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USGS2016

Misapplied survey data and model uncertainty result in incorrect conclusions about the role of predation on alewife population dynamics in Lake Huron: a comment on He et al. (2015)

Drastic recent and ongoing changes to fish populations and food webs in the Great Lakes have been well-described ( Riley et al. 2008 ; Barbiero et al. 2009 ; Nalepa et al. 2009 ; Fahnenstiel et al. 2010 ; Evans et al. 2011 ; Gobin et al. 2015 ), and uncertainty regarding their potential effects on fisheries has caused concern among scientists and fishery managers (e.g., Dettmers et al. 2012 ). In particular, the relative importance of “bottom-up” (e.g., lower trophic level changes) versus “top-down” (e.g., predation) factors to fish community changes in the Great Lakes have been widely debated (e.g., Barbiero et al. 2011 ; Eshenroder and Lantry 2012 ; Bunnell et al. 2014 ). In Lake Huron, recent ecosystem changes have been particularly profound, and populations of alewife ( Alosa pseudoharengus ), an offshore pelagic prey fish, collapsed in 2003 and have yet to recover ( Riley et al. 2008 , 2014 ). He et al. (2015) recently used a series of linked ecological models to assess the role of predation in the dynamics of the offshore prey fish community in Lake Huron. While we believe that they provide a novel method for combining bioenergetics and stock assessment modeling, we question the validity of their conclusions because of the misapplication of survey data and the lack of critical interpretation of their modeling efforts. Here we describe how He et al. (2015) have misapplied bottom trawl data from Lake Huron, and we provide examples of how this has resulted in erroneous conclusions regarding the importance of predation to the population dynamics and collapse of alewife in Lake Huron.

Canadian Journal of Fisheries and Aquatic Sciences↗

USGS2017

Direct and indirect controls on organic matter decomposition in four coastal wetland communities along a landscape salinity gradient

Coastal wetlands store more carbon than most ecosystems globally. As sea level rises, changes in flooding and salinity will potentially impact ecological functions, such as organic matter decomposition, that influence carbon storage. However, little is known about the mechanisms that control organic matter loss in coastal wetlands at the landscape scale. As sea level rises, how will the shift from fresh to salt-tolerant plant communities impact organic matter decomposition? Do long-term, plant-mediated, effects of sea-level rise differ from direct effects of elevated salinity and flooding? We identified internal and external factors that regulated indirect and direct pathways of sea-level rise impacts, respectively, along a landscape-scale salinity gradient that incorporated changes in wetland type (fresh, oligohaline, mesohaline and polyhaline marshes). We found that indirect and direct impacts of sea-level rise had opposing effects on organic matter decomposition. Salinity had an indirect effect on litter decomposition that was mediated through litter quality. Despite significant variation in environmental conditions along the landscape gradient, the best predictors of above- and below-ground litter decomposition were internal drivers, initial litter nitrogen content and initial litter lignin content respectively. Litter decay constants were greatest in the oligohaline marsh and declined with increasing salinity, and the fraction of litter remaining (asymptote) was greatest in the mesohaline marsh. In contrast, direct effects of salinity and flooding were positive. External drivers, salinity and flooding, stimulated cellulytic activity, which was highest in the polyhaline marsh. Synthesis . Our results indicate that as sea level rises, initial direct effects of salinity will stimulate decay of labile carbon, but over time as plant communities shift from fresh to polyhaline marsh, litter decay will decline, yielding greater potential for long-term carbon storage. These findings highlight the importance of quantifying carbon loss at multiple temporal scales, not only in coastal wetlands but also in other ecosystems where plant-mediated responses to climate change will have significant impacts on carbon cycling.

