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Strategic Plan for the North American Breeding Bird Survey: 2006-2010

Executive Summary The mission of the North American Breeding Bird Survey (BBS) is to provide scientifically credible measures of the status and trends of North American bird populations at continental and regional scales to inform biologically sound conservation and management actions. Determining population trends, relative abundance, and distributions of North American avifauna is critical for identifying conservation priorities, determining appropriate conservation actions, and evaluating those actions. The BBS program, jointly coordinated by the U.S. Geological Survey and Environment Canada’s Canadian Wildlife Service, provides the U.S. and Canadian Federal governments, state and provincial agencies, other conservation practitioners, and the general public with science-based avian population trend estimates and other information for regional and national species’ population assessments. Despite the demonstrated value of the BBS for furthering avian conservation across North America, its importance is often underappreciated, and it is underfunded compared with many other government-supported programs that report on status of the environment. Today, BBS resources, adjusted for inflation, are below the amount allocated in the 1970s and are still only sufficient to support two biologists. Yet the number of routes, participants, data, and data requests has quadrupled. Data and information management and delivery requirements and security concerns, non-existent in 1966, impose further demands on BBS resources. In addition, the Mexican expansion of the BBS offers new hope for a truly continental approach to avian conservation, but also brings additional challenges. Meeting the goals of this plan will take cooperation among myriad stakeholders; yet, even with collaboration, most objectives of this plan will be unattainable if BBS program support is not increased. The BBS developed this strategic plan to help set priorities and identify resources required for the program to continue to meet the evolving needs of the conservation community for information on bird population change. By setting clear goals, strategies, and measures of success, this plan provides a cohesive framework and vision for maintenance and development of the BBS. The plan identifies two major goals for the BBS, with a number of strategies and objectives to achieve these goals. Over the next 5 years, progress made in addressing each long-term goal and its associated 5-year strategies and objectives will gage the plan’s success. Specific actions, projected outcomes, and measures of success related to accomplishing these are outlined in Table 1, with a timeline in Table 2. The two main goals for the program, with a summary of the strategies to achieve them, are: Goal 1: Collect scientifically credible measures of the status and trends of North American bird populations at continental and regional scales. The North American Breeding Bird Survey will continue to support North American natural resource conservation through the collection of scientifically credible measures of the status and trends of continental bird populations. While doing this, the BBS will work to improve the science behind the program to better meet its mission and the changing needs of the avian conservation community. In partnership with collaborators, the BBS will address detection probability bias and habitat bias, improve analytical methods, and more fully assess and account for observer quality. Moreover, the BBS will improve the quality and breadth of avian population data through strategic increases in route density and the establishment of a Mexican BBS program. Goal 2: Ensure BBS data and analytical results are widely available and easily accessible for use by the avian conservation and management communities. At the heart of the BBS lies a four-million-record database containing more than 40 years of data on more than 600 bird species. These data are of no value if not well maintained, appropriately analyzed, and widely and easily accessible. The USGS has greatly improved data management and accessibility in recent years. Trend estimates were first made available via the Internet in the mid-1990s, followed closely by the raw data with baseline metadata and standard operating procedures. Nevertheless, numerous enhancements to data management and the usability of BBS results will greatly improve the ability of the BBS to serve avian conservation goals. The BBS needs to ensure that BBS data and results presented on the web site use the best data-management practices and statistical methods, with adequate documentation for users to understand them and any differences between different trend estimates. Moreover, the BBS needs to increase communication with BBS partners and stakeholders to ensure that it continues to meet the avian population status and trends needs of the conservation community and to encourage the development of new products. Working with collaborators, the BBS will develop tools for integrating environmental parameters like habitat change into the analyses, and for integrating BBS data with other avian survey results. In addition, the BBS will continue to improve data and database management through the incorporation of additional data and data fields, such as georeferenced stop locations and more complete metadata for the raw data and results, thus enhancing the uses that can be made of the data.

Circular↗

The history of stream gaging in Ohio

Introduction Streams are a natural resource that can influence economic growth and the development of communities. They supply water for many uses, provide habitat for aquatic plants and animals, and sup-port recreational activities such as boat-ing and fishing. The amount of water (flow) in a stream — either too little or too much — can seriously affect these uses and human life. By using a method called stream gaging , information about the flow in a stream and the fluctuations in that flow can be obtained. n its simplest form, stream gaging may consist of measuring any number of the following stream characteristics: stage (or depth), cross-sectional area, velocity, and (or) flow (or discharge). When the depth and velocity are measured at several points across the stream channel so that the flow (or discharge ) is calculated, a streamflow measurement (or discharge measurement ) is made. By making streamflow measurements at the same site on a stream over a wide range of stages, a relation between stage and discharge can be developed. This relation can be used to provide information on the magnitude and fluctuations of flow on a stream. If long-term or continuous information is needed on a specific site, a stream-gaging station can be established. A stream-gaging station is a site where stage is monitored and recorded and streamflow measurements are made to provide a stage-discharge relation. Ever since the first documented streamflow measurement was made in Ohio — on the Sandusky River — stream-gaging information has been used to minimize the effects of floods and droughts, determine locations for water intakes and wastewater-treatment plants, and provide data for many other uses. Today, stream gaging is a routine activity in managing the State’s water resources.

