Marshallia pulchra is a globally rare forb endemic to riverscour ecosystems within high-gradient rivers in the Appalachian Plateau of eastern North America. Given the high conservation priority and limited ecological understanding of M. pulchra, we sought to establish knowledge pertaining to the hydrologic conditions of sites supporting this species. We assessed flow records for 10 rivers to determine if climate change is modifying flood frequency, magnitude, or duration of M. pulchra-supporting rivers. Records in the Youghiogheny River were also linked to cameras trained on individual plants to quantify the flood frequency and duration sustained annually. Finally, we used a century of M. pulchra presence/absence data from the Youghiogheny River to assess long-term persistence. Discharge records indicate that floods in smaller, free-flowing rivers are becoming more frequent at a rate of up to one flood per year. However, we detected no trends suggesting that floods are becoming more intense. M. pulchra individuals in the Youghiogheny are inundated a median of 17 times annually, mostly during winter and spring, and usually for periods less than 2 d. Results suggest that the long-term viability of M. pulchra in the Youghiogheny may be diminishing, as individuals were absent in nearly 40% of previously occupied sites during the most recent surveys. Given the signs of population decline in the Youghiogheny, additional investigations exploring the hydroecology of M. pulchra are urgently needed, especially those that consider the role of invasive species in changes to riverscour ecosystem dynamics.

Riverscour is an eclectic assemblage of highly biodiverse riparian natural communities that share characteristics with grasslands, savannas, glades, wetlands, and floodplains. We define "riverscour" as "open riparian habitats of rocky, stable-substrate (bedrock, boulder, cobble) zones, often along high-gradient streams, where periodic high-energy flows (water, ice, debris) and edaphic factors inhibit woody vegetation and promote persistent grassland-shrubland-open woodland-outcrop communities rich in conservative heliophytes." A key factor distinguishing riverscour from gravel and sand bars and other floodplain habitats is that these areas are underlain by more stable substrates, which resist structural reworking by floodwaters. Within Eastern Unglaciated North America, we mapped 1322 stream reaches totaling 2385.8 km containing riverscour. Given their small size, these communities support a disproportionately large number of rare, endemic, and undescribed species. For example, within a five-county area in Tennessee, riverscour makes up significantly less than 1% of the area but contributes at least 37 (25%) of the region's 150 state- and federally-listed vascular plant species. There are numerous threats to riverscour, the greatest being inundation caused by impoundment of rivers and associated downstream hydrologic alterations. Interruption of scouring processes associated with flooding and/or ice promotes succession toward larger woody species and away from open herbaceous/shrub-dominated vegetation. Other threats include invasive species, recreation pressure, and climate change. These threats, coupled with high biodiversity and historical losses, make protection and proper management of riverscour ecosystems especially important in conserving the native biodiversity of eastern North America.

Continental- and regional-scale assessments of gaps in protected area networks typically use relatively coarse range maps for well documented species groups, creating uncertainty about the fate of unexamined biodiversity and providing insufficient guidance for land managers. By building habitat suitability models for a taxonomically diverse group of 2216 imperiled plants and animals, we revealed comprehensive and detailed protection opportunities in the conterminous United States. Summing protection-weighted range-size rarity (PWRSR, the product of the percent of modeled habitat outside of protected areas and the inverse of modeled habitat extent) uncovered novel patterns of biodiversity importance. Concentrations of unprotected imperiled species in places such as the northern Sierra Nevada, central and northern Arizona, the Rocky Mountains of Utah and Colorado, southeastern Texas, southwestern Arkansas, and Florida's Lake Wales Ridge have rarely if ever been featured in continental- and regional-scale analyses. Inclusion of diverse taxa (vertebrates, freshwater mussels, crayfishes, bumble bees, butterflies, skippers, and vascular plants) partially drove these new patterns. When analyses were restricted to groups typically included in previous studies (birds, mammals, and amphibians), up to 53% of imperiled species in other groups were left out. The finer resolution of modeled inputs (990 m) also resulted in a more geographically dispersed pattern. For example, 90% of the human population of the conterminous United States lives within 50 km of modeled habitat for one or more species with high PWRSR scores. Over one-half of the habitat for 818 species occurs within federally lands managed for biodiversity protection; an additional 360 species have over one-half of their modeled habitat on federal multiple use land. Freshwater animals occur in places with poorer landscape condition but with less exposure to climate change than other groups, suggesting that habitat restoration is an important conservation strategy for these species. The results provide fine-scale, taxonomically diverse inputs for local and regional priority-setting and show that although protection efforts are still widely needed on private lands, notable gains can be achieved by increasing protection status on selected federal lands.

Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement : Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats.