Journal of Ecology↗

USGS2021

Rigorously valuing the coastal hazard risks reduction provided by potential coral reef restoration in Florida and Puerto Rico

The restoration of coastal habitats, particularly coral reefs, can reduce risks by decreasing the exposure of coastal communities to flooding hazards. In the United States, the protective services provided by coral reefs were recently assessed in social and economic terms, with the annual protection provided by U.S. coral reefs off the coasts of the State of Florida and the Commonwealth of Puerto Rico estimated to be more than 9,800 people and $859 million (2010 U.S. dollars). Hurricanes Irma and Maria in 2017 caused widespread damage to coral reefs in the State of Florida and the Commonwealth of Puerto Rico. Here we combine engineering, ecologic, geospatial, social, and economic data and tools to provide a rigorous valuation of where potential coral reef restoration could decrease the hazard faced by Florida and Puerto Rico’s reef-fronted coastal communities. The three restoration scenarios considered: (1) Ecological restoration, ‘E25’, which assumes planting 0.25-meter (m)-high corals on a (cross-shore) 25-m-wide reef; (2) Structural plus ecological, ‘S25’, which assumes emplacing a 1.00-m high structure with 0.25-m high corals on top on a 25 m wide reef; and (3) structural plus ecological, ‘S05’, which assumes emplacing a 1.00-m high structure with 0.25-m high corals on top on a 5 m wide reef. Planted corals are assumed to increase hydrodynamic roughness, thereby dissipating incident wave energy and decreasing flooding potential. We used a standardized approach to ‘place’ potential restoration projects throughout the whole (linear) extent of reefs bordering Florida and Puerto Rico to identify where coral reef restoration could be useful for meeting flood reduction benefits. We always sited potential restoration projects within the existing distribution of reefs even though many sites were far (kilometers [km]) offshore and some sites were relatively deep (up to 7 m depth). We followed risk-based valuation approaches to map flood zones at 10-square-meter resolution along all 980 km of Florida and Puerto’s Rico reef-lined shorelines for the three potential coral reef restoration scenarios and compare them to the flood zones without coral reef restoration. We quantified the potential coastal flood risk reduction provided by coral reef restoration using the latest information from the U.S. Census Bureau, Federal Emergency Management Agency, and Bureau of Economic Analysis for return-interval storm events. Using the damages associated with each storm probability, we also calculate the change in annual expected damages, a measure of the annual protection gained because of coral reef restoration. We found that the benefits of reef restoration off Florida and Puerto Rico are spatially highly variable. In most areas, we found little or no benefit from reef restoration (for example, restoration sites were far offshore or deep). However, there were a number of key areas where reef restoration could have substantial benefits for flood risk reduction. In particular, we estimated the protection gained by Florida and Puerto Rico’s coral reefs from coral reef restoration to result in: Avoided flooding to more than 5.6 square kilometers (2.16 square miles) of land annually; Avoided flooding affecting more than 3,100 people annually; Avoided direct damages of more than $124.2 million to more than 890 buildings annually; and Avoided indirect damages to more $148.7 million in economic activity owing to housing and business damage annually. Thus, the annual value of flood risk reduction provided by potential coral reef restoration in Florida and Puerto Rico is more than 3,100 people and $272.9 million (2010 U.S. dollars) in economic activity. These data provide stakeholders and decision makers with a spatially explicit, rigorous valuation of how, where, and when potential coral reef restoration in Florida and Puerto Rico can increase critical coastal storm flood reduction benefits. These results help identify areas where reef management, recovery, and restoration could potentially help reduce the risk to, and increase the resiliency of, Florida and Puerto Rico’s coastal communities.

Florida↗

USGS2014

Aquaculture disturbance impacts the diet but not ecological linkages of a ubiquitous predatory fish

