Lots of animals and insects turn to flower nectar not only for a tasty morsel but also for an important energy source. Birds, bees, moths, and butterflies are not the only individuals found fluttering around flowers. Less-recognized nectar consumers such as bats, flies, ants, and some rodents also play a role in pollination. However, some invasive species have been dubbed “nectar thieves” and can impact pollinator foraging behavior.

Argentine ants (Linepithema humile) are an invasive ecological threat in the U.S., especially in the southern states. Adults are 2–3 mm long, slender, shiny, smooth, and light to dark brown. Colonies have multiple queens and can construct supercolonies that easily outnumber and displace native species. Researchers found that two-thirds of bumble bee (Bombus impatiens) interactions at nectar resources involve a direct encounter with Argentine ants. These encounters increase the likelihood of competition.

During a lab study, over 4,000 individual behaviors were observed and recorded from 415 bumble bees from six colonies that were foraging in a shared area. Each colony could approach nectar feeders that either had ants nearby or no ants at all. When a bee encountered a feeder with ants, it triggered a prolonged period of aggression. Once a bee shifted into a fight response, it was both more likely to be bitten by ants and less likely to continue foraging. Although bumble bees can sting without dying (unlike honeybees), they appeared to rely on their mandibles to defend themselves against the ants. Ant heads were often observed on the legs of bees as a result of the bees being bitten and then decapitating the ants in response to the attack.

Observations showed that while bees would risk some bites, they consistently avoided feeders with large numbers of ants. This is likely due to disruptive foraging and costly attack behavior. Additional research is needed to determine how the colony responds when foraging bees return with fewer resources than expected as a result of these encounters. Researchers are interested in whether colonies send out additional foragers or wait until there is a reduced ant presence.

Read the research: Miner and Wilson-Rankin, 2025

SLF Still Moving West

The spotted lanternfly (Lycorma delicatula, SLF) is considered one of the fastest-spreading invasive species in the U.S. Since its introduction to Pennsylvania in 2014, it has quickly spread west and has significant potential for continued expansion. The SLF is currently found in 17 states and has been detected in a total of 20 states. A map based on combined USDA analysis was recently produced to represent the potential geographical habitat suitable for SLF distribution across the U.S. The map indicates that almost all states, either fully or partially, could serve as ideal habitat if SLF introduction occurred. Only North Dakota appears to be spared.

SLF often lay their eggs on tree bark, and the eggs can survive indoors for weeks. Egg masses are well camouflaged, making them difficult to detect. They are gray-brown, mud-like, and hatch in the spring. Nymphs target soft fruit trees and grapevines, causing significant agricultural damage. Egg masses are also commonly found on buildings, camping equipment, picnic tables, trailers, sheds, and other outdoor surfaces.

The spotted lanternfly is now present or has been reported in many of the following states: Connecticut, Delaware, Indiana, Illinois, Iowa, Kentucky, Maryland, Massachusetts, Michigan, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Virginia, and West Virginia. It has been intercepted in California and is currently being surveyed for in multiple states, including Texas.

For more information about SLF: texasinvasive.org
To report SLF: REPORT IT!

Don’t Mess With Texas Citrus

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.

The Asian citrus psyllid (Diaphorina citri) and the Citrus Greening pathogen (Candidatus liberibacter asiaticus) are threatening citrus in multiple Texas counties. By taking samples and monitoring the spread, it is easier 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.

If you are interested in having your citrus trees checked or being part of the survey, please contact invasives@shsu.edu. If you are located within 200 miles of our headquarters, we can collect samples and/or provide traps and monitoring services. Otherwise, we will send you easy step-by-step instructions so you can do it yourself. 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!

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 2025 Webinar Schedule:

• December 17, 1pm CST- Biocontrol Allies: Managing Spotted Lanternfly and Tree-of-Heaven. REGISTER.

Mini-Series Monthly Webinars

Don’t miss an all-new mini-series of webinars exploring the many ways invasive species can impact your local community and its ecosystem. Discover what you can learn—and what actions you can take—to prevent, manage, and respond to these ecological threats.

A new video will be available the first Wednesday of each month until the end of the year. This series is FREE and open to the public. Advance registration is required. All webinars will be recorded and posted to the University of California YouTube channel after each webinar.

December 3, 2025 – How Invasive Pests Are Managed in California
Collaborative efforts are needed to prevent new introductions, limit the spread, and mitigate the impacts of invasive pests in California. Learn what state agencies do to protect the state, from prevention strategies, success stories, current management efforts, and biological control program. Register here.

Join NIASMA for the 2nd annual International Invasive Species and Climate Change Conference (IISCCC) organized by the Regional Invasive Species and Climate Change (RISCC) Management Network. This conference is VIRTUAL and FREE.

December 9-10, 2025

REGISTER HERE.

U.S. Customs and Border Protection (CBP) at the Anzalduas International Bridge in Texas intercepted a vehicle attempting to illegally transport exotic pets from the United States into Mexico. The vehicle was stopped by CBP enforcement officers at the outbound operations port, where it was selected for inspection. A physical inspection revealed 166 live reptiles, spiders, and centipedes in jars and bags concealed within the vehicle. The car was seized and the driver was arrested. The U.S. Fish and Wildlife Service took custody of the reptiles and arthropods. Authorities say that exotic pet smuggling is on the rise and are working to ensure that people who import and export exotic species follow federal requirements.

For a full list of the seized exotic animals and for more information, see the Official Press Release.

