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Establishing an analytical framework for calculating consistent and sensitive measures of the rate of biodiversity change

The Convention on Biological Diversity’s (CBD) VIth Conference of the Parties (COP) and the World Summit on Sustainable Development agreed to a target to achieve a significant reduction of the rate of biodiversity loss by 2010. The VIIth COP adopted a conceptual framework to facilitate the assessment of global progress toward 2010 and to encourage national and regional targets and indicators. However, most of the indicators identified are not and will not be adequately quantified at desired accuracy and with desired frequency by 2010. What is possible is the establishment of an analytic framework that can provide guidelines and baselines for biodiversity estimates that can steadily improve with time. A judicious combination of remotely sensed data, Geographic Information System data, ground samples, and expert knowledge of species trends and species’ use of habitats form a solid basis for assessing biodiversity. National development of sensitive, consistent, and affordable indicators that can contribute to the CBD global indicators requires access to a baseline set of global ecosystem, climate, topography, land cover, and human impact information. Fortunately, over the last ten years, a number of relevant information sources have become available. Such information, as well as appropriate methods for use, should be promoted and made highly accessible to countries and organizations that support the CBD. The NASA-Non-Governmental Organization (NGO) Conservation Working Group is collaborating to evaluate and demonstrate the meaningful role remote sensing can play in developing biodiversity indicators to meet the targets specified. The Working Group members are evaluating indicators across a range of biomes and scales. The results are being synthesized in a handbook describing the use of remote sensing for monitoring the 2010 target to be published in 2006.

Conference Paper

Mammalian resistance to megafire in western U.S. woodland savannas

Increasingly frequent megafires are dramatically altering landscapes and critical habitats around the world. Across the western United States, megafires have become an almost annual occurrence, but the implication of these fires for the conservation of native wildlife remains relatively unknown. Woodland savannas are among the world's most biodiverse ecosystems and provide important food and structural resources to a variety of wildlife, but they are threatened by megafires. Despite this, the great majority of fire impact studies have only been conducted in coniferous forests. Understanding the resistance and resilience of wildlife assemblages following these extreme perturbations can help inform future management interventions that limit biodiversity loss due to megafire. We assessed the resistance of a woodland savanna mammal community to the short-term impacts of megafire using camera trap data collected before, during, and after the fire. Specifically, we utilized a 5-year camera trap data set (2016–2020) from the Hopland Research and Extension Center to examine the impacts of the 2018 Mendocino Complex Fire, California's largest recorded wildfire at the time, on the distributions of eight observed mammal species. We used a multispecies occupancy model to quantify the effects of megafire on species' space use, to assess the impact on species size and diet groups, and to create robust estimates of fire's impacts on species diversity across space and time. Megafire had a negative effect on the detection of certain mammal species, but overall, most species showed high resistance to the disturbance and returned to detection and site use levels comparable to unburned sites by the end of the study period. Following megafire, species richness was higher in burned areas that retained higher canopy cover relative to unburned and burned sites with low canopy cover. Fire management that prevents large-scale canopy loss is critical to providing refugia for vulnerable species immediately following fire in oak woodlands, and likely other mixed-forest landscapes.

California

Beaver dams maintain fish biodiversity by increasing habitat heterogeneity throughout a low-gradient stream network

Understanding the relationship between heterogeneity and biodiversity is an active focus of ecological research. Although habitat heterogeneity is conceptually linked to biodiversity, the amount and configuration of heterogeneity that maintains biodiversity within ecosystems is not well understood, especially for an entire stream network. Here, we tested alternative outcomes about how habitat alterations caused by beaver dams affected native fish biodiversity. Specifically, we quantified in-stream habitat and fish assemblages above and below all beaver dams ( n = 15) and selected control sites ( n = 9), adjacent to beaver dams, within an entire, low-gradient stream network (Fish Brook, MA, U.S.A.). Beaver dams altered habitat within streams in four ways based on upstream versus downstream differences in stream width, depth, velocity and substratum. In general, habitat heterogeneity, measured using two indices, was greater at beaver dams than control sites. The diversity and abundance of fish around beaver dams were positively related to habitat heterogeneity. Faster water and the coarser substratum below beaver dams increased the amount of fluvial habitat available to native fish. This alteration can be critical for fish with life histories that depend on flowing water and hard substrata. In summary, within a stream network, beaver dams maintained fish biodiversity by altering in-stream habitat and increasing habitat heterogeneity. Understanding the relationship between habitat heterogeneity and biodiversity can advance basic freshwater ecology and provide science-based support for applied aquatic conservation

