The Effects of a River Closure on a Snook (Centropomus spp.) Nursery Community in the Rio Grande River, Texas

Nesting by the endangered Kemp's ridley sea turtle Lepidochelys kempii has increased on the Texas coast during recent years. Movements of 28 individual adult females that nested on North Padre Island or Mustang Island, Texas, USA, were monitored using satellite telemetry. Plat- form transmitter terminals (PTTs; n = 36) were deployed on the 28 turtles between 1997 and 2006, with 1 individual receiving 3 PTTs during different years, 6 receiving 2, and 21 receiving 1. Of the 28 individuals, 17 were from the wild stock, 9 were head-started turtles (reared in captivity for the first months of life) that had been experimentally imprinted to Padre Island as hatchlings, and 2 were head-started turtles that had been obtained directly from Mexico as hatchlings. Locations were obtained from 9 to 841 d (mean = 277 d) following deployment. After they completed nesting for the season, most of the tracked turtles left south Texas and traveled northward, parallel to the coastline, with their last identified location in the northern or eastern Gulf of Mexico. Inter-nesting residency was documented off south Texas and post-nesting residency in USA Gulf of Mexico waters from south Texas to the tip of Florida. Movements and habitat utilization by wild and head-started turtles and by individuals during different tracking events were generally similar. However, all of the 5 tur- tles that briefly traveled southward to waters off the coast of Mexico were wild. Tracking data were used to aid with nest detection and protection, and development of a regulation by Texas Parks and Wildlife Department that closed near-shore south Texas waters to shrimp trawling. Findings from this study demonstrate the importance of near-shore Gulf of Mexico waters, particularly offshore from south Texas, to post-nesting Kemp's ridley turtles.

Seasonal Timing, Geographic Distribution, and Flight Behavior of Broad-Winged Hawks During Spring Migration in South Texas: A Radar and Visual Study

This study investigated the contribution of shrimp stocks in supporting the production of valuable predator species. Fishery-independent data on white shrimp, brown shrimp, and selected fish species (spotted seatrout, red drum, and southern flounder) were collected from 1986 to 2014 by the Texas Parks and Wildlife Department, and converted to catch-per-unit effort (CPUE). Here, the associations between the CPUEs of fish species as predators and those of shrimp species as prey in each sampled bay and sampling season were analyzed using co-integration analysis and Partial Least Squares Regression (PLSR). Co-integration analysis revealed significant associations between 31 of 70 possible fish/shrimp pairings. The analysis also revealed discernible seasonal and spatial patterns. White shrimp in August and brown shrimp in May were associated with fish CPUEs in bays located along the lower coast of Texas, whereas white shrimp in November was more strongly associated with fish CPUEs in bays located on the upper coast. This suggests the possible influence of latitudinal environmental gradient. The results of the PLSR, on the other hand, were not conclusive. This may reflect the high statistical error rates inherent to the analysis of short non-stationary time series. Co-integration is a robust method when analyzing non-stationary time series, and a majority of time series in this study was non-stationary. Based on our co-integration results, we conclude that the CPUE data show significant associations between shrimp abundance and the three predator fish species in the tested regions.

