USGS Science⌕ Search

SEARCH · USGS Science

Results for “Restoration Ecology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 721 records · Page 40Linked to original sources

Factors affecting coastal wetland loss and restoration

Opening paragraph: Tidal and nontidal wetlands in the Chesapeake Bay watershed provide vital hydrologic, water-quality, and ecological functions. Situated at the interface of land and water, these valuable habitats are vulnerable to alteration and loss by human activities including direct conversion to non-wetland habitat by dredge-and-fill activities from land development, and to the effects of excessive nutrients, altered hydrology and runoff, contaminants, prescribed fire management, and invasive species. Processes such as sea-level rise and climate change also impact wetlands. Although local, State, and Federal regulations provide for protection of wetland resources, the conversion and loss of wetland habitats continue in the Bay watershed. Given the critical values of wetlands, the Chesapeake 2000 Agreement has a goal to achieve a net gain in wetlands by restoring 25,000 acres of tidal and nontidal wetlands by 2010. The USGS has synthesized findings on three topics: (1) sea-level rise and wetland loss, (2) wetland restoration, and (3) factors affecting wetland diversity.

Book chapter↗

Evaluating drivers of hydrology, water quality, and benthic macroinvertebrates in streams of Fairfax County, Virginia, 2007–18

In 2007, the U.S. Geological Survey partnered with Fairfax County, Virginia, to establish a long-term water-resources monitoring program to evaluate the hydrology, water quality, and ecology of Fairfax County streams and the watershed-scale effects of management practices. Fairfax County uses a variety of management practices, policies, and programs to protect and restore its water resources, but the effects of such strategies are not well understood. This report used streamflow, water-quality, and ecological monitoring data collected from 20 Fairfax County watersheds from 2007 through 2018 to assess the effects of management practices, landscape factors, and climatic conditions on observed nutrient, sediment, salinity, and benthic-macroinvertebrate community responses. Urbanization, climatic variability, and an increase in management practices occurred within Fairfax County during the study period. Impervious cover, housing units, wastewater infrastructure, and (or) stormwater infrastructure increased in most study watersheds. Climatic conditions varied among study years; countywide estimates of average-annual air temperature differed by about 3 degrees Celsius, and total precipitation ranged from about 34 to 63 inches per year. The effects of the management practices, implemented to reduce nitrogen, phosphorus, and (or) sediment loads, are considered in this study. These management practices primarily consist of stormwater retrofits and stream restorations; however, stream restorations account for most of the financial investment and expected load reductions. Management practices were implemented in half of the study watersheds, and most practices were installed and reductions credited late in the study period. Changes in hydrologic response during storm events were evaluated over the study period because many management practices that were implemented were designed to achieve nutrient and sediment reductions by slowing or intercepting runoff. The average number and length of storm events was mostly unchanged throughout the monitoring network. Four watersheds with 10 years of streamflow data showed a mixture of trends in stormflow peak, volume, and rate-of-change. Event-mean nutrient and sediment concentrations from these watersheds were evaluated during storm events and generally showed increases in total phosphorus (TP) and suspended sediment and reductions or no changes in total nitrogen (TN). Landscape inputs of nitrogen and phosphorus and the percentage of inputs delivered to streams were estimated for the study watersheds. Estimated phosphorus from fertilizer and nitrogen from atmospheric deposition represented large nutrient inputs in most watersheds; amounts of other nonpoint sources varied based on land use. Estimated nitrogen inputs declined throughout Fairfax County and in most study watersheds from 2008 through 2018; in comparison, phosphorus input changes were relatively small. Most nonpoint-nutrient inputs were retained on the landscape and did not reach streams, with slightly more nitrogen retention than phosphorus, on average. Retention rates were lower for years with more precipitation and streamflow. After adjusting for streamflow, TN and TP loads were generally higher for years with more nutrient inputs. Calculated as a function of flow-adjusted loads, TP retention declined at most stations from 2009 through 2018, in comparison, TN retention was relatively unchanged. Landscape and climatic conditions affected spatial differences and changes in Fairfax County stream conditions from 2009 through 2018. TN concentrations were higher and increases over time were larger in watersheds with elevated septic-system density. TP concentrations were higher in watersheds with more turfgrass; concentrations were lower, but had larger increases over time, in watersheds with deeper soils. Suspended-sediment concentrations were higher in watersheds with greater stream densities. Specific conductance was higher in watersheds with more developed land use and shallower soils. Benthic-macroinvertebrate index of biotic integrity (IBI) scores were lower in watersheds with high road density and had larger increases over time in bigger, more developed watersheds. Annual variability in TN and TP concentrations and benthic-macroinvertebrate IBI scores was affected by precipitation; annual variability in suspended sediment concentrations and specific conductance was affected by air temperature. After accounting for influences from landscape and climatic conditions, expected management-practice effects were not consistently observed in monitored stream responses. These effects were assessed by comparing expected management-practice load reductions with the timing, direction, and magnitude of changes in storm-event hydrology, nutrient and sediment loads, median-annual water-quality conditions, and benthic-macroinvertebrate IBI scores. An important consideration for future investigations of management-practice effects is how to control for water-quality and ecological variability caused by geologic properties, the urban environment, precipitation, and (or) air temperature. The interpretation of management-practice effects in this report was likely influenced by a combination of factors, including (1) the amount, timing, and location of management-practice implementation; (2) unmeasured landscape and climatic factors; (3) uncertain management-practice expectations; (4) hydrologic variability; and (5) analytical assumptions. Through continued data-collection efforts, particularly after management practices have been completed, many of these factors may become less influential in the future.

