New Applications of Radio Frequency Identification Stations for Monitoring Fish Passage through Headwater Road Crossings and Natural Reaches

Within the Ouachita National Forest, roads and streams intersect each other thousands of times. Many of these road crossings alter stream hydrology and potentially limit longitudinal fish movement. To investigate the potential impacts of these road crossings on fish passage, we monitored movements of 3 native fish species (n = 2,171) individually tagged with radio frequency identification (RFID) tags in 2012 and 2013. We installed solar-powered RFID stations in 2 streams with road crossings and 2 reference streams without road crossings. Each of the 4 monitoring stations included a pair of antennas bracketing a road crossing (or similarly-sized natural reach) to continuously detect upstream or downstream passage. To monitor natural reference streams, we avoided full-duplex RFID technology, which would have required rigid in-stream structures. Alternatively, we utilized new applications of RFID technology such as direct in-stream installation of half-duplex wire antennas and figure-eight crossover antenna designs. These techniques appear promising, but technical difficulties limited the consistency of fish passage detection and consequently limited the strength of ecological conclusions. Even so, we report evidence that fish passed at significantly higher rates across reference reaches than reaches with road crossings. Furthermore, Creek Chub (Semotilus atromaculatus) passed reference reaches at significantly higher rates than Highland Stonerollers (Campostoma spadiceum), which passed at higher rates than Longear Sunfish (Lepomis megalotis). Stream intermittency appeared to exacerbate reduced passage rates associated with the road crossings

Effects of Zebra, Mussel, Dreissena Polymorpha Infestation on Lake Dardanelle Water Quality

Zebra mussels recently invaded southern waterways including the Arkansas River. Large-scale filtration of suspended particulate matter by dense populations could alter reservoir ecosystem function. Furthermore, they attach to hard surfaces, thereby threatening normal operations of artificial structures. We designed this study to provide baseline data prior to establishment of high population levels of zebra mussels in Lake Dardanelle. The characterization of spatial and temporal variability in water quality, zooplankton, phytoplankton, and macrophytes will allow testing of several hypotheses. We sampled zebra mussel veliger and settling juvenile densities and zooplankton densities at four fixed sites and the key water quality variables at three of the sites biweekly from July 1995 through June 1996. Data from previous years regarding the above parameters is contained in other reports. Production of zebra mussel veligers was approximately the same between the 1994-1995 and 1995-1996 sample seasons, but the number of adults increased dramatically. Veliger density frequently exceeded 20/L and the mean density of adults was \u3e 4,000 m2 during the 1995-1996 sample season. We observed substantial increases in ion concentrations, phosphate, conductivity, and Secchi disk visibility this sample season compared to the 1994-1995 sample season. Mean concentrations for calcium, magnesium, sulfate, chloride, and phosphate increased 43%, 42%, 42%, 48%, and 50%, respectively. Mean conductivity increased 44%, and four of the five highest Secchi disk readings taken the past three years were recorded in 1996. We observed substantial decreases in turbidity (31%), total dissolved solids (23%), and total phosphorous (13%). Densities of major zooplankton taxa were not substantially different this season compared with the 1994-1995 sample season. We observed slight increases in mean concentrations of chlorophylls a, b, and c, and a slight decrease in the mean percent coverage of rooted marcrophytes, but the values were not substantially different than those that we observed during the 1994-1995 sample season

Quantification and Prediction of Stream Dryness in the Interior Highlands

Although ecological studies have noted streams drying in the Interior Highlands, published measurements of streambed dryness are lacking. Clearly, stream drying has the potential to affect benthic macroinvertebrate and fish communities. In 2003, we initiated an assessment of streambed dryness for three streams in the Ouachita Mountains representative of the Central Hills, Ridges, and Valleys. In the following summer, we applied the approach to 15 similar size watersheds in three distinct ecoregions of the Interior Highlands: Ouachita Mountains-Athens Plateau, Ozark Highlands-Springfield Plateau, and Lower Boston Mountains. Repeated dryness measurements were recorded in each stream and correlated to nearby USGS stream gage records. Dryness reached as high as 86% for the Ouachita Mountains in 2003; whereas, flow was continuous in 2004. One stream in the Ozark Highlands dried completely in 2004, and dryness reached 84% in the Boston Mountains. Percent dry streambed was negatively correlated (Spearman rank) to discharge for the Ouachita Mountains in 2003 and the Boston Mountains in2004 (rs =-0.94 and -0.60, respectively; p \u3c 0.05, Ukey-Kramer). Maximum dryness during these months was significantly lower for the Ouachita Mountains than the Boston mountains and Ozark Highlands. Thus, discernable patterns of stream dryness exist among the different ecoregions of the Interior Highlands. Aquatic ecologists and resource managers in these ecoregions could employ such measures to further understand habitat limitations associated with these stream systems

