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At least 19 recordsLinked to original sources

Historical wetlands in Oregon's Willamette Valley: Implications for restoration of winter waterbird habitat

Before agricultural expansion in the 19th century, river valleys of North America supported expanses of wetland habitat. In restoring these landscapes, it is important to understand their historical condition and biological function. Synthesizing historical primary accounts (from explorers, travelers, settlers, and farmers) with contemporary knowledge of these wetland systems, we developed a profile of the wetlands and their use by nonbreeding waterbirds (e.g., waterfowl, wading birds, and shorebirds) within the Willamette Valley, Oregon, ca. 1840. We found evidence for three types of wetlands used by non-breeding waterbirds in fall, winter, and spring: emergent wetlands, riverine wetlands, and wetland prairie. The most extensive wetland type was wetland prairie, which functioned as fall/winter habitat for waterbirds, but only while native Kalapuyans managed the region with fire. Since the mid-1800s, four species, in particular, have decreased their use of the Willamette Valley: trumpeter swan (Cygnus buccinator), snow goose (Chen caerulescens), sandhill crane (Grus canadensis), and long-billed curlew (Numenius americanus). Information suggests that ca. 1840, waterbirds and their habitats were more abundant in the Willamette Valley than today. Restoration of the Willamette Valley landscape is warranted, and today's agricultural wetlandsa??former wetland prairiea??hold highest restoration potential.

Wetlands↗

Potential toxicity of complex mixtures in surface waters from a nationwide survey of United States streams: Identifying in vitro bioactivities and causative chemicals

While chemical analysis of contaminant mixtures remains an essential component of environmental monitoring, bioactivity-based assessments using in vitro systems increasingly play a role in the detection of biological effects. Historically, in vitro assessments focused on a few biological pathways, e.g., aryl hydrocarbon receptor (AhR) or estrogen receptor (ER) activities. High-throughput screening (HTS) technologies have greatly increased the number of biological targets and processes that can be rapidly assessed. Here we screened extracts of surface waters from nationwide survey of United States (US) streams for bioactivities associated with 69 different endpoints using two multiplexed HTS assays. Bioactivity of extracts from 38streams was evaluated and compared with concentrations of over 700 analytes to identify chemicals contributing to observed effects. Eleven primary biological endpoints were detected. Pregnane X receptor and AhR-mediated activities were the most commonly detected. Measured chemicals did not completely account for AhR and PXR responses. Surface waters with AhR and PXR effects were associated with low intensity, developed land-cover. Likewise, elevated bioactivities frequently associated with wastewater discharges included endocrine related endpoints— ER and glucocorticoid receptor (GR). These results underscore the value of bioassay-based monitoring of environmental mixtures for detecting biological effects that could not be ascertained solely through chemical analyses.

Environmental Science & Technology↗

Water-resources-related information for the Oneida Reservation and vicinity, Wisconsin

Water-resources information has been compiled from 82 studies in which data were collected from the Oneida Reservation and vicinity. Forty-seven studies addressed surface-water issues, 33 studies addressed ground-water issues, and 23 studies addressed aquatic-biology issues. Some multidisciplinary studies are included in more than one category. Most of the surface-water studies summarized in this report included both water-quality and flow information. Several surface-water studies provided detailed short-term descriptions of surface- water quality and flow for parts of the Reservation and vicinity. Surface-water and stream-sediment quality data from several data bases have been compiled for this report. Most of the compiled data come from two sites on Duck Creek. Data from Duck Creek were analyzed for trends in concentrations of suspended sediment, dissolved nitrite plus nitrate, and dissolved atrazine. No trends were detected for any of these constituents. Trends in concentration of most constituents in surface-water samples were not calculated because of the short period of data collection at nearly all of the sites. Most of the ground-water reports that were identified included both quality and quantity and flow information. None of the ground-water studies provided a detailed description of ground-water quality for the Reservation as a whole. Several reports provide varied and detailed information for ground-water models that are useful for understanding hydrogeology and ground-water flow for the Reservation and vicinity. Ground-water quality data from 180 wells, compiled from several data bases, provided an incomplete summary of the condition of the drinking- water resources of the Reservation. Only 12 constituents, from a small number of wells, exceeded a USEPA drinking-water limit. Most of the exceedences were for trace metals and organics. No exceedences for pesticides or nitrate were reported; however, pesticide data were collected from only a small number of wells. Most of the aquatic biology studies described in this report include fish data, habitat data, or calculations of biotic index values, most of which comes from Duck Creek. Historical aquatic biology data for the Reservation and vicinity are limited. Most of the 23 studies described here were done since 1992. Most of the biota-quality data compiled for this report come from several sites on Duck Creek and represent a small number of samples. Results of the community survey regarding the water resources of the Oneida Reservation indicate that water usage by Tribal members today has declined when compared to the past. The most common reason given for the decline in usage was pollution. Most of those surveyed perceived Duck Creek as being "polluted," but about 50 percent thought that water quality in the Reservation was improving.