Virginia↗

The consequences of landscape change on ecological resources: An assessment of the United States mid-Atlantic region, 1973-1993

Spatially explicit identification of changes in ecological conditions over large areas is key to targeting and prioritizing areas for environmental protection and restoration by managers at watershed, basin, and regional scales. A critical limitation to this point has been the development of methods to conduct such broad-scale assessments. Field-based methods have proven to be too costly and too inconsistent in their application to make estimates of ecological conditions over large areas. New spatial data derived from satellite imagery and other sources, the development of statistical models relating landscape composition and pattern to ecological endpoints, and geographic information systems (GIS) make it possible to evaluate ecological conditions at multiple scales over broad geographic regions. In this study, we demonstrate the application of spatially distributed models for bird habitat quality and nitrogen yield to streams to assess the consequences of landcover change across the mid-Atlantic region between the 1970s and 1990s. Moreover, we present a way to evaluate spatial concordance between models related to different environmental endpoints. Results of this study should help environmental managers in the mid-Atlantic region target those areas in need of conservation and protection.

Ecosystem Health↗

Suturing fragmented landscapes: Mosaic hybrid zones in plants may facilitate ecosystem resiliency

Many widespread plant taxa of western North America have diversified into phenotypically and genetically divergent lineages due to complex biogeographic histories across heterogeneous landscapes. Mosaic hybrid zones can form when geographically co-occurring, yet environmentally distinct, lineages cross-pollinate and form hybrids that occupy unique environmental niches absent of a geographic cline. This expands the total environmental space across which parental and hybrid individuals grow, resulting in larger, less fragmented geographic distributions. Here, we highlight hybridization mosaics across three study systems containing taxa critical to widespread plant communities in western North America: Ericameria nauseosa , Artemisia tridentata , and Sphaeralcea fendleri . The systems contain diverged taxa that co-occur across the landscape and hybridize readily. Hybridization among taxa has facilitated niche expansion into intermediate environments consistent with unique combinations of adaptive genetic variation, creating more continuity within each study system—study systems occupy ~820 to 270,000 km 2 more geographic area by virtue of hybridization. Furthermore, hybrids are predicted to play important roles in future climates, as they may occupy 8 to 475% larger distributions compared to present. Convergent patterns signal mosaic hybridization as an underappreciated mechanism with broad ecological and evolutionary ramifications. Leveraging mosaic hybridization may assist the creation of restoration management plans that aim to mitigate the deleterious effects of habitat fragmentation on ecosystems in the context of climate change.