Massachusetts

Positive biodiversity-productivity relationship predominant in global forests

The relationship between biodiversity and ecosystem productivity has been explored in detail in herbaceous vegetation, but patterns in forests are far less well understood. Liang et al. have amassed a global forest data set from >770,000 sample plots in 44 countries. A positive and consistent relationship can be discerned between tree diversity and ecosystem productivity at landscape, country, and ecoregion scales. On average, a 10% loss in biodiversity leads to a 3% loss in productivity. This means that the economic value of maintaining biodiversity for the sake of global forest productivity is more than fivefold greater than global conservation costs.

Science

People need freshwater biodiversity: Nine reasons freshwater biodiversity is important for humans

Freshwater biodiversity, from fish to frogs and microbes to macrophytes, provides a vast array of services to people. These services are under a growing threat as human-related pressure threatens freshwater biodiversity on multiple fronts. Here, Abigail Lynch and colleagues discuss nine fundamental ecosystem services that freshwater biodiversity provide to people. Given the importance of freshwater biodiversity to our very existence, they make a plea for a redoubled effort to better conserve this precious resource.

Global Water Forum

Southeastern freshwater fishes

North America has the richest fauna of temperate freshwater fishes in the world, with about 800 native species in the waters of Canada and the United States. The center of this diversity is in the southeastern United States, where as many as 500 species may exist (62% of the continental fauna north of Mexico). Many coastal marine species also enter fresh waters of the Southeast, and at least 34 foreign fish species are established in the region. Although freshwater fishes of the United States are better studied than any fish fauna of comparable scope in the world (Lee et al. 1980; Hocutt and Wiley 1986; Matthews and Heins 1987; Page and Burr 1991; Mayden 1992), large gaps exist in scientific knowledge about the biology and ecology of most species. New species are still being discovered, and the taxonomy of other species is being refined. Seriously declining populations of freshwater fishes in the United States concern the scientific community (Deacon et al. 1979; Williams et al. 1989; Moyle and Leidy 1992; Warren and Burr 1994). This article briefly summarizes the current conservation status of southeastern freshwater fishes; the Southeast is emphasized because of its important fish biodiversity and to focus attention on the growing problem of adverse human impacts on the region's aquatic habitats (Mount 1986; Burkhead and Jenkins 1991; Etnier and Starnes 1991; Warren and Burr 1994).

Book chapter

It is the time for oceanic seabirds: Tracking year-round distribution of gadfly petrels across the Atlantic Ocean

Aim Anthropogenic activities alter and constrain the structure of marine ecosystems with implications for wide-ranging marine vertebrates. In spite of the environmental importance of vast oceanic ecosystems, most conservation efforts mainly focus on neritic areas. To identify relevant oceanic areas for conservation, we assessed the year-round spatial distribution and spatio-temporal overlap of eight truly oceanic seabird species of gadfly petrels ( Pterodroma spp.) inhabiting the Atlantic Ocean. Location Atlantic Ocean. Methods Using tracking data (mostly from geolocators), we examined year-round distributions, the timing of life-cycle events, and marine habitat overlap of eight gadfly petrel species that breed in the Atlantic Ocean. Results We compiled 125 year-round tracks. Movement strategies ranged from non-migratory to long-distance migrant species and from species sharing a common non-breeding area to species dispersing among multiple non-breeding sites. Gadfly petrels occurred throughout the Atlantic Ocean but tended to concentrate in subtropical regions. During the boreal summer, up to three species overlapped spatio-temporally over a large area around the Azores archipelago. During the austral summer, up to four species coincided in a core area in subtropical waters around Cape Verde, and three species shared habitat over two distinct areas off Brazil. The petrels used many national Exclusive Economic Zones, although they also exploited offshore international waters. Main conclusions Tracking movements of highly mobile vertebrates such as gadfly petrels can provide a powerful tool to evaluate and assess the potential need for and location of protected oceanic areas. As more multispecies, year-round data sets are collected from wide-ranging vertebrates, researchers and managers will have greater insight into the location of biodiversity hotspots. These can subsequently inform and guide marine spatial planning efforts that account for both conservation and sustainable use of resources such as commercial fisheries.

