Conservation Status of the Plains Spotted Skunk, Spilogale putorius interrupta, in Texas, with an Assessment of Genetic Variability in the Species

Robert C. Dowler, Department of Biology at Angelo State University is the corresponding author, robert dot dowler at angelo dot eduIn this report, we present results of research on the conservation status of the plains spotted skunk (Spilogale putorius interrupta) in Texas and an assessment of the genetic variability in populations throughout the range of the species. The conservation status portion of the study included (1) mapping the species’ potential habitat in Texas using maximum entropy modeling (Maxent) with historic museum specimen records, (2) field-based surveying of locations in 10 counties to determine occurrence of the plains spotted skunk, (3) seeking additional occurrence records in Texas through crowd sourcing and citizen scientist approaches (4) using all current (2001 – 2017) occurrences to produce a model of probable geographic distribution in Texas and (5) assessing anthropogenic changes in land use, which may threaten the species’ habitats, by mapping current and forecasted oil and gas development and urbanization within the species’ modeled range. The species distribution model, combined with the land-change assessment, was used to select sites in 10 representative counties for field-based surveys in the hopes of revealing patterns of current distribution. Field surveys were carried out using live traps, enclosed track plates, and camera traps. These methods documented detections of plains spotted skunks (n = 12) in 4 of the 10 sites sampled. All methods of detection were successful, but cameras and live traps out-performed track plates. Crowd-sourced approaches and citizen scientist camera trapping revealed an additional 82 occurrences in the state, 79 of which were since 2009. These recent records were used to produce a species distribution model that provides relative probability of occurrence for the plains spotted skunk in the state. Our land-change mapping revealed potential anthropogenic threats to habitats at 2 of the sites (Katy Prairie and Fort Hood), which also had robust populations of plains spotted skunks based on 25 and 51detections, respectively). For our genetic assessment, samples of tissue from three sources (i.e., field surveys, state agencies throughout the distribution of the eastern spotted skunk, and museum tissue collections) allowed a detailed assessment of the genetic variability in the species (S. putorius) using both microsatellite markers and cytochrome b gene sequence. Our analysis of 119 specimens was able to establish that genetic patterns were consistent with currently accepted taxonomy of the 3 recognized subspecies of S. putorius (S. p. putorius, S. p. ambarvalis, and S. p. interrupta). We also determined that there was no evidence for hybridization with the congener, S. gracilis (western spotted skunk), a species co-occurring with the eastern spotted skunk in parts of Texas. The differentiation between S. p. putorius and S. p. ambarvalis was less pronounced (FST = 0.178; cytochrome b sequence divergence = 1.2%) than between these subspecies and the plains spotted skunk (average FST = 0.278; cytochrome b sequence divergence = 2.9%). Overall, genetic variability (observed heterozygosity = 0.474) in the plains spotted skunk was lower than that seen in common carnivores (striped skunks, raccoons), but slightly higher than some endangered carnivores (black-footed ferret). The heterozygosity levels more closely resemble the levels found within the island spotted skunk (S. gracilis amphiala) from the Channel Islands of California and other vertebrates that have a “threatened” conservation status. Key findings of the study include: 1) the current geographic distribution of the plains spotted skunk in Texas is reduced relative to historic records; 2) the species distribution model based on recorded occurrences since 2001 suggests areas of the state that are in need of further survey efforts; 3) genetic variability of plains spotted skunks is lower than more common carnivores, but higher than some recognized endangered species; 4) the subspecies, S. p. interrupta is a distinct genetic subunit of the eastern spotted skunk; and 5) continued energy development and especially future urbanization in some parts of Texas may affect populations of the plains spotted skunk.Texas Comptroller of Public AccountsBureau of Economic Geolog

Conserving Texas Biodiversity: Status, Trends, and Conservation Planning for Fishes of Greatest Conservation Need