western United States↗

Rapid colonisation post-displacement contributes to native fish resilience

Native freshwater fish are experiencing global declines. Determining what drives native fish resilience to disturbance is crucial to understanding their persistence in the face of multiple stressors. Fish colonisation ability may be one factor affecting population resilience after disturbance. We conducted displacement experiments in headwater streams in Wyoming, USA, to evaluate mottled sculpin ( Cottus bairdii ) and mountain sucker ( Catostomus platyrhynchus ) colonisation ability. Specifically, we (1) determined whether fish could colonise sites rapidly after displacement, (2) evaluated site-level factors affecting colonisation, and (3) compared species-level differences in movement and colonisation capabilities. Mountain sucker recovered to pre-displacement abundances within 6–11 weeks, but mottled sculpin were still at slightly reduced abundances. For both species, the majority of colonists were unmarked new individuals and size–structure was similar to pre-displacement size–structure. Fish colonisation was best predicted by pre-displacement abundance and an interaction between per cent riparian cover and species identity. The slower colonisation rate of mottled sculpin may relate to movement ability as average daily movement rate and movement extent were significantly greater for mountain sucker. Our results demonstrate that colonisation is one mechanism allowing fish populations to be resilient in the face of disturbance and that species' traits provide insight into fish colonisation capabilities. Experimental approaches provide mechanistic insight into colonisation dynamics, enhancing our understanding of native fish resilience in degraded stream ecosystems and their response to restoration actions.

Wyoming↗

Factors influencing soil invertebrate communities in riparian grasslands of the central platte river floodplain

In the Platte River Valley of central Nebraska, USA, riparian grasslands (also known as wet meadows) have been severely impacted by a reduction in river flows, causing lower ground-water levels and altered seasonal hydroperiods. The potential impacts of these hydrologic changes, as well as the environmental factors that influence wet meadow soil invertebrate communities, are not well understood. An understanding of the ecological processes that influence these invertebrate communities is crucial for maintaining and restoring wet meadows along the Platte River. Our objectives were to describe the soil invertebrate community of wet meadows throughout the growing season and to examine the relative roles of abiotic factors in determining patterns in invertebrate community structure. We conducted the study in 12 wet meadows along the Platte River during 1999 and 2000. We identified 73 invertebrate taxa; 39 were considered soil inhabitants. Total biomass was primarily composed of earthworms, Scarabaeidae, Isopoda, and Elateridae, with earthworms and Scarabaeidae accounting for >82%. Differences in river flow and precipitation patterns influenced some soil invertebrates. Earthworms and Scarabaeidae declined dramatically from 1999 (wet year) to 2000 (dry year). The topographic gradient created by the ridge-swale complex affected several soil invertebrate taxa; Scarabaeidae, Diplopoda, and Lepidoptera biomasses were greatest on drier ridges, while Tipulidae and Isopoda biomasscs were greatest in wetter sloughs. Responses of earthworm taxa to the topographic gradient were variable, but generally, greater biomasses occurred on ridges and mid-elevations. Water-table depth and soil moisture were the most important variables influencing wet meadow soil invertebrates. Because these communities are linked to the hydrologic processes of the Platte River, future alterations of wet meadow hydrology could shift the distribution patterns of many of these invertebrates and possibly eliminate more moisture-tolerant taxa. To maintain wet meadows and their biotic communities, flow management should focus on regaining as much as possible of the former hydrograph through properly timed flows that provide an adequate hydrologic regime for wet meadows. In addition, restoration of wet meadows will depend on restoring the natural topography of wet meadows. ?? 2006, The Society of Wetland Scientists.

