023
Who is Tracking Whom

The explosive population of Burmese pythons (Python bivittatus) in South Florida is decimating the ecosystem. Researchers and authorities are developing interesting tactics for tracking and controlling the spread of the estimated tens of thousands that remain in the wild. Luckily, authorities haven’t given up.

One team of researchers are using previously captured pythons to lure and locate other pythons during mating season. Captured adult male and female pythons are implanted with tracking devices and released into an Everglades management area. Pythons form mating aggregations that consist of multiple male suitors lured by a single female that secretes a sex pheromone. The research team believes tracking the snakes during mating and breading season can increase the number of snakes removed, since tracking males will lead the team to sexually reproductive females, and tracking females can lead them to large mating balls. The team is currently tracking eight adult pythons which will provide critical information about behavior, nest and clutch size, hatchlings, and survival rate. Read more here.

Another team hopes to catch large pythons by tracking their pray. Dozens of raccoons and possums were fitted with GPS collars so their locations could be tracked. This was part of a two-part study in which a team of researchers hoped to A) observe what happened when mammals relied on dumpster diving and eating food offered to them by people instead of foraging native seeds and fruit, and B) learn more about pythons if the collared mammals are eaten. The GPS radio collars were equipped with mortality monitors that are triggered by lack of movement. When a collar sends out a mortality signal, but starts moving again, the team knows they “caught” a snake. Out of the 43 mammals collared, six have disappeared and three have been ingested, resulting in the capture of two large female snakes, 66-pounds and 77-pounds, both containing egg follicles. It takes time to track down the snakes, and they are not always successful. However, removing these large female snakes also remove the hundreds of eggs they can lay. Read more here.



 Possum fitted with a GPS radio collar . Credit: Isaac LordPossum fitted with a GPS radio collar that allowed research team to track location and mortality. Credit: Isaac Lord.

An Xray of the captured python revealed a dead possums radio collar. Welleby Veterinary Hospital. USGSAn X-ray of the captured Burmese pythons (Python bivittatus) revealed a dead possums radio collar. Credit: Welleby Veterinary Hospital, USGS.

developing eggs inside female python. Lori Oberhofer. National Park Service. Bugwood.orgDeveloping eggs inside a captured female Burmese python. Credit: Lori Oberhofer, National Park Service, Bugwood.org

Eight Helping Hands

We seem to find ourselves in an unfortunate circular dilemma. When a pest or an invasive is introduced to an area, the first response is typically chemical warfare. This is more and more often resulting in the development of resistance by the target species, death of the many native species, and damage to the environment. Then a different pesticide/herbicide/insecticide is used, which has its own package of problems, solutions, and potential future resistances… lather, rinse, repeat. So, what else can we try? How about spiders!

The tomato leafminer moth (Tuta absoluta) is an invasive agricultural pest in many parts of the world that has developed resistances to chemical insecticides. Left with few other options, researchers explored the use of tropical tent web spiders (Cyrtophora citricola) as a natural predator to combat moth infestations. In the lab, colonies of tent web spiders, varied in body size, were offered different types of prey to determine capture success rate. The spiders were offered small tomato leafminer, flightless fruit flies (Drosophila hydei), and larger black soldier flies (Hermetia illucens). The moths and fruit flies were caught easily, while the large flies were rarely caught. These spiders form large groups, are not cannibalistic, and create large expansive webs, making them an ideal candidate to assist with biocontrol of flying insects compared to more aggressive, solitary spiders. Their interconnecting webs are not only capable of intercepting a high frequency of flying insects, but they also cover an increased surface area which provides a substrate for other spiders, i.e. other predators. This helps to maximize potential pest insect capture within a colony. These spiders are commonly found in overlapping regions of moth infestation.

Additional research is needed to investigate how the presence of a spider colony might affect key pollinators. Researchers also mentioned that these spiders have a natural enemy, a wasp species (Philolema palanichamyi) whose presence can be detrimental to the spider colony. However, if wasp infestations are controlled, these spiders could be an environmentally friendly biocontrol option.

Read the research: Roberts-McEwen et al., 2023

adult Cyrtophora citricola with four egg sacs. Roberts-McEwenAdult tropical tent web spider (Cyrtophora citricola) with four egg sacs. Credit: Roberts-McEwen.