Diversity and Distributions

Using predictions from multiple anthropogenic threats to estimate future population persistence of an imperiled species

Imperiled species face numerous and diverse anthropogenic threats to their persistence, and wildlife managers charged with making conservation decisions benefit from a sound understanding of how populations, species, and ecosystems will respond to future changes in threats to biodiversity. In southeastern North America, the gopher tortoise ( Gopherus polyphemus ) is a keystone species in upland ecosystems; however, tortoise populations have declined strongly over the last century, and the species is a candidate for increased protection by the United States federal government under the Endangered Species Act (ESA). Here, we sought to support conservation decision making for G. polyphemus by developing a spatially-explicit predictive population model that linked four anthropogenic threats (climate warming, sea-level rise, urbanization, habitat degradation) to demographic vital rates and used the model to estimate future changes in the number of individuals, populations, and metapopulations across the species’ range. Using recent survey data, we projected 457 populations for 80 years into the future under scenarios varying in threat magnitude, management magnitude, and demographic uncertainty. Population projections predicted that the number of individuals, populations, and metapopulations would decline among all simulated scenarios in the next 80 years. Model predictions were more sensitive to variation in adult survival and immigration rates than to variation in threat magnitude. A scenario with decreased habitat management and threat effects from climate warming, sea-level rise, and urbanization predicted geographic variation in persistence probabilities for populations that might result in decreased genetic representation across the species' range. Our results can be used to support conservation listing decisions for the gopher tortoise as part of its federal Species Status Assessment and provide an analytical framework for how to link diverse threats to geographically-varying demographic rates during population viability analyses for wide-ranging imperiled species around the world.

Global Ecology and Conservation

Reptile and amphibian diversity and abundance in an urban landscape: Impacts of fragmentation and the conservation value of small patches

Urbanization is a major contributor to habitat loss and fragmentation and is considered a global threat to biodiversity. We studied reptile and amphibian species diversity and abundance in a highly fragmented landscape adjacent to the second largest metropolitan area in the United States. Habitat patches in our study area were made up of remnant native vegetation surrounded by roads, housing, and other urban development. Species richness and diversity were positively associated with patch size, but patch age was not significantly associated with community characteristics. Four relatively common species were not detected in the small patches, indicating the possibility they had been extirpated by the time monitoring began, and six rarer species were not detected or detected only once in these patches. Although the patch size effect on species diversity was strong, we found that several of the small habitat patches had similar diversity to large patches, indicating potential value of these small habitat patches in protecting species as “microreserves.” In addition, one lizard species was found to be significantly more abundant in the smaller patches. To determine if abundance changed over time, we compared capture rates for four common lizards at the same sites ten years later. For three of the four species, abundance decreased over that period, specifically in the small patches. Although our long-term monitoring has confirmed that the full suite of herpetofauna is currently preserved in the study area overall, declines even in the common species over time hint at the potential severity of the threat of urbanization to rare species.

California

Organizing phenological data resources to inform natural resource conservation

Changes in the timing of plant and animal life cycle events, in response to climate change, are already happening across the globe. The impacts of these changes may affect biodiversity via disruption to mutualisms, trophic mismatches, invasions and population declines. To understand the nature, causes and consequences of changed, varied or static phenologies, new data resources and tools are being developed across the globe. The USA National Phenology Network is developing a long-term, multi-taxa phenological database, together with a customizable infrastructure, to support conservation and management needs. We present current and potential applications of the infrastructure, across scales and user groups. The approaches described here are congruent with recent trends towards multi-agency, large-scale research and action.