Aquaculture operations are a frequent and prominent cause of anthropogenic disturbance to marine and estuarine communities and may alter species composition and abundance. However, little is known about how such disturbances affect trophic linkages or ecosystem functions. In Puget Sound, Washington, aquaculture of the Pacific geoduck clam ( Panopea generosa ) is increasing and involves placing nets and polyvinyl chloride (PVC) tubes in intertidal areas to protect juvenile geoducks from predators. Initial studies of the structured phase of the farming cycle have documented limited impacts on the abundance of some species. To examine the effect of geoduck aquaculture on ecological linkages, the trophic relationships of a local ubiquitous consumer, Pacific staghorn sculpin ( Leptocottus armatus ), to its invertebrate prey were compared between geoduck aquaculture sites and nearby reference areas with no aquaculture. Mark-recapture data indicated that sculpin exhibit local site fidelity to cultured and reference areas. The stomach contents of sculpin and stable isotope signatures of sculpin and their prey were examined to study the trophic ecology of cultured and reference areas. Results showed that the structured phase of geoduck aquaculture initiated some changes to staghorn sculpin ecology, as reflected in sculpin diet through stomach content analysis. However, carbon and nitrogen stable isotopes revealed that the general food web function of sculpin remained unchanged. The source of carbon at the base of the food web and the trophic position of sculpin were not impacted by geoduck aquaculture. The study has important implications for geoduck aquaculture management and will inform regulatory decisions related to shellfish aquaculture policy.

Washington↗

USGS2017

Influence of sediment chemistry and sediment toxicity on macroinvertebrate communities across 99 wadable streams of the Midwestern USA

Simultaneous assessment of sediment chemistry, sediment toxicity, and macroinvertebrate communities can provide multiple lines of evidence when investigating relations between sediment contaminants and ecological degradation. These three measures were evaluated at 99 wadable stream sites across 11 states in the Midwestern United States during the summer of 2013 to assess sediment pollution across a large agricultural landscape. This evaluation considers an extensive suite of sediment chemistry totaling 274 analytes (polycyclic aromatic hydrocarbons, organochlorine compounds, polychlorinated biphenyls, polybrominated diphenyl ethers, trace elements, and current-use pesticides) and a mixture assessment based on the ratios of detected compounds to available effects-based benchmarks. The sediments were tested for toxicity with the amphipod Hyalella azteca (28-d exposure), the midge Chironomus dilutus (10-d), and, at a few sites, with the freshwater mussel Lampsilis siliquoidea (28-d). Sediment concentrations, normalized to organic carbon content, infrequently exceeded benchmarks for aquatic health, which was generally consistent with low rates of observed toxicity. However, the benchmark-based mixture score and the pyrethroid insecticide bifenthrin were significantly related to observed sediment toxicity. The sediment mixture score and bifenthrin were also significant predictors of the upper limits of several univariate measures of the macroinvertebrate community (EPT percent, MMI (Macroinvertebrate Multimetric Index) Score, Ephemeroptera and Trichoptera richness) using quantile regression. Multivariate pattern matching (Mantel-like tests) of macroinvertebrate species per site to identified contaminant metrics and sediment toxicity also indicate that the sediment mixture score and bifenthrin have weak, albeit significant, influence on the observed invertebrate community composition. Together, these three lines of evidence (toxicity tests, univariate metrics, and multivariate community analysis) suggest that elevated contaminant concentrations in sediments, in particular bifenthrin, is limiting macroinvertebrate communities in several of these Midwest streams.

Science of the Total Environment↗

USGS2011

Conservation in the face of climate change: The roles of alternative models, monitoring, and adaptation in confronting and reducing uncertainty

The broad physical and biological principles behind climate change and its potential large scale ecological impacts on biota are fairly well understood, although likely responses of biotic communities at fine spatio-temporal scales are not, limiting the ability of conservation programs to respond effectively to climate change outside the range of human experience. Much of the climate debate has focused on attempts to resolve key uncertainties in a hypothesis-testing framework. However, conservation decisions cannot await resolution of these scientific issues and instead must proceed in the face of uncertainty. We suggest that conservation should precede in an adaptive management framework, in which decisions are guided by predictions under multiple, plausible hypotheses about climate impacts. Under this plan, monitoring is used to evaluate the response of the system to climate drivers, and management actions (perhaps experimental) are used to confront testable predictions with data, in turn providing feedback for future decision making. We illustrate these principles with the problem of mitigating the effects of climate change on terrestrial bird communities in the southern Appalachian Mountains, USA.