Wetlands↗

Planning for population viability on Northern Great Plains national grasslands

Broad-scale information in concert with conservation of individual species must be used to develop conservation priorities and a more integrated ecosystem protection strategy. In 1999 the United States Forest Service initiated an approach for the 1.2× 10 6 ha of national grasslands in the Northern Great Plains to fulfill the requirement to maintain viable populations of all native and desirable introduced vertebrate and plant species. The challenge was threefold: 1) develop basic building blocks in the conservation planning approach, 2) apply the approach to national grasslands, and 3) overcome differences that may exist in agency-specific legal and policy requirements. Key assessment components in the approach included a bioregional assessment, coarse-filter analysis, and fine-filter analysis aimed at species considered at-risk. A science team of agency, conservation organization, and university personnel was established to develop the guidelines and standards and other formal procedures for implementation of conservation strategies. Conservation strategies included coarse-filter recommendations to restore the tallgrass, mixed, and shortgrass prairies to conditions that approximate historical ecological processes and landscape patterns, and fine-filter recommendations to address viability needs of individual and multiple species of native animals and plants. Results include a cost-effective approach to conservation planning and recommendations for addressing population viability and biodiversity concerns on national grasslands in the Northern Great Plains.

Wildlife Society Bulletin↗

Interactions between fire and invasive plants in temperate grasslands of North America

A substantial number of invasive grasses, forbs and woody plants have invaded temperate grasslands in North America. Among the invading species are winter annuals, biennials, cool-season perennials, warm-season perennials, vines, shrubs, and trees. Many of these species have been deliberately introduced and widely planted; some are still used for range improvement, pastures, lawns, and as ornamentals, though many are listed as state or federal noxious weeds. Others have been greatly facilitated by widespread land disturbance. Historically, fire has been a major selective force in the evolution of temperate grasslands. Further, prescribed fire is commonly used as a method of ecological management for native grassland communities as well as in conjunction with restoration efforts. Within this context, it is important to understand how invasive species will interact with natural and prescribed fire regimes. In this paper, we consider what is known about how exotic species that invade temperate grasslands relate to fire. The primary issues addressed for each species are (1) Does fire appear to enhance colonization? (2) To what degree does fire affect the survival of plants? (3) Are plants that are burned able to regrow following fire and, if so, how rapidly can they recover? (4) How important is competition with native species to the response to fire? and (5) What effect does an invasive species have on the characteristics of the fire regime? For many species, results are preliminary, incomplete, or inconsistent among studies. For this reason, many of the conclusions drawn for individual species must be considered preliminary. Based on analyses of individual species, a conceptual framework is presented for considering how invasive plants may interact with fire when they invade an ecosystem. The major categories of influences are the native community, the fire regime, growth conditions for both invasive and native species, and influences that disturbances, human impacts, and landscape characteristics have had in the past and will have in the future. The examples considered in this paper provide support for a few, tentative generalizations. First, among our current worst invaders of temperate grasslands, adaptation to fire is quite variable. Some species are not well adapted to burning and can be easily eliminated; other species are better adapted but can still be eliminated if fire occurs during periods of particular vulnerability and/or at high frequency. There is a set of species that is extremely well adapted to fire and will not be eliminated through burning alone. Second, competitive interactions with native species play a crucial role in the success of nonnative invaders. In cases where differential burn responses between invasive and native species can be exploited, and adequate populations of native dominant species are present, fire can sometimes tip the competitive balance away from invasives. Third, there are a few invasive species that have exceptional attributes and for which there are no easy solutions. The ability of cheatgrass ( Bromus tectorum ) to enhance fire, the ability of Chinese tallow ( Triadica sebifera ) to suppress fire, and the ability of leafy spurge ( Euphorbia esula ) to resprout from repeated injury make these species exceptional threats to native diversity. Finally, the available information for many invasive species is very incomplete, partic- ularly with regard to how fire affects competitive interactions with the native community. There is much more we need to know if we are to consistently predict how invasive species will respond to fire and how burning can best be used to manage for natural diversity.