Wisconsin↗

Water-quality assessment of the upper Snake River Basin, Idaho and western Wyoming — Summary of aquatic biological data for surface water through 1992

The 35,800-square-mile upper Snake River Basin in eastern Idaho and western Wyoming was one of 20 areas selected for water-quality study under the National Water-Quality Assessment Program. As part of the initial phase of the study, data were compiled to describe the current (1992) and historical aquatic biological conditions of surface water in the basin. This description of natural and human environmental factors that affect aquatic life provides the framework for evaluating the status and trends of aquatic biological conditions in streams of the basins. Water resource development and stream alterations, irrigated agriculture, grazing, aquaculture, and species introductions have affected stream biota in the upper Snake River Basin. Cumulative effects of these activities have greatly altered cold-water habitat and aquatic life in the middle Snake River reach (Milner Dam to King Hill). Most of the aquatic Species of Special Concern in the basin , consisting of eight native mollusks and three native fish species, are in this reach of the Snake River. Selected long-term studies, including comprehensive monitoring on Rock Creek, have shown reduced pollutant loadings as a result of implementing practice on cropland; however, aquatic life remains affected by agricultural land use. Community level biological data are lacking for most of the streams in the basin, especially for large river. Aquatic life used to assess water quality of the basin includes primarily macroinvertebrate and fish communities. At least 26 different macroinvertebrate and fish community metrics have been utilized to assess water quality of the basin. Eight species of macroinvertebrates and fish are recognized as Species of Special Concern. The native fish faunas of the basin are composed primarily of cold-water species representing 5 families and 26 species. An additional 13 fish species have been introduced to the basin. Concentrations of synthetic organic compounds and trace-element contaminants in whole fish collected in the basin during 1970-90 generally did not exceed National Academy of Sciences and National Academy of Engineering concentration guidelines or the 1980-81 geometric mean concentrations from samples collected as part of the U.S. Fish and Wildlife Service National Contaminant Biomonitoring Program. Currently, there are no State fish consumption advisories on any streams in the basin, The organochlorine compounds DDT and PCB's were the most frequently detected fish tissue contaminant. Selected long-term data on DDT, its metabolites, and PCB's indicate decreasing concentrations of these compounds. Arsenic, mercury, and selenium were slightly elevated compared with nationwide baseline concentrations and may indicate bioaccumularion in the food chain. Concentrations of most other trace elements in fish tissue were below levels of concerns for the protection of humans and wildlife.

Idaho, Wyoming↗

A census of marine life: Unknowable or just unknown?