Southern Appalachian Mountains↗

USGS2019

Prediction of unprecedented biological shifts in the global ocean

Impermanence is an ecological principle 1 but there are times when changes occur nonlinearly as abrupt community shifts (ACSs) that transform the ecosystem state and the goods and services it provides 2 . Here, we present a model based on niche theory 3 to explain and predict ACSs at the global scale. We test our model using 14 multi-decadal time series of marine metazoans from zooplankton to fish, spanning all latitudes and the shelf to the open ocean. Predicted and observed fluctuations correspond, with both identifying ACSs at the end of the 1980s 4,5,6,7 and 1990s 5,8 . We show that these ACSs coincide with changes in climate that alter local thermal regimes, which in turn interact with the thermal niche of species to trigger long-term and sometimes abrupt shifts at the community level. A large-scale ACS is predicted after 2014—unprecedented in magnitude and extent—coinciding with a strong El Niño event and major shifts in Northern Hemisphere climate. Our results underline the sensitivity of the Arctic Ocean, where unprecedented melting may reorganize biological communities 5,9 , and suggest an increase in the size and consequences of ACS events in a warming world.

Nature Climate Change↗

USGS2021

Heatwave-induced synchrony within forage fish portfolio disrupts energy flow to top pelagic predators

During the Pacific marine heatwave of 2014–2016, abundance and quality of several key forage fish species in the Gulf of Alaska were simultaneously reduced throughout the system. Capelin ( Mallotus catervarius ), sand lance ( Ammodytes personatus ), and herring ( Clupea pallasii ) populations were at historically low levels, and within this community abrupt declines in portfolio effects identify trophic instability at the onset of the heatwave. Although compensatory changes in age‐structure, size, growth or energy content of forage fish were observed to varying degrees among all these forage fish, none were able to fully mitigate adverse impacts of the heatwave, which likely included both top‐down and bottom‐up forcing. Notably, changes to the demographic structure of forage fish suggested size‐selective removals typical of top‐down regulation. At the same time, zooplankton community structure may have driven bottom‐up regulation as copepod community structure shifted towards smaller, warm‐water species, and euphausiid biomass was reduced owing to the loss of cold‐water species. Mediated by these impacts on the forage fish community, an unprecedented disruption of the normal pelagic food web was signaled by higher trophic level disruptions during 2015–2016, when seabirds, marine mammals, and groundfish experienced shifts in distribution, mass mortalities, and reproductive failures. Unlike decadal‐scale variability underlying ecosystem regime shifts, the heatwave appeared to temporarily overwhelm the ability of the forage fish community to buffer against changes imposed by warm water anomalies, thereby eliminating any ecological advantages that may have accrued from having a suite of coexisting forage species with differing life history compensations.

Alaska↗

USGS2004

Biodiversity and ecosystem functioning: Synthesis and perspectives

Does diversity matter in restored communities? This edited book explores the diversity–function debate, which has raged in ecology during the past several decades. The diversity–function question is relevant in restoration, but the question has not yet received a straightforward hearing in the field of restoration science. None of the authors of this book explicitly relate their ideas to restoration, but the book can educate restorationists about the most recent developments in the diversity–function debate. It is also an excellent book for students to learn about the recent developments and historical background of the diversity–function debate and can be used for graduate-level seminars in restoration or plant ecology.

Restoration Ecology↗

USGS2006

Invasion in a diversity hotspot: Exotic cover and native richness in the Californian serpentine flora

Exotic species have been observed to be more prevalent in sites where the richness of native species is highest, possibly reflecting variation among sites in resources, propagule supply, heterogeneity, or disturbance. However, such a pattern leaves unclear whether natives at species-rich sites are subject to especially severe impacts from exotics as a result. We considered this question using path models in which relationships between exotic cover and native richness were evaluated in the presence of correlated environmental factors. At 109 sites on serpentine soils across California, USA, exotic cover was positively correlated with total native herbaceous richness and was negatively correlated with the richness of both serpentine-endemic and rare native herbs. However, in path models that accounted for the influences of soil chemistry, disturbance, overstory cover, and regional rainfall and elevation, we found no indication that exotic cover reduced any component of native herb richness. Rather, our results indicated similarities and differences in the conditions favoring exotic, native, endemic, and rare species. Our results suggest that, in spite of some localized impacts, exotic species are not exerting a detectable overall effect on the community richness of the unique native flora of Californian serpentine. ?? 2006 by the Ecological Society of America.

