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Abstract: Although invasive plants can have transformative effects on native plant communities, studies of the consequences of plant invasion for native fauna are generally restricted to primary consumers. Here we investigate whether an invasive shrub, Lonicera maackii, impacts native amphibians and evaluate evidence for the role of invasive plant-induced alteration of forest understory microclimate as a mechanism driving amphibian responses to L. maackii invasion. We sampled amphibian communities in forest plots with high or low density of L. maackii, and monitored microclimate (temperature and humidity at ground level) in the same forest plots. Amphibian species richness and evenness were lower in invaded plots. Invasion also resulted in shifts in amphibian species composition. Mean daily maximum temperature and mean daily temperature were lower in invaded plots, and counts of the Green frog Lithobates clamitans were marginally negatively related to mean daily temperature. Our work illustrates how an invasive ecosystem engineer may affect native organisms with which it shares no trophic connection, and suggests that changes in microclimate may be one mechanism by which alien plants affect communities where they invade. [Copyright &y& Elsevier]

Print and online media may reflect changing perceptions about wildlife when viewed in a historical context, as conservation programs bring about increased awareness of declining species. With a proven history of public misunderstanding and persecution, we focused on a nongame and at-risk species, the hellbender salamander (Cryptobranchus alleganiensis). To determine whether public perceptions of hellbenders change according to societal interests over time and to test Shaw's conservation eras, we conducted a content analysis of 288 newspaper articles over the past 153 years of coverage through Conservation Eras, including: Exploitation (1850–1899), Protection (1900–1929), Game Management (1930–1965), Environmental Management (1966–1979), and Conservation Biology (1980–2016). In addition, we examined trends in more recent online media coverage. As measured by article frame (valence values), we detected an increase in positive perceptions about hellbenders in newspapers after 1980, which coincides with the Conservation Biology Era. Many articles published within the Exploitation Era included informative natural history while articles in the Conservation Biology Era included information about the species decline or efforts to conserve and restore populations. Article frames from the Conservation Biology Era were more positive than any other era (X2 = 111.79, p < 0.001). Conservation efforts likely impacted online media coverage (via Google Trends), which increased following the federal listing of Ozark hellbenders and their successful captive rearing by the St. Louis Zoo in 2011. Because knowledge is generated and accessed more readily than ever, and we observed media is representative of societal changes, we anticipate a new era of conservation to follow the digital information age. [ABSTRACT FROM AUTHOR]

Abstract: [(1)] We tested the thermal tolerance of red imported fire ants Solenopsis invicta in two small-scale habitats with different thermal microclimates. [(2)] Knock-down resistance indicated that colonies from an unshaded, warmer site had higher heat tolerance than colonies from a shaded, cooler site. This increased heat tolerance came at no apparent cost to cold tolerance, as ants from both habitats had similar chill-coma recovery times. [(3)] These results show a marked physiological response to localized anthropogenic habitat alterations. [(4)] Quantifying the adaptability of thermal tolerance could be important in understanding the ubiquity of fire ants in the southeastern United States. [Copyright &y& Elsevier]