SOUTH TEXAS WILDLIFE

J. R. THOMASSON

A publication of the Caesar Kleberg Wildlife Research Institute Spring 2018 at Texas A&M University-Kingsville Volume 22, No. 1

the effects of habitat fragmentation. Genetic methods are ideal because ecological disturbances that affect multiple generations are reflected in patterns of genetic diversity. Genetic diversity is essential for a population to avoid the effects of inbreeding, limit susceptibility to disease, and adapt to environmental change. We compared genetic differen- tiation and diversity from bobcats sampled in fragmented areas to bobcats sampled in contiguous rangeland habitats. Bobcats often defecate on roads or trails as a means of scent-marking and communica- tion to other cats. DNA extracted from the scats is an efficient way to © Larry Ditto study bobcat populations. We used DNA extracted from bobcat scat to BOBCATS OF THE farming have left only small patches genetically confirm 68 individuals at BORDERLANDS of wildlife habitat scattered across sampling sites within the Lower Rio the landscape. This fragmentation of Grande Valley. by Dan Taylor, Randy DeYoung, habitat is an issue of concern for the Our genetic data revealed sig- and Michael Tewes future persistence of native wildlife nificant evidence for restricted in this unique region. movement and dispersal of bob- Some of the highest rates of Bobcats are among the many cats in fragmented habitat patches human population growth and land- species of wildlife native to the use changes in the U.S. are cur- Lower Rio Grande Valley. Bobcats This Issue rently taking place in the Lower are capable of living in small habitat Bobcats and Genetics...... 1 Rio Grande Valley of South Texas. patches within urban landscapes, Urbanization and expansion of and their movements through the By The Numbers...... 2 fragmented areas can be indicative CKWRI News...... 2 of the effects of fragmentation on Editor’s Note: Mr. Dan Taylor is a graduate student Did You Know?...... 3 at CKWRI/Texas A&M University-Kingsville; other species. Dr. Randy DeYoung is a research scientist at the As part of a collaboration with Managing Tanglehead...... 3 CKWRI and associate professor at Texas A&M University-Kingsville; Dr. Michael Tewes holds the Dr. Terry Blankenship of the Rob and What Do They Eat?...... 4 Frank Daniel Yturria Endowed Chair for Wild Cat Studies at the CKWRI and is a Regents Professor Bessie Welder Wildlife Foundation, at Texas A&M University-Kingsville. we used genetic monitoring to assess Advisory Board...... 4 1 generation in urban areas wildlife populations because of their migrated from range- wide range, mobility, and adaptable lands, whereas about 29% generalist diet. Habitat fragmenta- of bobcats per generation tion that affects bobcats will likely in rangelands migrated affect other species of wildlife that from urban areas. This are less adaptable in responding evidence for directional to landscape changes, such as the migration from urban endangered ocelot. ~ areas to rangelands raises concern for diseases such as those resulting from feline leukemia virus and CKWRI NEWS feline immunodeficiency virus that could be spread- New Advisory Board Member ing from urban areas that We are excited to announce have higher prevalences CKWRI’s new advisory board of these diseases to range- member Jeff Hildebrand. He is land populations. executive chairman and founder of Monitoring connec- Hilcorp Energy Company, an inde- tivity of habitat corridors pendent oil and will be important for the gas explora- long-term conservation tion and pro- of wildlife in the region. duction com- Individual bobcats sampled within the heavily altered landscape of the Lower Rio Grande Valley of South Texas. Habitat patches that can pany located in be used as stepping-stones Houston, TX. or travel corridors to more Hilcorp has compared to contiguous rangeland. secure habitats should be protected been named In fragmented areas, bobcats sam- or established to ensure sufficient to FORTUNE pled within 15 miles of each other dispersal from the bobcat population Magazine’s Mr. Jeff Hildebrand is were genetically similar. Bobcats of the Lower Rio Grande Valley to 100 best CKWRI’s new advi- sampled in rangelands showed no favorable ranchland habitat. workplaces in sory board member. relationship between genetic similar- Bobcats should continue to be America for ity and geographic distance. Bobcat used as an indicator species for the the past 5 years. Prior to found- dispersal appears restricted in the effects of habitat fragmentation on ing Hilcorp in 1989, Jeff was with fragmented areas, and bobcats may Exxon, the Dan A. Hughes Com- have a difficult time avoiding mating The proportion of individual bobcats per pany, and American Energy Capital with close relatives. generation that migrated from or stayed Corporation. He earned a BS in within their respective rangeland or urban We also conducted analyses to populations, estimated from genetic data geology in 1981 and a MS in petro- determine migration rates among collected in 2016–2017.­ leum engineering in 1985, both from fragments and rangelands. Estimates The University of Texas at Austin. indicated that bobcats in the frag- Bobcat Population Dispersal Mr. Hildebrand actively par- mented areas are likely to remain FROM FROM ticipates in the community, serving within or disperse to rangeland, but Rangeland Urban on the boards of Central Houston, dispersal rarely occurred into the Inc., Houston Livestock Show and fragmented areas from the range- TO Rangeland 71.4% 28.6% Rodeo, Houston Police Foundation, land. Only about 3% of bobcats per TO Urban 3.3% 96.7% Rice University’s Baker Institute for Public Policy, The University of By The Numbers Texas Systems Board of Regents, The University of Texas Investment 88 average weight in pounds (40 kg) of an adult female Management Company, and the pronghorn in Texas (The Mammals of Texas, W.B. Davis and D.J. Schmidly, University Lands Advisory Board. Texas Parks and Wildlife Press) 22–23 incubation period in days needed for scaled quail eggs to hatch (Chapter 5: Scaled Quail Ecology and Life History by N.J. Silvy et al. In Texas Visit our web page at Quails Ecology and Management, L.A. Brennan editor, Texas A&M University Press) http://www.ckwri.tamuk.edu