California↗

USGS2002

Influence of hydrology on life-history parameters of common freshwater fishes from southern Florida

Fishes are essential to the successful functioning of wetland food webs in southern Florida through their roles as prey and predators. Any changes that reduce the population sizes, community composition, or availability of aquatic animals will affect all facets of the ecology of these wetlands. In particular, small and medium-size fishes are important food items for most wading bird species. For this reason, fishes have been recognized by the multi-agency groups responsible for guiding the Everglades restoration process as a key indicator group by which to measure restoration success. Despite the importance of fish for management, gaps in baseline knowledge remain. Basic demographic information, termed life-history parameters, is needed to make predictions about their resilience under alternative management scenarios. These parameters include growth rate, age at maturation, fecundity and life expectancy. However, basic life-history parameters remain to be characterized, even for abundant fish species. Adding to the challenge, life-history characteristics of important Everglades species are known to be plastic in response to environmental conditions and survivorship and recruitment schedules are certain to be influenced by variation in hydroperiod. We intend to study the effect of hydroperiod on recruitment, size/age structure, growth, and fecundity, which, in turn, determine fish population dynamics. At present, data on fish reproduction, age and growth, and other life history characteristics are confined to a few species from a limited area of long-hydroperiod marsh in central Shark River Slough. As we continue the analysis and synthesis of data from the long-term fish collections, life-history information will help explain patterns of fluctuations in the time series. Accurate life-history data are also very important in building credible simulation models like ATLSS. Without empirical life-history data from a range of environments, the model will be simplistic and inadequate.

Florida↗

USGS2023

Sea level rise may pose conservation challenges for the endangered Cape Sable seaside sparrow

Biodiversity conservation under a changing climate is a challenging endeavor. Landscapes are shifting as a result of climate change and sea level rise but plant communities in particular may not keep up with the pace of change. Predictive ecological models can help decision makers understand how species are likely to respond to change and then adjust management actions to align with desired future conditions. Florida’s Everglades is a wetland ecosystem that is host to many species, including a large number of endangered and endemic species. Everglades ecosystem restoration has been ongoing for decades, but consideration of sea level rise impacts in restoration planning is more recent. Incorporating potential impacts from sea level rise into restoration planning should benefit species and their coastal habitats, most notably at the southern Florida peninsula. The endangered Cape Sable seaside sparrow ( Ammospiza maritima mirabilis ) occurs in marl prairie habitat at the southern end of the Everglades. The locations of three of its six subpopulations are proximate to the coast. We used a spatially explicit predictive model, EverSparrow, to estimate probability of sparrow presence considering both hydrologic change from restoration and sea level rise. We found that the probability of sparrow presence decreased with increasing sea level rise. Within approximately 50 years, probability of presence significantly decreased for all three coastal subpopulation areas, with areas above 40% probability increasingly limited. Given the exceptionally low dispersal ability of this species and the geographic restrictions for habitat expansion, our results highlight the importance of freshwater flow into the southern Everglades marl prairie for habitat conservation.

