CYTOGENETIC ABERRANCY AND ORGANOCHLORINE PESTICIDE ACCUMULATION IN THE MEXICAN FREE-TAILED BAT:

A COMPARISON BETWEEN OKLAHOMA AND NEW MEXICO POPULATIONS

Degree: Doctor of Philosophy in Zoology

Date of Degree: May, 1993

Dissertation Advisor: Dr. Karen McBee

Institution: Oklahoma State University, Stillwater, Oklahoma

Major Field: Wildlife and Fisheries Ecology

Scope and Method of Study: Organochlorine (OC) pesticide accumulation, frequencies of chromosomal aberrancy, and nuclear DNA content variation were monitored in populations of Mexican free-tailed bats (Tadarida brasiliensis) collected from Carlsbad Caverns, New Mexico, and Vickery Cave, Oklahoma, during the summers of 1990 and 1991. Pesticide residues in brain and carcass tissues were identified and quantified using electron capture gas chromatography. Chromosomal aberrancy was examined using the standard bone marrow chromosomal aberration assay and nuclear DNA content variation was measured in spleen and testicular tissues using flow cytometry (FCM). Relationships among pesticide content, observed chromosomal aberrancy, and nuclear DNA content variation were examined for statistical differences and possible correlations.

Findings and Conclusions: Both populations demonstrated significant levels of OC contamination; however, the Carlsbad Caverns population showed consistently higher pesticide loads. Males also demonstrated higher levels as compared to females. Transfer of pesticides across the placenta into developing embryos was observed in both populations. No statistical differences in chromosomal aberrancy or nuclear DNA content variation were observed among sexes, sites, or collection periods. No correlations among OC contamination and genetic assays were found for females. Males, however, showed significant positive correlations among brain and carcass DDE concentrations and negative correlations among spleen FCM and brain DDE concentration.

Associated publications:

·         Thies, M., and D. Gregory. 1994. Residues of lead, cadmium, and arsenic in livers of Mexican free-tailed bats. Bulletin of Environmental Contamination and Toxicology 52:641-648.

·         Thies, M., K. Thies, and K. McBee. 1994. Cross-placental transfer of organochlorine pesticides in the Mexican free-tailed bat. Archives of Environmental Contamination and Toxicology 27:239-242.

·         Thies, M., K. Thies, and K. McBee. 1996. Organochlorine pesticide accumulation and genotoxicity in Mexican free-tailed bats from Oklahoma and New Mexico. Archives of Environmental Contamination and Toxicology 30:178-187.


SPATIAL DISTRIBUTION OF NEOTOMA MICROPUS NESTS IN SOUTHWESTERN OKLAHOMA

 

Degree: Master of Science in Biology

Date of Degree: December, 1987

Thesis Advisor: Dr. William Caire

Institution: University of Central Oklahoma, Edmond, Oklahoma

Major Field: Field Biology

Abstract: This study examined the dispersal patterns of 1129 nests of a natural population of Neotoma micropus. The study plot (475m by 1609m) was located approximately 8km southwest of Hollis, Harmon Co., Oklahoma. Dispersion patterns were analyzed using a Poisson comparison method, a nearest-neighbor method, and Holgate's point-to-nest distance ratio method. These three methods suggested that the woodrat nests were distributed in an aggregated pattern across the study plot. Vegetation occurring within the study area which was utilized in nest construction was characterized by a tine transect method. Prickly-pear cactus (Opuntia phaeacantha and O. cymochila) and mesquite (Prosopis julioflora) were determined to be the dominant plant species on the study plot. The extent of coassociation between the woodrat nests and those plant species involved in their construction was examined using 2x2 contingency tables, Phi-2, Cole's C7, and Hurlbert's C8 coefficients of association. Positive correlations were observed only for the two Opuntia species occurring on the plot.

The structure of the woodrat population on the study plot was examined by live trapping individuals from 52 active nests. From the data collected, a density of 1.71 woodrats per nest was determined. A total of 1931 woodrats was estimated to occur on the entire study plot, with a density of 25.7 woodrats per hectare. Sex ratios were determined to be 1:1. Utilizing fluorescent powders to facilitate night tracking, home range size and number of nests utilized by individual rats were examined. Home ranges were not significantly different for male and female woodrats, with male home range estimates to be 1502m2 and 343m2 for females. Limited tracking data indicated that woodrats moved between adjacent nests but did not travel far from the nest sites where they were captured.

Associated publications:

·         Thies, M., and W. Caire. 1990. Association of Neotoma micropus houses with various plant species in southwestern Oklahoma. Southwestern Naturalist 35:80-82.

·         Thies, M., and W. Caire. 1991. Nearest-neighbor analysis of the spatial distribution of houses of Neotoma micropus in southwestern Oklahoma. Southwestern Naturalist 36:233-237.

