June 2017
Invasive Zebra Mussel's Texas Distribution Expands with Discovery in Canyon Lake and Lake Travis

Zebra mussels (Dreissena polymorpha) have been positively identified for the first time in Lake Travis in the Colorado River Basin in Central Texas, just weeks after biologists confirmed the aquatic invasive species had also spread to the Guadalupe River Basin.

Texas Parks and Wildlife Department (TPWD) and Lower Colorado River Authority (LCRA) biologists confirmed the presence of zebra mussels in Lake Travis June 22 after an observant staff member at a local marina reported the sighting of a single zebra mussel attached to the outboard motor of a moored boat on the lake. On-site, biologists found the mussels attached to other nearby boats and on submerged marina infrastructure. Additionally, they found several size classes of adult and juvenile mussels at two different sites in the lake, indicating the lake is infested with an established, reproducing population.

“This is pretty disheartening for us and our many partners,” said Monica McGarrity, TPWD Aquatic Invasive Species team lead. “But we are very grateful to the marina staff for reporting the sighting, our partners at Texas Invasives for relaying the report to us, and the LCRA for participating in a rapid response to investigate the report.”

Brian Van Zee, Inland Fisheries regional director, said the next step after discovering a new infestation is to educate the public and local marinas to help prevent the zebra mussels from spreading further to nearby lakes. Remember, in Texas, it is unlawful to possess or transport zebra mussels, dead or alive. Boaters are required to drain all water from their boat and onboard receptacles before leaving or approaching a body of fresh water in order to prevent the transfer of zebra mussels. The requirement to drain applies to all types and sizes of boats whether powered or not: personal watercraft, sailboats, kayaks/canoes or any other vessel used on public waters.

More information about zebra mussels can be found online.

Marinas should contact TPWD at 512-389-4848 for assistance if zebra mussels are found on incoming boats—or for coordination when boats are leaving marinas on infested lakes.

If you believe you have found zebra mussels in a water body that doesn't have a record of their presence, please contact TPWD at the number above or report your observation here.

Mansfield dam and Lake Travis
Mansfield Dam and Lake Travis. Credit: LCRA


2017 june 23 zebra mussel status map

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Workshop On Invasive Species Curriculum for High School Teachers

Texasinvasives.org has developed a high school curriculum on invasive species that can be used in environmental science classes. It is designed to introduce students to invasive species and train them as Invaders of Texas citizen scientists. To introduce teachers to the new curriculum, a workshop will be held at the Lady Bird Johnson Wildflower Center, 9:00 am - 4:00 pm on July 11. Learn to transform high school students into citizen scientists as they collect data on local invasive plant species. The lessons will satisfy the TEKS 11-12 grade Environmental Science Section 112.37 (Environmental/Systems). CEU and ES credits are available. Space is limited and registration is required. Registration is $25. Lunch is included!

Register here.

Invaders of Texas citizen science training at Jacksonville High School in 2015, provided by Mike Murphrey, TAMFS. Credit: Laura Cook

Texasinvasives.org Receives Needed Funding from TPWD

For the past several years, the major funding for Texasinvasives.org has generously come from USDA-APHIS (Animal and Plant Health Inspection Service). Things looked grim for Texasinvasives.org for 2017-2018, however, as funding from USDA-APHIS was not renewed. Recognizing the importance of the Texasinvasives.org program and its Invaders of Texas citizen science program (note its role in the discovery of zebra mussels in Lake Travis as covered above), Texas Parks and Wildlife Department was able to provide about $51,500 in funding for the period. We deeply and sincerely appreciate their support, which goes a long way toward ensuring the program continues next year. Please drop a line to TPWD thanking them for their support (choose one of the "Invasive species" topics in the drop-down subject menu). We are also working with the Texas Invasive Plant and Pest Council, the umbrella organization of Texasinvasives.org, to explore sustained support to reduce the risk of losing this important program in the future. If you would like to donate to the program, please contact invaders@texasinvasives.org. Coming soon: "donate" buttons in the iWire and on the Texasinvasives.org website.

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Texas Parks and Wildlife's New "Don't Dump Your Tank" Campaign

“Don’t Let Your Pets Become Pests. Never Dump Your Tank into the Wild” is the key message in a new online ad campaign launched by Texas Parks and Wildlife Dept. on June 19, 2017. The campaign is designed to capture the attention of aquarium enthusiasts and direct them to a new landing page to learn the importance of keeping aquarium fish, animals or plants out of natural bodies of water and how to responsibly dispose of unwanted fish in order to prevent the next invasive species.

Funded by the TPWD’s Coastal Fisheries Division, the ads will appear on Facebook, Google Adwords and aquarium-related websites, and target aquarium owners living in larger cities along the Texas coast. The visuals are light-hearted, colorful illustrations that are designed to soften a sensitive topic for those aquarium owners who have no alternative to setting their fish free—other than euthanasia, which is explained on the landing page. TPWD believes that if people were aware of the devastating consequences that introducing possible new invasive species into Texas’ waters can have, they would put more effort into finding their pets a new home or feel better about euthanizing their aquarium fish/animals in a humane fashion.

The campaign message will be communicated via the online ads from June through August and in ongoing social media (TPWD twitter accounts @TPWDfish and @TPWDnews, and Facebook page), newsletters, e-banners, and emails. A poster, web graphics and a PDF of how to humanely euthanize a fish will also be used.

TPWD Coastal Fisheries is more than happy to share any of the marketing materials at no charge to organizations who want to help spread the word. The materials are available in a variety of sizes and formats at a dropbox address. If you want to know more or talk about how your organization can use these materials, email Janis Johnson at TPWD.