Conference Paper↗

Restoration of waterbird habitats in Chesapeake Bay: Great expectations or Sisyphus revisited?

In the past half century, many waterbird populations in Chesapeake Bay have declined or shifted ranges, indicating major ecological changes have occurred. While many studies have focused on the problems associated with environmental degradation such as the losses of coastal wetlands and submerged vegetation, a number of restoration efforts have been launched in the past few decades to reverse the "sea of despair." Most pertinent to waterbirds, restoration of submerged aquatic vegetation (SAV) beds, tidal wetland restoration, oyster reef restoration, and island creation/restoration have benefited a number of species. State and federal agencies and non-government agencies have formed partnerships to spawn many projects ranging in size from less than 0.5 ha to ca. 1,000 ha. While most SAV, wetland, and oyster reef projects have struggled to different degrees over the past ten to twenty years with inconsistent methods, irregular monitoring, and unknown reasons for failures, recent improvements in techniques and application of adaptive management have been made. The large dredge-material island projects at Hart-Miller Island near Baltimore, Poplar Island west of Tilghman Island, Maryland, and Craney Island in Portsmouth, Virginia have provided large outdoor "laboratories" for wildlife, fishery, and wetland habitat creation. All three have proven to be important for nesting waterbirds and migrant shorebirds and waterfowl; however nesting populations at all three islands have been compromised to different degrees by predators. Restoration success for waterbirds and other natural resources depends on: (1) establishing realistic, quantifiable objectives and performance criteria, (2) continued monitoring and management (e.g., predator control), (3) targeted research to determine causality, and (4) careful evaluation under an adaptive management regime.

Waterbirds↗

Restoration of waterbird habitats in Chesapeake Bay: Great expectations or Sisyphus revisited?

In the past half century, many waterbird populations in Chesapeake Bay have declined or shifted ranges, indicating major ecological changes have occurred. While many studies have focused on the problems associated with environmental degradation such as the losses of coastal wetlands and submerged vegetation, a number of restoration efforts have been launched in the past few decades to reverse the 'sea of despair.' Most pertinent to waterbirds, restoration of submerged aquatic vegetation (SAV) beds, tidal wetland restoration, oyster reef restoration, and island creation/restoration have benefited a number of species. State and federal agencies and non government agencies have formed partnerships to spawn many projects ranging in size from less than 0.5 ha to ca. 1,000 ha. While most SAV, wetland, and oyster reef projects have struggled to different degrees over the past ten to twenty years with inconsistent methods, irregular monitoring, and unknown reasons for failures, recent improvements in techniques and application of adaptive management have been made. The large dredge-material island at Hart-Miller Island near Baltimore, Poplar Island west of Tilghman Island, Maryland, and Craney Island Portsmouth, Virginia have provided large outdoor 'laboratories' for wildlife, fishery, and wetland habitat creation. All three have proven to be important for nesting waterbirds and migrant shorebirds and waterfowl; however nesting populations at all three islands have been compromised to different degrees by predators. Restoration success for waterbirds and other natural resources depends on: (1) establishing realistic, quantifiable objectives and performance criteria, (2) continued monitoring and management (e.g., predator control), (3) targeted research to determine causality, and (4) careful evaluation under an adaptive management regime.