As an introduction to the entire volume, this article outlines the relationships among the five elements of the Census of Marine Life (CoML) that create new knowledge: (1) The Ocean Biogeographic Information System (OBIS), a marine component of the Global Biodiversity Information Facility, links marine databases around the world to provide an Internet accessible, dynamic interface for comparing species-level, geo-referenced biodiversity data in relation to ocean habitats. The entire CoML field project data will be managed in and accessible through OBIS. (2) The History of Marine Animal Populations (HMAP) is a unique new synthesis of historical and biological research that will document marine biodiversity, globally, up to 500 years ago, before significant human impact, and store it in formats compatible with modern data in OBIS. (3) The Scientific Committee on Oceanic Research Working Group 118 monitors and recommends advanced marine technologies, ready to be routinely used in CoML field projects. (4) CoML Initial Field Projects develop and calibrate these technologies in selected regions to facilitate and accelerate global biodiversity research. As calibrated technologies and protocols are adopted in many regions, qualitative and quantitative biodiversity discoveries accumulate. (5) The Future of Marine Animal Populations (FMAP) program will insure that the data in OBIS are suitable for modeling and predicting changes in global biodiversity in response to fishing, pollution, and climate change challenges. It will make datasets available for hindcasting and forecasting analyses linked to physical ocean observations and assist in documenting the impacts of conservation efforts on sustainability.

Oceanologica Acta↗

Differing Eocene floral histories in southeastern North America and Western Europe: Influence of paleogeography

Pollen data show that in southeastern North America, the Eocene angiosperm flora attained its maximum relative diversity some 8 m.y. after the late early Eocene to earliest middle Eocene climatic maximum. Increasing diversity resulted in part from the flora's position on a large continent which allowed easy migration. In western Europe, the floral diversity began decreasing even before the climatic maximum. Paleogeography played large roles in this diversity decrease. In western Europe, terrestrial floras were on islands and peninsulas in the sea, so that the floras underwent increasing isolation and partial local extermination. Temperate plants generally did not migrate to western Europe, because of a lack of nearby uplands, lack of northern terrestrial source areas for these plants, and presence of the Turgai Straights barrier. The Eocene climate of western Europe cooled at least partly because of decreasing contact with the warm Tethys Seaway.

Historical Biology↗

Investigation of wind and water level for the Giacomini Wetland Restoration Project, Point Reyes National Seashore

Point Reyes National Seashore (PRNS), comprising unique elements of geological, biological, and historical interest, is located on the central California coast approximately 60 km northwest of San Francisco. The National Seashore contains nearly 130 km of exposed and protected shorelines, spectacular coastal cliffs and headlands, lagoons, open grasslands, bushy hillsides, and forested ridges. Approximately 30 km of the shoreline are coastal-dune habitat that supports 11 federally listed species, including the threatened western snowy plover and the endangered plants Tidestrom's lupine ( Lupinus tidestromii ) and beach layia ( Layia carnosa ). The San Andreas Fault, a right-lateral strike-slip fault, trends northwest along the northeastern side of the park. Tomales Bay, which is straight, long, narrow, and shallow, runs along the northeastern boundary of PRNS. The Bay, which fills the northwestern end of a rift valley at the intersection of the San Andreas Fault with the coastline, is approximately 20 km long, 2 km wide, and 6 m deep with mountainous terrain to the southwest and rolling hills to the northeast. Tomales Bay is one of the cleanest estuaries on the West Coast. In winter, approximately 17,000 to 20,000 shorebirds inhabit Tomales Bay and Bodega Bay, which lies directly to the north. At the head of Tomales Bay, the Giacomini Ranch comprises 563 acres of pastureland currently being used for grazing dairy cattle. After more than 50 years of operation as a dairy, the National Park Service acquired the Giacomini property with the intention to restore most of it and the nearby Olema Marsh to tidal wetland. Restoration will add approximately 4% to the existing coastal wetlands in California. The project will return the headwaters of Tomales Bay and two major stream intersections to an intertidal marsh environment, enhancing habitat for both wildlife and fish populations and contributing to the long-term health of Tomales Bay. Prior to the establishment of the ranch, the area was primarily salt marsh that formed as the delta of Lagunitas Creek expanded into Tomales Bay. In converting the salt marsh to dairy land, levees and tide gates were constructed to prevent tidal incursion and stream flooding. Those levees have significantly altered the patterns of estuarine circulation and sediment deposition. To restore natural hydrologic processes within the area and to promote the return of ecological functions and processes, the levees will have to be breached or removed. Developing a successful restoration strategy requires knowledge of elevations within the pastureland and the range of water depths that can be expected from tidal, river, and wind action. In support of the restoration program, the USGS provides technical assistance to PRNS in the form of a scientific study focusing on understanding the physical processes that could affect the Giacomini wetland restoration. The study will yield scientific products that NPS resource managers can use in designing and implementing the restoration project. Research elements include: - Develop a Geodetic Control Network (GCN) throughout PRNS that meets the standards specified National Geodetic Survey data base (the NGS "Bluebook"). The grid will allow this and future studies to be conducted to a precision commensurate with the expressed goals of PRNS. The survey will consist of three steps: (1) verify existing GPS control monuments in the area; (2) tie control monuments in the study areas to the GPS control monuments; and (3) establish NAVD88 elevations using a digital electronic level. - Conduct a detailed survey of the Giacomini site to produce an accurate topographic map of the property. The site survey can be coupled with on-site water-level measurements to produce an empirical flooding model. - Measure water level and wind regime at the Giacomini site. The water-level range is critical to determining the wetland types based on the elevation of the dairy land. Water level at Sacramento Landing, in central Tomales Bay, will also be measured for comparison. As of November 2005, we have created a GCN, produced a detailed topographic map of the Giacomini site, and collected approximately three years of water-level and wind data at the Giacomini site and over one year of usable water-level data at the Sacramento Landing pier.