Ohio↗

A comparison of photograph-interpreted and IfSAR-derived maps of polar bear denning habitat for the 1002 Area of the Arctic National Wildlife Refuge, Alaska

Polar bears ( Ursus maritimus ) in Alaska use the Arctic National Wildlife Refuge (ANWR) for maternal denning. Pregnant bears den in snow banks for more than 3 months in winter during which they give birth to and nurture young. Denning is one of the most vulnerable times in polar bear life history as the family group cannot simply walk away from a disturbance without jeopardizing survival of newly born cubs. The ANWR includes the “1002 Area”, a region recently opened for oil and gas exploration by the U.S. Department of the Interior (DOI). As a part of its mission, the DOI “… protects and manages the Nation's natural resources …” and is therefore responsible for conserving polar bears and encouraging development of energy potential. Because future industrial activities could overlap habitats used by denning polar bears, identifying these habitats can inform the decisions of resource managers tasked to develop resources and protect polar bears. To help inform these efforts, we qualitatively compared the distribution of denning habitat identified by two different methods: previously published habitat from manual interpretation of aerial photographs, and habitat derived by computer interrogation of interferometric synthetic aperture radar (IfSAR) digital terrain models (DTM). Because photograph-interpreted methods depicted denning habitat as a line and IfSAR-derived methods depicted habitat as a polygon, we assessed agreement between the two methods with distance measurements. We found that 77.5 percent of IfSAR-derived denning habitat (79.6 km2 ; 1.2 percent of the 6,837.0 km2 1002 Area) was within 600 m of photograph-interpreted habitat (3,026.9 km), including 53.9 percent within 200 m. This distribution differed from that of randomly distributed points, as only 49.4 percent of these occurred within 600 m of photograph-interpreted habitat, including 18.3 percent within 200 m. Both methods appear to identify the major physiographic features that polar bears might select for denning. IfSAR-derived methods identified habitat at greater frequency beyond major landscape features such as coastal bluffs, river banks and lakeshores, were more likely to identify isolated pockets of putative denning habitat, and were easier to implement than deriving habitat from photograph-interpretive efforts. However, previous research suggests that photograph-interpretation methods may identify denning habitat more correctly than computer interrogation of IfSAR DTMs. Future work should quantify the distribution of IfSAR-derived denning habitat relative to actual landscape features and polar bear maternal dens in the 1002 Area, and investigate the feasibility of habitat identification from finer grained DTMs.

Alaska↗

Evaluation of metal loading to streams near Creede, Colorado, August and September 2000

Decisions about remediation of mine drainage on the watershed scale require an understanding of metal contributions from all sources to be able to choose the best sites for remediation. A hydrologic framework to study metal loading in the Willow Creek watershed, a tributary to the Rio Grande River, was established by conducting a series of tracer-injection studies. Each study used the tracer-dilution method in conjunction with synoptic sampling to determine the spatial distribution of discharge and concentration. Discharge and concentration data were then used to develop mass-loading curves for the metals of interest. The discharge and load profiles (1) identify the principal sources of load to the streams; (2) demonstrate the scale of unsampled, dispersed subsurface inflows; and (3) estimate the amount of natural attenuation. The greatest source of metal loads was from the Nelson Tunnel on West Willow Creek, which contributed 158 kilograms per day of zinc to the stream. Additional loading from other dispersed, subsurface inflows along West Willow Creek added substantial loads, but these were small in comparison to the loads from the Nelson Tunnel. No significant contributions of metal load from potential sources occurred along East Willow Creek. The lack of measurable loading may be a result of previous remedial actions along that stream. The lower Willow Creek section had relatively small contributions of load compared to what had been contributed upstream. This watershed approach provides a detailed snapshot of metal load for the watershed to support remediation decisions and quantifies processes that affect metal transport.