Book chapter↗

Disruption and restoration of en route habitat, a case study: The Chenier Plain

Cheniers (relict beach ridges) and other habitats adjacent to ecological barriers may be critical linkages in the migratory pathways of long-distance migratory birds. It is important that these wooded habitats provide enough food and cover at the right time to support these birds’ requirements. To date, little attention has been given to the conservation of coastal woodlands, habitats in which en route migrants tend to concentrate in large numbers during migration. Because about one-third of North Americas ’ human population lives within 80 km of the coast, many forest-dwelling landbird migrants now depend on degraded native woodlands and urbanized environments for survival during migration. Restoration or rehabilitation of coastal woodlands, such as the cheniers of southwest Louisiana and southeast Texas, is of particular importance because of historic anthropogenic modifications, their limited geographic extent, and the extraordinary abundance and species richness of migratory birds using them during migration. In this paper, we use the Chenier Plain as a case study to discuss the issue of land use changes and their consequences for maintaining suitable stopover habitat. Results from an ongoing field study in this ecosystem indicate that most forest-dependent migratory birds are tolerant of at least some degradation of chenier forest during migration. However, these results reveal that subtle differences in vegetation composition and structure beneath the canopy of these forests, primarily as a result of livestock grazing and white-tailed deer overbrowsing, can result in differential use by some en route migrants. Species that were most affected by disturbance to the forest understory were early-arriving migrants, dead-leaf foragers, frugivores, and nectarivores. Given that the understory structure and regeneration of chenier forests has been so greatly reduced, and that high densities of nearctic-neotropical migrants tend to concentrate in cheniers during migration, restoration and re-habilitation should be conservation priorities in the Chenier Plain.

Louisiana, Texas↗

Regional estimates of ecological services derived from U.S. Department of Agriculture conservation programs in the Mississippi Alluvial Valley

The Mississippi Alluvial Valley (MAV) is the Nation?s largest floodplain and this once predominantly forested ecosystem provided significant habitat for a diverse flora and fauna, sequestered carbon in trees and soil, and stored floodwater, sediments, and nutrients within the floodplain. This landscape has been substantially altered by the conversion of nearly 75% of the riparian forests, predominantly to agricultural cropland, with significant loss and degradation of important ecosystem services. Large-scale efforts have been employed to restore the forest and wetland resources and the U.S. Department of Agriculture (USDA) Wetlands Reserve Program (WRP) and Conservation Reserve Program (CRP) represent some of the most extensive restoration programs in the MAV. The objective of the WRP is to restore and protect the functions and values of wetlands in agricultural landscapes with an emphasis on habitat for migratory birds and wetland-dependent wildlife, protection and improvement of water quality, flood attenuation, ground water recharge, protection of native flora and fauna, and educational and scientific scholarship. The degree to which these conservation practices can restore ecosystem functions and services is not well known. This project was initiated to quantify existing ecological services derived from USDA conservation practices in the MAV as part of the USDA Conservation Effects Assessment Project, Wetlands Component (CEAP-Wetlands). The U.S. Geological Survey (USGS), in collaboration with the USDA Natural Resources Conservation Service, the USDA Farm Service Agency, the U.S. Fish and Wildlife Service, and Ducks Unlimited, collected data on soils, vegetation, nitrogen cycling, migratory birds, and amphibians from 88 different sites between 2006 and 2008. Results from restored WRP sites were compared to baseline data from active agricultural cropland (AG) to evaluate changes in ecosystem services.

Arkansas, Kentucky, Louisiana, Mississippi, Missou↗

Setting limits: Using air pollution thresholds to protect and restore U.S. ecosystems