Florida↗

USGS2018

Methods to reduce conflicts between cranes and farmers

Alternative methods to reduce conflicts between cranes and farmers range from relatively simple, inexpensive disturbance methods to changes in land use at a landscape scale. Visual and acoustics disturbance methods can be useful for small fields or gardens but require frequent changes to prevent habituation by the cranes. Changes in farming practices can be implemented by individual farmers and matched to the local situation. By altering timing of seeding and harvest, harvest methods, and other management practices, farmers can minimize the vulnerability of the crop or its attractiveness to cranes. Crop damage can be reduced by strategically locating high-risk crops away from crane roosts or high-use areas. Diversionary fields, where cranes can forage on nutritious, preferred foods near their roost without disturbance, are one of the more effective methods to reduce crop damage. Artificial feeding may be appropriate as a temporary measure but its long-term use should only be a last option where no alternative wintering areas or food resources are available or restorable. Chemical treatment of seeds can deter cranes from taking newly sown seeds and seedlings. Conflicts with farmers can be mitigated by financial or other compensation, or through conservation approaches. Financial mechanisms should be used cautiously as they can dilute or corrupt local traditions of tolerance. An integrated approach, using several methods, is more likely to be effective in the long term. Farmers and communities are more likely to embrace alternative measures if they understand basic crane ecology and if the measures are clearly beneficial to the farmers. Developing a broader range of tools to better understand the conflict, to understand farmer perceptions of cranes, and to help implement strategies to improve positivist attitudes is necessary. Multi-disciplinary approaches that incorporate social, economic as well as ecological aspects of the issue are very rare, and much needed to develop workable solutions.

Book chapter↗

USGS2010

Water quality and ecological condition of urban streams in Independence, Missouri, June 2005 through December 2008

To identify the sources of selected constituents in urban streams and better understand processes affecting water quality and their effects on the ecological condition of urban streams and the Little Blue River in Independence, Missouri the U.S. Geological Survey in cooperation with the City of Independence Water Pollution Control Department initiated a study in June 2005 to characterize water quality and evaluate the ecological condition of streams within Independence. Base-flow and stormflow samples collected from five sites within Independence, from June 2005 to December 2008, were used to characterize the physical, chemical, and biologic effects of storm runoff on the water quality in Independence streams and the Little Blue River. The streams draining Independence-Rock Creek, Sugar Creek, Mill Creek, Fire Prairie Creek, and the Little Blue River-drain to the north and the Missouri River. Two small predominantly urban streams, Crackerneck Creek [12.9-square kilometer (km2) basin] and Spring Branch Creek (25.4-km2 basin), were monitored that enter into the Little Blue River between upstream and downstream monitoring sites. The Little Blue River above the upstream site is regulated by several reservoirs, but streamflow is largely uncontrolled. The Little Blue River Basin encompasses 585 km2 with about 168 km2 or 29 percent of the basin lying within the city limits of Independence. Water-quality samples also were collected for Rock Creek (24.1-km2 basin) that drains the western part of Independence. Data collection included streamflow, physical properties, dissolved oxygen, chloride, metals, nutrients, common organic micro-constituents, and fecal indicator bacteria. Benthic macroinvertebrate community surveys and habitat assessments were conducted to establish a baseline for evaluating the ecological condition and health of streams within Independence. Additional dry-weather screenings during base flow of all streams draining Independence were conducted to identify point-source discharges and other sources of potential contamination. Regression models were used to estimate continuous and annual flow-weighted concentrations, loadings, and yields for chloride, total nitrogen, total phosphorus, suspended sediment, and Escherichia coli bacteria densities. Base-flow and stormflow water-quality samples were collected at five sites within Independence. Base-flow samples for Rock Creek and two tributary streams to the Little Blue River exceeded recommended U.S. Environmental Protection Agency standards for the protection of aquatic life for total nitrogen and total phosphorus in about 90 percent of samples, whereas samples collected at two Little Blue River sites exceeded both the total nitrogen and total phosphorus standards less often, about 30 percent of the time. Dry-weather screening identified a relatively small number (14.0 percent of all analyses) of potential point-source discharges for total chlorine, phenols, and anionic surfactants. Stormflow had larger median measured concentrations of total common organic micro-constituents than base flow. The four categories of common organic micro-constituents with the most total detections in stormflow were pesticides (100 percent), polyaromatic hydrocarbons and combustion by-products (99 percent), plastics (93 percent), and stimulants (91 percent). Most detections of common organic micro-constituents were less than 2 micrograms per liter. Median instantaneous Escherichia coli densities for stormflow samples showed a 21 percent increase measured at the downstream site on the Little Blue River from the sampled upstream site. Using microbial source-tracking methods, less than 30 percent of Escherichia coli bacteria in samples were identified as having human sources. Base-flow and stormflow data were used to develop regression equations with streamflow and continuous water-quality data to estimate daily concentrations, loads, and yields of various water-quality contaminants.