Colorado↗

Hydrology of Haskell Lake and investigation of a groundwater contamination plume, Lac du Flambeau Reservation, Wisconsin

Haskell Lake is a shallow, 89-acre drainage lake in the headwaters of the Squirrel River, on the Lac du Flambeau Reservation in northern Wisconsin. The lake has long been valued by the Lac du Flambeau Band of Lake Superior Chippewa Indians (LDF Tribe) for abundant wild rice and game fish. In recent decades, however, wild rice has mostly disappeared from the lake and the fishery has declined. A petroleum contamination plume discovered in the 1990s in the shallow aquifer upgradient from the northern end of the lake poses a threat to the ecological health of the lake and the aquifer, which is the sole drinking water source for nearby residents and businesses. Understanding of the lake’s hydrology is important to the LDF Tribe as they seek to restore wild rice and maintain the ecological health of the Haskell Lake/Tower Creek watershed. An improved understanding of lithology in the area of the contamination plume, documentation of a contamination pathway from groundwater in the plume source area to Haskell Lake, and an understanding of the plume extent beneath the lake are needed to advance remediation efforts. Evaluation of the fraction of groundwater discharge that is contaminated relative to the overall lake water budget is desired as a first step towards determining the extent of ecological effects from the plume. A cooperative study between the U.S. Geological Survey and the LDF Tribe was initiated to quantify the lake water budget and the sources of water to the lake, to provide a rough estimate of the maximum quantity of groundwater discharge to the lake that may be contaminated, and to improve the conceptual understanding of the plume extent and subsurface materials in the area of contamination. The results of this study can help inform natural resource management of the Haskell Lake/Tower Creek watershed, including planned wild rice restoration and cleanup of the contaminant plume. During 2016–17, field data on lake and groundwater levels, gradients, fluxes, and subsurface lithology were collected using a variety of techniques that ranged from basic measurement of water levels and streamflows to distributed temperature sensing, vertical temperature profiling, and several shallow geophysical methods. The data were used to inform a MODFLOW–NWT model that simulated the contributing groundwatershed, including the water budget for Haskell Lake and Tower Creek using the Lake, Streamflow-Routing, and Unsaturated Zone-Flow Packages. Particle tracking with the MODFLOW solution (using MODPATH 6) was used to improve understanding of the downgradient extent of the contamination plume, estimate groundwater flux through the plume area, and delineate the groundwater contributing area (groundwatershed) for the lake/creek system. Linear uncertainty estimates for model results were computed during model parameter estimation using the software package PEST++. Results indicate groundwater discharge along the perimeter of Haskell Lake, with groundwater accounting for about 22 (± 11.5) percent of the lake water budget. Field data and particle tracking results indicate discharge of the entire contamination plume to Haskell Lake. Although the exact locations where contaminated groundwater enters the lake are unknown, the downgradient extent of the plume beneath Haskell Lake is likely limited to within about 700 feet from the shore. Groundwater flux through the plume accounts for at most about 1.4 percent of total groundwater discharge to Haskell Lake, or about 0.3 percent of the lake water budget. Most groundwater discharging to Haskell Lake and Tower Creek originates as terrestrial recharge. A lesser amount originates in or passes through neighboring lakes, including Buckskin, Crawling Stone, Broken Bow, Tippecanoe, and Jerms Lakes, as well as several unnamed kettles. The average age of simulated groundwater discharge to the lake is about 20 years.

Wisconsin↗

Geohydrology and model analysis for water-supply management in a small area of west-central Kansas

The Ogallala Formation in the intensive-study area, an area of 12 square miles in northeastern Wichita County, west-central Kansas, has had a substantial decrease in saturated thickness since the development of irrigation. The annual water-level decline during 1950-78 ranged from 1.08 to 2.22 feet per year. The hydrologic system was investigated to study methods of conserving the remaining ground water in the intensive-study area. During 1977-78, the average annual ground-water withdrawal was 7,400 acre-feet, and the water-level decline ranged from 0.91 to 5.05 feet. The saturated thickness in 1977 ranged from about 40 to 80 feet, and aquifer storage was about 61,000 acre-feet. Natural recharge is estimated to be 0.28 inch per year. Projections from a digital ground-water flow model were used to indicate the additional water-level decline that might occur from 1978 to 1988 if pumpages in the 480-square-mile model area were one-half, equal to, or double the 1977 pumpage rate. The additional water-level declines in the intensive-study area would range from 5 to 15 feet if pumpages were one-half, 15 to 30 feet if pumpages were equal to, and 25 to 40 feet if pumpages were double the 1977 rate. Projections also were used to indicate the water-level declines if pumpages in the model area were equal to the 1977 rate and if pumpages in the intensive-study area were one-half or double the 1977 rate. Additional water-level declines in the intensive-study area would range from 10 to 20 feet if pumpages were one-half and from 20 to 25 feet if pumpages were doubled. Decreased pumpage in the area could reduce the water-level declines, but continued pumpage in adjacent areas would cause declines to be greater near the edge than near the center. The digital model was more sensitive to changes in pumpage than to changes in hydraulic conductivity, specific yield, and recharge.