The primary aim of this grant was to work with Texas Parks and Wildlife (TPWD), Texas Advanced Computing Center (University of Texas at Austin), and other relevant collaborators to (1) utilize Fishes of Texas Project (FoTX) data to aid in conservation of Texas fishes, (2) conduct field surveys in areas of limited data and of conservation interest, and (3) further develop the FoTX database and website as a research and management tool. While much of our work was focused on Species of Greatest Conservation Need (SGCN), almost everything we did has been applied to all species, or affects the data for all species in some way. Our efforts here demonstrate the value of reliable and verifiable specimen data to conservation and serve as a baseline upon which to build a conservation program. The FoTX data have taken many years to fully develop, largely funded by State Wildlife Grant funds, and that work will continue to evolve, but this report documents how the data have now been used to develop species distribution models and conservation priority areas that are now the foundation of aquatic resource conservation prioritization and management in Texas. Our data were also used by TPWD staff to update the Texas Natural Diversity Database, which was previously depauperate for fish data, and to develop state and global conservation rankings for fishes using NatureServe’s standard methodology. Using the FoTX data we also developed recommendations for updating TPWD’s SGCN list, which if implemented will inform conservation in Texas for many years. We expanded the scope of FoTX to include a larger geography, into Texas’ neighboring states, thus reducing biases caused by our previous political boundary that lacked a biogeographical basis, and to include many new records from new types of complementary data sources, especially agency databases, that together with the museum specimen data provide a more thorough and unbiased dataset for understanding temporal and spatial trends in fish biogeography in Texas. We also developed and integrated tools into the website such as improved checklists and tools for accessing occurrence data held in digitized documents. One of the features most requested by our data users were native ranges for all Texas fish species, which we recently produced and can be viewed in our mapping tab. These native ranges, when viewed alongside occurrence data, allow users to understand trends in shifting distributions over time. We focused another effort explicitly at understanding range changes through time and have produced dynamic graphs, which when fully implemented will update automatically when the underlying data are changed, depicting latitudinal and longitudinal changes over time and general range size changes through time. In addition to this, we were active in the field collecting fishes, focusing on locations where data are lacking or there were other conservation related reasons for collecting. This effort has largely been in coordination with TPWD staff, who have been heavily involved with many of the activities in this project. The collecting effort has resulted in a large number of new specimens and tissue samples deposited and permanently housed in the University of Texas Biodiversity Collections (Texas Natural History Collections) and represents a model for how long term collections and data archiving and management can be achieved. These data are the newest in FoTX and represent the modern data point upon which conservation actions can be effectively implemented. The funding provided for this project has allowed us to continue to grow and diversify, moving away from focusing solely on improving the data themselves, but also on applying those data in diverse ways that maximize their value for conservation. The project has inspired a Herps of Texas Project (HoTX, currently funded by TPWD) and we agreed to allow use of our database schema and website structure as a template to build their project. Getting that project to a similar state as FoTX should be much faster and require far less funding than has been devoted to FoTX. Any improvements to HoTX could also likely be applied to improve FoTX. Our hope is that other projects, focusing on various taxa (e.g. mussels), continue to follow in our footsteps allowing mutual benefit and eventually query interfaces that allow users to access entire ecological communities.Texas Parks and Wildlife Department through U.S. Fish and Wildlife Service State Wildlife Grant Program, grant TX T-106-1 (CFDA# 15.634)Integrative Biolog

Phylogenetic structure of Holbrookia lacerata (Cope 1880) (Squamata: Phrynosomatidae): one species or two?

Hibbitts, Toby J., Ryberg, Wade A., Harvey, Johanna A., Voelker, Gary, Lawing, A. Michelle, Adams, Connor S., Neuharth, Dalton B., Dittmer, Drew E., Duran, C. Michael, Wolaver, Brad D., Pierre, Jon Paul, Labay, Benjamin J., Laduc, Travis J. (2019): Phylogenetic structure of Holbrookia lacerata (Cope 1880) (Squamata: Phrynosomatidae): one species or two? Zootaxa 4619 (1): 139-154, DOI: 10.11646/zootaxa.4619.1.

Holbrookia subcaudalis

Holbrookia subcaudalis (Axtell 1956) Tamaulipan Spot-tailed Earless Lizard (Fig. 9) Holbrookia lacerata subcaudalis Axtell 1956 Holbrookia subcaudalis Hibbitts et al. 2019 (this study) Holotype. Texas Natural History Collection, University of Texas (TNHC 20000); collected by Ralph W. Axtell on 6 June 1955 in plowed field 4.8 miles east northeast of Bishop, Nueces County, Texas, USA (27º 36’ N; 97º 45’ W) at an elevation of 75 feet. Etymology. The name subcaudalis is derived from the latin word sub which means under or below and cauda which means tail. This refers to the dark spots on the underside of the tail in this species. Distribution. Holbrookia subcaudalis is composed of all populations south of the Balcones Escarpment in Texas and west to the Sierra Madre Oriental in Coahuila, Nuevo Leon, and Tamaulipas, Mexico. They are absent from areas with sandy soils. Diagnosis. Morphological description based on measurements and counts from 45 adults. This is a small, earless lizard with an average of 5 (1 – 10) black spots on the underside of the tail. The average snout-vent length (SVL) is 56 mm (31 – 72), paravertebral and dorsolateral body blotches are often separated. An average of 0.7 (0 – 6) blotches are fused out of an average of 6 (4 – 9) blotches. The blotches form four rows of transverse mostly circular blotches. The dark blotches on the rear legs are circular in shape and do not form into bands with the average number of leg blotches being 8 (4 – 14). Most individuals have black lateral spots on the abdomen and these average 2.6 (0 – 5). The average number of femoral pores on the left leg is 14 (10 – 19). The female body color is greenish yellow during the breeding season but they do not acquire orange on the throat in either sex.Published as part of Hibbitts, Toby J., Ryberg, Wade A., Harvey, Johanna A., Voelker, Gary, Lawing, A. Michelle, Adams, Connor S., Neuharth, Dalton B., Dittmer, Drew E., Duran, C. Michael, Wolaver, Brad D., Pierre, Jon Paul, Labay, Benjamin J. & Laduc, Travis J., 2019, Phylogenetic structure of Holbrookia lacerata (Cope 1880) (Squamata: Phrynosomatidae): one species or two?, pp. 139-154 in Zootaxa 4619 (1) on pages 148-149, DOI: 10.11646/zootaxa.4619.1.6, http://zenodo.org/record/324848