California↗

Ecology and biology of paddlefish in North America: historical perspectives, management approaches, and research priorities

Paddlefish ( Polyodon spathula , Polyodontidae)are large, mostly-riverine fish that once were abundant in medium- to large-sized river systems throughout much of the central United States. Concern for paddlefish populations has grown from a regional fisheries issue to one of national importance for the United States. In 1989, the U.S. Fish and Wildlife Service (USFWS) was petitioned to list paddlefish as a federally threatened species under the Endangered Species Act. The petition was not granted, primarily because of a lack of empirical data on paddlefish population size, age structure, growth, or harvest rates across the present 22-state range. Nonetheless, concern for paddlefish populations prompted the USFWS to recommend that paddlefish be protected through the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The addition of paddlefish to Appendix II of CITES, which was approved in March 1992, provides a mechanism to curtail illegal trade in paddlefish and their parts and supports a variety of conservation plans. Paddlefish populations have been negatively affected by overharvest, river modifications, and pollution, but the paddlefish still occupies much of its historic range and most extant populations seem to be stable. Although many facets of paddlefish biology and ecology are well understood, the lack of information on larval and juvenile ecology, mechanisms that determine recruitment, population size and vital rates, interjurisdictional movements, and the effects of anthropogenic activities present significant obstacles for managing paddlefish populations. Questions about the size and structure of local populations, and how such populations are affected by navigation traffic, dams, and pollution are regarded as medium priority areas for future research. The availability of suitable spawning habitat and overall reproductive success in impounded rivers are unknown and represent critical areas for future research. Research on reproductive and recruitment success in impounded rivers have significant implications for managing paddlefish, as rivers are modified further for human use.

Reviews in Fish Biology and Fisheries↗

Genetic signatures of historical dispersal of fish threatened by biological invasions: the case of galaxiids in South America

Aim The ecological effects of biological invasions are well documented, but little is known about the effects of invaders on the genetic structure of native species. We examined the phylogeography, genetic variation and population structuring of two galaxiid fishes, Aplochiton zebra and A. taeniatus , threatened by non-native salmonids, and whose conservation is complicated by misidentification and limited knowledge of their genetic diversity. Location Chile and the Falkland Islands. Methods We combined microsatellite and mitochondrial DNA (16S rDNA and COI) markers to compare genetic diversity, effective population size and gene flow of Aplochiton spp. populations differentially affected by salmonid presence. Results We identified two 16S rDNA haplotypes among A. zebra – one dominant in coastal populations and another dominant in inland populations. Populations living on the island of Chiloé displayed a mixture of coastal and inland haplotypes, as well as high microsatellite diversity, as one would expect if the island had been a refugium during the Last Glacial Maximum, or a contact zone among populations. Microsatellite data revealed strong population structuring, indicative of current isolation patterns, and a negative correlation between the genetic diversity of A. zebra and the relative abundance of invasive salmonids. Main conclusions Our study indicates that population structuring of A. zebra reflects the influence of historical patterns of migration, but also the current levels of reduced gene flow among watersheds. Invasive salmonids, known to compete with and prey on native galaxiids, may have had negative impacts on the genetic diversity of Aplochiton spp. The low genetic variation found in some populations, coupled with potential biases in abundance estimates due to species misidentification, highlight the urgent need for more research into the conservation status of the two species of Aplochiton .