Irrigation is important in many crop production systems. However, irrigation water can be a carrier of plant pathogens that can enter the system and spread to fields, resulting in crop damage and yield losses. The Lower Rio Grande Valley of South Texas is an important area for agricultural production which depends on the Rio Grande River as a source of water for irrigation. Thus, the presence of plant pathogens in the Rio Grande River could have important implications for crop productivity in the region. Cultured-based methods and molecular identification methods are used for monitoring plant pathogens in irrigation water. However, these methods are labor-intensive and just detect targeted pathogens. To overcome these limitations, in this study, the ITS2 amplicon metagenomic method was applied for evaluating the fungal diversity, composition, and presence of fungal plant pathogens in irrigation water from the Rio Grande River as it leaves the water reservoir (WR) and it arrives at an irrigation valve at a farm (FA). Results from the Shannon (WR = 4.6 ± 0.043, FA = 3.63 ± 0.13) and Simpson indices (WR = 4.6 ± 0.043, FA = 3.63 ± 0.13) showed that there are significant differences in the fungal diversity and community structure between the two locations and the PCA analysis showed a clear differentiation between both fungal communities. Several OTUs identified in both locations included potential plant pathogens from diverse genera including Cladosporium, Exserohilum, and Nigrospora, while others such as Colletotrichum and Plectosphaerella were found only in one of the two locations assessed. This work indicates that microbes, including plant pathogens, may enter or exit throughout the irrigation-water distribution system, thereby modifying the microbial community composition along the way. Understanding the dynamics of plant pathogen movement in irrigation water systems can help growers identify risk factors to develop measures to mitigate those risks. This study also shows the usefulness of the metagenomic approach for detecting and monitoring plant pathogen in irrigation water.

There are currently 63 fixed steel platforms in the Gulf of Mexico (GoM) in water depths greater than 400 feet. Most of these platforms will have jacket weights in excess of 10,000 short tons. In the context of this paper, the aforementioned parameters define deepwater platforms. Any of these platforms would set a new GoM decommissioning record in terms of size and depth. A number of these platforms have been identified and are being planned for decommissioning within the next few years. Assessing the relevant technology for decommissioning and its resulting cost is a challenge for all concerned. Offshore platform decommissioning is a challenge under any circumstances in terms of planning and executing the work in an environmentally sensitive, safe, and economical way. Among the issues that must be faced are limited availability of equipment and the capability of current technology to adapt to the depths faced in deepwater. This paper presents the potential issues (resources, technologies, and methodologies) that may be encountered in decommissioning deepwater platforms. Fixed conventional platforms in water depths greater than 400 feet are identified and summarized. GoM platform removals case histories are presented to show the various decommissioning options executed to date. The paper concludes in summarizing the regulatory environment that will affect the decommissioning of deepwater platforms. Introduction Table 1 summarizes the GoM fixed steel platforms in water depths greater than 400. Most of these platforms are selfcontained multi-well drilling and production. Early installations are in a six to eight leg configuration. Later designs such as Pompano (VK 989 A) reduced the legs to four, but added multiple skirt piles around each leg. Platforms such as ST 192 A and SP 89 E were designed as a junction between deepwater developments and shallow water pipeline transmission systems. As shown in Figure 1, the deepwater platforms lie near or outside the continental shelf with a greater concentration in Louisiana waters. The orange outlined areas in Figure 1 are the designated artificial reef sites that are managed by either the Texas Parks and Wild Life Department or the Louisiana Department of Wild Life and Fisheries in the western and central planning areas. The decommissioning options available for deepwater platforms are the same as those in shallower shelf platforms. Figure 2 shows the overall production facilities, deck and jacket disposal options. In general all options executed take the production facilities and decks to shore for storage or disposal. The underlying difference is the fate of the jacket. The Complete Removal option takes the conductors and jacket to shore for disposal or storage for future reuse. Remote Reef options assumes that the conductors are removed and disposed onshore and the jacket rigged, lifted, towed and placed at a remote artificial reef site. Topple in-Place is where the jacket and conductors are pulled over into a horizontal position and toppled creating an artificial reef site.

