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The physiological tolerances of invasive species can be important predictors of geographic range expansion. Further, determining salinity tolerances can inform natural resource managers as to the ability of a freshwater species to invade estuarine habitats. Native to South America, the island apple snail Pomacea maculata (family Ampullariidae) is an invasive freshwater gastropod that is currently established across much of the southeastern United States, including South Carolina. The island apple snail is considered an invasive species because of the negative impacts of its intense grazing, high fecundity, and ability to out-compete native species. Further, the island apple snail can also serve as a potential to host the rat lungworm nematode parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans. Despite these known potential impacts, knowledge of biology of P. maculata in South Carolina is limited. The objective of this study was to determine the salinity tolerance of P. maculata hatchlings. Although previous studies on the salinity tolerance of P. maculata have been conducted, physiological tolerances can often vary regionally. Because of this potential for regional differences in salinity tolerance, determining the salinity tolerance of P. maculata specific to South Carolina is important in improving the understanding of its invasion/dispersion potential among brackish habitats in South Carolina. This knowledge will help resource managers to develop more effective control and/or eradication strategies. Newly hatched P. maculata obtained from egg clutches deposited by adult snails in a biosecure laboratory were placed in each of five salinity treatments (0, 4, 8, 12, and 16), and mortality was assessed daily for 14 days. Intraspecific variation at the regional scale in salinity tolerance has been documented in other species; thus, the survival of hatchlings from four separate mating pairs was assessed. Kaplan-Meier survival analysis was conducted to determine median survival probabilities, and differences in mean survival were determined using Kruskal-Wallis tests with post hoc Dunn's tests. An L[D.sub.50] value was determined by conducting a logistic regression analysis. A survival of 100% was observed at 0 salinity and 0% survival was observed at salinities of both 12 and 16. Survival probabilities at salinities of 4 and 8 were 0.925 and 0.156, respectively. There were no differences in survival among hatchlings from the different mating pairs. In relation to salinity, an L[D.sub.50] value of 6.39 was calculated. These results demonstrate the ability of P. maculata to survive salinities as high as 8, suggesting that this species could be capable of becoming established in upstream estuarine habitats in coastal South Carolina. KEY WORDS: Pomacea maculata, gastropod, freshwater, non-native, Ampullariidae, INTRODUCTION The ability to predict accurately an invasive species' potential range of impact is paramount in risk assessment, monitoring, and overall management (Stohlgren & Schnase 2006). Further, the physiological tolerances [...]

The impacts of non-native species on native ecosystems can be substantial, and effective management strategies often require a comprehensive understanding of species biology and ecology within the invaded range. The island apple snail Pomacea maculata is an invasive species known to alter the structure and function of wetland habitats. Researchers first reported island apple snails in the United States in Tallahassee, FL, in 2002 and subsequently observed this species in South Carolina (SC) in 2008. The objectives of this study were to document the spatial distribution, phenology and life history, and habitat preference of island apple snails, as well as its association with co-occurring gastropods in SC. Populations were surveyed in stormwater retention ponds throughout coastal SC, where surveyors documented the numbers of live specimens, sex ratios, and the substrate types on which island apple snails deposited egg clutches. The high abundances and year-round presence of egg clutches observed in this study indicate that these populations are successfully reproducing throughout the year, although egg clutch abundance was positively correlated with air temperature. Overall, this study found higher numbers of female P. maculata than males, and that females preferred to lay egg clutches on culverts as opposed to other available substrates. In addition to P. maculata, four other non-native gastropods were documented in stormwater retention ponds. Among these, Melanoides tuberculata and Pyrgophorus parvulus are potential vectors for multiple human diseases and had never before been reported in SC. Understanding the current distribution and life history traits of P. maculata is important for determining the potential for further spread and providing opportunities to protect healthy, natural ecosystems from the impacts of non-native species. KEY WORDS: gastropod, stormwater retention pond, non-native, distribution, freshwater, Melanoides tuberculata, Pyrgophorus parvulus, Pomacea maculata, INTRODUCTION Non-native species can often have detrimental effects on native flora and fauna, potentially reducing biodiversity, disrupting food webs, and altering ecosystem processes (Parker et al. 1999, Carlsson 2006, Boland [...]

Introduction: Preoperative functional MRI (fMRI) and intraoperative awake cortical mapping are established strategies to identify and preserve critical language structures during neurosurgery. There is growing appreciation for the need to similarly identify and preserve eloquent tissue critical for music production. Case Report: A 19-year-old female musician, with a 3- to 4-year history of events concerning for musicogenic seizures, was found to have a right posterior temporal tumor, concerning for a low-grade glial neoplasm. Preoperative fMRI assessing passive and active musical tasks localized areas of activation directly adjacent to the tumor margin. Cortical stimulation during various musical tasks did not identify eloquent tissue near the surgical site. A gross total tumor resection was achieved without disruption of singing ability. At 9-month follow-up, the patient continued to have preserved musical ability with full resolution of seizures and without evidence of residual lesion or recurrence. Conclusion: A novel strategy for performing an awake craniotomy, incorporating preoperative fMRI data for music processing with intraoperative cortical stimulation, interpreted with the assistance of a musician expert and facilitated gross total resection of the patient's tumor without comprising her musical abilities. [ABSTRACT FROM AUTHOR]