Better Outcomes for Older people with Spinal Trouble (BOOST) Trial: a randomised controlled trial of a combined physical and psychological intervention for older adults with neurogenic claudication, a protocol

Introduction Neurogenic claudication due to spinal stenosis is common in older adults. The effectiveness of conservative interventions is not known. The aim of the study is to estimate the clinical and cost-effectiveness of a physiotherapist-delivered, combined physical and psychological intervention. Methods and analysis This is a pragmatic, multicentred, randomised controlled trial. Participants are randomised to a combined physical and psychological intervention (Better Outcomes for Older people with Spinal Trouble (BOOST) programme) or best practice advice (control). Community-dwelling adults, 65 years and over, with neurogenic claudication are identified from community and secondary care services. Recruitment is supplemented using a primary care-based cohort. Participants are registered prospectively and randomised in a 2:1 ratio (intervention:control) using a web-based service to ensure allocation concealment. The target sample size is a minimum of 402. The BOOST programme consists of an individual assessment and twelve 90 min classes, including education and discussion underpinned by cognitive behavioural techniques, exercises and walking circuit. During and after the classes, participants undertake home exercises and there are two support telephone calls to promote adherence with the exercises. Best practice advice is delivered in one to three individual sessions with a physiotherapist. The primary outcome is the Oswestry Disability Index at 12 months. Secondary outcomes include the 6 Minute Walk Test, Short Physical Performance Battery, Fear Avoidance Beliefs Questionnaire and Gait Self-Efficacy Scale. Outcomes are measured at 6 and 12 months by researchers who are masked to treatment allocation. The primary statistical analysis will be by ‘intention to treat’. There is a parallel health economic evaluation and qualitative study

Extensive microbial and functional diversity within the chicken cecal microbiome

Chickens are major source of food and protein worldwide. Feed conversion and the health of chickens relies on the largely unexplored complex microbial community that inhabits the chicken gut, including the ceca. We have carried out deep microbial community profiling of the microbiota in twenty cecal samples via 16S rRNA gene sequences and an in-depth metagenomics analysis of a single cecal microbiota. We recovered 699 phylotypes, over half of which appear to represent previously unknown species. We obtained 648,251 environmental gene tags (EGTs), the majority of which represent new species. These were binned into over two-dozen draft genomes, which included Campylobacter jejuni and Helicobacter pullorum. We found numerous polysaccharide- and oligosaccharide-degrading enzymes encoding within the metagenome, some of which appeared to be part of polysaccharide utilization systems with genetic evidence for the co-ordination of polysaccharide degradation with sugar transport and utilization. The cecal metagenome encodes several fermentation pathways leading to the production of short-chain fatty acids, including some with novel features. We found a dozen uptake hydrogenases encoded in the metagenome and speculate that these provide major hydrogen sinks within this microbial community and might explain the high abundance of several genera within this microbiome, including Campylobacter, Helicobacter and Megamonas

Tree-ring isotopes suggest atmospheric drying limits temperature–growth responses of treeline bristlecone pine