·         Thies, K., M. Thies, and W. Caire. 1996. House construction by the southern plains woodrat (Neotoma micropus) in southwestern Oklahoma. Southwestern Naturalist 41:116-122.


ABSTRACTS FOR COMPLETED STUDENT MASTERS THESES:

 

GAR ICHTHYOOTOXIN: ITS EFFECT ON NATURAL PREDATORS AND THE TOXIN’S EVOLUTIONARY FUNCTION

Kenneth G. Ostrand

Master of Arts in Biology, May 1995.

Primary Thesis Advisor: Darrell D. Hall

Sam Houston State University, Huntsville, Texas.

Sam Houston State University, Huntsville, Texas

Abstract: Spotted gar (Lepisosteus oculatus) and alligator gar (L. spatula) roe were fed to green sunfish (Lepomis cyanellus) and channel catfish (Ictalurus punctatus) at a rate of 2 eggs/g of body weight for 14 days. The dosage, equivalent to the LD50 established for small mammals and crayfish, did not result in mortality of these fish. Further, our study showed that fish fed gar roe maintained or gained weight, which leads to the conclusion that these fish do not reject the gar roe as a food source. Consumption of gar roe by potential natural predators, such as L. cyanellus and I. punctatus, establishes the basis for the argument that gar roe toxin has not been evolutionarily selected to serve as a protective mechanism. Gar roe may simply be toxic to small mammals and crayfish by chance.

Associated publications:

·         Ostrand, K. G., M. Thies, D. D. Hall, and M. Carpenter. 1996. Gar ichthyootoxin: Its effects on natural predators and the toxin’s evolutionary function. Southwestern Naturalist 41:375-377.


 

Description: http://www.shsu.edu/~bio_mlt/gate.jpg

AN EVALUATION OF THE U.S. ARMY’S SATELLITE IMAGERY BASED SITE SELECTION PROCESS

John P. McHugh

Master of Arts in Biology, May 1996.

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas.

Description: http://www.shsu.edu/~bio_mlt/Plot19.jpg

Abstract: The effectiveness of the site selection process for determining Land Condition Trend Analysis (LCTA) plots was examined. The sixty plots chosen using the satellite image based selection process were field-sampled, then categorized into 14 different plant community types using ecological ordination and classification procedures. Surface geology was examined to see if there were consistent patterns between geology, the image clusters, and the vegetation communities. In addition, the 5:4 and normalized difference vegetation index (NDVI) band ratios were used to compare the spectral values with the spectral values for the seven raw TM bands. This was done to see which method provided the closest match to the vegetation. Results suggest the site selection process used in this study did not adequately represent the different vegetation communities for the study area. Surface geology did not indicate any consistency with the imagery clusters or the vegetation. Furthermore, the 5:4 and NDVI band ratios provided better delineation between forested versus non-forested areas than the seven raw TM bands that were used in the site selection process. Suggestions for improvement in the site selection process would be to use various band ratios for additional spectral data into the maximum likelihood classification, and using ancillary data other than surface geology or soil types.


 

Description: http://www.shsu.edu/~bio_mlt/pine.jpg

BIRD AND SMALL MAMMAL HABITAT ASSOCIATIONS AT CAMP NAVAJO ARMY DEPOT, ARIZONA: IMPLICATIONS FOR MANAGEMENT.

Gregory P. Creacy

Master of Arts in Biology, December 1996.

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas.

Description: http://www.shsu.edu/~bio_mlt/HLiz.jpg

Abstract: Bird and small mammal habitat associations at Camp Navajo Army Depot, Arizona were identified, and the effects of military activities on those habitats were investigated. The study was conducted in association with the Land Condition Trend Analysis Program (LCTA) in an effort to determine future needs for natural resource management. Study results indicate that the installation has not been significantly impacted by military training activities. Evidence of previous military activities was sparse, and study sites with evidence of activities did not significantly differ from sites with no evidence with regard to frequencies of early successional, or invasive, plant species. A positive correlation (r = 0.413, P = .002) between invasive plant species and Chipping Sparrow abundance suggests the possible benefit of this bird species as a bioindicator of increased habitat disturbance. Cluster analysis revealed five major habitat types on the installation, each with distinctly different bird and small mammal assemblages. Species richness, species diversity, breeding bird density, and total numbers of birds and small mammals were lowest within the densely forested Ponderosa pine habitat type. Most bird species preferred the “open” Ponderosa pine habitat type, whereas small mammals were most abundant within habitats containing Gambel oak. Mann-Whitney univariate analyses and multivariate logistic regression analysis were used to determine specific habitat associations for each bird and small mammal species. This information, together with results from cluster analyses, was used to predict effects of habitat modification on each bird and small mammal species. Results from this study indicate that a proposed ecological restoration of Ponderosa pine forests within Camp Navajo Army Depot would benefit most wildlife species in addition to restoring natural forest density and structure. Minor thinning of the densely forested areas and the re-introduction of fire through prescribed burning should have either no effect or a positive effect on 29 of the 33 species (88%) examined in this study.


