The coastrange sculpin, Cottus aleuticus

Master of ScienceFisheriesUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/115055/1/39015003267245.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/115055/2/39015003267245.pd

History Repeats? Hydro Dams and the Riverine Ecosystems of Mesoamerica: The Case of La Amistad Biosphere Reserve, Panama, and its Implications

contribute to fisheries, plus most of the crayfish, were eliminated from six states of the United States. And assume that this and consequent secondary effects on riverine ecosystems, including several large rivers lying within national parks and forests, were documented in the scientific literature. And let us suppose that the blame for this damage could clearly be assigned to a single type of human activity, undertaken without adequate prior consideration of ecosystem effects. Now, imagine that decades into the future the exact same activities were proposed for six more states. It is easy to imagine what comes next: Conservationists rush to the barricades, biologists predict the consequences, volumes of correspondence land on the desks of elected officials and bureaucrats, alternatives are proposed, fundraising campaigns are launched.... The second half of this scenario is being enacted right now, not in the continental United States, but just to the south, and the impact stands to be felt in most of the national parks, biosphere reserves and protected areas of the Mesoamerican isthmus, stretching for over 1,000 miles from Chiapas (Mexico) to the Choco (Colombia). This is what will occur in Mesoamerica if current plans for development of hydropower to industrialize the region in the name of free trade are realized. According to an inventory carried out by Conservation Strategy Fund, there are presently 381 dams proposed for the regio

Mixed Evidence for Biotic Homogenization of Southern Appalachian Fish Communities

Anthropogenic impacts on the landscape can drive biotic homogenization, whereby distinct biological communities become more similar to one another over time. Land-use change in the Southern Appalachian region is expected to result in homogenization of the highly diverse freshwater fish communities as in-stream habitat alterations favor widespread cosmopolitan species at the expense of more narrowly distributed highland endemic species. We compiled four datasets spanning 25 years to (1) evaluate the effects of environmental factors on relative abundance and richness of highland endemic vs. cosmopolitan species in this region and (2) test for taxonomic homogenization, measured as a change in beta diversity over time. We found that several environmental factors differentially affected highland endemic and cosmopolitan species, with the proportion of forested land cover in a watershed most strongly predicting higher relative abundance and richness of highland endemic species. Our analysis of beta diversity change, however, shows mixed evidence of taxonomic homogenization, depending on how common species are weighted. Shifts in community composition, with or without homogenization, may warrant attention in biodiversity conservation planning.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

BioTIME:a database of biodiversity time series for the Anthropocene

Abstract Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community‐led open‐source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene. Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record. Spatial location and grain: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km² (158 cm²) to 100 km² (1,000,000,000,000 cm²). Time period and grain: BioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year. Major taxa and level of measurement: BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates. Software format: .csv and .SQL

Are rare species useful species? Obstacles to the conservation of tree diversity in the dry forest zone agro-ecosystems of Mesoamerica

Aim To test the potential to conserve rare dry forest tree and shrub species circa situm.Location Oaxaca, Mexico and Southern Honduras.Methods Local uses (timber, posts and firewood) of species were determined principally through semistructured interviews with 20 rural householders in each of four communities in Honduras and four in Oaxaca. Tree and shrub diversity inventories were carried out in a total of 227 forest patches and parcels of farmland in those eight communities. Species’ conservation priorities were determined using the star system of Hawthorne (1996) and IUCN listings.Results Despite a large number of useful species, remarkably few were also conservation priorities. Useful species were found to be substitutable as is illustrated by Bombacopsis quinata, Cordia alliodora, Guaiacum sanctum and G. coulteri.Conclusions In these areas, circa situm conservation is inhibited by the lack of species that are both rare and useful. Usefulness must be interpreted as a function of substitutability. Natural regeneration provides an abundance of diversity, farmers are unlikely to invest in the management of a species when suitable substitutes are freely available. The key to conserving rare species may be in maintaining or enhancing the value of the landscape elements in which they are found