Kansas↗

Indicators and protocols for monitoring impacts of formal and informal trails in protected areas

Trails are a common recreation infrastructure in protected areas and their conditions affect the quality of natural resources and visitor experiences. Various trail impact indicators and assessment protocols have been developed in support of monitoring programs, which are often used for management decision-making or as part of visitor capacity management frameworks. This paper reviews common indicators and assessment protocols for three types of trails, surfaced formal trails, unsurfaced formal trails, and informal (visitor-created) trails. Monitoring methods and selected data from three U.S. National Park Service units are presented to illustrate some common trail impact indicators and assessment options.

Journal of Tourism and Leisure Studies↗

Temperature

Stream temperature has direct and indirect effects on stream ecology and is critical in determining both abiotic and biotic system responses across a hierarchy of spatial and temporal scales. Temperature variation is primarily driven by solar radiation, while landscape topography, geology, and stream reach scale ecosystem processes contribute to local variability. Spatiotemporal heterogeneity in freshwater ecosystems influences habitat distributions, physiological functions, and phenology of all aquatic organisms. In this chapter we provide an overview of methods for monitoring stream temperature, characterization of thermal profiles, and modeling approaches to stream temperature prediction. Recent advances in temperature monitoring allow for more comprehensive studies of the underlying processes influencing annual variation of temperatures and how thermal variability may impact aquatic organisms at individual, population, and community based scales. Likewise, the development of spatially explicit predictive models provide a framework for simulating natural and anthropogenic effects on thermal regimes which is integral for sustainable management of freshwater systems.

Book chapter↗

Integrating the effects of salinity on the physiology of the eastern oyster, Crassostrea virginica, in the northern Gulf of Mexico through a Dynamic Energy Budget model

We present a Dynamic Energy Budget (DEB) model for the eastern oyster, Crassostrea virginica , which enables the inclusion of salinity as a third environmental variable, on top of the standard foodr and temperature variables. Salinity changes have various effects on the physiology of oysters, potentially altering filtration and respiration rates, and ultimately impacting growth, reproduction and mortality. We tested different hypotheses as to how to include these effects in a DEB model for C. virginica . Specifically, we tested two potential mechanisms to explain changes in oyster shell growth (cm), tissue dry weight (g) and gonad dry weight (g) when salinity moves away from the ideal range: 1) a negative effect on filtration rate and 2) an additional somatic maintenance cost. Comparative simulations of shell growth, dry tissue biomass and dry gonad weight in two monitored sites in coastal Louisiana experiencing salinity from 0 to 28 were statistically analyzed to determine the best hypothesis. Model parameters were estimated through the covariation method, using literature data and a set of specifically designed ecophysiological experiments. The model was validated through independent field studies in estuaries along the northern Gulf of Mexico. Our results suggest that salinity impacts C. virginica ’s energy budget predominantly through effects on filtration rate. With an overwhelming number of environmental factors impacting organisms, and increasing exposure to novel and extreme conditions, the mechanistic nature of the DEB model with its ability to incorporate more than the standard food and temperature variables provides a powerful tool to verify hypotheses and predict individual organism performance across a range of conditions.

Ecological Modelling↗

Mg isotope constraints on soil pore-fluid chemistry: Evidence from Santa Cruz, California

