Ecology and Evolutionary Biology Commons^™

Chlorophacinone Baiting For Belding’S Ground Squirrels, Craig A. Ramey, George H. Matschke, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

The efficacy of using 0.01% chlorophacinone on steam-rolled oat (SRO) groats applied in CA alfalfa by spot-baiting/hand baiting around burrow entrances (~11.5 g) to control free-ranging Belding's ground squirrels (Spermophilus beldingi) were compared in 6 randomly assigned square treatment units (TUs). Four TUs were given the rodenticide and 2 treated with placebo bait. Each TU was a 0.4 ha square surrounded by a similarly treated 5.5 ha square buffer zone. Baits were applied on May 13 and re-applied, on May 20 and May 22, after 7 days of un-forecasted cool wet weather greatly reduced their above ground activity. Pesticide (EPA …

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …

Eastward Ho: Phylogeographical Perspectives On Colonization Of Hosts And Parasites Across The Beringian Nexus [Guest Editorial], Eric Waltari, Eric P. Hoberg, Enrique P. Lessa, Joseph A. Cook

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The response of Arctic organisms and their parasites to dramatic fluctuations in climate during the Pleistocene has direct implications for predicting the impact of current climate change in the North. An increasing number of phylogeographical studies in the Arctic have laid a framework for testing hypotheses concerning the impact of shifting environmental conditions on transcontinental movement. We review 35 phylogeographical studies of trans-Beringian terrestrial and freshwater taxa, both hosts and parasites, to identify generalized patterns regarding the number, direction and timing of trans-continental colonizations. We found that colonization across Beringia was primarily from Asia to North America, with many events …

Grânulos De Amido E Fitólitos Em Cálculos Dentários Humanos: Contribuição Ao Estudo Do Modo De Vida E Subsistência De Grupos Sambaquianos Do Litoral Sul Do Brasil, Verônica Wesolowski, Sheila Maria Ferraz Mendonça De Souza, Karl Reinhard, Gregório Ceccantini

Karl Reinhard Publications

Este artigo tem por objetivo apresentar os resultados da recuperação e análise de micro-vestígios vegetais retidos em cálculos dentários de grupos de pescadores-coletores do litoral sul do Brasil. Apresenta também os resultados das relações mantidas entre grânulos de amido e cárie, e entre fitólitos e desgaste dentário.

Através da dissolução química de cálculos dentários foram recuperados microvestígios vegetais em todos os indivíduos estudados. Foi evidenciado o consumo de alimentos amiláceos em todas as séries esqueléticas estudadas, demonstrando independência entre dieta com aporte de produtos vegetais e utilização de cerâmica. Foram encontrados resultados sugestivos de padrões de escolha de alimentos diferenciados …

Mist Netting Bias, Species Accumulation Curves, And The Rediscovery Of Two Bats On Montserrat (Lesser Antilles), Roxanne Larsen, Karen A. Boegler, Hugh H. Genoways, Will P. Masefield, Ronan A. Kirsch, Scott C. Pedersen

University of Nebraska State Museum: Mammalogy Papers

Mist nets are commonly used to survey bat populations and to estimate bat biodiversity, but several studies have found that mist net capture data and methods are biased due to a number of factors, including size and placement of nets, and the frequency at which investigators check their nets. Despite the wealth of literature and anecdotal reports, few investigators have quantified the interactions of bats with mist nets directly. We employed night vision camcorders to monitor bat behavior when bats encountered a mist net and then utilized these data to reevaluate years of survey data collected on Montserrat, Lesser Antilles. …

Amazonian Exploitation Revisited: Ecological Asymmetry And The Policy Pendulum, Mark B. Bush, Miles R. Silman