More than four decades of research provide unequivocal evidence that sulfur, nitrogen, and mercury pollution have altered, and will continue to alter, our nation's lands and waters. The emission and deposition of air pollutants harm native plants and animals, degrade water quality, affect forest productivity, and are damaging to human health. Many air quality policies limit emissions at the source but these control measures do not always consider ecosystem impacts. Air pollution thresholds at which ecological effects are observed, such as critical loads, are effective tools for assessing the impacts of air pollution on essential ecosystem services and for informing public policy. U.S. ecosystems can be more effectively protected and restored by using a combination of emissions-based approaches and science-based thresholds of ecosystem damage. Based on the results of a comprehensive review of air pollution thresholds, we conclude: ??? Ecosystem services such as air and water purification, decomposition and detoxification of waste materials, climate regulation, regeneration of soil fertility, production and biodiversity maintenance, as well as crop, timber and fish supplies are impacted by deposition of nitrogen, sulfur, mercury and other pollutants. The consequences of these changes may be difficult or impossible to reverse as impacts cascade throughout affected ecosystems. ??? The effects of too much nitrogen are common across the U.S. and include altered plant and lichen communities, enhanced growth of invasive species, eutrophication and acidification of lands and waters, and habitat deterioration for native species, including endangered species. ??? Lake, stream and soil acidification is widespread across the eastern United States. Up to 65% of lakes within sensitive areas receive acid deposition that exceeds critical loads. ??? Mercury contamination adversely affects fish in many inland and coastal waters. Fish consumption advisories for mercury exist in all 50 states and on many tribal lands. High concentrations of mercury in wildlife are also widespread and have multiple adverse effects. ??? Air quality programs, such as those stemming from the 1990 Clean Air Act Amendments, have helped decrease air pollution even as population and energy demand have increased. Yet, they do not adequately protect ecosystems from long-term damage. Moreover they do not address ammonia emissions. ??? A stronger ecosystem basis for air pollutant policies could be established through adoption of science-based thresholds. Existing monitoring programs track vital information needed to measure the response to policies, and could be expanded to include appropriate chemical and biological indicators for terrestrial and aquatic ecosystems and establishment of a national ecosystem monitoring network for mercury. The development and use of air pollution thresholds for ecosystem protection and management is increasing in the United States, yet threshold approaches remain underutilized. Ecological thresholds for air pollution, such as critical loads for nitrogen and sulfur deposition, are not currently included in the formal regulatory process for emissions controls in the United States, although they are now considered in local management decisions by the National Park Service and U.S. Forest Service. Ecological thresholds offer a scientifically sound approach to protecting and restoring U.S. ecosystems and an important tool for natural resource management and policy. ?? The Ecological Society of America.

Issues in Ecology↗

Dam removal: Listening in

Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far, some general conclusions have emerged: (1) physical responses are typically fast, with the rate of sediment erosion largely dependent on sediment characteristics and dam-removal strategy; (2) ecological responses to dam removal differ among the affected upstream, downstream, and reservoir reaches; (3) dam removal tends to quickly reestablish connectivity, restoring the movement of material and organisms between upstream and downstream river reaches; (4) geographic context, river history, and land use significantly influence river restoration trajectories and recovery potential because they control broader physical and ecological processes and conditions; and (5) quantitative modeling capability is improving, particularly for physical and broad-scale ecological effects, and gives managers information needed to understand and predict long-term effects of dam removal on riverine ecosystems. Although these studies collectively enhance our understanding of how riverine ecosystems respond to dam removal, knowledge gaps remain because most studies have been short (< 5 years) and do not adequately represent the diversity of dam types, watershed conditions, and dam-removal methods in the U.S.

Water Resources Research↗

Alligators and crocodiles as indicators for restoration of Everglades ecosystems

Alligators and crocodiles integrate biological impacts of hydrological operations, affecting them at all life stages through three key aspects of Everglades ecology: (1) food webs, (2) diversity and productivity, and (3) freshwater flow. Responses of crocodilians are directly related to suitability of environmental conditions and hydrologic change. Correlations between biological responses and environmental conditions contribute to an understanding of species' status and trends over time. Positive or negative trends of crocodilian populations relative to hydrologic changes permit assessment of positive or negative trends in restoration. The crocodilian indicator uses monitoring parameters (performance measures) that have been shown to be both effective and efficient in tracking trends. The alligator component uses relative density (reported as an encounter rate), body condition, and occupancy rates of alligator holes; the crocodile component uses juvenile growth and hatchling survival. We hypothesize that these parameters are correlated with hydrologic conditions including depth, duration, timing, spatial extent and water quality. Salinity is a critical parameter in estuarine habitats. Assessments of parameters defined for crocodilian performance measures support these hypotheses. Alligators and crocodiles are the charismatic megafauna of the Everglades. They are both keystone and flagship species to which the public can relate. In addition, the parameters used to track trends are easy to understand. They provide answers to the following questions: How has the number of alligators or crocodiles changed? Are the animals fatter or thinner than they should be? Are the animals in the places (in terms of habitat and geography) where they should be? As surely as there is no other Everglades, no other single species defines the Everglades as does the American alligator. The Everglades is the only place in the world where both alligators and crocodiles exist. Crocodilians clearly respond to changes in hydrologic parameters of management interest. These relationships are easy to communicate and mean something to managers, decision makers, and the public. Having crocodilians on the list of system-wide, general indicators provides us with one of the most powerful tools we have to communicate progress of ecosystem restoration in Greater Everglades ecosystems to diverse audiences.

