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USGS1993

Ground-water quality of the Upper Floridan Aquifer near an abandoned manufactured gas plant in Albany, Georgia

Manufactured gas plants produced gas for heating and lighting in the United States from as early as 1816 into the 1960's. By-products including, but not limited to, oil residues and tar, were generated during the gas-manufacturing process. Organic compounds (hydrocarbons) were detected in water in the upper water-bearing zone of the Upper Floridan aquifer near an abandoned manufactured gas plant (MGP) in Albany, Georgia, during an earlier investigation in 1990. Chemical analyses of ground-water samples collected from five existing monitoring wells in 1991 verify the presence of hydrocarbons and metals in the upper water-beating zone of the Upper Floridan aquifer. One well was drilled into the lower water-beating zone of the Upper Floridan aquifer in 1991 for water-quality sampling and water-level monitoring. Analyses of ground water sampled from this well did not show evidence of benzene, toluene, xylene, napthalene, acenaphthlene, or other related compounds detected in the upper water-bearing zone in the study area. Low concentrations of tetrachloroethane, trichloromethane, and l,2-cisdichloroethene were detected in a water sample from the deeper well; however, these compounds were not detected in the upper water-bearing zone in the study area. Inorganic constituent concentrations also were substantially lower in the deeper well. Overall, ground water sampled from the lower water-bearing zone had lower specific conductance and alkalinity; and lower concentrations of dissolved solids, iron, and manganese compared to ground water sampled from the upper water-bearing zone. Water levels for the upper and lower water-bearing zones were similar throughout the study period.

Georgia↗

USGS1993

Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated 43 to 420 micrograms per liter. Sediment elutriate samples were toxic to Ceriodaphnia dubta, Pimephales promelas, Photobacterium phosphoreum, and Salenastrum capricornulum.

Water-Resources Investigations Report↗

USGS1993

Hydrogeology, ground-water quality, and potential for water-supply contamination near an abandoned wood-preserving plant site at Jackson, Tennessee

Hydrogeologic and ground-water-quality data were collected near an abandoned wood-preserving plant site at Jackson, Tennessee to determine the extent and magnitude of ground-water contamination in offsite areas and to assess the potential for contamination of nearby water-supply wells. New methods were used to collect ground-water samples from the alluvial aquifer at six offsite stations at depths of less than about 40 feet below land surface. In addition, 36 offsite wells were installed at these stations to collect samples from the alluvial aquifer and to depths of about 150 feet in the deeper Fort Pillow aquifer. Ground-water samples collected by the new methods and from the 36 offsite wells were analyzed for selected volatile and semi-volatile compounds. The samples collected from the 36 wells also were analyzed for major and trace inorganic constituents. Naphthalene and some volatile organic compounds were detected at low concentrations in samples from both the alluvial aquifer and the Fort Pillow aquifer. To assess the potential for water-supply contamination from the site, four water-supply wells to the east (upgradient) and three wells to the west (down- gradient) of the abandoned plant site were sampled. These samples were analyzed for the same analytes as the samples from the 36 wells. Although volatile organic compounds and elevated concentrations of trace and major inorganic constituents were measured in samples from some wells east of the site, no organic compounds associated with the wood- preserving process were detected. No contaminants from the site were detected in samples from wells west of the site.

Water-Resources Investigations Report↗

USGS1994

Particulate, colloidal, and dissolved-phase associations of plutonium and americium in a water sample from well 1587 at the Rocky Flats Plant, Colorado

In November 1991, the initial phase of a study to determine the dominant aqueous phases that control the transport of plutonium (Pu), americium (Am), and uranium (U) in surface and groundwater at the Rocky Flats Plant was undertaken by the U.S. Geological Survey. By use of the techniques of stirred-cell spiral-flow filtration and crossflow ultrafiltration, particles of three size fractions were collected from a 60-liter sample of water from well 1587 at the Rocky Flats Plant. These samples and corresponding filtrate samples were analyzed for Pu and Am. As calculated from the analysis of filtrates, 65 percent of Pu 239 and 240 activity in the sample was associated with particulate and largest colloidal size fractions. Particulate (22 percent) and colloidal (43 percent) fractions were determined to have significant activities in relation to whole-water Pu activity. Am and Pu 238 activities were too low to be analyzed. Examination and analyses of the particulate and colloidal phases indicated the presence of mineral species (iron oxyhydroxides and clay minerals) and natural organic matter that can facilitate the transport of actinides in ground water. High concentrations of the transition metals copper and zinc in the smallest colloid fractions strongly indicate a potential for organic complexation of metals, and potentially of actinides, in this size fraction.