2 TCTWS Meeting Highlights Research by the CKWRI was on Did You Know? display at the 54th meeting of the The ear of an eastern cottontail is 50–60% as long as its hind foot. Texas Chapter of The Wildlife Soci- (The Mammals of Texas, W.B. Davis and D.J. Schmidly, Texas Parks and Wildlife Press) ety (TCTWS) held February 9–11 in Dallas, TX. Twenty-six of 87 The common moorhen makes 4 types of nest structures: false (30%) oral presentations and 29 of nests, egg nests, brood nests, and platforms. (Chapter 10: Common Moorhen by E.D. Greij. In Migratory Shore and Upland Game Bird Management in North America, T.C. 87 (33%) poster presentations were Tacha and C.E. Braun editors, Allen Press) by CKWRI researchers, graduate students, and undergraduate students Curriculum into the Sixth and expanded at an unprecedented rate working with CKWRI researchers. Seventh Grade Classroom” was on native rangelands, particularly in Gael Sanchez and Janel Ortiz coauthored by CKWRI scientists the sand sheet region of South Texas. placed 1st and 3rd in the Clarence Drs. April Torres Conkey and This region is characterized by beef Cottam Award competition. Gael’s Leonard Brennan, and Drs. production and wildlife enterprises, La Vonne Fedynich and Marybeth and the increased dominance of tan- Green (TAMUK). glehead has concerned landowners Receiving the Outstanding and scientists because of the changes Popular Article Award was Dr. it is causing to the ecosystem. Michael Tewes for “Clinging to Research has shown invasive grasses can reduce plant community diversity and decrease the abundance of birds and insects. Tanglehead has also earned itself a new reputation for being poor in palatability and is © TCTWS avoided by cattle when it matures. Gael Sanchez receiving the 1st place CKWRI researchers have been Clarence Cottam Award from Corey Mason, outgoing president of the TCTWS. studying tanglehead for a number of years to gain insights on how to counteract its expansion. They presentation “Analysis of Allelic © TCTWS found that seeds from the plant Variation in Prion Protein Gene of Dr. Michael Tewes receiving the Outstanding decrease in viability over time within Popular Article Award from Corey Mason, Texas Mule Deer” was coauthored outgoing president of the TCTWS. the soil, prompting recommenda- by CKWRI scientists Drs. Randy tions to reduce soil disturbance, DeYoung, Damon Williford, David thereby preventing the addition of Hewitt, Timothy Fulbright, and Survival in the Borderlands,” which seeds into the seedbank. Prescribed Humberto Perotto-Baldiviseo, was published in the September/ burning in fall months will destroy and Dr. Louis Harveson (Sul October 2017 issue of The Wildlife seeds on plants and the ground sur- Ross University) and Shawn Gray Professional­—a publication of The face, preventing them from making (TPWD). Janel’s presentation Wildlife Society. ~ their way into the soil. However, “Taking Them Under My Wing: after burning, seedlings will rapidly Integrating Wild Bird Conservation establish themselves, at times cover- TANGLEHEAD MANAGEMENT ing the soil surface at one seedling WITH CATTLE AND BURNING by Chase H. Walther

