Geology topics

Carrie J. Blakeslee

Publications and source records attributed to Carrie J. Blakeslee.

16 recordsLinked to original sources

USGS2020

A weight-of-evidence approach for defining thermal sensitivity in a federally endangered species

1. Managing for threatened and endangered species under changing environmental conditions is a challenge faced by resource managers worldwide. Lack of basic knowledge of the biology and habitat requirements of these species can contribute to this difficulty, but is confounded by the limitations of working with rare (i.e. few individuals) species or unrefined methods for evaluating stress. 2. A weight of evidence approach was used to evaluate the thermal biology of the federally endangered dwarf wedgemussel ( Alasmidonta heterodon ), utilizing cumulative results from multiple experimental assessments, co-occurring species, and their host fish to begin defining thermal limits and optimal conditions for the species. 3. Results suggest that dwarf wedgemussel and its host fish are thermally sensitive species compared to other Atlantic-slope mussels, with lower critical thermal maximum and selection of reduced temperatures during choice experiments. 4. Physiological studies resulted in lack of statistical significance primarily due to low power which was a function of sample size, one unavoidable problem when studying rare species. Given these limitations, thermal choice and CTM may be more useful endpoints than physiological processes such as clearance and respiration rates when dealing with sample size limitations. 5. These results suggest that management strategies that avoid exposing dwarf wedgemussel and its thermally sensitive host fish to extreme temperatures could be important for species conservation.

New Jersey, Pennsylvania↗

USGS2019

The effects of seasonal temperature and photoperiod manipulation on reproduction in the eastern elliptio Elliptio complanata

The eastern elliptio Elliptio complanata is a species of freshwater mussel common to streams and rivers of the Atlantic Coast. Egg fertilization, larval brooding, and glochidial release are reported to occur within a period of several weeks during early to midsummer. In this study, mussels were exposed to manipulated photoperiod and water temperatures to prolong the availability of glochidia for use in artificial propagation and research. Brooding mussels were collected from Pine Creek, Tioga County, PA, in late December and were housed in groups subjected to one of four environmental treatments: natural temperature and photoperiod, 6-wk delay in natural conditions, 12-wk delay in natural conditions, and natural temperature and photoperiod with a winter low of 10°C. Reproductive activity was monitored for 1 y. Mussels subjected to natural conditions released mature glochidia between 16°C and 19°C with a photoperiod of 15 h of light. Temperature and photoperiod delays of 6 and 12 wk delayed reproduction proportional to the treatment, and constant 10°C winter low temperatures slightly shifted the timing of glochidial release. Survival during the study was high (96%–100%). Data indicate that the seasonal availability of E. complanata glochidia can be extended 3-fold using photoperiod and temperature manipulation.

Journal of Shellfish Research↗

USGS2018

Reestablishing a host–affiliate relationship: Migratory fish reintroduction increases native mussel recruitment

Co‐extirpation among host–affiliate species is thought to be a leading cause of biodiversity loss worldwide. Freshwater mussels (Unionida) are at risk globally and face many threats to survival, including limited access to viable host fish required to complete their life history. We examine the relationship between the common eastern elliptio mussel ( Elliptio complanata ) and its migratory host fish the American eel ( Anguilla rostrata ), whose distribution in the Chesapeake Bay watershed is limited, in part, by dams. We examined population demographics of E. complanata across locations in the Chesapeake Bay watershed, primarily in the Susquehanna River in the absence of American eels, and conducted experimental restocking of eels to assess potential impacts on mussel recruitment. Compared to surveys completed ~20 yr prior, E. complanata could be experiencing declines at several historically abundant sites. These sites also had extremely limited evidence of recruitment. Restoration of host fish improved recruitment, but results were not equivalent between stocking sites, indicating that host reintroduction alone may not be fully effective in reestablishing mussel populations. One site where eels were introduced (Pine Creek, Tioga County, Pennsylvania, USA) experienced an increase from 0 juveniles found during quantitative surveys prior to eel stocking to 151 (21% of individuals collected during quantitative surveys) E. complanata juveniles found four years after stocking. A second site (Buffalo Creek, Union County, Pennsylvania) experienced a more moderate increase from 2 to 7 juveniles found during 2010 and 2014 quantitative surveys, respectively. Continued examination of other potential interacting factors affecting recruitment, including water quality or habitat conditions, is necessary to target favorable sites for successful restoration.