Mg isotope ratios ( 26 Mg/ 24 Mg) are reported in soil pore-fluids, rain and seawater, grass and smectite from a 90 kyr old soil, developed on an uplifted marine terrace from Santa Cruz, California. Rain water has an invariant 26 Mg/ 24 Mg ratio (expressed as δ26 Mg> δ26 Mg ) at −0.79 ± 0.05‰, identical to seawater δ26 Mg> δ26 Mg . Detrital smectite (from the base of the soil profile, and therefore unweathered) has a δ26Mg"> δ26Mg value of 0.11‰, potentially enriched in 26 Mg by up to 0.3‰ compared to the bulk silicate Earth Mg isotope composition (although within the range of all terrestrial silicates). The soil pore-waters show a continuous profile with depth for δ26 Mg> δ26 Mg , ranging from −0.99‰ near the surface to −0.43‰ at the base of the profile. Shallow pore-waters (<1 m) have δ26 Mg> δ26 Mg values that are similar to, or slightly lower than the rain waters. This implies that the degree of biological cycling of Mg in the pore-waters is relatively small and is quantified as <32%, calculated using the average Mg isotope enrichment factor between grass and rain ( δ26 Mggrass- δ26 Mgrain> δ26 Mggrass- δ26 Mgrain ) of 0.21‰. The deep pore-waters (1–15 m deep) have δ26 Mg> δ26 Mg values that are intermediate between the smectite and rain, ranging from −0.76‰ to −0.43‰, and show a similar trend with depth compared to Sr isotope ratios. The similarity between Sr and Mg isotope ratios confirms that the Mg in the pore-waters can be explained by a mixture between rain and smectite derived Mg, despite the fact that Mg and Sr concentrations may be buffered by the exchangeable reservoir. However, whilst Sr isotope ratios in the pore-waters span almost the complete range between mineral and rain inputs, Mg isotopes compositions are much closer to the rain inputs. If Mg and Sr isotope ratios are controlled uniquely by a mixture, the data can be used to estimate the mineral weathering inputs to the pore-waters, by correcting for the rain inputs. This isotopic correction is compared to the commonly used chloride correction for precipitation inputs. A consistent interpretation is only possible if Mg isotope ratios are fractionated either by the precipitation of a secondary Mg bearing phase, not detected by conventional methods, or selective leaching of 24 Mg from smectite. There is therefore dual control on the Mg isotopic composition of the pore-waters, mixing of two inputs with distinct isotopic compositions, modified by fractionation. The data provide (1) further evidence for Mg isotope fractionation at the surface of the Earth and (2) the first field evidence of Mg isotope fractionation during uptake by natural plants. The coherent behaviour of Mg isotope ratios in soil environments is encouraging for the development of Mg isotope ratios as a quantitative tracer of both weathering inputs of Mg to waters, and the physicochemical processes that cycle Mg, a major cation linked to the carbon cycle, during continental weathering.

California↗

Naegleria fowleri detected in Grand Teton National Park hot springs

The free-living thermophilic amoeba Naegleria fowleri ( N. fowleri ) causes the highly fatal disease primary amoebic meningoencephalitis. The environmental conditions that are favorable to the growth and proliferation of N. fowleri are not well-defined, especially in northern regions of the United States. In this study, we used culture-based methods and multiple molecular approaches to detect and analyze N. fowleri and other Naegleria spp. in water, sediment, and biofilm samples from five hot spring sites in Grand Teton National Park, Wyoming, U.S.A. These results provide the first detections of N. fowleri in Grand Teton National Park and provide new insights into the distribution of pathogenic N. fowleri and other nonpathogenic Naegleria spp. in natural thermal water systems in northern latitudes.

Wyoming↗

Estimating mortality of Lake Sturgeon in the Lake Winnebago system using traditional age-based approaches and capture–recapture models

Objective The Lake Winnebago system in Wisconsin supports a popular winter spear fishery for Lake Sturgeon Acipenser fulvescens . Setting harvest caps for this fishery relies on estimating instantaneous natural mortality rate ( M ), which can be done using age-based approaches or capture–recapture models that incorporate recoveries of fish with passive integrated transponder (PIT) tags or detections of fish with acoustic transmitters. Our objectives were to determine (1) if recent estimates of exploitation ( u ) have exceeded the 5% harvest cap, (2) if M and total mortality rates are similar among estimation methods that rely on age estimates or capture–recapture methods, and (3) if potential differences in mortality estimates would affect harvest caps. Methods Harvest of PIT-tagged fish was used to evaluate u from 2010 to 2019. Catch curves incorporating corrected fin ray ages were used to estimate total mortality and M for fish collected from 2010 to 2019. Capture–recapture models were used to estimate annual survival and M from detections of fish with acoustic transmitters from 2007 to 2019 and recoveries of PIT-tagged fish from 1999 to 2020. Mortality estimates were used to calculate and compare sex-specific harvest caps among estimation methods. Results Observed u did not exceed 5% for either sex between 2010 and 2019. Estimates of M varied among methods (males: M = 0.001–0.134; females: M = 0.001–0.131), with PIT-based models consistently providing the lowest and telemetry-based models providing the highest estimates. Simulations indicated that female u has limited potential to exceed 5% if M from fin ray ages or telemetry is used to set harvest caps, while PIT-based simulations showed no indication of cap exceedance. Conclusions Harvest management practices in the Lake Winnebago system appear to have kept Lake Sturgeon exploitation below the 5% harvest cap from 2010 to 2019. Capture–recapture models relying on PIT tags appear to provide the most precise approach for setting harvest caps for this fishery.

Wisconsin↗

Using plant invasions to compare occurrence- and abundance-based calculations of biotic homogenisation: Are results complementary or contradictory?