For decades there has been a noticeable decline in northern bobwhite (Colinus virginianus; hereafter, bobwhite) populations. Few studies have assessed the survival of translocated bobwhite. We evaluated the effectiveness of reintroduction of bobwhite into the Texas (USA) Parks and Wildlife Department’s Gus Engeling Wildlife Management Area (GEWMA), where they had been extirpated but now have suitable habitat. Before reintroduction, GEWMA was surveyed (spring call counts) to make sure no bobwhite were present. Forty-six bobwhite were trapped from March–April 2019 in South Texas, banded, bled, radio-tagged, transported to GEWMA, and released. In addition, 17 bobwhite were trapped banded, bled, radio-tagged, and released back into the source population as a control for comparison of movements, reproduction, and survival estimate differences between the source and released bobwhite populations. During July 2019, 3 broods (24 bobwhite) were trapped and translocated from a South Texas ranch to the GEWMA. Survival for bobwhite released at GEWMA was 37.0% through 1 July 2019 and 70.6% for bobwhite left on the ranch in South Texas. Three nests were found at GEWMA while none were found on the ranch in South Texas. Movement distances between daily locations for males and females did not differ at GEWMA or at the ranch in South Texas; however, there was a significant (P ≤ 0.001) difference in daily movement for bobwhite at GEWMA and the South Texas ranch. Female bobwhite at GEWMA moved 5.4 times the distance of female bobwhite in South Texas and male bobwhite at GEWMA moved 5.9 times the distance of male bobwhite in South Texas. Bobwhite at GEWMA were located in woody cover only 24.2% of the time, whereas bobwhite in South Texas were located in woody cover 76.1% of the time. The greater daily movement and less use of woody cover for bobwhite at GEWMA probably contributed to their lower survival.

White spot syndrome virus (WSSV) is a virulent disease that disrupts shrimp farm operations throughout the world. While the United States has had only limited outbreaks of WSSV within the past several decades, it is important to ensure that this disease does not infect wild penaeid shrimp populations. In Texas, there is a potential for WSSV to spread to wild penaeid populations in the Gulf of Mexico via infected imported nonnative bait shrimp, imported broodstock, or wild crustacean hosts. Due to these potential threats, the Texas Parks and Wildlife Coastal Fisheries Division monitored WSSV in wild brown shrimp Farfantepenaeus aztecus and white shrimp Litopenaeus setiferus from seven major bay systems along the Texas coast during 2019. While no positive samples were detected from the collected shrimp, a power analysis illustrated a potential for low-level WSSV prevalence within Texas shrimp populations that would not be detectable by this monitoring survey. Overall, WSSV does not appear to be a major threat in the Texas region of the Gulf of Mexico, but continual observation and monitoring of wild penaeid shrimp is necessary to protect this resource from future WSSV outbreaks.

Deer Ked Infestation on White-Tailed Deer in East Texas

Initial results of environmental monitoring in the Texas Rio Grande Valley

In the Gulf of Mexico, the distinction between natural and artificial resources has become obscure. Over one quarter of the hard substrate existing offshore has been created by the steel legs of nearly 4,000 petroleum platforms. The encrusting organisms and reef fish communities established on and below these jackets have literally had their ranges extended, their numbers increased, their diversity preserved. There can be no doubt as to the habitat limitations of these species in the open ocean, dependent as they are on something solid rising out of the endless expanses of soft sediments. Man's search for oil and gas has had a positive affect on the reef fish community in the Gulf of Mexico. The Texas Artificial Reef Program established by the Texas Parks and Wildlife Department in 1990, has been actively acquiring offshore platforms for use as artificial reefs in the Gulf of Mexico. The donation of an obsolete platform prevents the loss of the structure's valuable benthic reef habitat and associated recreational opportunities. A donation of a platform to the Artificial Reef Program also results in considerable savings compared to standard removal options for the donor. Since the Program was created, 39 rigs donated by 20 different petroleum companies have been converted into artificial reefs, which enhance the reef fish resources in addition to providing exciting new fishing and divingopportunities for Texas. The Texas Artificial Reef Program also offers some interesting new opportunities to the petroleum industry. Eleven reef sites are already established within a 2500 square mile area designated as a General Permit for the High Island Leasing (OCS) Area. The Corps of Engineers (COE) has permitted this entire area so that artificial reefs may be created at least five nautical miles apart, two nautical miles from any safety fairways, with at least 85-ft of clearance. Specific hard bottom communities (such as the Flower Garden Marine Sanctuary East and West Bank) are excluded from TPWD's General Permit and require an individual permit from the COE before a platform can be accepted as an artificial reef. The Department has been working closely with the U.S. Department of the Interior's Minerals Management Service (MMS) to allow the use of alternative removal methods, where the structure is being mechanically removed and made into an artificial reef. Texas received the donation of six jackets mechanically removed 3-ft below the mudline, and transported intact to an appropriate reef site by Mobil Oil Company to the Texas Artificial Reef Program. Texas also received the donation of four jackets where the upper 85-ft of these jackets was partially removed by mechanical means, and placed on the bottom next to the lower portion of the jacket to order to create a higher profile artificial reef in deep water. This type of donation allows for the maximum biological profile in the water column within current Coast Guard regulations and allows the creation of artificial reefs without the use of explosives, which are responsible for loss of reef fish in the open water column and the benthic habitat attached to the structure.