C. citricola colony with visible horizontal web sheets on Opuntia cactus in field. Roberts-McEwenC. citricola colony with visible horizontal web sheets on Opuntia cactus in field. Credit: Roberts-McEwen.

tomato leafminer. Marja van der Straten. NVWA Plant Protection Service. Bugwood.orgTomato leafminer moth (Tuta absoluta). Credit: Marja van der Straten, NVWA Plant Protection Service, Bugwood.org

The Perfect Storm

The exotic pet industry can cause native wildlife populations to decline in areas where species are traded, pushing some populations close to extinctions, as well as introduce new zoonotic pathogens and parasites to humans and animals in areas where exotics are traded. Upwards of a third of animals die before they even arrive to their trade destination. On top of that, the exotic pet trade is also one of the leading drivers of invasive species introduction. It is almost as if the traders and buyers specifically “favor” potentially invasive species. There is actually more truth to this than one might think.

Researchers looked at the life history profiles of different mammals, reptiles, and amphibians to determine population demographics as a prediction tool for future invasives. Life histories can influence the likelihood of trade, introduction, establishment, and spread. They found that species preferred and selected for trade often produced larger numbers of offspring across a longer reproductive lifespan, combined with other relatively ‘fast’ life history traits, such as more frequent litters/eggs/clutches. It is hypothesized that traders prefer these animals because they are more lucrative for industries involving captive breeding. Within traded species, introduced species showed to have a more extreme version of these same life history profiles, suggesting that species most likely to become invasives are at a heightened risk of trade and release.

They found that species with a high invasive potential seemed to be favored within the wildlife trade. The life history traits preferred by traders set them up to be predisposed as successful invasive species. Once traded or sold, they frequently escape and/or are more likely to be deliberately released by owners due to longer-term care requirements. This creates the perfect storm driven by human bias. The life history traits that released species was selected for gives it the upper hand to establish itself in its new environment. Concluding this study, researchers identify multiple species not yet traded or introduced, but with life histories that are indicative of those with high risk of future trade, introduction, and potential invasion.

Read the research: Street et al., 2023

Effects of life history traits on trade frequency and introduction, . street et al
Effects of life history traits on trade frequency and introduction, and traded vs. non-traded species. Mammals (pink), reptiles (blue), and amphibians (gold). Credit: Street et al., 2023

lionfish. Pterois volitans. Rebekah D. Wallace. University of Georgia. Bugwood.org
Argentine black and white tegu. Salvator merianae. Hillsborough County Parks. Recreation and Conservation Department. Bugwood.org
Examples of pets who were part of the exotic trade industry, released by owners, able to successfully establish populations in new ecosystems. Top: Lionfish (Pterois volitans). Credit: Rebekah D. Wallace, University of Georgia, Bugwood.org. Bottom: Argentine black and white tegu (Salvator merianae). Credit: Hillsborough County Parks, Recreation and Conservation Department, Bugwood.org

Are You Growing Any Citrus?

The Asian citrus psyllid (Diaphorina citri) and the citrus greening pathogen (Candidatus liberibacter asiaticus) are threatening citrus in multiple Texas counties, and we need your help to collect samples and monitor the spread to ensure that you and your neighbors are not affected. This pest and pathogen are extremely detrimental to Texas citrus, both economically and agriculturally. The presence of either can greatly affect citrus yield.

TISI is offering FREE diagnostic services! If you suspect your citrus has either the psyllid pest or the Citrus Greening pathogen, or you would like your citrus plants to be part of our screening survey, contact invasives@shsu.edu.

We will send you all the instruction you will need. If you are located within 200 miles of our headquarters, we can collect samples, and/or provide traps and monitoring services ourselves. Not only will we share the results and management strategies (where applicable), but you will become part of a multi-county monitoring survey that is striving to improve the health of Texas citrus!

Also Available: TISI offers educational workshops that highlight information about the Asian citrus psyllid, the pathogen Citrus Greening, and what you need to look out for in your own backyard. If you are interested in this, TISI will provide trapping materials, assist with management strategies, and more. Don’t waste another second. Help us stop the spread!

symptoms of citrus greening. Jeffrey W. Lotz. Florida Department of Agriculture and Consumer Services. Bugwood.org
Symptoms of citrus greening bacterium. Credit: Jeffrey W. Lotz, Florida Department of Agriculture and Consumer Services, bugwood.org

citrus greening
Leaf mottle on grapefruit, a characteristic symptom caused by citrus greening bacterium but also seen on trees infected by Spiroplasma citri. Credit: J.M. Bove.