Scientific Investigations Report↗

USGS2020

Ambrosia beetle (Coleoptera: Curculionidae) communities and frass production in ʻŌhiʻa (Myrtales: Myrtaceae) infected with Ceratocystis (Microascales: Ceratocystidaceae) fungi responsible for Rapid ʻŌhiʻa Death

Rapid ʻŌhiʻa Death (ROD) is a deadly disease that is threatening the native Hawaiian keystone tree species, ʻōhiʻa lehua ( Metrosideros polymorpha Gaudich). Ambrosia beetles (Curculionidae: Scolytinae) and their frass are hypothesized to play a major role in the spread of ROD, although their ecological niches and frass production within trees and across the landscape are not well understood. We characterized the beetle communities and associated frass production from bolts (tree stem sections) representative of entire individual ʻōhiʻa trees from multiple locations across Hawaiʻi Island by rearing beetles and testing their frass for viable ROD-causing fungi. Additionally, we estimated frass production for three beetle species by weighing their frass over time. We found that Xyleborinus saxesenii (Ratzburg), Xyleborus affinis Eichhoff, Xyleborus ferrugineus (Fabricius), Xyleborus perforans (Wollaston), and Xyleborus simillimus Perkins were commonly found on ROD-infected ʻōhiʻa and each produced frass containing viable Ceratocystis propagules. The Hawaiʻi Island endemic beetle and the only native ambrosia beetle associated with ʻōhiʻa, X. simillimus , was limited to high elevations and appeared to utilize similar tree heights or niche dimensions as the invasive X. ferrugineus . Viable Ceratocystis propagules expelled in frass were found throughout entire tree bole sections as high as 13 m. Additionally, we found that X. ferrugineus produced over 4× more frass than X. simillimus . Our results indicate the ambrosia beetle community and their frass play an important role in the ROD pathosystem. This information may help with the development and implementation of management strategies to control the spread of the disease.

Hawaii↗

USGS2021

Transient disease dynamics across ecological scales

Analyses of transient dynamics are critical to understanding infectious disease transmission and persistence. Identifying and predicting transients across scales, from within-host to community-level patterns, plays an important role in combating ongoing epidemics and mitigating the risk of future outbreaks. Moreover, greater emphases on non-asymptotic processes will enable timely evaluations of wildlife and human diseases and lead to improved surveillance efforts, preventive responses, and intervention strategies. Here, we explore the contributions of transient analyses in recent models spanning the fields of epidemiology, movement ecology, and parasitology. In addition to their roles in predicting epidemic patterns and endemic outbreaks, we explore transients in the contexts of pathogen transmission, resistance, and avoidance at various scales of the ecological hierarchy. Examples illustrate how (i) transient movement dynamics at the individual host level can modify opportunities for transmission events over time; (ii) within-host energetic processes often lead to transient dynamics in immunity, pathogen load, and transmission potential; (iii) transient connectivity between discrete populations in response to environmental factors and outbreak dynamics can affect disease spread across spatial networks; and (iv) increasing species richness in a community can provide transient protection to individuals against infection. Ultimately, we suggest that transient analyses offer deeper insights and raise new, interdisciplinary questions for disease research, consequently broadening the applications of dynamical models for outbreak preparedness and management.