Colorado↗

USGS1993

Element concentrations in growth rings of trees near an abandoned wood-preserving plant site at Jackson, Tennessee

Multielement analysis was performed on individual annual rings of trees growing at and near an abandoned wood-preserving plant site in Jackson, Tennessee, that operated from the early 1930's until 1981. Numerous organic compounds associated with the wood-preserving process have been detected in soils, ground water, and surface water within much of the site. Tree-ring investigations were conducted prior to investigations of ground water downgradient from the site to determine if trees preserved an areal and temporal record of contaminant movement into offsite areas. Increment cores were collected from trees on the abandoned plant site, in downgradient areas west and south of the site, and at two locations presumably unaffected by contamination from the site. Multielement analysis by proton-induced X-ray emission was performed on 5 to 15 individual growth rings from each of 34 trees that ranged in age from about 5 to 50 years. Concentrations of 16 elements were evaluated by analyzing average concentrations within the 1987, 1989, and 1990 rings of all trees; analyzing element-concentration trends along entire core radii; and analyzing element correlations between and among trees. Concentrations of some nutrients and trace metals were elevated in the outermost sapwood rings of some trees that grow south and southwest of the most contaminated part of the site; small trees on the main part of the site and larger trees to the west generally contained fewer rings with elevated concentrations, particularly of trace metals. Concentrations of several elements elevated in tree rings also were elevated in water samples collected from the reach of a stream that flows near the southwestern part of the site. Multielement analysis of each ring of a willow growing along the southern boundary of the site detected extremely large concentrations of chromium, nickel, and iron in rings that formed in 1986 and thereafter. Relative increases in the concentrations of these elements also were detected in a silver maple growing next to the willow, but not in another silver maple growing 150 meters farther to the west. An oak growing in the southwestern part of the study area contained large concentrations of calcium and several trace elements, and some trees south of the abandoned site contained large concentrations of phosphorus or potassium. Concentrations of trace metals and nutrients in some trees may be related to wood-preserving activities at the site and possibly to remedial efforts conducted during the early to mid 1980's.However, the possibility cannot be discounted that large concentrations of some elements are from sources other than the wood-preserving facility, or in part from flooding of the South Fork Forked Deer River.

Water-Resources Investigations Report↗

USGS1999

Aquatic macroinvertebrates collected at Ravenna Army Ammunition Plant, Portage and Trumbull Counties, Ohio, 1998

The results of a survey of macroinvertebrate communities in the Ravenna Army Ammunition Plant, were used as an indicator of disturbance in streams flowing through or near the training areas at the Plant. The data were interpreted using the Invertebrate Community Index (ICI), a multiple-metric index developed by the Ohio Environmental Protection Agency and based on the structural and functional characteristics of the macroinvertebrate community. Quantitative samples of the macroinvertebrate were collected for ICI determination from three streams South Fork Eagle Creek, Sand Creek, and Hinkley Creek flowing through the study area. These samples were collected using Hester-Dendy type artificial substrate samplers, which were placed in the streams during a 6-week sampling period, June 2 through July 15, 1998. A qualitative- dipnet sample from the natural substrates also was collected at each station on July 15, 1998, the last day of the sampling period. The macroinvertebrate communities at all three stations met the criterion designated for warmwater habitat aquatic life use, and communities at two of the three stations exceeded the criterion. The ICI scores were 42 at South Fork Eagle Creek, 50 at Sand Creek, and 48 at Hinkley Creek. The density of macroinvertebrates at South Fork Eagle Creek was 1,245 per square foot and represented 38 distinct taxa. The density at Sand Creek was 246 per square foot and represented 29 distinct taxa. The density at Hinkley Creek was 864 per square foot and represented 36 distinct taxa. Qualitative samples were also collected at 21 other sites using a D-framed dipnet. The qualitative sites encompassed three main environments: stream, pond, and swamp-wetland. All available habitat types in each environment were sampled until no new taxa were evident during coarse examination. The highest number of taxa were collected from the streams. The total number of taxa collected in streams ranged from 25 to 76; the mean was 60 and median 64. The total taxa collected from ponds ranged from 32 to 60; the mean was 42 and median 41. The total taxa collected from swamp-wetland areas ranged from 6 to 30; the mean was 20 and median 23. The results are listed in phylogenetic order in this report and establish baseline data for future studies.