Tanglehead is a native bunch grass once named a “decreaser” and “good forage grass” for cattle. It has

Editor’s Note: Mr. Chase Walther is a graduate student at CKWRI/Texas A&M University- © TCTWS Kingsville whose advisor and mentor is Dr. J. © J. Alfonso Ortega-S. Alfonso Ortega-Santos, research scientist at Janel Ortiz receiving the 3rd place Clarence CKWRI and professor within the Department of Prescribed burning was conducted in Cottam Award from Corey Mason, outgoing Animal, Rangeland, and Wildlife Sciences at Texas tanglehead pastures, which had fine fuel president of the TCTWS. A&M University-Kingsville. loads of over 5,000 pounds per acre. 3 per square inch. This facilitates the Advisory Board invasion instead of controlling it. The Advisory Board of the Caesar Kleberg Wildlife Research Institute provides leadership in all To confront the issue, a new study aspects of our work. We are indebted to them for their commitment to CKWRI and its mission. is being conducted using cattle to Chad Auler David W. Killam James A. McAllen counteract the explosive regrowth Gus T. Canales (Chairman) Ellen B. Randall T. Dan Friedkin Mason D. King Barry Coates Roberts after a fire. Henry R. Hamman Chris C. Kleberg Stuart W. Stedman Tanglehead is highly palatable Jeff Hildebrand Tio Kleberg Ben F. Vaughan, III George C. “Tim” Hixon C. Berdon Lawrence Bryan Wagner in its early growth stages after a Karen Hunke Tim Leach Charles A. Williams fire. We are using this characteristic A. C. “Dick” Jones, IV Kenneth E. Leonard in conjunction with patch-burning to develop a technique that would The study is ongoing, but the reduce tanglehead dominance. results gathered thus far are promis- Patch-burning concentrates ing. Vegetation sampling shows that cattle on the burned areas because nearly twice as many native plant they prefer the new growth. This species can be found in burned areas maximizes grazing pressure on the compared to unburned areas. Data emerging tanglehead seedlings, from GPS collars placed on cattle preventing them from maturing and show that cattle are 4.5 times more producing seed while allowing other likely to graze tanglehead after burn- plant species to establish themselves. © J. Alfonso Ortega-S. ing than before burning. Cattle also Cattle also benefit from the high GPS-collared cattle were placed in mature used 8 times more of the available tanglehead pastures a month before the nutrient content produced after the burns to assess their movements and use. forage in the burned areas compared burn and still have enough dry matter to the unburned areas. available in the rest of the pasture GPS monitoring and vegetation to fulfill their daily requirements. selective when grazing, thereby sampling will allow us to get an Because all their nutritional require- avoiding forbs and other native accurate picture of cattle movements ments are being met, cattle can be grasses to focus on tanglehead. and tanglehead response to burning and grazing as the plant community develops. The next step in the study What Do They Eat? is to burn more patches, creating a Pipevine swallowtail caterpillars only forage on the leaves of plants diversity of growth stages available found in the Pipevine Family. (http://whatdocaterpillarseat.com/) to cattle and wildlife while reducing the dominance of tanglehead. ~ Belted kingfishers mainly eat fish, but will take crustaceans, snails, amphibians, and small birds. (Handbook of Birds of the World, Vol. 6, del Hoyo et Consider giving a tax-deductible al., Lynx Edicions) donation to CKWRI

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Editor: Alan Fedynich, Ph.D. SOUTH TEXAS WILDLIFE is printed on recycled paper

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