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The largest North American Silphidae, the American burying beetle (ABB), Nicrophorus americanus Olivier, has been extirpated from ∼90% of its historic range and is federally threatened. Two distinct populations in the Southern (Oklahoma and Arkansas) and North-Central United States (Nebraska and South Dakota) persist at the western edge of the ABB's former range. In Nebraska, the western limits of occurrence are associated with Merritt Reservoir and linked irrigation canals. ABBs are also found at the nearby hand-planted McKelvie National Forest. While habitat alteration and fragmentation are likely the primary reasons for ABB decline, few studies have examined their response to human habitat modifications unrelated to urbanization or agricultural conversion. Through five-day sampling periods with carrion-baited pitfall traps, ABB were captured and recorded in June and August from 2015 to 2017 at Merritt Reservoir and McKelvie National Forest in Cherry County, Nebraska. Traps were placed in transects (N = 4) at each location with reservoir traps set at the shoreline, transition, and upland habitats and forest traps set in the prairie, transition zone, and pine forest. At Merritt Reservoir, 651 ABB were captured, with significantly more collected at the shoreline. Concurrently, 23 ABB were captured at McKelvie Forest, with more ABB found within the forest compared to nearby prairie. These findings support previous suggestions that the western distribution of ABB is limited by moisture. Further investigation may indicate that reliable soil moisture associated with altered habitats in Nebraska could support ABB and potentially allow western range expansion. [ABSTRACT FROM AUTHOR]

Western alligator snapping turtles, Macrochelys temminckii, have experienced population declines throughout most of their distribution. The present study is the first to systematically sample aquatic habitats of western Tennessee to assess the status and distribution of this species within the state. At the 65 sites sampled, we captured 22 individual alligator snapping turtles from 4 sites, including 1 site where juveniles had been reintroduced more than a decade prior. We conclude that M. temminckii occurs at very low densities in western Tennessee, likely due to historical habitat modification (e.g., channelizing rivers or ditching). [ABSTRACT FROM AUTHOR]

Mudpuppies (Necturus maculosus) are secretive, fully aquatic salamanders with a range that spans much of the eastern United States and Canada including the Great Lakes region. Although this species was once abundant, there have been widespread declines due to habitat loss and modification, pollution, lampricide use, and overcollection. We compared environmental DNA (eDNA) and trapping surveys conducted from 2014 to 2016 to determine Mudpuppy occupancy along the St. Clair-Detroit River System, where this indicator species could be a gauge for success of ongoing restoration. Mudpuppy eDNA was detected at all sites with positive trapping records, as well as one site where individuals have not been trapped previously. Sites with shoreline restoration had the highest occupancy estimates, whereas deep-water restoration did not affect Mudpuppy occupancy. Additionally, eDNA surveys resulted in higher detection probability than setline and minnow trap survey methods, illustrating the benefit of using eDNA to detect secretive species. This study demonstrates the success of restoration efforts in increasing the occupancy of an indicator species and can be used as a template for other restoration initiatives. [ABSTRACT FROM AUTHOR]

The Pascagoula map turtle (Graptemys gibbonsi) and Pearl map turtle (Graptemys pearlensis) were first separated from the Alabama map turtle (Graptemys pulchra) in 1992 under the former name and subsequently recognized as 2 separate species in 2010. The possibility that they should be listed under the Endangered Species Act was raised 7 yrs after separation from G. pulchra, when basking surveys showed that at most sites they were considerably less abundant than 2 sympatric congeners listed as threatened: the Pearl River drainage's ringed sawback (Graptemys oculifera, listed in 1986) and the Pascagoula River drainage's yellow-blotched sawback (Graptemys flavimaculata, listed in 1991). Historical data also indicated that the sympatric species pairs may once have been more similar in abundance. Now, more than 2 decades later, G. gibbonsi and G. pearlensis are candidates for listing. From 2015 to 2018, we surveyed basking turtles in point counts and in jon boat and canoe surveys and conducted trapping at several sites to ascertain the status of the 2 candidate species. Data were also combined with similar data collected between 2006 and 2014. Despite their similarity morphologically and in their basic ecology, 3 important differences are pertinent to the question of whether the 2 candidate species should be federally protected. First, their river systems are geomorphically very different. The medium-size to large tributary streams that the 2 species inhabit are a considerably more prominent feature of the Pascagoula drainage than the Pearl drainage and may insulate populations from potential threats on the main stems. Second, G. gibbonsi inhabited 35% more stream reach, had 22% higher catch per unit effort, and were recorded at 44% higher numbers in point counts and 3% higher numbers in basking density surveys than G. pearlensis. Coarse-scale estimates of each species' global populations suggest that G. gibbonsi is ∼ 1.56 times as abundant as G. pearlensis overall. Third, the reasons for the listing of each species' sympatric sawback congener are very different: G. oculifera of the Pearl drainage was listed primarily due to existing and imminent but as-yet-unrealized habitat modification, while G. flavimaculata of the Pascagoula drainage was listed primarily due to perceived low populations, particularly in upper portions of the drainage, and concerns regarding water quality. We conclude that G. pearlensis warrants conservation protection via a listing as threatened, while G. gibbonsi should be listed either as threatened or as threatened by similarity of appearance. For G. gibbonsi, the former option would recognize a long-term historical decline in its relative abundance suggested by trapping data from the 1950s through 1970s, while the latter would recognize its less imperiled status and protect it from the pet trade while focusing recovery efforts on G. pearlensis. [ABSTRACT FROM AUTHOR]