Altitudinally separated bristlecone pine populations in the White Mountains (California, USA) exhibit differential climate-growth responses as temperature and tree-water relations change with altitude. These populations provide a natural experiment to explore the ecophysiological adaptations of this unique tree species to the twentieth century climate variability. We developed absolutely dated annual ring-width chronologies, and cellulose stable carbon and oxygen isotope chronologies from bristlecone pine growing at the treeline (~3500 m) and ~200 m below for the period AD 1710-2010. These chronologies were interpreted in terms of ecophysiological adaptations to climate variability with a dual-isotope model and a leaf gas exchange model. Ring widths show positive tree growth anomalies at treeline and consistent slower growth below treeline in relation to the twentieth century warming and associated atmospheric drying until the 1980s. Growth rates of both populations declined during and after the 1980s when growing-season temperature and atmospheric vapour pressure deficit continued to increase. Our model-based interpretations of the cellulose stable isotopes indicate that positive treeline growth anomalies prior to the 1980s were related to increased stomatal conductance and leaf-level transpiration and photosynthesis. Reduced growth since the 1980s occurred with a shift to more conservative leaf gas exchange in both the treeline and below-treeline populations, whereas leaf-level photosynthesis continued to increase in response to rising atmospheric CO2 concentrations. Our results suggest that warming-induced atmospheric drying confounds positive growth responses of apparent temperature-limited bristlecone pine populations at treeline. In addition, the observed ecophysiological responses of attitudinally separated bristlecone pine populations illustrate the sensitivity of conifers to climate change

New Applications of Radio Frequency Identification Stations for Monitoring Fish Passage through Headwater Road Crossings and Natural Reaches

Within the Ouachita National Forest, roads and streams intersect each other thousands of times. Many of these road crossings alter stream hydrology and potentially limit longitudinal fish movement. To investigate the potential impacts of these road crossings on fish passage, we monitored movements of 3 native fish species (n = 2,171) individually tagged with radio frequency identification (RFID) tags in 2012 and 2013. We installed solar-powered RFID stations in 2 streams with road crossings and 2 reference streams without road crossings. Each of the 4 monitoring stations included a pair of antennas bracketing a road crossing (or similarly-sized natural reach) to continuously detect upstream or downstream passage. To monitor natural reference streams, we avoided full-duplex RFID technology, which would have required rigid in-stream structures. Alternatively, we utilized new applications of RFID technology such as direct in-stream installation of half-duplex wire antennas and figure-eight crossover antenna designs. These techniques appear promising, but technical difficulties limited the consistency of fish passage detection and consequently limited the strength of ecological conclusions. Even so, we report evidence that fish passed at significantly higher rates across reference reaches than reaches with road crossings. Furthermore, Creek Chub (Semotilus atromaculatus) passed reference reaches at significantly higher rates than Highland Stonerollers (Campostoma spadiceum), which passed at higher rates than Longear Sunfish (Lepomis megalotis). Stream intermittency appeared to exacerbate reduced passage rates associated with the road crossings

Quantification and Prediction of Stream Dryness in the Interior Highlands

Although ecological studies have noted streams drying in the Interior Highlands, published measurements of streambed dryness are lacking. Clearly, stream drying has the potential to affect benthic macroinvertebrate and fish communities. In 2003, we initiated an assessment of streambed dryness for three streams in the Ouachita Mountains representative of the Central Hills, Ridges, and Valleys. In the following summer, we applied the approach to 15 similar size watersheds in three distinct ecoregions of the Interior Highlands: Ouachita Mountains-Athens Plateau, Ozark Highlands-Springfield Plateau, and Lower Boston Mountains. Repeated dryness measurements were recorded in each stream and correlated to nearby USGS stream gage records. Dryness reached as high as 86% for the Ouachita Mountains in 2003; whereas, flow was continuous in 2004. One stream in the Ozark Highlands dried completely in 2004, and dryness reached 84% in the Boston Mountains. Percent dry streambed was negatively correlated (Spearman rank) to discharge for the Ouachita Mountains in 2003 and in the Boston Mountains in 2004 (rs = -0.94 and -0.60, respectively; p ≤ 0.01). Lowest monthly mean daily discharge, corrected for watershed area, differed among ecoregions for May through October in 2004 (highest discharge in the Ouachita Mountains, p ≤ 0.05, Tukey-Kramer). Maximum dryness during these months was significantly lower for the Ouachita Mountains than the Boston Mountains and Ozark Highlands. Thus, discernable patterns of stream dryness exist among the different ecoregions of the Interior Highlands. Aquatic ecologists and resource managers in these ecoregions could employ such measures to further understand habitat limitations associated with these stream systems