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Article on Invaders of Texas Program Posted in Earthzine

The article on the Invaders of Texas citizen science program, authored by yours truly for the online magazine IEEE Earthzine, has been posted. Check it out! And be sure to read the other articles in the series, if you haven’t already.


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Invasive Spotlight:
Chinese Privet
(Ligustrum sinense)

After the Spotlight on glossy privet (Ligustrum lucidum) last month, we are covering Chinses privet this month. Chinese privet is an evergreen shrub that is aggressive and troublesome, spreading easily and crowding out native plants. It often forms dense thickets, particularly in bottom-land forests and along fencerows, thus gaining access to forests, fields, and right-of-ways. Being shade tolerant, it can invade forest interiors as well. It colonizes by root sprouts and is spread widely by abundant bird- and other animal-dispersed seeds.

Chinese privet has distinctive spreading branches. It is a "small-leaf" privet, with leaf blades up to 2 inches long. Leaves are opposite with short petioles, ovate to elliptic, usually rounded at the tip, sometimes with a small notch, tapering to the base, and with smooth margins. It produces abundant white, fragrant flowers, about 3/8 inch wide, borne in narrow clusters up to 4 inches long, and appearing from March to May. Its fruit are berrylike, bluish black, 1/4 inch long by 3/16 inch wide, in clusters that bend down the branchlets bearing them, and hanging on into winter.

Chinese privet was introduced into the United States in 1852 as an ornamental.

Follow this link to learn more about the Chinese privet.
LISI shrub
Credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

LISI leaves and fruit
Credit: Karan A. Rawlins, University of Georgia, Bugwood.org

More News

Invasive Bagrada Bug Found in Hays County
The Bagrada bug, Bagrada hilaris, an invasive stink bug that has been slowly spreading through the southwestern U.S. for the past decade, has recently been reported in Hays County. "This bug can cause serious crop damage as well as cause damage to plants in commercial nurseries and home gardens and landscapes," said Molly Keck, AgriLife Extension entomologist and integrated pest management specialist, Bexar County. Read more at ipmsouth.com.

Video Shows Invasive Lionfish Feasting On New Caribbean Fish Species
Researchers have reported the first observed case of lionfish (Pterois volitans) preying upon a fish species that had not yet been named. Their results may indicate an uncertain future for other undiscovered fish found in the largely unexplored deep-ocean coral reefs. [Lionfish are also found at depth off the coast of Texas, and thus are likely to be causing the same problems here.] Learn more at sciencedaily.com.

New National Pest Alert for Palmer Amaranth Released
A new National Pest Alert for Palmer Amaranth (Amaranthus palmeri) has been released. This pest alert has been approved by the national leadership of USDA NRCS to address the recent problems with Palmer Amaranth seed inclusion in wildflower and pollinator seed mixes. Ultimately, decisions must be made at the local level to address the issue of Palmer amaranth in pollinator habitats, field edges and conservation plantings. Obtain the alert (pdf format) here.

New Way to Detect Palmer Amaranth in Contaminated Seedlots
Some seed mixtures planted on Conservation Reserve Program acres have been contaminated with Palmer amaranth (Amaranthus palmeri), an aggressive weed. Seed producers must choose between time-consuming or expensive options to certify that their products are free of Palmer amaranth. A new assay can quickly detect Palmer amaranth in mixed seed lots at a comparatively low cost. Learn more at sciencedaily.com.

Islands and Coastal Regions Are Worldwide Hotspots for Alien Plants and Animals
The distribution of established alien species in different regions of the world varies significantly. Until now, scientists were uncertain about where the global hotspots for established alien species are located. Most alien species can be found on islands and coastal regions. Learn more at sciencedaily.com.

Predicting How Heterogeneous Environments Shape Invader Impacts
As a nitrogen-fixing leguminaceous tree, Acacia longifolia, which is native to Australia, adds nitrogen to the soil around it. It thereby affects nitrogen cycling in its community, which can be important in landscapes it invades. Using A. longifolia in typically nitrogen-poor dune habitat as a case study, researchers developed a model that incorporated the interaction among various environmental factors to predict the invader's impact on a native species. Learn more at sciencedaily.com and at the original article.

Predicting the Outcomes of Using Biocontrol Agents
Researchers using a particular type of model show that when pesticides and intentional fires fail to eradicate an invasive plant species, declaring biological war may be the best option. "This individual-based model is used for a lot of ecological research but this is the first time it was used to model the long-term effects of [an insect biocontrol agent on] an invasive species." Read more at sciencedaily.com.


If you would like to highlight a successful invasive species project or nominate a special person to be highlighted in an upcoming iWire, please send the details to iwire@texasinvasives.org.

Sentinel Pest Network and Invaders of Texas Species Workshops

Invaders of Texas workshops train volunteers to become citizen scientists to detect and report invasive species. Workshops, which are free, include information on the Sentinel Pest Network, which serves to increase the awareness and early detection of the Emerald Ash Borer, Cactus Moth, Asian Longhorned Beetle, and other pests of regulatory significance.

Workshops are tailored to meet the interests of your volunteer group, and supplementary session examples include an introduction to the TX Invaders mobile application and the Eradicator Calculator, a feature on Texasinvasives.org designed to help organize and track volunteer-based eradication efforts.

Upcoming Workshops:

Saturday, July 22, 2017
Location: Houston Advanced Research Center Training Facility (The Woodlands, TX)
Contact: Karl Mueller

Saturday, July 29, 2017
Location: Jesse H. Jones Park & Nature Center (Humble, TX)
Contact: Rose Belzung Holmes

For more information or to register to attend a free workshop, please visit the Workshop Page.