Journal of Biogeography↗

Effects of postfire climate and seed availability on postfire conifer regeneration

Large, severe fires are becoming more frequent in many forest types across the western United States and have resulted in tree mortality across tens of thousands of hectares. Conifer regeneration in these areas is limited because seeds must travel long distances to reach the interior of large burned patches and establishment is jeopardized by increasingly hot and dry conditions. To better inform postfire management in low elevation forests of California, USA, we collected 5‐year postfire recovery data from 1,234 study plots in 19 wildfires that burned from 2004–2012 and 18 years of seed production data from 216 seed fall traps (1999–2017). We used this data in conjunction with spatially extensive estimates of climate, topography, forest composition, and burn severity to construct taxon‐specific, spatially explicit models of conifer regeneration that incorporate estimated climate conditions and seed availability during postfire recovery windows. We found that after accounting for other predictors both postfire and historical precipitation were strong predictors of regeneration, suggesting that both direct effects of postfire moisture conditions and biological inertia from historical climate may play a role in regeneration. Alternatively, postfire regeneration may simply be driven by postfire climate and apparent relationships with historical climate could be spurious. The estimated sensitivity of regeneration to postfire seed availability was strongest in firs and all conifers combined and weaker in pines. Seed production exhibited high temporal variability with seed production varying by over two orders of magnitude among years. Our models indicate that during droughts postfire conifer regeneration declines most substantially in low‐to‐moderate elevation forests. These findings enhance our mechanistic understanding of forecasted and historically documented shifts in the distribution of trees.

California↗

Microsatellite DNA variation Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and cross-species amplification the Acipenseridae

O verharvest and habitat alteration have led to a collapse of most commercial Atlantic sturgeon( Acipenser oxyrinchus oxyrinchus )fisheries while pushing the species to rarity or extirpation in most of its historical range. A biologically sound conservation program for this species requires knowledge of its genetic diversity and of the evolutionary relationships among geographic populations. To address these research needs, six microsatellite loci were isolated from A. o. oxyrinchus . Pedigree analysis suggested that all are inherited in a codominant Mendelian pattern. The six loci were tested in ten additional sturgeon species from three genera and three apparent ploidy levels (4n, 8n, 16n). Approximately 70% of successful locus-species amplifications were polymorphic. Polysomy was observed most often in 8n and 16n species. Genetic diversity and population structure of A. o. oxyrinchus were assayed using three polymorphic Aox markers and four markers developed from lake sturgeon ( A. fulvescens ). A. o. oxyrinchus were sampled from the Altamaha River, Georgia, USA north to the St. Lawrence River, Quebec, Canada. Gulf sturgeon, A. o. desotoi , were sampled from the Suwannee River, Florida, USA, to assess differentiation between the subspecies. Seventy-seven alleles were observed to segregate into unique multilocus genotypes for each of the 392 individuals assayed. Mean diversity was greatest in the Chesapeake Bay (9.7 alleles per locus) and Delaware River (7.4 alleles per locus) collections, and lowest in the St. Lawrence River (4.6 alleles per locus). Mean heterozygosity across seven loci ranged from 44.3% (St. Lawrence River) to 62.6% (Altamaha River). Significant allelic heterogeneity was observed in 82% of pairwise comparisons as well as a global test (p < 0.0001) for A. o. oxyrinchus collections. Genetic distance suggests the presence of at least six subpopulations in A. o. oxyrinchus : St. Lawrence River, St. John River, Hudson River, Delaware River, Albemarle Sound, and Altamaha River. Genetic and geographic distances were positively correlated (r = 0.57, p < 0.03) among A. o. oxyrinchus , suggesting isolation by distance and philopatry. Hierarchical gene diversity analysis indicated significant genetic population structure at every level. Maximum likelihood assignment tests correctly assigned individual fish to collection with a high rate of success (mean = 87.5%); this and other lines of evidence indicated that the Chesapeake Bay collection represents a mixed population of sub-adult sturgeon from northern and southern Atlantic coast populations. Population structure was correlated with that suggested by earlier mitochondrial (mt) DNA analyses. Significant diversity was observed between two Canadian populations from which only a single mt DNA haplotype has been reported.