Ohio↗

USGS1967

Geology and ground water of the Savannah River Plant and vicinity, South Carolina

The area described in this report covers approximately 2,600 square miles in west-central South Carolina and includes the site of the Savannah River Plant, a major production facility of the U.S. Atomic Energy Commission. The climate, surface drainage, and land forms of the study area are typical of the southern part of the Atlantic Coastal Plain. Precipitation is normally abundant and fairly evenly distributed throughout the year, and the mean annual temperature is moderately warm (64?F). The major streams that drain the area (the Savannah, Salkehatchie, and Edisto Rivers) have low gradients and flow in a southeasterly direction toward the Atlantic Ocean. Surface features of the area include narrow, flat-bottomed, steep-sided valleys and broad gently rolling interfluvial areas. Those parts of the Coastal Plain included within the report area can be subdivided into the Aiken Plateau, the Congaree Sandhills, and the Coastal Terraces. The area is underlain by a sequence of unconsolidated and partly consolidated sediments of Late Cretaceous, Tertiary, and Quaternary age. The unconsolidated sediments were deposited unconformably on a basement of igneous and metamorphic rocks of Precambrian and Paleozoic age and sedimentary rocks of Triassic age. The basement rocks are similar to the granite-diorite complex of the Charlotte Belt, the metamorphosed rocks of the Carolina Slate Belt, and the consolidated sediments of the Newark Group. The unconsolidated sediments strike about N. 60 ? E. and dip 6-20 feet per mile to the southeast. They form a wedge-shaped mass that increases in thickness toward the southeast to slightly more than 1,200 feet in the vicinity of Allendale, S.C., on the southeast or downdip side of the study area. The oldest or lowermost unconsolidated sedimentary unit, the Tuscaloosa Formation of Late Cretaceous age, is overlain in the subsurface by beds that are also probably Late Cretaceous in age and that herein are named the Ellenton Formation. The Upper Cretaceous deposits are, in turn, overlain by the, McBean Formation and the Congaree(?) Formation of middle Eocene age, the Barnwell Formation of late Eocene age, the Hawthorn Formation of early and middle Miocene age, and by fluvial and marine(?) terrace deposits of Pliocene(?), Pleistocene, and Recent age. In the mapped area, the Congaree(?) Formation includes undifferentiated rocks (mostly Congaree and Barnwell Formations and some Mcbean outliers). (See map explanation.) Structurally, the Upper Cretaceous sediments are overlapped to the northwest by Tertiary deposits. A preliminary geologic map of the general area is included in the report. The principal aquifer in the area is composed of the beds of medium to coarse sand and gravel contained in the Tuscaloosa and Ellenton Formations. Subordinate aquifers include deposits of sand and limestone of Tertiary and Quaternary age. The ground water in the principal aquifer occurs under water-table conditions in the outcrop area of the Tuscaloosa Formation in the northern and western parts of the study area, but it is under artesian pressure downdip in the southern and eastern parts of the study area. Contours drawn on the piezometric surface of the water in the principal aquifer indicate that water is recharged to the aquifer mainly by leakage through the overlying Tertiary formations. Likewise, the piezometric contours show that the outcrop area of the Tuscaloosa Formation functions chiefly as an area of discharge. Doubtless, water is also discharged from the aquifer by moving downdip to areas near the coast where the prevailing hydraulic gradient may favor the upward leakage of water through the upper confining beds. The hydraulic properties of the principal aquifer were determined by a series of pumping tests. The results indicate that the aquifer is highly productive and could supply 15 million gallons per day in the vicinity of the Savannah River Plant without exceeding the available drawdown.

South Carolina↗

USGS2009

A proposed origin for fossilized Pennsylvanian plant cuticles by pyrite oxidation (Sydney Coalfield, Nova Scotia, Canada)

