Texas is the leading U.S. producer of cotton, and the U.S. is the largest international market supplier of cotton. Risks and uncertainties plague Texas cotton producers with unpredictable weather, insects, diseases, and price variability. Risk management studies have examined the risk reducing capabilities of alternative management strategies, but few have looked at the interaction of using several strategies in different combinations. The research in this study focuses on managing risk faced by cotton farmers in Texas using irrigation, put options, and yield insurance. The primary objective was to analyze the interactions of irrigation, put options, and yield insurance as risk management strategies on the economic viability of a 1,000 acre cotton farm in the Lower Rio Grande Valley (LRGV) of Texas. The secondary objective was to determine the best combination of these strategies for decision makers with alternative preferences for risk aversion. Stochastic values for yields and prices were used in simulating a whole-farm financial statement for a 1000 acre furrow irrigated cotton farm in the LRGV with three types of risk management strategies. Net returns were simulated using a multivariate empirical distribution for 16 risk management scenarios. The scenarios were ranked across a range of risk aversion levels using stochastic efficiency with respect to a function. Analyses for risk averse decision makers showed that multiple irrigations are preferred, and that yield insurance is strongly preferred at lower irrigation levels. The benefits to purchasing put options increase with yields, so they are more beneficial when higher yields are expected from applying more irrigation applications.

The Lower Rio Grande Valley (LRGV) of Texas is an ecologically diverse region in the United States and marks the northernmost extension for many tropical species of plants and animals. Since the early 1900s, 95% of the native Tamaulipan brushlands have been cleared due to agricultural practices and urban development. The plain chachalaca (Ortalis vetula) is a medium sized bird endemic to the native brushlands of the LRGV. In 2003, I trapped and radio-tagged 29 birds (16 males, 13 females) to evaluate the effects of fragmentation on the population dynamics (i.e., survival, mortality, and movements) of this brushland species. My study objectives were to estimate (1) seasonal survival of chachalacas by sex, and (2) ranges, core areas, and movements using radio telemetry. Mammalian predation (43%, n = 6) and unknown (43%, n = 6) deaths accounted for the majority of mortality observed. I found no difference (P > 0.05) in estimated 8-month survival (December 2003-July 2004) between males (S = 0.364, SE = 0.132) and females (S = 0.405, SE = 0.153). In comparing seasonal survival for all birds (males and females combined), I observed a difference (P < 0.05) in survival between the nesting (S = 0.414, SE = 0.103) and breeding seasons (S = 0.917, SE = 0.079). Female ranges (x‾ = 117 ha, range = 42–177 ha) and core areas (x‾ = 23 ha, range = 5–46 ha) during the nesting season were larger than male ranges (x‾ = 41 ha, range = 31–46 ha) and core areas (x‾ =10 ha, range = 7–14 ha) during the same period. During the breeding season, female ranges (x‾ = 59 ha, range = 10–188 ha) and core areas (x‾ = 9 ha, range = 2–33 ha) were similar to male ranges (x‾ = 48 ha, range = 4–130 ha) and core areas (x‾ = 9 ha, range = 1–23 ha). Mean distances between seasons were similar for both sexes (females, nesting, x‾ = 486, breeding, x‾ = 345; males, nesting, x‾ = 184, breeding, x‾ = 292), though females distances generally were greater. Dispersal defined as movement off the Santa Ana National Wildlife Refuge was observed for 3 birds. In 2 cases, a radio-tagged female and male were observed crossing the Rio Grande River (approximately 100-m wide) to habitat in Mexico. Study results suggested mammalian predation may limit the growth of chachalaca populations. Though land use changes such as agricultural uses may not directly limit chachalaca populations in providing cover and food, concentration of populations in remnant native brushlands may serve as ecological “sinks” to the species. Greater range and movement data observed in my study may be attributed to suboptimal habitat (i.e., increased fragmentation) for plain chachalacas.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI Company.

This study examines promotoras from the U.S.-Mexico border. Promotoras are women who live in colonias throughout the border area and who are employed by service provider and community development organizations to do health-related outreach and education with colonia residents. The role of promotoras can be seen from the perspective of culture brokerage; that is, they are mediators between local communities and external actors such as service providers and agencies of the government. As culture brokers, promotoras facilitate the relationship among the local communities, and the system of services and outside resources. The study proposes a conceptual framework through which programs of community health workers in general, and those involving promotoras in particular, can be understood, designed, and implemented.