Ocean Engineering and Marine Sciences Faculty Publications

The influence of pre-Columbian human populations on Amazonian ecosystems is being actively debated. The long-standing view that Amazonia was only minimally impacted by human actions has been challenged, and a new paradigm of Amazonia as a "manufactured landscape" is emerging. If such disturbance was the norm until just 500 years ago, Amazonian ecosystems could be far more ecologically resilient to disturbance than previously supposed. Alternatively, if the "manufactured landscape" label is an overstatement, then policy that assumes such resilience may cause substantial and long-lasting ecological damage. We present paleoecological data suggesting a middle path, in which some areas were heavily …

Pathways Of Anaerobic Carbon Cycling Across An Ombrotrophic–Minerotrophic Peatland Gradient, Jason K. Keller, Scott D. Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatland soils represent globally significant stores of carbon, and understanding carbon cycling pathways in these ecosystems has important implications for global climate change. We measured aceticlastic and autotrophic methanogenesis, sulfate reduction, denitrification, and iron reduction in a bog, an intermediate fen, and a rich fen in the Upper Peninsula of Michigan for one growing season. In 3-d anaerobic incubations of slurried peat, denitrification and iron reduction were minor components of anaerobic carbon mineralization. Experiments using 14C-labeled methanogenic substrates showed that methanogenesis in these peatlands was primarily through the aceticlastic pathway, except early in the growing season in more ombrotrophic peatlands, …

Chumming On The Chesapeake Bay And Complexity Theory: Why The Precautionary Principle, Not Cost-Benefit Analysis, Makes More Sense As A Regulatory Approach, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

Estuaries like the Chesapeake Bay ("Bay") and Puget Sound are in grave trouble. They each suffer from poor water quality, loss of habitat, and declining biodiversity, and efforts to restore their health are straining both public and private resources. While accomplishments are often recorded in the fight against these ills, it is clear these accomplishments "are not yet equal to the scale of the problems." The focus of this article is on the nation's largest estuary, the Bay. Despite the investment of billions of dollars to improve water quality, the Bay continues to suffer from severe environmental degradation that impairs …

Grotius, Ocean Fish Ranching, And The Public Trust Doctrine: Ride 'Em Charlie Tuna, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

Seventy percent of the world's fish populations are in serious decline; some have been fished to near extinction. While domestic and international efforts are underway to curb the rate at which the remaining fish are being depleted, the demand for fish appears to be outstripping these initiatives--before they can take hold, the fish may be gone. In response to this increasingly dire situation, many countries, including the United States, have turned to fish farming in hope of taking pressure off of certain wild stocks of fish while still meeting consumer demands for them. More recently, non-U.S. fish farmers have moved …

Administering The Clean Water Act: Do Regulators Have "Bigger Fish To Fry" When It Comes To Addressing The Practice Of Chumming On The Chesapeake Bay?, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

The Chesapeake Bay is one of the country's most productive estuaries. However, for decades the health of the Bay has been declining due in large part to nutrification. Excessive nutrients encourage algal blooms, which lower dissolved oxygen and increase turbidity in the Bay's waters. More than 40% of the Bay's main stern is now dead largely as a result of this problem. The practice of chumming, the discarding of baitfish, usually menhaden, over the sides of fishing boats to attract game fish like striped bass, is contributing to the Bay's nutrification problem because the decomposing chum raises the waters biological …

Plant Assemblage Structure On Barrier Island ‘Pimple’ Dunes At The Virginia Coast Reserve Long-Term Ecological Research Site, Brett A. Mcmillan

Biological Sciences Theses & Dissertations

The habitats at the VCR LTER that were the focus of the current study are the Hog Island and Parramore Island 'pimples', small, rounded dunes forming along main dune ridges of the barrier islands. There are distinct plant assemblage zones found on pimples, although most of these dunes are 10–20 m in diameter. Hypotheses of the study were that fresh water availability was a main determinant of differences between assemblages and that pimple size and location would influence diversity and assemblage structure. Research goals were (1) to describe the plant assemblages on pimples, (2) to relate edaphic and geomorphological factors …