Aim Beta diversity quantifies the similarity of ecological assemblages. Its increase, known as biotic homogenisation, can be a consequence of biological invasions. However, species occurrence (presence/absence) and abundance-based analyses can produce contradictory assessments of the magnitude and direction of changes in beta diversity. Previous work indicates these contradictions should be less frequent in nature than in theory, but a growing number of empirical studies report discrepancies between occurrence- and abundance-based approaches. Understanding if these discrepancies represent a few isolated cases or are systematic across a diversity of ecosystems would allow us to better understand the general patterns, mechanisms and impacts of biotic homogenisation. Location United States. Time Period 1963–2020. Major Taxa Studied Vascular plants. Methods We used a dataset of more than 70,000 vegetation survey plots to assess differences in biotic homogenisation with and without invasion using both occurrence- and abundance-based metrics of beta diversity. We estimated taxonomic biotic homogenisation by comparing beta diversity of invaded and uninvaded plots with both classes of metrics and investigated the characteristics of the non-native species pool that influenced the likelihood that these metrics disagree. Results In 78% of plot comparisons, occurrence- and abundance-based calculations agreed in direction, and the two metrics were generally well correlated. Our empirical results are consistent with previous theory. Discrepancies between the metrics were more likely when the same non-native species was at high cover at both plots compared for beta diversity, and when these plots were spatially distant. Main Conclusions In about 20% of cases, our calculations revealed differences in direction (homogenisation vs. differentiation) when comparing occurrence- and abundance-based metrics, indicating that the metrics are not interchangeable, especially when distances between plots are high and invader diversity is low. When data permit, combining the two approaches can offer insights into the role of invasions and extirpations in driving biotic homogenisation/differentiation.

Global Ecology and Biogeography↗

Palynology in coal systems analysis-The key to floras, climate, and stratigraphy of coal-forming environments

Palynology can be effectively used in coal systems analysis to understand the nature of ancient coal-forming peat mires. Pollen and spores preserved in coal effectively reveal the floristic composition of mires, which differed substantially through geologic time, and contribute to determination of depositional environment and paleo- climate. Such applications are most effective when integrated with paleobotanical and coal-petrographic data. Examples of previous studies of Miocene, Carboniferous, and Paleogene coal beds illustrate the methods and results. Palynological age determinations and correlations of deposits are also important in coal systems analysis to establish stratigraphic setting. Application to studies of coalbed methane generation shows potential because certain kinds of pollen are associated with gas-prone lithotypes. ??2005 Geological Society of America.

Special Paper of the Geological Society of America↗

An integrated approach to the Taxonomic identification of prehistoric shell ornaments

Shell beads appear to have been one of the earliest examples of personal adornments. Marine shells identified far from the shore evidence long-distance transport and imply networks of exchange and negotiation. However, worked beads lose taxonomic clues to identification, and this may be compounded by taphonomic alteration. Consequently, the significance of this key early artefact may be underestimated. We report the use of bulk amino acid composition of the stable intra-crystalline proteins preserved in shell biominerals and the application of pattern recognition methods to a large dataset (777 samples) to demonstrate that taxonomic identification can be achieved at genus level. Amino acid analyses are fast (<2 hours per sample) and micro-destructive (sample size <2 mg). Their integration with non-destructive techniques provides a valuable and affordable tool, which can be used by archaeologists and museum curators to gain insight into early exploitation of natural resources by humans. Here we combine amino acid analyses, macro- and microstructural observations (by light microscopy and scanning electron microscopy) and Raman spectroscopy to try to identify the raw material used for beads discovered at the Early Bronze Age site of Great Cornard (UK). Our results show that at least two shell taxa were used and we hypothesise that these were sourced locally.

PLoS ONE↗

Electrofishing mark-recapture and depletion methodologies evoke behavioral and physiological changes in cutthroat trout