Objective The Atlantic Tripletail Lobotes surinamensis is a globally distributed subtropical and tropical fish species that inhabits estuaries throughout the northern Gulf of Mexico (GOM), particularly during warm months. Little is known about distribution and residency patterns within estuaries, as the species is rarely caught in the recreational fishery, and virtually no commercial fishery exists for the species in the GOM. Methods We used data from a long-term fishery-independent gill-net survey to model estuarine distribution throughout Texas and to relate environmental variables to the Atlantic Tripletail catch. Result Although there were no observable temporal trends in catch over the time series (1990–2022), the most recent 6 years included record catch in six of the 10 major Texas estuaries, possibly indicating a recent pulse in abundance. Catch throughout the time series was spatially aggregated in a small number of “hot spots” observed coastwide. Latitude was the best predictor of catch, although wind fetch and wind aspect (wind direction in relation to shoreline direction) were important predictors, and catch was highest near GOM inlets. The Texas Parks and Wildlife Department gill-net sampling program caught a range of Atlantic Tripletail between 171 and 880 mm total length, indicating a potential gear bias against juveniles. Conclusion Despite this gear bias, these data shed light on the factors that drive Atlantic Tripletail estuarine distribution and abundance in the northwestern GOM. Wind-driven passive movements in the estuary, combined with active selection of polyhaline habitats near GOM inlets, might be primary drivers of Atlantic Tripletail catch, thus supporting findings from previous studies. Abstract Impact statement Atlantic Tripletail are a popular recreational fishing species throughout the Gulf of Mexico. In Texas estuaries, Atlantic Tripletail are clustered in hot spots, which are typified by windward shorelines, and present mainly during the high-use fishing season. They are rarely observed at water temperatures below 20°C.

The presence of cryptic species can hinder effective conservation planning and implementation, as has been the case for speciose groups of freshwater fishes that are difficult to differentiate due to conserved morphologies. The West Texas shiner Notropis megalops and the Texas shiner Notropis amabilis are a cryptic pair of leuciscids (minnows) that co-occur in spring-fed tributaries of the Rio Grande in Texas and Mexico. Both N. megalops and N. amabilis are listed as Species of Greatest Conservation Need by the Texas Parks and Wildlife Department. Notropis amabilis is widespread and listed as apparently secure by Texas Parks and Wildlife Department whereas N. megalops has a very limited distribution and has not been ranked by Texas Parks and Wildlife Department because of data deficiency. Morphological differences between these species have been described; however, proper identification in situ remains problematic. Furthermore, given their range of overlap there is potential for hybridization, and limited genetic data have been collected comparing the species. Therefore, reduced representation genomic and mitochondrial sequencing data were used to reassess the distinctness of the species, screen for hybridization, and characterize their relative frequencies throughout their range of overlap. Genomic analyses recovered two distinct genetic groups corresponding to the species (F'CT = 0.89) with no evidence of admixture or introgression. The species were found to co-occur at three sampling locations, two in the Devils River and one in the Pecos, but not in equal frequencies. Overall, these results provide data and tools for further research on N. megalops needed for accurate conservation policies and management practices.