Biological Conservation

Fish diversity, endemism, threats, and conservation in the Jinsha River basin (upper Yangtze River), China

The Jinsha River, which comprises the upper reaches of the Yangtze River, has among the highest freshwater fish biodiversity and endemism in China, but these characteristics have rarely been quantitatively evaluated at the basin scale. We used fish presence–absence data collected from the entire Jinsha River basin (JRB) from 1964 to 2017 to determine patterns in fish biodiversity. In total, 229 freshwater fish species from 9 orders, 26 families, and 110 genera were recorded. Of these species, 161 were endemic to China, with 94 species being endemic to the Yangtze River basin, and 39 species were threatened. Fish species richness was higher in the downstream river reaches and was higher in the main stem than in the tributaries. Overfishing, water pollution, and dam construction have been threatening fish diversity in the JRB for several decades. Conservation strategies similar to those used in North America may be applicable to the JRB to help protect native fishes in this important river basin. Such strategies include (1) assessment of several tributaries as fish reserves; (2) regular adjustment of turbine operations during the fish spawning period; and (3) regulation of the many co-occurring human stressors in the JRB.

Jinsha River Basin (Upper Yangtze River)

Global commitments to conserving and monitoring genetic diversity are now necessary and feasible

Global conservation policy and action have largely neglected protecting and monitoring genetic diversity—one of the three main pillars of biodiversity. Genetic diversity (diversity within species) underlies species’ adaptation and survival, ecosystem resilience, and societal innovation. The low priority given to genetic diversity has largely been due to knowledge gaps in key areas, including the importance of genetic diversity and the trends in genetic diversity change; the perceived high expense and low availability and the scattered nature of genetic data; and complicated concepts and information that are inaccessible to policymakers. However, numerous recent advances in knowledge, technology, databases, practice, and capacity have now set the stage for better integration of genetic diversity in policy instruments and conservation efforts. We review these developments and explore how they can support improved consideration of genetic diversity in global conservation policy commitments and enable countries to monitor, report on, and take action to maintain or restore genetic diversity.

BioScience

Effect of different sampling schemes on the spatial placement of conservation reserves in Utah, USA

We evaluated the effect of three different sampling schemes used to organize spatially explicit biological information had on the spatial placement of conservation reserves in Utah, USA. The three sampling schemes consisted of a hexagon representation developed by the EPA/EMAP program (statistical basis), watershed boundaries (ecological), and the current county boundaries of Utah (socio-political). Four decision criteria were used to estimate effects, including amount of area, length of edge, lowest number of contiguous reserves, and greatest number of terrestrial vertebrate species covered. A fifth evaluation criterion was the effect each sampling scheme had on the ability of the modeled conservation reserves to cover the six major ecoregions found in Utah. Of the three sampling schemes, county boundaries covered the greatest number of species, but also created the longest length of edge and greatest number of reserves. Watersheds maximized species coverage using the least amount of area. Hexagons and watersheds provide the least amount of edge and fewest number of reserves. Although there were differences in area, edge and number of reserves among the sampling schemes, all three schemes covered all the major ecoregions in Utah and their inclusive biodiversity. ?? 2003 Elsevier Science Ltd. All rights reserved.

Biological Conservation

A risk-based approach to evaluating wildlife demographics for management in a changing climate: A case study of the Lewis's Woodpecker

Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species' response to climate into conservation decisions. This is shown by taking advantage of species' response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifically, we examine the current and potential impact of climate on nest survival of the Lewis's Woodpecker ( Melanerpes lewis ) in two different habitats. To address climate uncertainty, climate scenarios are developed by manipulating historical weather observations to create ensembles (i.e., multiple sequences of daily weather) that reflect historical variability and potential climate change. These ensembles allow for a probabilistic evaluation of the risk posed to Lewis's Woodpecker nest survival and are used in two demographic analyses. First, the relative value of each habitat is compared in terms of nest survival, and second, the likelihood of exceeding a critical population threshold is examined. By embedding the analyses in a risk framework, we show how management choices can be made to be commensurate with a defined level of acceptable risk. The results can be used to inform habitat prioritization and are discussed in the context of an economic framework for evaluating trade-offs between management alternatives.

Idaho

Are hotspots of evolutionary potential adequately protected in southern California?