Theoretical Ecology↗

USGS2015

Metagenomic analysis of planktonic microbial consortia from a non-tidal urban-impacted segment of James River

Knowledge of the diversity and ecological function of the microbial consortia of James River in Virginia, USA, is essential to developing a more complete understanding of the ecology of this model river system. Metagenomic analysis of James River's planktonic microbial community was performed for the first time using an unamplified genomic library and a 16S rDNA amplicon library prepared and sequenced by Ion PGM and MiSeq, respectively. From the 0.46-Gb WGS library (GenBank:SRR1146621; MG-RAST:4532156.3), 4 × 10 6 reads revealed >3 × 10 6 genes, 240 families of prokaryotes, and 155 families of eukaryotes. From the 0.68-Gb 16S library (GenBank:SRR2124995; MG-RAST:4631271.3; EMB:2184), 4 × 10 6 reads revealed 259 families of eubacteria. Results of the WGS and 16S analyses were highly consistent and indicated that more than half of the bacterial sequences were Proteobacteria , predominantly Comamonadaceae . The most numerous genera in this group were Acidovorax (including iron oxidizers, nitrotolulene degraders, and plant pathogens), which accounted for 10 % of assigned bacterial reads. Polaromonas were another 6 % of all bacterial reads, with many assignments to groups capable of degrading polycyclic aromatic hydrocarbons. Albidiferax (iron reducers) and Variovorax (biodegraders of a variety of natural biogenic compounds as well as anthropogenic contaminants such as polycyclic aromatic hydrocarbons and endocrine disruptors) each accounted for an additional 3 % of bacterial reads. Comparison of these data to other publically-available aquatic metagenomes revealed that this stretch of James River is highly similar to the upper Mississippi River, and that these river systems are more similar to aquaculture and sludge ecosystems than they are to lakes or to a pristine section of the upper Amazon River. Taken together, these analyses exposed previously unknown aspects of microbial biodiversity, documented the ecological responses of microbes to urban effects, and revealed the noteworthy presence of 22 human-pathogenic bacterial genera (e.g., Enterobacteriaceae , pathogenic Pseudomonadaceae , and ‘ Vibrionales' ) and 6 pathogenic eukaryotic genera (e.g., Trypanosomatidae and Vahlkampfiidae). This information about pathogen diversity may be used to promote human epidemiological studies, enhance existing water quality monitoring efforts, and increase awareness of the possible health risks associated with recreational use of James River.

Virginia↗

USGS2002

Rocky Mountain futures: An ecological perspective

The Rocky Mountain West is largely arid and steep, with ecological scars from past human use visible for hundreds of years. Just how damaging were the past 150 years of activity? How do current rates of disturbance compare with past mining, grazing, and water diversion activities? In the face of constant change, what constitutes a "natural" ecosystem? And can a high quality of life be achieved for both human and natural communities in this region. Rocky Mountain Futures presents a comprehensive and wide-ranging examination of the ecological consequences of past, current, and future human activities in the Rocky Mountain region of the United States and Canada. The book brings together 32 leading ecologists, geographers, and other scientists and researchers to present an objective assessment of the cumulative effects of human activity on the region's ecological health and to consider changes wrought by past human use. This combined view of past and present reveals where Rocky Mountain ecosystems are heading, and the authors project what the future holds based upon current economic and social trends and the patterns that emerge from them. The book: examines the biogeographic and paleoenvironmental setting and historical climate that have shaped Rocky Mountain ecosystems traces the direct human influences on landscapes and ecosystems over the past 150 years explores the cumulative effects of past, present, and projected future human activities on tundra, subalpine and montane forests, valleys, grasslands, and waters offers case studies that illustrate specific examples of human influence and current efforts to restore the environment Case studies focus on northern New Mexico; Summit County, Colorado; Flathead Valley, Montana; and Alberta, Canada. Among the contributors are Craig D. Allen, N. Thompson Hobbs, Linda L. Joyce, Robert E. Keane, David Schindler, Timothy R. Seastedt, David Theobald, Diana Tomback, William Travis, Cathy Whitlock, and Jack Stanford. The United Nations has proclaimed 2002 as the International Year of Mountains to increase international awareness of the global importance of mountain ecosystems. The case-based multidisciplinary approach of this book constitutes an important new model for understanding the implications of land-use practices and economic activity on mountains, and will serve a vital role in improving decisionmaking both in the Rocky Mountains and in other parts of the world that face similar challenges.

Book↗