 

Description: http://www.shsu.edu/~bio_mlt/dixie1.jpg

SPECIES ASSEMBLAGES AND HABITAT PREFERENCES OF RODENTS ON SOUTH TEXAS RANGELANDS.

Denise M. Ruffino

Master of Arts in Biology, May 1997.

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas.

Description: http://www.shsu.edu/~bio_mlt/dixie2.jpg

Abstract: Six sites were evaluated on the Dixie Target Site and Escondido Ranch (DTSER), McMullen Co., Texas, to determine the effects of microhabitat variables on rodent assemblages and habitat preferences. Soil, vegetation, and capture data associations were investigated to: ascertain relationships between species diversity and particular components within each site, estimate the effects of seasonal changes on assemblage diversity, and assess the degree of variability in certain rodent species to utilize multiple habitats. Study results indicated nine species of rodents inhabiting the study sites, with a prevalence of Peromyscus leucopus throughout the entire study area. Cluster analyses, using discriminant function and correlation analysis, were performed for soil, vegetation, and capture data and revealed limiting characteristics used to sort sites by their degree of dissimilarity. A strong dependence upon sandy soils with a high organic content; vegetation within the Cactaceae, Euphorbiaceae, and Ebenaceae families; and the occurrence of Baiomys taylori, Onychomys leucogaster, and Dipodomys compactus, were primary criteria for differentiating between the site assemblages. Seasonal differences in assemblage diversity were examined to determine if any direct impact was observed. Rodent populations remained stable throughout the study and seasonal fluctuations were not found to significantly affect rodent assemblages on any site.

Three species were classified as generalist species (P. leucopus, Sigmodon hispidus, and Reithrodontomys fulvescens), occurring on multiple sites, while four species were found to exhibit specialist behavior (Neotoma micropus, Perognathus merriami, O. leucogaster, and D. compactus). Results for B. taylori and Chaetodipus hispidus were inconclusive. Since correlation analysis selects for rare variables, the effects of generalist rodent species or predominant species, floral or faunal, on assemblages could not be determined.


 

FIRST RECORD OF HYDRA SP. FROM AN ANCHIALINE CAVE IN QUINTANA ROO, MEXICO

James G. Coke, IV

Master of Science in Biology, December 1998.

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas.

Abstract: The Yucatan Peninsula of Mexico is a remarkable karst platform that is the consummation of numerous marine transgressions since the Cretaceous period. Warm shallow seas deposited over 2 km of carbonate sediments in this region, antecedent to an interlude of gradual uplift commencing during the Tertiary. These processes shaped a relatively stable karst terrain that is predisposed to the dynamics of speleogenesis. Sea level fluctuations during the Pleistocene accelerated initial Tertiary cave development. With the close of the Pleistocene, cave systems on the eastern coast of Quintana Roo were ultimately submerged in an anchialine environment.

Anchialine caves in Quintana Roo are immersed in fresh and saltwater zones that fluctuate with oceanic tides. Organic nutrients from the epigean environment enter the caves at various locations through karst windows called cenotes. Habitat diversity and nutrient availability supports multifarious cave-adapted species only recently discovered by underwater cave research.

Two freshwater species of Cnidaria (Class Hydrozoa) have been discovered in the siphon region of the Carwash Cave System in Quintana Roo, Mexico. This is the first record of Hydra oligactis and Hydra viridissima from anchialine caves.

Population and taxonomic studies were conducted during July-August 1998 and October 1998. Populations of Hydra viridissima were observed in primary freshwater drainage tunnels as distant as 75 m from the cave entrance. Hydra oligactis populations were observed in primary and secondary freshwater drainage tunnels 175 m distant from the cave entrance. Statistical comparisons of transect data for habitat partialities were inconclusive.

Taxonomic methods consolidated a congruent aggregate of reliable characters for classification. Hydra oligactis was identified by lateral tentacle development on incipient buds, holotrichous isorhiza morphology, and relative tentacle to column length. The systematics of “green” hydra remains controversial. Alga symbiosis, simultaneous tentacle development on incipient buds, and relative tentacle to column length identified Hydra viridissima. Unsuccessful attempts at laboratory cultures precluded taxonomy based on reproductive structures.

Water chemistry studies allude to increasing levels in ammonia, nitrates, and phosphorus in the freshwater aquifer. Survey data suggest that chemical contamination of the aquifer may originate from a municipal dumpsite.