Aquatic Invasive Species in Commerce Summit

A 3-hour virtual summit on Aquatic Invasive Species in Commerce. It will identify gaps and issues and set the stage to develop strategies and actions to minimize risks posed by aquatic plants and pets in commerce. Expert presenters and panelists will share information on ecommerce, monitoring and inspection, labeling and recordkeeping, regulations and enforcement, voluntary industry standards, and outreach associated with plants and animals in trade.

Date and time: March 8, 2023, 10am-1pm (Pacific). REGISTER.

 aquatic invasive species in commerce
Aquatic Invasive Species in Commerce

Wildlife Forever Releases 2022 National Report on Invasive Species

Wildlife Forever is proud to release the 2022 Clean Drain Dry Initiative annual accomplishment report. Through applied use of media and community outreach, the public awareness campaign generated a staggering 90 million impressions in 2022.

Wildlife Forever launches multi-media outreach campaigns and conducts on-the-ground efforts to slow the spread of invasive species. The Access Enhancement Guidebook is the culmination of years of evaluation, analyzing water accesses, recommending signage, and deploying infrastructure improvements that empower users to prevent the spread of invasive species. The report includes case studies at Shiawassee National Wildlife Refuge and Black Bayou Lake National Wildlife Refuge. FULL PRESS RELEASE.


 wildlife forever 


North American Invasive Species Management Association Training Webinars

This program is designed to provide the education needed for professionals and students who are managing or learning to manage invasive species. The courses include the most current invasive species identification, control, and management techniques, and how to comply with local and federal regulations.

Participants may register and enroll at any time, and will receive a certificate of invasive species management from NAISMA upon completion of the program.

All live webinars are open to the public. Recorded webinars are available to members of NAISMA.

NAISMA 2020 Webinar Schedule:

  • March 15, 1pm - Preventing the Spread of Invasive Species through PlayCleanGo and WorkCleanGo. REGISTER.
  • April 19, 1pm - Ventenata Identification, Impacts, and Management Options. REGISTER.
  • August 16, 1pm - Introduced Plant Pathogens Threatening North American Forests. REGISTER.


Conservation Connections at Jesse H. Jones Park

Join the park staff and volunteers at Jesse H. Jones Park and Nature Center in Humble, TX, for Conservation Connections and Heartwood Volunteer Projects. With dates available throughout March, there will be multiple projects to choose from, anything from planting seeds in the greenhouse, to light landscaping work, to invasive species removal.

Multiple dates to choose from: March 8th, 15th, 22nd, and 29th.
Time: 8:30am- 11:30am

No registration required. Call 281-446-8588 or email JesseJonesPark@pct3.hctx.net for questions.



2023 Spotted Lanternfly Virtual Summit

The 2023 Spotted Lanternfly Virtual Summit is a two-day experience that will discuss current research, geographic distribution, and biocontrol. View the draft agenda (PDF).

Day 1: March 1, 10 am- 5pm

Topics include research updates on SLF phenology and host impact. REGISTER.

Day 2: March 2, 10 am- 5pm

Topics include research updates on SLF impact on crops and forestry. REGISTER


SLF-Summit-2023-v2 copy
SLF Summit 2023

Invasive Spotlight:

African Clawed Frog
(Xenopus laevis)

The African clawed frog (Xenopus laevis) is the largest species of frog found in this unique genus, reaching up to 5 inches in length, Xenopus, and are the only frogs within the genus with clawed toes. They are greenish grey with brown or black mottling, and are fully aquatic. These frogs, as well as all frogs in the family Pipidae, lack teeth and tongues. They rely on their powerful legs and claws to tear food into pieces, which they then shovel into their mouths and down their throat with the assistance of a hyobranchial pump. The African clawed frog lacks true ears. The can sense movements and vibrations in the water through lateral lines that run down the length of the body and underside. They spend almost their entire life cycle in the water. The adult life span is typically 5 to15 years, but African clawed frogs have been recorded to live up to 25 years. Their diet consists of a wide range of animals including fish, crustaceans, insects, and other frogs. They will also scavenge on dead frogs, fish, birds, and small mammals. In the case of a drought, they will burrow into drying mud where they can survive for up to a year without food.