We examined the behavioral and physiological responses of wild and hatchery-reared cutthroat trout Oncorhynchus clarki subjected to a single electroshock, electroshock plus marking, and multiple electroshocks in natural and artificial streams. In a natural stream, cutthroat trout released after capture by electrofishing and marking showed distinct behavioral changes: fish immediately sought cover, remained relatively inactive, did not feed, and were easily approached by a diver. An average of 3–4 h was required for 50% of the fish to return to a seemingly normal mode of behavior, although responses varied widely among collection sites. Using the depletion method, we observed little change in normal behavior offish remaining in the stream section (i.e., uncaptured fish) after successive passes with electrofishing gear. In an artificial stream, hatchery-reared and wild cutthroat trout immediately decreased their rates of feeding and aggression after they were electroshocked and marked. Hatchery fish generally recovered in 2–3 h; wild fish required at least 24 h to recover. Analysis of feeding and aggression data by hierarchical rank revealed no distinct recovery trends among hatchery fish of different ranks; among wild cutthroat trout, however, socially dominant fish seemed to recover faster than intermediate and subordinate fish. Physiological indicators of stress (plasma cortisol and blood lactic acid) increased significantly in cutthroat trout subjected to electroshock plus marking or single or multiple electroshocks. As judged by the magnitude of the greatest change in cortisol and lactate, multiple electroshocks elicited the most severe stress response; however, plasma concentrations of both substances had returned to unstressed control levels by 6 h after treatment. It was evident that electrofishing and the procedures involved with estimating fish population size elicited a general stress response that was manifested not only physiologically but also behaviorally. These responses may affect the accuracy of population size estimates by violating key assumptions of the methods, especially the assumption of equal catchability offish.

Transactions of the American Fisheries Society↗

Water-quality monitoring for a pilot piling removal field evaluation, Coal Creek Slough, Washington, 2008-09

Significant Findings Water and sediment quality monitoring was conducted before and after the removal of a piling field located in Coal Creek Slough near Longview, Washington. Passive chemical samplers and continuous water-quality monitoring instruments were deployed at the piling removal site, Coal Creek Slough Site 1 (CCS1), and at a comparison site, Coal Creek Slough Site 2 (CCS2), before (2008) and after (2009) piling removal. Surface and subsurface (core) sediment samples were collected before and after piling removal and were analyzed for grain size, organic carbon content, and chemicals of concern. Significant findings from this study include: * Phenanthrene was the only compound detected in wood piling samples analyzed for a large suite of semivolatile organic compounds and polycyclic aromatic hydrocarbons (PAHs). Metals potentially associated with wood treatment were detected in the wood piling samples at low concentrations. * Organic carbon was slightly lower in core samples from CCS1 in pre-removal (2008) and post-removal (2009) samples than in surface samples from both sites in both years. * Grain-size class distributions were relatively uniform between sites and years. * Thirty-four out of 110 chemicals of concern were detected in sediments. Eight of those detected were anthropogenic waste indicator (AWI) compounds, 18 were PAHs, 4 were sterols, and 4 were metals potentially associated with wood treatment. * Nearly all reported concentrations of chemicals of concern in sediments are qualified as estimates, primarily due to interferences in extracts resulting from complex sample matrices. Indole, perylene, and fluoranthene are reported without qualification for some of the samples, and the metals are reported without qualification for all samples. * The highest frequency of detection of chemicals of concern was seen in the pre-removal surface samples at both sites. * AWI compounds were detected less frequently and at lower concentrations during the post-removal sampling compared to the pre-removal sampling. * Several PAHs were detected at relatively high concentrations in core samples, likely indicating historical sources. * Most commonly detected PAHs in sediments were 2,6-dimethylnaphthalene, fluoranthene, perylene, and pyrene. * Most commonly detected AWIs in sediments were 3-methyl-1h-indole (skatol), acetophenone, indole, phenol, and paracresol. * Sedimentary concentrations of perylene exceeded available sediment quality guidelines. Perylene is widespread in the environment and has large potential natural sources in addition to its anthropogenic sources. * Concentrations of metals did not exceed sediment quality guidelines. * Multiple organochlorine pesticides, both banned and currently used, were detected at each site using passive samplers. * Commonly detected pesticides included hexachlorobenzene, pentachloroanisole (a degradation product of pentachlorophenol), diazinon, cis-chlordane, endosulfan, DDD, and endosulfan sulfate. * PBDE concentrations detected in passive sampler extracts were less than the method detection limit at all sites with the exception of PBDE-99, detected at a concentration less than the reporting limit. * The fragrance galaxolide was detected at a concentration greater than the method detection limit. * Common PAHs, such as phenanthrene, fluoranthene, and pyrene, were detected in every passive sampler. * Dissolved oxygen concentration was slightly higher at site CCS1 compared to site CCS2 in both years. * Overall, there was no systematic increase in chemicals of concern at the restoration site during post-removal monitoring compared to conditions during pre-removal monitoring. Any immediate, short-duration effects of piling removal on water quality could not be determined because monitoring was not conducted during the removal.