Maryland, Pennsylvania↗

USGS2018

Freshwater mussel survey for the Columbia Dam removal, Paulins Kill, New Jersey

Semi-quantitative mussel surveys, conducted by the U.S. Geological Survey and the Delaware Riverkeeper Network in cooperation with The Nature Conservancy, were completed in the vicinity of the Columbia Dam, on the Paulins Kill, New Jersey, in August 2017 in order to document the mussel species composition and relative abundance prior to removal of the dam. Surveys were conducted from the Brugler Road Bridge downriver approximately 2,000 meters (m) to the Columbia Dam and downriver from the dam about 300 m to 75 m upriver from the confluence of the Paulins Kill with the Delaware River. Sixteen sections (average length=175 m) were surveyed by personnel snorkeling or SCUBA diving; 13 sections were upriver from the dam, and 3 were downriver from the dam. Mussels, as they were encountered by surveyors, were removed from the sediment, immediately identified to species, and replaced in their original collection locations. Habitat data were collected for each surveyed section. Upriver and downriver from the dam, river margins with dense vegetation were examined for mussels by personnel using snorkels in transects (approximately 25 meters) perpendicular to river flow every 50 m on both sides of the river. Only two species were found upriver from the dam, and those were present in relatively low numbers. Catch per unit effort is reported here within parentheses as the average across upriver sections in number of mussels per person hour of survey time: 42 Elliptio complanata (2.6) and 1 Pyganodon cataracta (0.1) were found upriver from the dam. No mussels were found in the dense vegetation either upriver or downriver of the dam by surveyors using snorkels. Significantly higher species richness and mussel catch per unit effort were found downriver from the dam than upriver, including 106 E. complanta (32.5), 27 Utterbackiana implicata (8.2), 1 Alasmidonta undulata (0.4), 2 Lampsilis cariosa (0.5), 6 Lampsilis radiata (2.1), 4 P. cataracta (1.1), and 1 Strophitus undulatus (0.4). The average habitat assessment score did not differ upriver and downriver from the dam.

New Jersey↗

USGS2018

Freshwater mussel salvage and relocation at the Pond Eddy Bridge, Delaware River, New York and Pennsylvania

In a study conducted by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Transportation, freshwater mussels were salvaged and relocated from the anticipated zone of impact for the Pond Eddy Bridge construction project in New York and Pennsylvania. Five 25-meter (m) by 25-m cells along the Pennsylvania bank of the Delaware River were sampled in three generally straight-line passes by four surveyors wearing snorkel gear for a total of 180 survey minutes per cell. All mussels encountered were collected and identified to species. A subset of individuals was marked with shellfish tags, weighed, and measured prior to relocation upstream from the zone of impact. A total of 3,434 mussels, including 3,393 Elliptio complanata (eastern elliptio mussels), 39 Anodonta implicata (alewife floaters), 1 Strophitus undulatus (creeper), and 1 Pyganodon cataracta (eastern floater), were salvaged and relocated. All non-eastern elliptio species were georeferenced using a high-resolution global positioning system unit; a subset of tagged eastern elliptio was placed in transects between georeferenced points. These mussels will be monitored to assess the effects of translocation on mortality and body condition at 1 month, 1 year, and 2 years.