 

PESTICIDE ACCUMILATION AND ITS POTENTIAL FOR GENETIC EFFECTS IN MEXICAN FREE-TAILED BATS FROM CENTRAL TEXAS

Wendy Armstrong

Master of Science in Biology, May 2000

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Abstract:


 

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PESTICIDE CONTENT AND DNA CONTENT VARIATION IN TWO SUBSPECIES OF MEXICAN FREE-TAILED BATS IN EAST TEXAS

Brad Bennett

Master of Science in Biology, May 2000

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Abstract:

Associated publications:

·         Bennett, B. S., and M. L. Thies.  2007.  Organochlorine Pesticide Residues in Guano of Brazilian Free-tailed Bats, Tadarida brasiliensis Saint-Hilaire, from East Texas. Bull. Environ. Contam. Toxicol. 78:191-194.


 

SEASONAL CHANGES IN SPERMATOGENESIS IN THE BRAZILIAN FREE-TAILED BAT

Jennifer Wier

Master of Science in Agriculture, May 2003

Thesis Co-advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Abstract:

 


 

MORPHOLOGICAL AND MITOCHONDRIAL VARIATION BETWEEN TWO SUBSPECIES OF MEXICAN FREE-TAILED BATS

O. Caprice Coleman

Master of Science in Biology, December 2004

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Description: DraI

Abstract: In the United States, two subspecies of Brazilian free-tailed bats, Tadarida brasiliensis (Chiroptera; Molossidae), are currently recognized.  T. b. cynocephala are considered permanent residents found from east Texas to Florida.  Migratory T. b. mexicana are distributed throughout the southwest from California to east Texas and as far north as Colorado.  In east Texas, a well-established colony occupies a Texas Department of Criminal Justice warehouse in downtown Huntsville.  This colony is located in an area where the ranges of the two subspecies overlap.  Vestiges of the population present in the winter are proposed to be resident T. b. cynocephala whereas the population increase in the summer is thought to be migratory T. b. mexicana.  Due to overlap in body size between the two subspecies, morphometric data alone is not a reliable determining factor for subspecies designation.  Use of mitochondrial DNA (mtDNA) sequence data combined with Restriction Fragment Length Polymorphisms (RFLP) and Randomly Amplified Polymorphic DNA (RAPD) showed that subspecies designations for T. b. cynocephala and T. b. mexicana are not supported.


 

Description: C:\Manuscripts\Debelica - TX Mammal Hair\Atlas Figures\83a.Antilocapra americana.JPG

AN ATLAS AND KEY TO THE HAIR OF TERRESTRIAL TEXAS MAMMALS

Anica Debelica

Master of Science in Biology, August 2005

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Description: C:\Manuscripts\Debelica - TX Mammal Hair\Atlas Figures\83b.Antilocapra americana.jpg

Abstract: Even though some hairlike structures may be found on organisms such as birds, insects, and plants, true epidermal hair is a unique characteristic of mammals.  Samples of guard hairs from 152 mammalian species found in Texas were collected from specimens housed in natural history collections or , as in the case for domestic farm animals, were obtained from living animals.  An atlas and key were developed after examining several characters of hair samples, including average diameter of the hairs, the structure of medulla, and the arrangement of scales in the cuticula.  Digital pictures of the medulla and SEM images of the surface of different hair accompany the key, and should provide a helpful tool that can be used in hair identification by both biologists and criminal investigators.

Associated publications:

·         Debelica, A., and M. L. Thies. 2009. Atlas and key to the hair of terrestrial Texas mammals. Special Publications of the Museum of Texas Tech University, Number 55, 102pp.


 

MORPHOLOGICAL VARIARTION AMONG DOMESTIC RABBIT BREEDS (ORYCTOLAGUS CUNICULUS) WITH A COMPARISON TO WILD STOCK

Katy Estill

Master of Science in Biology, August 2012

Thesis Advisor: Monte L. Thies

Sam Houston State University, Huntsville, Texas

Abstract: Domestication of rabbits began 1,500 years ago with captive breeding of the European wild rabbit, Oryctolagus cuniculus (Linnaeus, 1758). Selective breeding resulted in a high degree of variability in external morphology and pelage, with 47 breeds of rabbits currently recognized in the US. These breeds, designated by the American Rabbit Breeders Association (ARBA), are often inaccurately described in scientific literature and are commonly described by size alone, or with an incomplete or inaccurate description. Without correctly defining the breed being used, research cannot be reliably replicated. This study illustrates that skeletal elements from four domestic rabbit breeds, and museum specimens from the National Museum of Natural History, can be delineated through morphological studies of the skull. This study also confirms allometric scaling between breeds as previously found in breeds.  In addition, hair samples from the rabbit breeds used are shown to be morphologically distinct when considering hair type of the specific breed. Currently there is no collection of domestic breeds, so in addition to completing a morphological study, individuals obtained were prepared as museum specimens and accessioned into the Sam Houston State University Vertebrate Museum.