African clawed frogs are a threat to native amphibians and fish since they prey upon tadpoles and fish fry (juvenile fish). The impact of these frogs is not fully understood, but so far they have become an unwelcomed animal in the ecosystems where they are present. In California, these frogs have been associated with the population decline of the western toad (Bufo boreas). In rare instances, African clawed frogs have been observed eating the endangered tidewater goby (Eucyclogobius newberryi) and the endangered three spine stickleback (Gasterosteus aculeatus). These invasive frogs also carry a diverse parasite load and an amphibian fungus called Batrachochytrium dendrobatidis. It is still unclear what kind of threat variables they may pose to nonindigenous ecosystems.

The African clawed frog has been reported in Texas, as well as AZ, CA, CO, FL, KY, MS, NC, VA, and WI. They can be found in natural and artificial ponds or slow-moving creeks. These frogs do not like fast-moving bodies of water. For more information about the African clawed frog, visit the TISI species info page. To report an African clawed frog, please email a picture and location to invasives@shsu.edu.

Xenopus laevis. Near Lilongwe Malawi. Gary Brown 
African clawed frog (Xenopus laevis), Photographed near Lilongwe Malawi. Credit: Gary Brown.
Xenopus laevis. note lateral sensory lines on body. Giuseppe Mazza
African clawed frog swimming. Note the lateral sensory lines along the body. Credit: Giuseppe Mazza.

frog eating fish
African clawed frog eating a fish. Credit: africanrainforestproject.weebly.com

Get Involved Today!!

The Texas Invasive Species Institute (TISI) and The Texas Research Institute for Environmental Studies (TRIES) have many surveys and projects underway. These facilities strive to provide yearly invasive species presence and absence data to the authorities. Pre-screening is one of the first lines of defense in the war against invasives. However, sometimes it is hard to do it alone.

With the aid of the public and citizen scientists, we could cover a much wider area, and gather a more substantial amount of data. When it comes to protecting our environment, there is an opportunity for everyone! Together we can make a difference, one research project at a time.

See how you can get involved by reading the projects listed below or see all the available projects on the Texas Invasives website HERE.

Aquarium Watch: Looking for Prohibited Invasive Aquatic Species

Please help texasinvasives.org and natural habitats by looking for 14 prohibited or invasive aquatic species that might be for sale in your local aquarium store(s). With just one photo you can assist us in finding and documenting which stores are selling prohibited or invasive species. Texasinvasives.org will use this information to contact the appropriate Texas institutions to ensure the appropriate steps are taken for each case.

If you would like more information please email invasives@shsu.edu, and mention you want to assist with our Aquarium Watch.

Air Potato Survey

Help Texas Research Institute for Environmental Studies conduct an air potato survey by actively reporting any infestations seen in your area. The air potato (Dioscorea bulbifera) is a fast growing, high climbing vine. Potato-like tubers are the primary means of reproduction for this vine. They can be as small as a marble or as large as a softball. Native yams are often confused for air potatoes. To avoid this confusion, please refer to the key below:

- Plants rhizomatous; bulbils never produced in leaf axils; petiole base never clasping the stem; Native D. villosa
- Plants tuberous; bulbils produced in leaf axils; petiole base sometimes clasping the stem; Invasive D. bulbifera

For additional information, please refer to the TexasInvasives information page.

If you believe you have identified an air potato vine, please email invasives@shsu.edu and include the following information: an image, an approximate number of vines present, the location (including whether it is on public or private land), and if bulbils are present (the potato-like tubers that emerge from the stem).

Participation opportunities
Participation Opportunities. Credit: KNKleiner, TRIES.

Armorded catfish. Photographer United States Geological Survey
Armored catfish (Hypostomus plecostomus). Credit: United States Geological Survey.

air-potato (Dioscorea bulbifera)2 bulbil. credit Karen Brown
Air-potato (Dioscorea bulbifera), bulbil emerging from leaf axil. Credit: Karen Brown.