New York, Pennsylvania↗

USGS2018

Changes in freshwater mussel communities linked to legacy pollution in the Lower Delaware River

Freshwater mussels are among the most-imperiled organisms worldwide, although they provide a variety of important functions in the streams and rivers they inhabit. Among Atlantic-slope rivers, the Delaware River is known for its freshwater mussel diversity and biomass; however, limited data are available on the freshwater mussel fauna in the lower, non-tidal portion of the river. This section of the Delaware River has experienced decades of water-quality degradation from both industrial and municipal sources, primarily as a function of one of its major tributaries, the Lehigh River. We completed semi-quantitative snorkel surveys in 53.5 of the 121 km of the river to document mussel community composition and the continued impacts from pollution (particularly inputs from the Lehigh River) on mussel fauna. We detected changes in mussel catch per unit effort (CPUE) below the confluence of the Lehigh River, with significant declines in the dominant species Elliptio complanata (Eastern Elliptio) as we moved downstream from its confluence—CPUE dropped from 179 to 21 mussels/h. Patterns in mussel distribution around the Lehigh confluence matched chemical signatures of Lehigh water input. Specifically, Eastern Elliptio CPUE declined more quickly moving downstream on the Pennsylvania bank, where Lehigh River water input was more concentrated compared to the New Jersey bank. A definitive causal link remains to be established between the Lehigh River and the dramatic shifts in mussel community composition, warranting continued investigation as it relates to mussel conservation and restoration in the basin.

Lower Delaware River↗

USGS2018

The effects of rearing temperature on American glass eels

American eels are declining throughout their range requiring a better understanding of physiological requirements of all life stages and optimal conditions for laboratory rearing and aquaculture. American glass eels (Anguilla rostrata) were housed for 3 weeks at 14˚C, 18˚C, 22˚C, or 26˚C to determine optimal juvenile rearing temperature in the laboratory. All treatments exhibited weight gain over the course of the study except the 14˚C treatment; however, there were only marginal differences in final weight between the 18˚C and 14˚C treatments and no differences in length. Variation in length and weight generally increased as temperature increased with significant differences in the standard error of weight between 14˚C and the 22˚C and 26˚C treatments and between 18˚C and 26˚C. Mortality was significantly greater than expected by chance at 26˚C (7 deaths) and no mortality was observed at 14˚C. Body condition (based on the residuals from the weight-length relationships), conversely, was lowest in the 14˚C treatment. Considering all response variables, optimal laboratory rearing conditions were observed between 18˚C - 22˚C. Within a week of experimentation, evidence of gas bubble disease was observed and by completion noted in all treatments except at 14˚C, likely as a function of decreased gas solubility at warmer temperatures. Levels of total gas pressure (103% - 108%) and Δp (28 - 54 mm Hg) values may account for the gas bubbles observed.

Agricultural Sciences↗

USGS2017

RNA sequencing analysis of transcriptional change in the freshwater mussel Elliptio complanata after environmentally relevant sodium chloride exposure

To identify potential biomarkers of salt stress in a freshwater sentinel species, we examined transcriptional responses of the common mussel Elliptio complanata to controlled sodium chloride (NaCl) exposures. Ribonucleic acid sequencing (RNA-Seq) of mantle tissue identified 481 transcripts differentially expressed in adult mussels exposed to 2 ppt NaCl (1.2 ppt chloride) for 7 d, of which 290 had nonoverlapping intervals. Differentially expressed gene categories included ion and transmembrane transport, oxidoreductase activity, maintenance of protein folding, and amino acid metabolism. The rate-limiting enzyme for synthesis of taurine, an amino acid frequently linked to osmotic stress in aquatic species, was upregulated, as was the transmembrane ion pump sodium/potassium adenosine 5′-triphosphatase. These patterns confirm a primary transcriptional response to the experimental dose, albeit likely overlapping with nonspecific secondary stress responses. Substantial involvement of the heat shock protein 70 chaperone family and the water-transporting aquaporin family was not detected, however, in contrast to some studies in other bivalves. A subset of the most significantly regulated genes was confirmed by quantitative polymerase chain reaction in an independent sample. Cluster analysis showed separation of mussels exposed to 2 ppt NaCl from control mussels in multivariate space, but mussels exposed to 1 ppt NaCl were largely indistinguishable from controls. Transcriptome-scale analysis of salt exposure under laboratory conditions efficiently identified candidate biomarkers for further functional analysis and field validation