Fossilized cuticles, though rare in the roof rocks of coal seam in the younger part of the Pennsylvanian Sydney Coalfield, Nova Scotia, represent nearly all of the major plant groups. Selected for investigation, by methods of Fourier transform infrared spectroscopy (FTIR) and elemental analysis, are fossilized cuticles (FCs) and cuticles extracted from compressions by Schulze's process (CCs) of Alethopteris ambigua. These investigations are supplemented by FTIR analysis of FCs and CCs of Cordaites principalis, and a cuticle-fossilized medullosalean(?) axis. The purpose of this study is threefold: (1) to try to determine biochemical discriminators between FCs and CCs of the same species using semi-quantitative FTIR techniques; (2) to assess the effects chemical treatments have, particularly Schulze's process, on functional groups; and most importantly (3) to study the primary origin of FCs. Results are equivocal in respect to (1); (2) after Schulze's treatment aliphatic moieties tend to be reduced relative to oxygenated groups, and some aliphatic chains may be shortened; and (3) a primary chemical model is proposed. The model is based on a variety of geological observations, including stratal distribution, clay and pyrite mineralogies associated with FCs and compressions, and regional geological structure. The model presupposes compression-cuticle fossilization under anoxic conditions for late authigenic deposition of sub-micron-sized pyrite on the compressions. Rock joints subsequently provided conduits for oxygen-enriched ground-water circulation to initiate in situ pyritic oxidation that produced sulfuric acid for macerating compressions, with resultant loss of vitrinite, but with preservation of cuticles as FCs. The timing of the process remains undetermined, though it is assumed to be late to post-diagenetic. Although FCs represent a pathway of organic matter transformation (pomd) distinct from other plant-fossilization processes, global applicability of the chemical models remains to be tested. CCs and FCs are inferred endpoints on a spectrum of pomd which complicates assessing origin of in-between transformations (partially macerated cuticles). FCs index highly acidic levels that existed locally in the roof rocks.

Bulletin of Geosciences↗

USGS2009

An emerging crisis across northern prairie refuges: Prevalence of invasive plants and a plan for adaptive management

In the northern Great Plains, native prairies managed by the U.S. Fish and Wildlife Service (Service) can be pivotal in conservation of North America's biological diversity. From 2002 to 2006, we surveyed 7,338 belt transects to assess the general composition of mixed-grass and tallgrass prairie vegetation across five "complexes" (i.e., administrative groupings) of national wildlife refuges managed by the Service in North Dakota and South Dakota. Native grasses and forbs were common (mean frequency of occurrence 47%-54%) on two complexes but uncommon (4%-13%) on two others. Conversely, an introduced species of grass, smooth brome (Bromus inermis), accounted for 45% to 49% of vegetation on two complexes and another species, Kentucky bluegrass (Poa pratensis) accounted for 27% to 36% of the vegetation on three of the complexes. Our data confirm prior suspicions of widespread invasion by introduced species of plants on Service-owned tracts of native prairie, changes that likely stem in part from a common management history of little or no disturbance (e.g., defoliation by grazing or fire). However, variability in the degree and type of invasion among prairie tracts suggests that knowledge of underlying causes (e.g., edaphic or climatic factors, management histories) could help managers more effectively restore prairies. We describe an adaptive management approach to acquire such knowledge while progressing with restoration. More specifically, we propose to use data from inventories of plant communities on Service-owned prairies to design and implement, as experiments, optimal restoration strategies. We will then monitor these experiments and use the results to refine future strategies. This comprehensive, process-oriented approach should yield reliable and robust recommendations for restoration and maintenance of native prairies in the northern Great Plains. 2009 by the Board of Regents of the University of Wisconsin System.

Ecological Restoration↗

USGS2021

Watershed and estuarine controls both influence plant community and tree growth changes in tidal freshwater forested wetlands along two U.S. mid-Atlantic rivers

The tidal freshwater zone near the estuarine head-of-tide is potentially sensitive to both sea-level rise and associated salinity increases as well as changing watershed inputs of freshwater and nutrients. We evaluated the vegetation response of tidal freshwater forested wetlands (TFFW) to changes in nontidal river versus estuarine controls along the longitudinal gradient of the Mattaponi and Pamunkey rivers in the Mid-Atlantic USA. The gradient included nontidal freshwater floodplain (NT) and upper tidal (UT), lower tidal (LT), and stressed tidal forest transitioning to marsh (ST) TFFW habitats on both rivers. Plot-based vegetation sampling and dendrochronology were employed to examine: (1) downriver shifts in plant community composition and the structure of canopy trees, understory trees/saplings/shrubs and herbs, tree basal-area increment (BAI) and (2) interannual variability in BAI from 2015 dating back as far as 1969 in relation to long-term river and estuary monitoring data. With greater tidal influence downstream, tree species dominance shifted, live basal area generally decreased, long-term mean BAI of individual trees decreased, woody stem mortality increased, and live herbaceous vegetative cover and richness increased. Acer rubrum , Fagus grandifolia , Ilex opaca , and Fraxinus pennsylvanica dominated NT and UT sites, with F. pennsylvanica and Nyssa sylvatica increasingly dominating at more downstream tidal sites. Annual tree BAI growth was positively affected by nontidal river flow at NT and UT sites which were closer to the head-of-tide, positively influenced by small salinity increases at LT and ST sites further downstream, and positively influenced by estuarine water level throughout the gradient; nutrient influence was site specific with both positive and negative influences. The counterintuitive finding of salinity increasing tree growth at sites with low BAI is likely due to either competitive growth release from neighboring tree death or enhanced soil nutrient availability that may temporarily mitigate the negative effects of low-level salinization and sea-level increases on living TFFW canopy trees, even as overall plant community conversion to tidal marsh progresses.