More News

CBP Must Hire Crews to Clear Water Hyacinth and Alligator Weed That Grow on Border Wall Grates
Hyacinth (Pontederia crassipes) and alligator weed (Alternanthera philoxeroides) is a problem in and around Cameron County, TX, as the invasive aquatics spread throughout the Rio Grande from Mexico to the United States, clogging U.S. canals that supply water to South Texas towns. borderreport.com

Invasive, Non-Native and Native Species Explained
An article that outlines the district differentiations between native, non-native, and invasive trees and their impact on Texas ecosystems. gilmermirror.com

Invasive Species Week Reminds Outdoorsmen to Battle the Aliens
The Texas Parks and Wildlife Department (TPWD) asks Texans to join the fight against invasive species that negatively impact the state’s natural resources and economy, especially during National Invasive Species Awareness Week (NISAW). sanangelolive.com

Yale Honors Young Scientist Who Was the Subject of a Police Complaint
A young girl was honored at the Yale School of Public Health for her efforts in eradicating invasive spotted lanternflies (Lycorma delicatula) in her hometown with a homemade repellent. The school wanted to honor the girl’s bravery for overcoming another incident of racial profiling exhibited by the police as well as her efforts in fighting back against invasive species. ysph.yale.edu

Scientists Urge Florida Residents to Report Nonnative Lizards as Early Detection Prevents Invasive Spread
The brown basilisk lizard (Basiliscus vittatus) is a non-native species that has been reported in Southern and Central Florida. Experts are collecting information and geographic data to determine the lizard’s invasive potential/risk. phys.org

Simple-To-Use eDNA Test Will Help Track Marine Species
A new method that is fast, cost effective and designed for non-experts that can track and identify native, invasive, and endangered fish, plankton, mollusks, marine mammals, and other organisms in ocean water samples. research.noaa.gov

Alien Plant Species Are Spreading Rapidly in Mountainous Areas, Says New Monitoring Study
Recent research observed the number of invasives in higher elevation region has increased by a global average within the past ten years. They also found the number neophytes have risen in higher elevation areas. phys.org

BOB MAINDELLE: Stillhouse-Belton Zebra Mussel Study Concluded
The conclusion of a multi-year study that was “Assessing the Population Dynamics and Body Condition of Zebra Mussels Within and Between Two Texas Water Bodies with Different Population Trajectories.” inforney.com

Private Forest Landowners in Pennsylvania Want to Use Controlled Fire to Manage Their Woods
Managers of public land have been using prescribed burns to manage tree health and reduce the growth of invasives for decades. A new study indicates that private landowners prefer control burns as a management tool as well. phys.org

Biological Invasions and Invasive Species in Freshwaters: Perception of The General Public
A study aimed to increase awareness of biological invasions by evaluating comprehension, assessing discrimination between invasives and natives, and evaluating conservation. tandfonline.com

Sentinel Pest Network and Invaders of Texas Workshops

Invaders of Texas workshops train volunteers to detect and report invasive species as citizen scientists. Workshops, which are free, are designed to introduce participants to invasive species and the problems they cause, cover aspects of invasive species management, teach identification of local invasive plants, and train participants to report invasive plants using the TX Invaders mobile application. The workshop is 7 hours long (usually on a Saturday, but scheduling is arranged with each individual host group). The workshop satisfies Master Naturalist training requirements.

Sentinel Pest Network workshops serve to increase the awareness and early detection of a set of particularly important invasive species to help prevent their spread into Texas or their further spread within Texas. Participants learn to identify species such as the Emerald Ash Borer, Cactus Moth, Asian Longhorned Beetle, and other pests of regulatory significance, and to report them. The workshop is 3.5 hours long. The workshop satisfies Master Naturalist training requirements.

Upcoming Workshops:

March 9, 2023, 7pm
Invasive Pests near You
In-Person Workshop
Contact: Beth Erwin, thearborlady@gmail.com

April 6, 2023, 10am
North Texas Invasive Species
In-person presentation
Contact: Bobbye Hitzfeld, Bobbye55@outlook.com

CITRUS WORKSHOPS: Stay tuned for upcoming 2023 virtual weekend presentations about Citrus diseases and FREE testing we offer at Texas Invasive Species Institute.