Environmental Toxicology and Chemistry↗

USGS2016

Donor life stage influences juvenile American eel Anguilla rostrata attraction to conspecific chemical cues

The present study investigated the potential role of conspecific chemical cues in inland juvenile American eel Anguilla rostrata migrations by assessing glass eel and 1 year old elver affinities to elver washings, and elver affinity to adult yellow eel washings. In two-choice maze assays, glass eels were attracted to elver washings, but elvers were neither attracted to nor repulsed by multiple concentrations of elver washings or to yellow eel washings. These results suggest that A. rostrata responses to chemical cues may be life-stage dependent and that glass eels moving inland may use the odour of the previous year class as information to guide migration. The role of chemical cues and olfaction in eel migrations warrants further investigation as a potential restoration tool.

Journal of Fish Biology↗

USGS2016

Evaluating methods to establish habitat suitability criteria: A case study in the upper Delaware River Basin, USA

Defining habitat suitability criteria (HSC) of aquatic biota can be a key component to environmental flow science. HSC can be developed through numerous methods; however, few studies have evaluated the consistency of HSC developed by different methodologies. We directly compared HSC for depth and velocity developed by the Delphi method (expert opinion) and by two primary literature meta-analyses (literature-derived range and interquartile range) to assess whether these independent methods produce analogous criteria for multiple species (rainbow trout, brown trout, American shad, and shallow fast guild) and life stages. We further evaluated how these two independently developed HSC affect calculations of habitat availability under three alternative reservoir management scenarios in the upper Delaware River at a mesohabitat (main channel, stream margins, and flood plain), reach, and basin scale. In general, literature-derived HSC fell within the range of the Delphi HSC, with highest congruence for velocity habitat. Habitat area predicted using the Delphi HSC fell between the habitat area predicted using two literature-derived HSC, both at the basin and the site scale. Predicted habitat increased in shallow regions (stream margins and flood plain) using literature-derived HSC while Delphi-derived HSC predicted increased channel habitat. HSC generally favoured the same reservoir management scenario; however, no favoured reservoir management scenario was the most common outcome when applying the literature range HSC. The differences found in this study lend insight into how different methodologies can shape HSC and their consequences for predicted habitat and water management decisions. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

New York, Pennsylvania↗

USGS2015

Thiaminase activity in native freshwater mussels

Thiamine (vitamin B 1 ) deficiency in the Great Lakes has been attributed to elevated levels of thiaminase I enzyme activity in invasive prey species; however, few studies have investigated thiaminase activity in native prey species. Some of the highest levels of thiaminase activity have been measured in invasive dreissenid mussels with little understanding of background levels contributed by native freshwater mussels (Bivalvia: Unionidae). In this study, thiaminase activity was measured in two freshwater mussel species, Elliptio complanata and Strophitus undulatus , from the Delaware and Susquehanna River drainage basins located in north eastern United States. Thiaminase activity was also measured in gravid and non-gravid S. undulatus . Average thiaminase activity differed significantly between species (7.2 and 42.4 μmol/g/min, for E. complanata and S. undulatus respectively) with no differences observed between drainage basins. Gravid S. undulatus had significantly lower thiaminase activity (28.0 μmol/g/min) than non-gravid mussels (42.4 μmol/g/min). Our results suggest that a suite of factors may regulate thiaminase activity in freshwater mussels and that native freshwater mussel thiaminase activity is within the range observed for invasive dreissenids. These results add to our understanding of the complexities in identifying the ecological conditions that set the stage for thiamine deficiency.