Conservation Genetics↗

Galliform exclusion from the Migratory Bird Treaty Act has produced an alternate conservation path, but no evidence for differences in population status

The Migratory Bird Treaty Act (MBTA) is critical to avian conservation in the United States, both through its protection of migratory birds and as a catalyst for a century of coordinated avian conservation. While more than 1,000 species are protected by MBTA, of extant bird species native to the continental U.S., only 20 species belonging to the order Galliformes are explicitly excluded. Management of galliforms has occurred largely without direct federal oversight, placing this group on a fundamentally different conservation path during the century following MBTA passage. In this paper, we review the historical context and biological justification for exclusion of galliforms from MBTA and synthesize how their present-day conservation differs from that of migratory birds. We find the most prominent difference between the two groups involves the scope of coordination among stakeholders. The U.S. government, primarily via the Department of Interior, acts as de facto coordinating body for migratory bird conservation and plays the central role in oversight, funding, and administration of management in the United States. In contrast, galliform management falls primarily to individual state wildlife agencies, and coordinated conservation efforts have been more ad hoc and unevenly spread across species. Migratory birds benefit from an almost universally greater scope of research and monitoring, scale of habitat conservation, and sophistication of harvest management compared with galliforms. Galliform harvest management plans, in particular, are less likely to use measurable objectives, reporting of uncertainty in population parameters, and explanation of harvest management techniques. Based on a review of species status lists (e.g., the U.S. Endangered Species Act), we found no evidence that galliforms were more frequently listed than migratory species. Regional trend estimates from the North American Breeding Bird Survey (BBS) were more likely to be negative for galliforms over the period 1966–2015, but this was primarily driven by Northern Bobwhite ( Colinus virginianus ). Data to assess galliform population status are generally poor, which complicates assessment for roughly half of galliform species. Increased support for coordination among state agencies and other stakeholders, similar to that applied to migratory birds, could help to ensure that galliform conservation is poised to tackle forthcoming challenges associated with global change.

North America↗

Historical changes in the Columbia River estuary based on sediment cores: feasibility studies

The importance of the Columbia River estuary to salmon, other fishes, migratory birds, and other species is fairly well established. Relatively little is known, however, about long-term, historic variations in biological processes and conditions within the estuary. For example, have conditions varied greatly with climatic regime shifts and how has dam construction on the Columbia River influenced biological communities over time? We conducted a feasibility study to see if sediment cores from the estuary could be aged and whether biological or contaminant indicators could be identified. Such information could be useful in understanding long-term environmental variation and in restoration studies.

Oregon, Washington↗

Trends in nonindigenous aquatic species richness in the United States reveal shifting spatial and temporal patterns of species introductions