Virginia↗

USGS2026

Advancing ecosystem recovery with diverse species plantings in tropical forest restoration

Tropical forest restoration has increased in the past decades, with possible advancements given the UN declaration of the “Decade of Ecosystem Restoration”. However, robust assessments to compare ecosystem functions among restored forest stages are essential. We evaluated 13 actively restored forest stands ranging from 3 to 21 years of age and compared measures of forest biodiversity, structure, and ecosystem function to four 70+ year old “reference” stands that serve as restoration “targets” in the study region of the Premontane wet forest of Costa Rica. The restored stands were planted with an average of 13 tree species on abandoned pastures that were fallow for at least two years. Sixteen tree-stand attributes and six ecosystem function estimates were assessed, including: annual biomass (C) accumulation, N-fixation potential, threatened species conservation, and the provision of avian frugivore forage, insect habitat, and insect pollination. Using Principal Component Analysis, linear modeling, and Mahalanobis distance analyses, we learned that planting a diversity of tree species sets the stage for forest recovery at early restoration ages, with an inflection point at 15 years towards older reference forest characteristics and functions. Given that all restoration ages provided tree diversity and some level of ecosystem functions, the value of all restored stands in the landscape is notable. The assessment methods are easily employed, thereby providing an accessible tool to restoration practitioners.

Monteverde↗

USGS2014

Native plant recovery in study plots after fennel (Foeniculum vulgare) control on Santa Cruz Island

Santa Cruz Island is the largest of the California Channel Islands and supports a diverse and unique flora which includes 9 federally listed species. Sheep, cattle, and pigs, introduced to the island in the mid-1800s, disturbed the soil, browsed native vegetation, and facilitated the spread of exotic invasive plants. Recent removal of introduced herbivores on the island led to the release of invasive fennel ( Foeniculum vulgare ), which expanded to become the dominant vegetation in some areas and has impeded the recovery of some native plant communities. In 2007, Channel Islands National Park initiated a program to control fennel using triclopyr on the eastern 10% of the island. We established replicate paired plots (seeded and nonseeded) at Scorpion Anchorage and Smugglers Cove, where notably dense fennel infestations (>10% cover) occurred, to evaluate the effectiveness of native seed augmentation following fennel removal. Five years after fennel removal, vegetative cover increased as litter and bare ground cover decreased significantly ( P < 0.0001) on both plot types. Vegetation cover of both native and other (nonfennel) exotic species increased at Scorpion Anchorage in both seeded and nonseeded plots. At Smugglers Cove, exotic cover decreased significantly ( P = 0.0001) as native cover comprised of Eriogonum arborescens and Leptosyne gigantea increased significantly ( P < 0.0001) in seeded plots only. Nonseeded plots at Smugglers Cove were dominated by exotic annual grasses, primarily Avena barbata. The data indicate that seeding with appropriate native seed is a critical step in restoration following fennel control in areas where the native seed bank is depauperate.

California↗

USGS2006

Evaluating plant invasions from both habitat and species perspectives

We present an approach to quantitatively assess nonnative plant invasions at landscape scales from both habitat and species perspectives. Our case study included 34 nonnative species found in 142 plots (0.1 ha) in 14 vegetation types within the Grand Staircase–Escalante National Monument, Utah. A plot invasion index, based on nonnative species richness and cover, showed that only 16 of 142 plots were heavily invaded. A species invasive index, based on frequency, cover, and number of vegetation types invaded, showed that only 7 of 34 plant species were highly invasive. Multiple regressions using habitat characteristics (moisture index, elevation, soil P, native species richness, maximum crust development class, bare ground, and rock) explained 60% of variation in nonnative species richness and 46% of variation in nonnative species cover. Three mesic habitats (aspen, wet meadow, and perennial riparian types) were particularly invaded (31 of 34 nonnative species studied were found in these types). Species-specific logistic regression models for the 7 most invasive species correctly predicted occurrence 89% of the time on average (from 80% for Bromus tectorum , a habitat generalist, to 93% for Tamarix spp., a habitat specialist). Even with such a modest sampling intensity (<0.1% of the landscape), this multiscale sampling scheme was effective at evaluating habitat vulnerability to invasion and the occurrence of the 7 most invasive nonnative species. This approach could be applied in other natural areas to develop strategies to document invasive species and invaded habitats.