Journal of Great Lakes Research↗

USGS2015

Behavioral responses of freshwater mussels to experimental dewatering

Understanding the effects of flow alteration on freshwater ecosystems is critical for predicting species responses and restoring appropriate flow regimes. We experimentally evaluated the effects of 3 dewatering rates on behavior of 6 freshwater mussel species in the context of water-removal rates observed in 21 Atlantic Coast rivers. Horizontal movement differed significantly among species and dewatering rates, but a significant species × dewatering interaction suggested that these factors influence movement in complex ways. Species differences in movement were evident only in controls and under slow dewatering rates, but these differences disappeared at moderate and fast dewatering rates. Burrowing behavior did not differ with respect to species identity or dewatering rate. The proportion of individuals that became stranded did not differ among species, but most individuals became stranded under low and moderate dewatering, and all individuals became stranded under fast dewatering. Mortality after stranding differed strongly among species along a gradient from 25% in Pyganodon cataracta to 92% in Alasmidonta marginata . Together, these results suggest that species behavior may differ under gradual dewatering, but all species in our study are poorly adapted for rapid dewatering. Most of the 21 rivers we assessed experienced dewatering events comparable to our moderate rate, and several experienced events comparable to our fast rate. Dewatering events that exceed the movement or survival capability of most mussel species can be expected to result in assemblage-wide impacts. Consequently, the rate of water level change may be important in refining target flow conditions for restoration.

New Jersey, Pennsylvania↗

USGS2015

An integrated Riverine Environmental Flow Decision Support System (REFDSS) to evaluate the ecological effects of alternative flow scenarios on river ecosystems

In regulated rivers, managers must evaluate competing flow release scenarios that attempt to balance both human and natural needs. Meeting these natural flow needs is complex due to the myriad of interacting physical and hydrological factors that affect ecosystems. Tools that synthesize the voluminous scientific data and models on these factors will facilitate management of these systems. Here, we present the Riverine Environmental Flow Decision Support System (REFDSS), a tool that enables evaluation of competing flow scenarios and other variables on instream habitat. We developed a REFDSS for the Upper Delaware River, USA, a system that is regulated by three headwater reservoirs. This version of the REFDSS has the ability to integrate any set of spatially explicit data and synthesizes modeled discharge for three competing management scenarios, flow-specific 2-D hydrodynamic modeled estimates of local hydrologic conditions (e.g., depth, velocity, shear stress, etc.) at a fine pixel-scale (1 m 2 ), and habitat suitability criteria (HSC) for a variety of taxa. It contains all individual model outputs, computationally integrates these data, and outputs the amount of potentially available habitat for a suite of species of interest under each flow release scenario. Users have the flexibility to change the time period of interest and vary the HSC. The REFDSS was developed to enable side-by-side evaluation of different flow management scenarios and their effects on potential habitat availability, allowing managers to make informed decisions on the best flow scenarios. An exercise comparing two alternative flow scenarios to a baseline scenario for several key species is presented. The Upper Delaware REFDSS was robust to minor changes in HSC (± 10 %). The general REFDSS platform was developed as a user-friendly Windows desktop application that was designed to include other potential parameters of interest (e.g., temperature) and for transferability to other riverine systems.

New Jersey, Pennsylvania↗

USGS2014

Transcriptomic analysis of the mussel Elliptio complanata identifies candidate stress-response genes and an abundance of novel or noncoding transcripts

Mussels are useful indicator species of environmental stress and degradation, and the global decline in freshwater mussel diversity and abundance is of conservation concern. Elliptio complanata is a common freshwater mussel of eastern North America that can serve both as an indicator and as an experimental model for understanding mussel physiology and genetics. To support genetic components of these research goals, we assembled transcriptome contigs from Illumina paired-end reads. Despite efforts to collapse similar contigs, the final assembly was in excess of 136,000 contigs with an N50 of 982 bp. Even so, comparisons to the CEGMA database of conserved eukaryotic genes indicated that ∼20% of genes remain unrepresented. However, numerous candidate stress-response genes were present, and we identified lineage-specific patterns of diversification among molluscs for cytochrome P450 detoxification genes and two saccharide-modifying enzymes: 1,3 beta-galactosyltransferase and fucosyltransferase. Less than a quarter of contigs had protein-level similarity based on modest BLAST and Hmmer3 statistical thresholds. These results add comparative genomic resources for molluscs and suggest a wealth of novel proteins and noncoding transcripts.