Open-File Report↗

Kelp forest monitoring at Naval Base Ventura County, San Nicolas Island, California: Fall 2018 and Spring 2019, fifth annual report

Introduction Kelp forests and rocky reefs are among the most recognized marine ecosystems and provide the primary habitat for several species of fishes, invertebrates, and algal assemblages (Stephens and others, 2006). In addition, kelp forests have been shown to be important carbon dioxide sinks (Wilmers and others, 2012) and are an important source of nearshore marine primary production (Duggins and others, 1989). These highly dynamic ecosystems are extremely variable, and both top-down and bottom-up ecological controls drive this rich trophic environment. Giant kelp ( Macrocystis pyrifera ) forests and the species that inhabit these ecosystems are influenced by several environmental conditions, such as wave exposure, water temperature, water clarity, bottom depth and composition, species composition, and the density of kelp and other algal assemblages (Schiel and Foster, 2015). However, in addition to “normal” variability, kelp forests can undergo extreme regime shifts from kelp canopy forested areas to barrens characterized by high densities of urchins and encrusting coralline algae (Harrold and Reed, 1985). San Nicolas Island (SNI), outermost of the California Channel Islands, is home to a diverse group of terrestrial and marine organisms and includes kelp bed and rocky reef habitats ( fig. 1 ). The SNI kelp forests not only provide food and shelter for fishes and invertebrates within the habitat, but also they support higher trophic level consumers such as marine birds and several marine mammal species including the southern sea otter ( Enhydra lutris nereis) , a major predator on sea urchins and other marine invertebrates. Owing to concern about the vulnerability of the California population, the U.S. Fish and Wildlife Service (USFWS) translocated 140 southern sea otters from the central California coast to SNI between 1987 and 1990. Although only approximately 14 translocated otters are thought to have remained at SNI (U.S. Fish and Wildlife Service, 2012), their population at the island has increased and is currently greater than 120 individuals (Hatfield and others, 2019). Sea otters are a natural part of the kelp forest ecosystem, but their presence has implications for community dynamics as they repopulate a region from which they were extirpated in the 19th century. At SNI, sea otters have been concentrated mostly around the west end of the island, with some use of the south side and very little, but expanding, use of the northeast side. An ecosystem shift from urchin dominated to kelp dominated, that occurred at a site at the west end of the island in the early 2000s, though initiated by sea urchin disease, was likely facilitated to some degree by sea otter foraging (Kenner and Tinker, 2018). These ecosystems also are the target of many fisheries, including urchin and lobster. Urchin fisheries, which target the larger red sea urchin, may release the smaller but more mobile purple sea urchin from competitive control (Dayton and others, 1998). Lobster fisheries may release purple sea urchins from predatory control (Lafferty, 2004). Owing to the distance from the mainland, however, SNI kelp forests and reefs have been somewhat protected from the degree of harvest and other anthropogenic impacts experienced by the southern California mainland. Invasive species are another issue, and there are a few invasive subtidal macroalgae of concern in southern California waters. Although the brown alga Sargassum muticum has been established at the island for decades, S. horneri has only recently been seen at SNI and, so far, the invasive kelp Undaria pinnatifida and the green alga Caulerpa taxifolia have not been observed there. Sargassum horneri , in particular, has demonstrated a capability to outcompete native kelps at some of the other Channel Islands but it is unclear what indirect effects it may have on community structure (Marks and others, 2015). Because the surrounding kelp forests fall within the management boundary of the SNI Integrated Natural Resources Management Plan (INRMP; U.S. Navy, 2015), USGS works with the Navy to provide surveys of this ecologically important ecosystem that inform natural resource managers of trends in the population abundance of particular species. In addition, long-term surveys allow for an understanding of potential changes in species diversity and community composition as a result of trophic or other interactions. The U.S. Geological Survey (USGS) implemented a kelp forest monitoring program for the U.S. Navy at San Nicolas Island in 2014, building on sites and methods established by USFWS scientists in 1980 ( appendix 1 ). This report focuses on data collected during sampling expeditions to these sites in fall 2018 (October 2–5) and spring 2019 (April 3–6). Together they will be herein referred to as year 5 because, although the trips were made in different calendar years, they were approximately 6 months apart and were conducted under the fifth year of this contract. The previous sampling year (fall 2017 and spring 2018) is referred to as year 4. The year 5 data are compared with data collected during eight trips from fall 2014 through spring 2018. Differences in counts between these expeditions can result from seasonal factors, stochastic variation, or sampling error, but temporal comparison can reveal population trends. Where appropriate, long-term data collected during the 33 years prior to the implementation of these slightly revised protocols will be presented in order to lend some context to the observations reported here. Genus and species names used in this report are those currently recognized as valid in the Integrated Taxonomic Information System (ITIS.gov). Upon first use, the name recognized as valid by the World Register of Marine Species (WoRMS; marinespecies.org) is shown in brackets if different. The exception is Sargassum horneri which does not show up in any discernable form in ITIS.gov.

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