Hartwell, S.I. and Fukuyama, A.K., 2015. The effects of sieve size on benthic community composition analysis. Sediment samples were collected from the deep portion of Kachemak Bay, Alaska, for chemical analysis, toxicity testing, and infaunal community assessment as part of a larger Cook Inlet project. The benthos samples were sieved through nested 1.0- and 0.5-mm screens to allow a comparison of the relative efficacy of the two techniques. The community was highly diverse at all sampled locations (Shannon-Weiner Index > 3). Abundance was dominated by a relatively small number of species. A significantly higher number of individuals and species were retained on the 0.5-mm screen. Sieving the benthic organisms with a 1.0-mm sieve introduced biases in the data relative to the 0.5-mm screen, including calculations such as diversity and other parameters such as feeding guild distributions and benthic indices. Using a 0.5-mm mesh sieve did increase sample analysis costs and resulted in a larger number of individual organisms that were not identified to species. [ABSTRACT FROM AUTHOR]

The diamondback terrapin ( Malaclemys terrapin) is a species of conservation concern that has experienced noticeable declines throughout its range. Mark-recapture studies have been conducted on terrapins at Kiawah Island, South Carolina, since 1983, and during the early 1990s, this population began to decline. Our objectives were to evaluate current spatial and temporal variation in survivorship and compare current estimates of survivorship with those calculated from 1983 to 1999 in a previous study. We used an 11-year data set (2003 to 2013) in a capture-mark-recapture analysis to estimate the survivorship of terrapins in 5 creeks. Among creeks, annual survivorship estimates ranged from 61% to 82% with no difference between the sexes. Survivorship was lower than that documented for this population in the early 1990s. Recent anthropogenic habitat modification, such as the construction of docks, roads, and housing developments, as well as activities such as crab-trapping, likely play a role in low annual survivorship. Results from this long-term study are essential for understanding terrapin population status and can inform conservation and coastal ecosystem management. [ABSTRACT FROM AUTHOR]

Louisiana's 2012 Master Plan for a sustainable coast was designed to minimize economic damage from storm surges and to maximize wetland habitat for fish and wildlife. Selecting projects for inclusion in the master plan depended partly on models that simulated the effects of management options on environmental factors that control habitat quality for fish and wildlife. We used 13 models to predict the effects of the master plan on habitat quality for fish and wildlife in coastal Louisiana. Habitat quality was predicted to change more for the Neotropical songbirds and seven other modeled species losing habitat quality with the status quo (-37%) than it was predicted to increase for five modeled species gaining habitat quality with the status quo (+18%). The master plan was predicted to slow or negate all changes associated with the status quo. All of the modeled fish and wildlife belong to people of the state of Louisiana, people living in countries bordering the Gulf of Mexico, and to people throughout the Americas. Thus, declining fish and wildlife habitat quality in Louisiana probably will cause market and nonmarket losses, which although concentrated in Louisiana, will extend across the Americas. As funding for Louisiana's master plan is pursued, it is important to consider that almost all of the causes for net wetland losses in Louisiana are external to the owners of these wetlands but that the fish and wildlife that use these wetlands belong to and benefit people throughout the Americas. [ABSTRACT FROM AUTHOR]

Sporobolus virginicus (C. Linnaeus) K. Kunth is a warm temperate, subtropical, and pantropical rhizomatous grass. It is an important species in foredunes, primary dunes, interdunal depressions, salt marshes, brackish marshes, and on the margins of salt pans where it is often a dominant species. Sporobolus virginicus is a euhalophyte that tolerates soluble salts ranging from 3 to 94 parts per thousand, and where the pH varies from 6 to 8.8. This species is freeze sensitive at -2.5oC with no hardening capacity. Also known as seashore dropseed, seedlings are sensitive to tidal inundation, but established plants are not affected by waterlogged conditions. The species is important for controlling beach erosion and for stabilizing sandy substrates. Stands of S. virginicus provide food for livestock and wildlife. Herein, we present a review of the biology of this important species. [ABSTRACT FROM AUTHOR]