Join the Native Prairies Association of Texas (NPAT) for the Maddin Prairie Fall Workdays as they work to support the maintenance of Maddin Prairie. This 1,114-acre preserve in the rolling plains of Mitchell County, Texas, is a refuge for native grasslands and wildlife. The goals for this weekend event include clearing roads for accessibility, restoring habitat, and removing invasive species. No prior experience is needed. Everyone is welcome.

NPAT will provide tools, gloves, and refreshments. Please dress appropriately: long sleeves, long pants, sun protection, closed-toe shoes, and other protective clothing as needed.

Volunteers are welcome to stay for a day or the whole weekend—whatever fits their schedule. Tent camping is available on-site, and additional accommodations are available nearby in Colorado City, Texas.

December 5, 9:00am – December 7, 12:00pm

For registration and more information, Click HERE.

Invasive Spotlight:

Castor Bean
(Ricinus communis)

Castor bean (Ricinus communis) is an annual shrub that grows between 3 and 16 feet (1–5 m) tall. Stems are heavily branched and range in color from red to green to purplish. The large, alternate leaves are palmately shaped with 6–11 lobes, ranging from 4 to 22 inches in size. They can be green to red in color and have toothed edges. Flowers grow in ball-like clusters on a stalk and are apetalous (without petals). The inflorescence consists of a five-parted calyx with branching red stigmas (female flowers) toward the top and yellow anthers (male flowers) near the bottom. The flowers typically bloom between August and November.

Female flowers develop reddish-brown oblong capsules about 1 inch long, covered in dense, sharp spines and containing three seeds each. Seeds are also oblong, varying in size and color from black to copper. Seeds germinate in early spring. Plants become reproductive within six months of growth, bloom from summer through fall, and seeds can remain viable for 2–3 years. Once established, the shrub is fast-growing and can quickly displace native vegetation.

Castor bean contains a highly toxic compound known as ricin. Ricin is a deadly natural poison and can be extremely harmful to humans; consuming just a few seeds can be fatal. All parts of the plant can cause skin irritation, and the pollen can trigger allergic asthma reactions. The plant can also poison local insect populations and introduce ricin into nearby ecosystems.

Castor bean can be found in disturbed areas such as fields, pastures, waste areas, and along roadsides and railways. This plant prefers full sun and well-drained, fertilized, moist soils. It has been reported in the following states: AZ, CA, CT, DC, DE, FL, GA, HI, IL, LA, MA, MI, MO, MS, NC, NH, OH, PA, TN, TX, and VA. In Texas, it has been reported throughout the state except for the Trans-Pecos and Panhandle/High Plains regions.

If you think you have seen a castor bean plant, REPORT IT! to invasives@shsu.edu. Please include a photo, a description, and the location. For more information about the castor bean, visit the TexasInvasives.org species page.

Invasive Plant Spreads After Hill Country Floods; Guadalupe Bass, Native Species Hold Steady
Months after major flooding, authorities have begun a year-long fish recovery and survey to document habitat conditions across Guadalupe, Llano, Nueces, Pedernales, and San Saba rivers. ksat.com

Crop Rotation Delivers Higher Yields, Better Nutrition, And Increased Farm Revenues Across Six Continents, Study Shows
An international study bolstered by over 3000 trial observations drawn from over 700 experiments across 6 continents has shown that the practice of crop rotation provides many benefits over continuous monoculture. phys.org

Can Invasive Plants Increase Tick Exposure Risk? Scientists Reveal a Surprising Link to Human Health
Lone star ticks (Amblyomma americanum) are found to survive longer in areas dominated by cogongrass (Imperata cylindrica), a widely distributed invasive grass. Cogongrass was found to provide ticks with ideal environmental conditions. news.ufl.edu

A New AI-Based Method to Help Prevent Biological Invasions
A group of researchers have developed an AI-driven framework to predict and identify which plant species are the most likely to become invasive before being introduced to a new area. today.uconn.edu

CABI scientists suggest an accidentally introduced parasitoid could save box trees from ecological extinction
A yet-to-be-identified species of parasitic wasp in the genera Eriborus could be used as a biological control for the box tree moth (Cydalima perspectalis) in Europe and North America to save box trees. cabi.org

Introduced Animals Change How Island Plants Spread, Global Study Finds
Invasive animals have a greater impact on plant seed dispersal compared to the reduction of seed dispersal caused because of native species extinction. phys.org

Large Invasive Rodents Carry Disease and Attack Crops Across California Wetlands
Nutria (Myocastor coypus) are large invasive rodents that resemble beavers, muskrats, or 20-pound rats. Once part of the fur trade, they are now problematic and spreading geographically. California authorities are having a hard time making headway. localnewsmatters.org

Spotted Lanternfly May Use 'Toxic Shield' To Fend Off Bird Predators
Several species of bird were less likely to eat spotted lanternflies (Lycorma delicatula) after feeding on the tree of heaven (Ailanthus altissima) suggesting the bug is storing nasty-tasting chemicals from the plant during feeding that is deterring predatory birds. phys.org

The Presence of Reeds on Riverbanks Could Be Beneficial for Fish
The invasive giant reed (Arundo donax) can alter the natural balance of rivers under certain conditions and has been found to provide valuable habitat for fish. ub.edu

Reducing The Risks of Wildlife Corridors
Connecting fragmented habitats using wildlife corridors can improve biodiversity, but they can also pose ecological risks, such as the unintentional spread of wildlife diseases and invasive species. leeds.ac.uk

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.