My dissertation, From Vaqueros to Mafiosos: A Community History of Drug Trafficking in Rural South Texas is an ethnographic study of the impact of the drug trade in South Texas, with a specific focus on Starr County. This dissertation examines drug trafficking along the U.S-Mexico Border at two levels of analysis. First, through historical ethnography, I provide a cultural history of South Texas, as well as a specific history of drug trafficking in Starr County. In doing so, I highlight the different trafficking practices that emerge throughout South Texas’ history, and I document the social changes that develop in Starr County as a result of these illicit practices. The second half of my dissertation, however, is devoted to a contemporary analysis of the impact of the drug trade on the border region by analyzing important social practices in Starr County relating to drug abuse, policing and the criminal justice system, youth socialization and family life. Through ethnography I present the devastating effects of the drug trade and border policing on this Mexican American border community in rural South Texas. / text

Thesis (Ph. D.)--Texas A & M University, 1987. / Vita. Includes bibliographical references (leaves 224-241).

A rural Rio Grande Valley school has continuously performed below the state average on the reading portion of the State Assessment of Academic Readiness. One of the concerns expressed amongst teachers and staff is the student’s lack of desire to read for pleasure or for academic purposes. This study examines the attitudes of students and staff in towards reading by focusing on the school’s reading culture. A mixed methods approach consisting of interviews, participant observation, a focus group, and a survey was employed in this study. The study found that the teachers and students maintained two polarizing perceptions of their reading culture. Based on these findings the following recommendations were made: create a literature-centered curriculum, increase and vary the selection of school library books, and align teachers’ perception with the students’ perception to create a unified reading culture.

I studied the breeding biology and nesting ecology of the Altamira Oriole (Icterus gularis) and Northern Beardless-Tyrannulet (Camptostoma imberbe), two songbirds inhabiting remnant tracts of Tamaulipan brushland of the Lower Rio Grande Valley, Texas during 2002-2003. I found 76 active oriole nests, 7 of which were reused for second broods, for a total of 83 nesting attempts. I estimated that nearly 20% of the oriole breeding population were subadult, or second-year orioles, which is extremely rare for this species. Oriole breeding pairs were found in high densities and may be at their highest level at the study sites since the 1970s. Fifty-nine percent of oriole nests fledged, and 37% failed. Six nests produced Bronzed Cowbird (Molothrus aeneus) fledglings. Vegetation analysis suggests that orioles prefer the tallest trees at the sites in which to place their nests. A greater number of fallen logs near the nest was also a predictor of nest sites, which suggests that orioles prefer scattered woodlands, but also that many of the forests probably continue to shift to a more open, thorn-scrub climax stage. I monitored 28 Northern Beardless-Tyrannulet nests, which were restricted to a smaller number of study tracts than Altamira Orioles. Historical records are lacking for Northern Beardless-Tyrannulets at these sites, but my surveys indicated that there were similar seasonal numbers of tyrannulets at some of the study sites as there were during 1996-1998. Forty-three percent of nests were successful and 57% failed. Higher abundances of epiphytic Spanish moss (Bromeliaceae: Tillandsia usneoides) and ball moss (Bromeliaceae: Tillandsia recurvata) were the most important predictors of nest sites. The continued existence of these two species in South Texas will depend upon the preservation of tall forests, and in the case of the tyrannulet, forests rich in Tillandsia epiphytes.

I studied the breeding biology and nesting ecology of the Altamira Oriole (Icterus gularis) and Northern Beardless-Tyrannulet (Camptostoma imberbe), two songbirds inhabiting remnant tracts of Tamaulipan brushland of the Lower Rio Grande Valley, Texas during 2002-2003. I found 76 active oriole nests, 7 of which were reused for second broods, for a total of 83 nesting attempts. I estimated that nearly 20% of the oriole breeding population were subadult, or second-year orioles, which is extremely rare for this species. Oriole breeding pairs were found in high densities and may be at their highest level at the study sites since the 1970s. Fifty-nine percent of oriole nests fledged, and 37% failed. Six nests produced Bronzed Cowbird (Molothrus aeneus) fledglings. Vegetation analysis suggests that orioles prefer the tallest trees at the sites in which to place their nests. A greater number of fallen logs near the nest was also a predictor of nest sites, which suggests that orioles prefer scattered woodlands, but also that many of the forests probably continue to shift to a more open, thorn-scrub climax stage. I monitored 28 Northern Beardless-Tyrannulet nests, which were restricted to a smaller number of study tracts than Altamira Orioles. Historical records are lacking for Northern Beardless-Tyrannulets at these sites, but my surveys indicated that there were similar seasonal numbers of tyrannulets at some of the study sites as there were during 1996-1998. Forty-three percent of nests were successful and 57% failed. Higher abundances of epiphytic Spanish moss (Bromeliaceae: Tillandsia usneoides) and ball moss (Bromeliaceae: Tillandsia recurvata) were the most important predictors of nest sites. The continued existence of these two species in South Texas will depend upon the preservation of tall forests, and in the case of the tyrannulet, forests rich in Tillandsia epiphytes.

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