First posted May 20, 2021 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey640 Grassmere Park Drive Nashville, TN 37211 The unglaciated southeastern United States is a biodiversity hotspot, with a disproportionate amount of this biodiversity concentrated in grasslands. Like most hotspots, the Southeast is also threatened by human activities, with the total reduction of southeastern grasslands estimated as 90 percent (upwards to 100 percent for some types) and with many threats escalating today. This report summarizes the results of a multistakeholder workshop organized by the Southeastern Grasslands Initiative and the U.S. Geological Survey, held in January 2020 to provide a scientific needs assessment to help inform the Species Status Assessment (SSA) process under the U.S. Endangered Species Act, with a focus on grassland species and communities of conservation concern in the southeastern United States. This report reviews the ecology of southeastern grasslands, including influences on their origin, maintenance, and high species richness and endemism; presents findings from the workshop; and discusses science questions, hypotheses, and possibilities for future research projects to help fill key knowledge gaps.Participants in the January 2020 workshop, representing diverse expertise in various topics in southeastern grassland ecology, were tasked with identifying major threats to grassland species in the Southeast as well as potential ways to make the SSA process more efficient and effective. An underlying assumption and starting place for workshop discussion was that an ecosystem-based approach to the SSA process is more cost-efficient than a species-by-species approach, in large part because many species with similar biological requirements can be addressed by the same actions. Nevertheless, one partner in this effort, the U.S. Fish and Wildlife Service, does require specific attention be given to taxa that have been petitioned for Federal listing, though as often as possible these taxa are considered alongside a larger group of priority taxa with an ecosystem approach.For group discussions, workshop participants followed a modified “World Café” method, a structured conversational approach for knowledge sharing. Group discussions focused on five categories of threats to grassland communities and species: (1) habitat loss, fragmentation, and disruption of functional population connectivity; (2) climate change, especially changes in temperature and precipitation, including intensity and seasonality, and impacts on soil moisture, groundwater levels, and other ecosystem parameters; (3) changes to disturbance regimes, as influenced by climate and land-use change, extinctions, and human attitudes and behaviors; (4) invasive species (not limited to nonnative species); and (5) localized or subregional impacts such as sea-level rise. In addition to group discussions, workshop participants—as well as other grassland experts who were unable to attend the workshop—completed a preworkshop survey concerning challenges and opportunities for grassland conservation. Findings reported here under each of these topics represent ideas, problems, hypotheses, and questions identified by a diverse community of grassland managers and researchers which may be addressed by future research and monitoring in southeastern grassland ecosystems to help guide science-based conservation of grassland-dependent species.

One hundred ninety-nine species of bryophytes are documented for Erie County, Pennsylvania, representing 34% of the Pennsylvania bryophyte flora. This work is the result of scattered surveys over multiple years and the 2012 Crum Workshop. Aneura maxima, Calypogeia integristipula, C. sphagnicola, Fuscocephaloziopsis loitlesbergeri, F. macrostachya, F. pleniceps, Cephaloziella hyalina, and Campylium protensum are reported new to the state, and an 83 species are reported new for the county. Nearly 40% of the species on this list are considered “rare” and tracked as critically imperiled (S1), imperiled (S2), or vulnerable (S3) by Pennsylvania Natural Heritage Program, highlighting the critical role of intensive surveys for bryophyte conservation.

Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long-term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi-million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post-project assessment should include examination of a wider range of indicators.

Sea Level and Climate 4. Oceanography Richard Z. Poore, Richard Z. Poore U.S. Geological Survey, Reston, VirginiaSearch for more papers by this authorChristopher Tracey, Christopher Tracey U.S. Geological Survey, Reston, VirginiaSearch for more papers by this authorRichard S. Williams Jr., Richard S. Williams Jr. U.S. Geological Survey, Woods Hole, MassachusettsSearch for more papers by this author Richard Z. Poore, Richard Z. Poore U.S. Geological Survey, Reston, VirginiaSearch for more papers by this authorChristopher Tracey, Christopher Tracey U.S. Geological Survey, Reston, VirginiaSearch for more papers by this authorRichard S. Williams Jr., Richard S. Williams Jr. U.S. Geological Survey, Woods Hole, MassachusettsSearch for more papers by this author First published: 15 July 2005 https://doi.org/10.1002/047147844X.oc2148 This article is a US Government work and, as such, is in the public domain in the United States of America. Read the full textAbout ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Reading List Fairbanks, R.G. (1989). A 17,000-year glacio-eustatic sea level record; influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation. Nature 342(6250): 637–642. 10.1038/342637a0 Web of Science®Google Scholar Williams, R.S., and Hall, D.K. (1993). Glaciers, in Chapter on the cryo-sphere, in R.J. Gurney, J.L. Foster, and C.L. Parkinson, eds., Atlas of Earth Observations Related to Global Change. Cambridge University Press, Cambridge, UK, pp. 401–422. Google Scholar Water EncyclopediaBrowse other articles of this reference work:BROWSE BY TOPICBROWSE A-Z ReferencesRelatedInformation