Reclaiming Texas Brushland Range

This is the final report for the red tide monitoring project conducted at The University of Texas at Austin Marine Science Institute (UTMSI) and covers the period from 1 Nov. 1998 to 10 April 2000. The study was designed to examine the seasonal dynamics of the toxic red tide dinoflagellate Karenia brevis (Davis) G. Hansen and Moestrup at 5 locations off the Texas coast. The work was conducted in collaboration with the Texas Parks and Wildlife Department (TPWD) utilizing bimonthly finfish surveys (Coastal Fisheries Division) to collect samples. The samples were shipped to UTMSI for chl a, nutrient, and cell count analyses. Significant interannual variability occurred in the temperature and salinity fields. Temperature was lowest in Jan.-Feb. of each year and increased. In general, the 5 stations showed little concordance with each other. There was no annual pattern in nutrient distributions. Individual stations appeared to reflect local inputs, rather than coast wide events. The only exception was a generalized silicate increase noted in Feb-April 2001 at all stations except Brazos Santiago near Brownsville. Karenia brevis was observed sporadically along the coast during the winter and most observations were limited to the summer/fall months. The sporadic occurrences and numerous no observations do not support the hypothesis that a year round resident red tide population exists in the Texas coastal zone. It appears that are transported into the area by large scale oceanographic features. The mechanism for this remains unknown. A minor red tide occurred along South Padre Island in Oct./Nov 1999. The bloom advected south into Mexico, and no further fish kills were noted in 1999. However, K. brevis occurred sporadically along the coast during this time. These events suggest that K. brevis may be seeded into the area from further offshore regularly at very low levels. Until fish-killing populations develop, it likely remains undetected. One major red tide event occurred during 2000 that affected the entire Texas coast. A small red tide occurred along South Padre Island in July, 2000 but disappeared after moving north to Padre Island National Seashore. Fish-killing concentrations of K. brevis were first detected in mid August off Sabine Pass in the north and moved south along the coast over the following months. However, low level occurrences of K. brevis were found at intermediate stations well before the main red tide advected into the region, and were nearly coincident with the initial observations off Sabine Pass. It is impossible from this data to determine if the July bloom in south Texas was related to the events off Sabine, but there is a possibility that offshore continental shelf currents may well be transporting cells north from Mexico into northern Texas waters. Another toxic species closely related to K. brevis has been seen at reasonably high abundance. This species, Karenia mikimotoi, is toxic to fish and has been reported to co-occur with K. brevis in blooms. Maximum abundance of this species was 6000 cells L-1, and appeared to exhibit a distinct increase and decline in population levels at 3 different stations.

Understanding patterns in terms of the mechanistic processes that produce them is the essence of ecology. However, many studies merely document nonrandom patterns of species coexistence without providing insight into the structuring mechanisms and their scale dependence. Moreover, few studies address the mechanisms driving functional diversity. The objectives of this study were to document empirical patterns of species coexistence within stream fish assemblages across a broad geographic region, addressing both the functional and taxonomic organization of those assemblages, and to determine whether the structuring mechanisms are scale dependent. We gathered data from a report published by the Texas Parks and Wildlife Department that provided empirical species abundance distributions for 62 assemblages from 7 ecoregions and 18 river basins. For each assemblage, we simulated expected species abundances using five previously published models of niche apportionment. These models generate relative abundances in proportion to niche breadth and are constrained to maintain observed species richness, but they do not include information on species identity. These models included four stochastic variants of a geometric series (dominance preemption, random fraction, broken stick, and dominance decay) in which species abundances relate directly to niche breadth and one model (random assortment) in which abundances are independent of niche partitioning altogether. To assess scale dependence, we repeated the analyses after pooling assemblages by ecoregion, river basin, and the entire state. The patterns of niche apportionment for assemblages pooled according to river basin are more consistent with local assemblages than with assemblages pooled according to ecoregions or the entire state. These results suggest that niche apportionment plays a crucial role in structuring stream fish assemblages and that functional groups divide niche space more evenly than do species.