Utah↗

USGS2011

An adaptive decision framework for the conservation of a threatened plant

Mead's milkweed Asclepias meadii , a long-lived perennial herb of tallgrass prairie and glade communities of the central United States, is a species designated as threatened under the U.S. Endangered Species Act. Challenges to its successful management include the facts that much about its life history is unknown, its age at reproductive maturity is very advanced, certain life stages are practically unobservable, its productivity is responsive to unpredictable environmental events, and most of the known populations occur on private lands unprotected by any legal conservation instrument. One critical source of biological uncertainty is the degree to which fire promotes growth and reproductive response in the plant. To aid in its management, we developed a prototype population-level state-dependent decision-making framework that explicitly accounts for this uncertainty and for uncertainties related to stochastic environmental effects and vital rates. To parameterize the decision model, we used estimates found in the literature, and we analyzed data from a long-term monitoring program where fates of individual plants were observed through time. We demonstrate that different optimal courses of action are followed according to how one believes that fire influences reproductive response, and we show that the action taken for certain population states is informative for resolving uncertainty about competing beliefs regarding the effect of fire. We advocate the use of a model-predictive approach for the management of rare populations, particularly when management uncertainty is profound. Over time, an adaptive management approach should reduce uncertainty and improve management performance as predictions of management outcome generated under competing models are continually informed and updated by monitoring data.

Journal of Fish and Wildlife Management↗

USGS1993

Lesser scaup forage on zebra mussels at Cook nuclear plant, Michigan

Nineteen of 21 Lesser Scaup (Aythya affinis) entrained while foraging at the water intake structures of Cook Nuclear Plant, Bridgman, Michigan had consumed zebra mussels (Dreissena polymorpha). The average number of zebra mussels in the upper gastrointestinal tract was 260; maximum number was 987. Migrating Lesser Scaup found this new food source during the first winter following settlement of zebra mussels on the water intake structures of the power plant.

Journal of Field Ornithology↗

USGS1992

First flowering dates and flowering periods of prairie plants at Woodworth, North Dakota

We recorded flowering events for 97 species of prairie plants for 2-6 years near Woodworth, ND. Earliest and latest flower initiation dates varied by year. Temperature seemed much more important than precipitation in influencing phenology of species that bloom from late March through May, but no strong climatic effect was evident for plants that bloom later in the growing season.

Prairie Naturalist↗

USGS1990

Plant communities of Santa Rosa Island, Channel Islands National Park

A survey of the plant communities on Santa Rosa Island, Channel Islands National Park, was conducted from January through July 1988. Vegetation data were collected at 296 sites using a releve technique. The plant communities described include: grassland, coastal marsh, caliche scrub, coastal sage scrub, lupine scrub, baccharis scrub, coastal bluff scrub, coastal dune scrub, mixed chaparral, mixed woodland, torrey pine woodland, closed-cone pine woodland, island oak woodland, riparian woodland, and riparian herbaceous vegetation. The areal extent of each community was mapper on USGS 7.5' topographic maps, and digitized for GIS manipulation.

Technical Report↗

USGS2004

Native bees and plant pollination

Bees are important pollinators, but evidence suggests that numbers of some species are declining. Decreases have been documented in the honey bee, Apis mellifera (which was introduced to North America), but there are no monitoring programs for the vast majority of native species, so we cannot be sure about the extent of this problem. Recent efforts to develop standardized protocols for bee sampling will help us collect the data needed to assess trends in bee populations. Unfortunately, diversity of bee life cycles and phenologies, and the large number of rare species, make it difficult to assess trends in bee faunas. Changes in bee populations can affect plant reproduction, which can influence plant population density and cover, thus potentially modifying horizontal and vertical structure of a community, microclimate near the ground, patterns of nitrogen deposition, etc. These potential effects of changes in pollination patterns have not been assessed in natural communities. Effects of management actions on bees and other pollinators should be considered in conservation planning.

Rhode Island Naturalist↗