Understanding the spatial and temporal dynamics underlying the introduction and spread of nonindigenous aquatic species (NAS) can provide important insights into the historical drivers of biological invasions and aid in forecasting future patterns of nonindigenous species arrival and spread. Increasingly, public databases of species observation records are being used to quantify changes in NAS distributions across space and time, and are becoming an important resource for researchers, managers, and policy-makers. Here we use publicly available data to describe trends in NAS introduction and spread across the conterminous United States over more than two centuries of observation records. Available data on first records of NAS reveal significant shifts in dominance of particular introduction patterns over time, both in terms of recipient regions and likely sources. These spatiotemporal trends at the continental scale may be subject to biases associated with regional variation in sampling effort, reporting, and data curation. We therefore also examined two additional metrics, the number of individual records and the spatial coverage of those records, which are likely to be more closely associated with sampling effort. Our results suggest that broad-scale patterns may mask considerable variation across regions, time periods, and even entities contributing to NAS sampling. In some cases, observed temporal shifts in species discovery may be influenced by dramatic fluctuations in the number and spatial extent of individual observations, reflecting the possibility that shifts in sampling effort may obscure underlying rates of NAS introduction.

Aquatic Invasions↗

Vascular Plant and Vertebrate Inventory of Tumacacori National Historical Park

Executive Summary This report summarizes the results of the first comprehensive biological inventory of Tumacacori National Historical Park (NHP) in southern Arizona. These surveys were part of a larger effort to inventory vascular plants and vertebrates in eight National Park Service units in Arizona and New Mexico. From 2000 to 2003 we surveyed for vascular plants and vertebrates (fish, amphibians, reptiles, birds, and mammals) at Tumacacori NHP to document presence of species within the administrative boundaries of the park's three units. Because we used repeatable study designs and standardized field techniques, these inventories can serve as the first step in a long-term monitoring program. We recorded 591 species at Tumacacori NHP, significantly increasing the number of known species for the park (Table 1). Species of note in each taxonomic group include: * Plants: second record in Arizona of muster John Henry, a non-native species that is ranked a 'Class A noxious weed' in California; * Amphibian: Great Plains narrow-mouthed toad; * Reptiles: eastern fence lizard and Sonoran mud turtle; * Birds: yellow-billed cuckoo, green kingfisher, and one observation of the endangered southwestern willow flycatcher; * Fishes: four native species including an important population of the endangered Gila topminnow in the Tumacacori Channel; * Mammals: black bear and all four species of skunk known to occur in Arizona. We recorded 79 non-native species (Table E.S.1), many of which are of management concern, including: Bermudagrass, tamarisk, western mosquitofish, largemouth bass, bluegill, sunfish, American bullfrog, feral cats and dogs, and cattle. We also noted an abundance of crayfish (a non-native invertebrate). We review some of the important non-native species and make recommendations to remove them or to minimize their impacts on the native biota of the park. Based on the observed species richness, Tumacacori NHP possesses high biological diversity of plants, fish, and birds for a park of its size. This richness is due in part to the ecotone between ecological provinces (Madrean and Sonoran), the geographic distribution of the three units (23 km separates the most distant units), and their close proximity to the Santa Cruz River. The mesic life zone along the river, including rare cottonwood/willow forests and adjacent mesquite bosque at the Tumacacori unit, is representative of areas that have been destroyed or degraded in many other locations in the region. Additional elements such as the semi-desert grassland vegetation community are also related to high species richness for some taxonomic groups. This report includes lists of species recorded by us (or likely to be recorded with additional effort) and maps of study sites. We also suggest management implications and ways to maintain or enhance the unique biological resources of Tumacacori NHP: limit development adjacent to the park, exclude cattle and off-road vehicles, develop an eradication plan for non-native species, and hire a natural resource specialist. These recommendations are intended to assist park staff with addressing many of the goals set out in their most recent natural resources management plan. This study is the first step in a long-term process of compiling information on the biological resources of Tumacacori NHP and its surrounding areas, and our findings should not be viewed as the final authority on the plants and animals of the park. Therefore, we also recommend additional inventory and monitoring studies and identify components of our effort that could be improved upon, either through the application of new techniques (e.g., use of genetic markers) or by extending the temporal and/or spatial scope of our research.

