Reports & Documents
Plan for the Population Restoration and Conservation of Imperiled Freshwater Mollusks of the Cumberland Region
The goal of this Plan is to provide a framework for the restoration of freshwater mollusk resources and their ecological functions to appropriate reaches of the Cumberlandian Region through the reintroduction, augmentation (R/A) and controlled propagation of priority mollusks. The Plan prioritizes propagation and R/A activities for Region mollusks and provides guidelines for resource managers and recovery partners. The Plan is not a legal document and is not intended to replace or supersede published recovery plans for listed mollusks.
Conservation in the face of climate change: The roles of alternative models, monitoring, and adaptation in confronting and reducing uncertainty
The broad physical and biological principles behind climate change and its potential large scale ecological impacts on biota are fairly well understood, although likely responses of biotic communities at fine spatio-temporal scales are not, limiting the ability of conservation programs to respond effectively to climate change outside the range of human experience. Much of the climate debate has focused on attempts to resolve key uncertainties in a hypothesis-testing framework. However, conservation decisions cannot await resolution of these scientific issues and instead must proceed in the face of uncertainty. We suggest that conservation should precede in an adaptive management framework, in which decisions are guided by predictions under multiple, plausible hypotheses about climate impacts. Under this plan, monitoring is used to evaluate the response of the system to climate drivers, and management actions (perhaps experimental) are used to confront testable predictions with data, in turn providing feedback for future decision making. We illustrate these principles with the problem of mitigating the effects of climate change on terrestrial bird communities in the southern Appalachian Mountains, USA.
Six Common Mistakes in Conservation Priority Setting
A vast number of prioritization schemes have been developed to help conservation navigate tough decisions about the allocation of finite resources. However, the application of quantitative approaches to setting priorities in conservation frequently includes mistakes that can undermine their authors’ intention to be more rigorous and scientific in the way priorities are established and resources allocated. Drawing on well-established principles of decision science, we highlight 6 mistakes commonly associated with setting priorities for conservation: not acknowledging conservation plans are prioritizations; trying to solve an ill- defined problem; not prioritizing actions; arbitrariness; hidden value judgments; and not acknowledging risk of failure. We explain these mistakes and offer a path to help conservation planners avoid making the same mistakes in future prioritizations.
Toward rigorous use of expert knowledge in ecological research
Practicing ecologists who excel at their work (‘‘experts’’) hold a wealth of knowledge. This knowledge offers a wide range of opportunities for application in ecological research and natural resource decision-making. While experts are often consulted ad-hoc, their contributions are not widely acknowledged. These informal applications of expert knowledge lead to concerns about a lack of transparency and repeatability, causing distrust of this knowledge source in the scientific community. Here, we address these concerns with an exploration of the diversity of expert knowledge and of rigorous methods in its use. The effective use of expert knowledge hinges on an awareness of the spectrum of experts and their expertise, which varies by breadth of perspective and critical assessment. Also, experts express their knowledge in different forms depending on the degree of contextualization with other information. Careful matching of experts to application is therefore essential and has to go beyond a simple fitting of the expert to the knowledge domain. The standards for the collection and use of expert knowledge should be as rigorous as for empirical data. This involves knowing when it is appropriate to use expert knowledge and how to identify and select suitable experts. Further, it requires a careful plan for the collection, analysis and validation of the knowledge. The knowledge held by expert practitioners is too valuable to be ignored. But only when thorough methods are applied, can the application of expert knowledge be as valid as the use of empirical data. The responsibility for the effective and rigorous use of expert knowledge lies with the researchers.
Three new darter species of the Etheostoma percnurum species complex (Percidae, subgenus Catonotus) from the Tennessee and Cumberland River Drainages
The federally endangered Duskytail Darter, Etheostoma percnurum Jenkins, is known from only six highly disjunct populations in the Tennessee and Cumberland river drainages of Kentucky, Tennessee, and Virginia. Only four are extant. Variation in morphology including meristics, morphometrics, and pigmentation was examined among the four extant populations and limited specimens from the two extirpated populations (Abrams Creek and South Fork Holston River). Analyses of these data found each of the extant populations is morphologically diagnosable. The few specimens avail- able from Abrams Creek and South Fork Holston River prevented thorough assessment of variation, and these were grouped with their closest geographic counterparts, Citico Creek, and Little River, respectively. Three new morphologi- cally diagnosable species are described: E. sitikuense, the Citico Darter, from Citico Creek, Abrams Creek, and Tellico River (Tennessee River system); E. marmorpinnum, the Marbled Darter, from the Little River and South Fork Holston River (Tennessee River system); and E. lemniscatum, the Tuxedo Darter, from the Big South Fork (Cumberland River system). Each species warrants federal protection as an endangered species.
Population Performance Criteria to Evaluate Reintroduction and Recovery of Two Endangered Mussel Species, Epioblasma brevidens and Epioblasma capsaeformis
Genetic and demographic modeling of two endangered mussel species, Epioblasma brevidens and E. capsaeformis, in the Clinch River, U.S.A., was conducted to determine quantitative criteria to evaluate performance of extant and reintroduced populations. Reintroduction modelling indicated that the initial population size created during a 5 year build-up phase greatly affected final population size at 25 years, being similar to the population size at the end of the build-up phase, especially when population growth rate was low. Excluding age 0 individuals, age 1 juveniles or recruits on average comprised approximately 11% and 15% of a stable population of each species, respectively. Age-class distribution of a stable or growing population was characterized by multiple cohorts, including juvenile recruits, sub-adults, and adults. Because of current barriers to dispersal and the low dispersal capability of some mussel species, reintroductions will play a prominent role in restoring populations in the United States.
Hydrologic Units within the Tennessee River Basin
Unit name and total area (square miles) for 2, 4, 6, and 8 digit hydrologic units within the Tennessee River System.