Reserves are often designed to protect rare habitats, or "typical" exemplars of ecoregions and geomorphic provinces. This approach focuses on current patterns of organismal and ecosystem-level biodiversity, but typically ignores the evolutionary processes that control the gain and loss of biodiversity at these and other levels (e.g., genetic, ecological). In order to include evolutionary processes in conservation planning efforts, their spatial components must first be identified and mapped. We describe a GIS-based approach for explicitly mapping patterns of genetic divergence and diversity for multiple species (a "multi-species genetic landscape"). Using this approach, we analyzed mitochondrial DNA datasets from 21 vertebrate and invertebrate species in southern California to identify areas with common phylogeographic breaks and high intrapopulation diversity. The result is an evolutionary framework for southern California within which patterns of genetic diversity can be analyzed in the context of historical processes, future evolutionary potential and current reserve design. Our multi-species genetic landscapes pinpoint six hotspots where interpopulation genetic divergence is consistently high, five evolutionary hotspots within which genetic connectivity is high, and three hotspots where intrapopulation genetic diversity is high. These 14 hotspots can be grouped into eight geographic areas, of which five largely are unprotected at this time. The multi-species genetic landscape approach may provide an avenue to readily incorporate measures of evolutionary process into GIS-based systematic conservation assessment and land-use planning.

Biological Conservation

Climate-induced forest dieback as an emergent global phenomenon: Organized oral session at the Ecological Society of America/Society of Ecological Restoration Joint Meeting; San Jose, California, 5-10 August 2007

An organized oral session at the annual meeting of the Ecological Society of America in San Jose, Calif., posed this question: Is climate-induced drought stress triggering increasing rates and unusual patterns of forest die-off at a global scale? Twenty-nine researchers representing five continents reported on patterns, mechanisms, and projections of forest mortality. Observations include widespread forest dieback or reductions in tree cover and biodiversity in response to drought and warmer temperatures in the African Sahel (Patrick Gonzalez, The Nature Conservancy), Mediterranean and alpine Europe (Jorge Castro, Universidad de Granada), and Argentinean Patagonia (Thomas Kitzberger, Universidad Nacional del Comahue). In contrast, although much Eucalyptus mortality has resulted from recent droughts in Australia, warming trends have been less pronounced in the Southern Hemisphere and it is unclear if contemporary climate-induced tree mortality differs from previous historical drought impacts (Rod Fensham, Queensland Herbarium).

Eos, Transactions, American Geophysical Union

Wildlife connectivity approaches and best practices in U.S. state wildlife action plans

As habitat loss and fragmentation threaten biodiversity on large geographic scales, creating and maintaining connectivity of wildlife populations is an increasingly common conservation objective. To assess the progress and success of large-scale connectivity planning, conservation researchers need a set of plans that cover large geographic areas and can be analyzed as a single data set. The state wildlife action plans (SWAPs) fulfill these requirements. We examined 50 SWAPs to determine the extent to which wildlife connectivity planning, via linkages, is emphasized nationally. We defined linkage as connective land that enables wildlife movement. For our content analysis, we identified and quantified 6 keywords and 7 content criteria that ranged in specificity and were related to linkages for wide-ranging terrestrial vertebrates and examined relations between content criteria and statewide data on focal wide-ranging species, spending, revenue, and conserved land. Our results reflect nationwide disparities in linkage conservation priorities and highlight the continued need for wildlife linkage planning. Only 30% or less of the 50 SWAPs fulfilled highly specific content criteria (e.g., identifying geographic areas for linkage placement or management). We found positive correlations between our content criteria and statewide data on percent conserved land, total focal species, and spending on parks and recreation. We supplemented our content analysis with interviews with 17 conservation professionals to gain specific information about state-specific context and future directions of linkage conservation. Based on our results, relevant literature, and interview responses, we suggest the following best practices for wildlife linkage conservation plans: collect ecologically meaningful background data; be specific; establish community-wide partnerships; and incorporate sociopolitical and socioeconomic information.

Conservation Biology

Trout in hot water: A call for global action

Trout are one of the most culturally, economically, and ecologically important taxonomic groups of freshwater fishes worldwide (1). Native to all continents in the Northern Hemisphere, trout are a taxonomically diverse group of fishes belonging to 7 genera (Oncorhynchus, Salvelinus, Salmo, Hucho, Parahucho, Brachymystax, and Salvethymus) distributed across 52 countries. These coldwater specialists provide recreation and food to millions of people, and play important roles in ecosystem functioning and health (2). They are also extremely sensitive to human disturbances because they require cold, clean, complex, and connected habitats for survival and persistence (3) – all attributes that humans have substantially altered and degraded (4, 5). Despite their broad importance as societal icons and as indicators of biodiversity, many of the world’s trout species and lineages are endangered and some require immediate conservation efforts to reverse their precarious decline.

Science