Sixteen sites in China where Ceratopteris pteridoides occurs based on historical records and/or from observations were surveyed during preliminary field surveys. Eight previously recorded populations were found to have been extirpated. Decline in natural populations of C. pteridoides has resulted from the destruction or complete loss of its primary habitat. Analysis of 17 parameters of water quality indicated that differences in pH and dissolved oxygen might be principal factors determining the distribution and occurrence of C. pteridoides. The sites of the extirpated populations had higher water pH values than those of the sites of the extant populations [P < 0.05). The value of dissolved oxygen concentration at the sites of the extirpated populations was lower than at the sites of the extant populations (P < 0.05). The degeneration of primary habitats, a decline in the area of wetland coverage and deterioration of water quality caused by human activities are identified as the likely key factors responsible for the reduction in C. pteridoides populations. Because the habitat and population characteristics of eleven remaining populations were different, different sites should adopt different conservation methods as appropriate. Some small populations could be conserved by establishing conservation areas; other relatively large populations could be conserved by establishing nature reserves. [ABSTRACT FROM AUTHOR]

NORIEGA, R.; SCHLACHER, T.A., and SMEUNINX, B., 2012. Reductions in ghost crab populations reflect urbanization of beaches and dunes. Coastal management is being challenged to develop and implement measures that safeguard the ecological values of beach and dune ecosystems, particularly in urban settings. Monitoring the efficacy of such interventions requires reliable indicators of ecological change. Here, we tested the efficacy of ghost crabs (Genus Ocypode) to reflect changes in the degree of human beach use and habitat modifications. This was done across six beaches that differed in the degree of 'urbanization' on Australia's Gold Coast, which ranks amongst the country's most intensively developed coastal areas. Population densities of crabs closely match the levels of beach use and human disturbance: Beaches with fewer visitors are less likely to be raked mechanically, thereby, supporting significantly higher numbers of crabs than do beaches with more visitors, which are cleaned more frequently. These spatial differences were consistent across eight surveys. Beaches backed by wider dunes that were more densely vegetated were better habitats than were the beaches with severely modified dunes. From a management perspective, our findings emphasize the critical role of maintaining-and possibly restoring-all remnant dune habitats. A premium on conserving dunes should be complemented by continued visitor management and new initiatives to develop and use more ecologically sensitive beach cleaning techniques. [ABSTRACT FROM AUTHOR]

The Loxahatchee River, a 500 km2 watershed on the southeast Florida coast, is a barrier-impounded drowned river valley experiencing rapid urbanization during the past 50 years. The estuary is currently composed of a sandy central basin with bifurcating forks accumulating organic-rich muddy sands. The Northwest Fork drains natural forest, residential, and agricultural catchments and has a much larger bayhead delta than the channelized Southwest Fork, which is only 50 years old and diverts much of the flow from the Northwest Fork. Sediment accumulation rates within muddy sand deposits are about 2-3 mm a-1, commensurate within error of the current rate of local sea-level rise. Previously established Holocene accumulation rates are close to relative sea-level rise, implying that sediment accumulation is in equilibrium with the creation of accommodation space. The main anthropogenic influences have been changes in surface sediment texture corresponding to dredging-induced modification of tidal currents and a localized>threefold increase in sediment accumulation rate supplied by sources local to the estuary. Late Holocene sedimentation has been episodic, and lithofacies vary from bioturbated transgressive sands at depth to peat and laminated fine-grained sediments then back to mottled muddy sands in the uppermost strata. This facies transition is attributed to a change of water column stratification conditions caused by decreased tidal flushing in the estuary possibly brought about by variation in sea level or episodic inlet closure by littoral sand transport. The magnitude of the anthropogenic changes in sedimentation is roughly equal with natural changes in lithofacies formation. [ABSTRACT FROM AUTHOR]

The article focuses on the results of the survey of the odonate species and their habitats at the Lostwood National Wildlife Refuge (LNWR) in North Dakota. The species of Odonata were identified and explored on its diverse specie composition among its habitat. The study of these odonate species can assess the diversity of ecology and the quality of the ecosystem. The survey also helped in the identification of extinct species and create contingency plans to conserve them. Odonate species' diversity tend to decrease during the winter season causing negative effects to the flight of adult species.

Sea level rise has been identified as a possible factor contributing to marsh loss in Jamaica Bay, New York. However, Jamaica Bay has also experienced increases in tidal ranges throughout as a consequence of natural and engineering modifications that occurred in the bay during the first half of the twentieth century. The increases in the elevations of high tides are of the same order as the increase in regional sea level that occurred since the early 1900s. Marsh inundation in the bay is thus greater than noted to date and greater than that in adjacent bays where tidal ranges have been more stable. Changes in tidal hydrodynamics may be one more factor to consider in the list of potential causes of marsh loss in Jamaica Bay. [ABSTRACT FROM AUTHOR]