Florida↗

Restoring the Florida Everglades: Insights on integrating sea level rise into decision-support tools

Although coastal ecosystems are impacted by climate change and sea-level rise, many ecological and hydrological models do not yet incorporate sea-level rise projections in their modeling outputs. Therefore, this research examined the various challenges that may prevent sea-level rise from being effectively incorporated in modeling and decision-support tools. We conducted semi-structured interviews with twenty-six professionals involved in Florida’s Everglades restoration. We applied the Diffusions of Innovations Theory to better understand factors that can impact practitioners’ adoption of newly designed decision-support tools that examine sea-level rise in the freshwater Everglades. The Diffusions of Innovations Theory provided insights into practitioners’ perceptions of these tools. We found that these practitioners have a strong interest in using dynamic decision-support tools to plan for sea-level rise impacts on Everglades restoration, particularly when they receive information at appropriate geographic and temporal scales and are given hands-on tools and training. However, challenges that prevent developing these tools include outdated data, limited organizational capacity and funding, limited use of long-term indicators, uncertainty about climate change impacts on local ecosystems, and lack of integration between hydrological and ecological models. Our research also highlights that greater availability of different types of tools can help to meet the needs of the scientific and non-scientific audiences involved in Everglades restoration.

Florida↗

Broad-scale assessments of ecological landscapes: developing methods and applications

The U.S. Department of the Interior (DOI) Bureau of Land Management (BLM) is developing a Landscape Approach for managing multiple uses of public lands by incorporating multiscale information to quantify the effects of natural and human influences on natural resource conditions and trends. A primary goal of the approach is to identify opportunities for resource conservation, restoration, and development. The BLM Landscape Approach is developing assessment methods that promote consistency in management decisions, identify ecological characteristics that promote ecosystem resilience under rapidly changing environmental conditions, and foster collaboration among land management agencies. The BLM Landscape Approach is closely aligned with the DOI&rsquo;s &ldquo;A Strategy for Improving the Mitigation Policies and Practices of The Department of the Interior.&rdquo; A major component of the BLM Landscape Approach is the Rapid Ecoregional Assessment (REA) program. REAs identify important ecosystems and wildlife habitats at broad spatial scales and determine where these resources are at risk from environmental stressors that can affect the integrity of ecological systems. Building on the lessons learned from completed or current REAs, the BLM, in partnership with the U.S. Geological Survey, will perform systematic comparisons of REA methods to identify the most promising suite of landscape-level analysis tools. In addition, the BLM and USGS will develop practical applications that demonstrate how to incorporate assessment information to address existing management issues, such as cumulative effects of proposed management actions. The outcome of these efforts will be a set of comprehensive technical guidance documents for conducting and applying broad-scale assessments.

Fact Sheet↗

Efficacy of plastic mesh tubes in reducing herbivory damage by the invasive nutria ( Myocastor coypus ) in an urban restoration site

The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar&reg; plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar&reg; tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood (Populus balsamifera ssp trichocarpa ) over red osier dogwood ( Cornus sericea) and willow ( Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar&reg; plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes.

Oregon↗