PLoS ONE↗

USGS2013

The effects of salinity exposure on multiple life stages of a common freshwater mussel, Elliptio complanata

There is growing concern over the effects of increased salinization on freshwater organisms, which are largely unknown for unionid mussels. Adult and larval Elliptio complanata were exposed to low-level salt concentrations to determine the effects on mussel survival, physiology, and reproduction. Adults were exposed to salt concentrations of 0 parts per thousand (ppt), 2 ppt, 4 ppt, and 6 ppt NaCl and monitored over 7 d for mortality. Treatment groups exposed to 6 ppt and 4 ppt experienced 50% mortality at day 3 and day 4, respectively, with complete mortality by day 7. No mortality was observed in the other treatments. Adults were also exposed to sublethal salinity levels of 1 ppt and 2 ppt NaCl for 4 wk to determine physiological consequences of prolonged salinity exposure. Mussels exposed to 1 ppt and 2 ppt experienced reduced metabolic rates within the first 24 h of exposure that recovered to control levels in the 1-ppt treatment within 7 d. Metabolic recovery did not occur in the 2-ppt treatment by the end of 28 d. Glochidia exposed to 3-ppt NaCl during attachment to their host fish suffered a reduction in attachment success and metamorphosis, resulting in a 10-fold reduction in the number of juveniles produced per host fish. The present study demonstrates that low levels of salt can have a dramatic effect on the reproduction, physiology, and survival of freshwater mussels

Environmental Toxicology and Chemistry↗

USGS2012

Assessment of photographs from wildlife monitoring cameras in Drakes Estero, Point Reyes National Seashore, California

Between 2007 and 2010, National Park Service (NPS) staff at the Point Reyes National Seashore, California, collected over 300,000 photographic images of Drakes Estero from remotely operated wildlife monitoring cameras. The purpose of the systems was to obtain photographic data to help understand possible relationships between anthropogenic activities and Pacific harbor seal ( Phoca vitulina richardsi ) behavior and distribution. The value of the NPS photographs for use in assessing the frequency and impacts of seal disturbance and displacement in Drakes Estero has been debated. In September 2011, the NPS determined that the photographs did not provide meaningful information for development of a Draft Environmental Impact Statement (DEIS) for the Drakes Bay Oyster Company Special Use Permit. Limitations of the photographs included lack of study design, poor photographic quality, inadequate field of view, incomplete estuary coverage, camera obstructions, and weather limitations. The Marine Mammal Commission (MMC) reviewed the scientific data underpinning the Drakes Bay Oyster Company DEIS in November 2011 and recommended further analysis of the NPS photographs for use in characterizing rates and consequences of seal disturbance (Marine Mammal Commission, 2011). In response to that recommendation, the NPS asked the U.S. Geological Survey (USGS) to conduct an independent review of the photographs and render an opinion on the utility of the remote camera data for informing the environmental impact analyses included in the DEIS. In consultation with the NPS, we selected the 2008 photographic dataset for detailed evaluation because it covers a full harbor seal breeding season (March 1 to June 30), provides two fields of view (two cameras were deployed), and represents a time period when cameras were most consistently deployed and maintained. The NPS requested that the photographs be evaluated in absence of other data or information pertaining to seal and human activity in the estuary and that we focus on the extent to which the photographs could be used in understanding the relationship between human activity (including commercial oyster production) and harbor seal disturbance and distribution in the estuary.

California↗