Open-File Report↗

Stories in stone: The geoheritage significance of U.S. National Park Service stratotypes

The U.S. National Park Service stratotype inventory has systematically documented hundreds of published stratotypes across the country that represent a quintessential component of America’s geoheritage and possess significant scientific, educational, cultural, historic, and aesthetic values. As valuable geologic reference standards, stratotypes record intervals of Earth history relating to our nation’s unique geologic evolution, biological progression, cultural traditions, historical narratives, and stunning landforms. However, the general lack of awareness and knowledge regarding the scope, significance, distribution, and scale of stratotypes can result in these resources being overlooked. Consequently, stratotypes may inadvertently experience accidental alteration, damage, or destruction through both natural and anthropogenic processes. As with many American geoheritage sites, stratotypes lack specific recognition through legislation, policies, or other management strategies to ensure their preservation and protection. Through education and outreach, we hope to inform, increase awareness, and engage the public about these internationally and nationally significant geologic reference sites, unite various geoheritage communities, and promote their preservation for future generations.

Geoheritage↗

Selecting habitat management strategies on refuges

This report is a joint effort of the Biological Resources Division, U.S. Geological Survey and the U.S. Fish and Wildlife Service (FWS) to provide National Wildlife Refuge (NWR) managers guidance on the selection and evaluation of habitat management strategies to meet stated objectives. The FWS recently completed a handbook on writing refuge management goals and objectives (U.S. Fish and Wildlife Service 1996a). the National Wildlife Refuge System Improvement Act of 1997 requires that National Wildlife Refuge System (NWRS) lands be managed according to approved Comprehensive Conservation Plans to guide management decisions and devise strategies for achieving refuge unit purposes and meeting the NWRS mission. It is expected that over the next several years most refuges will develop new or revised refuge goals and objectives for directing their habitat management strategies. This paper outlines the steps we recommend in selecting and evaluating habitat management strategies to meet specific refuge habitat objectives. We selected two examples to illustrate the process. Although each refuge is unique and will require specific information and solutions, these two examples can be used as guidance when selecting and evaluating habitat management strategies for other refuge resources: Example 1. Management of floodplain woods habitat for forest interior birds. The biological recourse of concern is the quality and quantity of floodplain woods habitat for eastern forest interior birds in the Cypress Creek NWR (U.S. Fish and Wildlife Service 1996b). Example 2. Management of habitat for biodiversity: Historical landscape proportions. The biological resource of concern is the change in diversity associated with man-induced changes in the distribution and abundance of habitat types at the Minnesota Valley NWR (U.S. Fish and Wildlife Service 1996c).

Information and Technology Report↗

Phenological flexibility in nesting grassland birds over a half century informs timing of management

The timing of biological events for wildlife species reflects and influences ecological and evolutionary processes and helps guide management actions to meet conservation objectives. Climate change may cause phenological shifts across trophic levels and ecosystems, which can have broad ecological impacts. Shifts may also result in mistiming between management practices based on historical conditions and current biological events, reducing the effectiveness of natural resource management and conservation efforts. We analyzed nesting phenology patterns over recent decades across North America for 44 species of grassland-nesting birds, including waterfowl, upland gamebirds, shorebirds, and passerines, many of which have experienced precipitous population declines. Understanding nesting phenologies of these species is important to their conservation, as grassland management activities often conflict with reproductive periods leading to high nest and young mortality. We compiled a dataset of over 172,000 nest records spanning five decades and evaluated environmental factors influencing long-term shifts and short-term flexibility in nesting phenology. We found considerable variation in responses among species, with differences in both direction and magnitude of spatiotemporal effects on nest initiation dates. Notably, the community-level nesting season lengthened over time, but shifts exhibited spatial heterogeneity within this community of grassland birds. Nesting dates shifted asymmetrically across the breeding season with differential changes in early, peak, and late nesting dates whereas long-term changes were mediated by weather and geographic gradients. For example, nest initiation was earlier in warmer and wetter years. By applying a quantile-based analysis, we provide estimates of the full nesting period that could serve as a flexible tool for scheduling monitoring efforts and balancing management and human activities with periods of reduced nesting activity. Our collaborative effort illustrates the challenges and opportunities of collecting long-term data on avian communities necessary for answering questions across large regions but highlights the value of research coordination for bird conservation.

Global Change Biology↗