Habitat Space Used by Northern Bobwhites and Texas Tortoises on South Texas Rangelands

South Texas rangelands are increasingly managed for recreational hunting, particularly northern bobwhite (Colinus virgianus). Effects of habitat management for game species on non-game species are largely unknown. Large private ranches used for recreational hunting could also provide habitat for the threatened Texas tortoise (Gopherus berlandieri). We studied habitat use of Texas tortoises and northern bobwhites on a private ranch in South Texas that undergoes active habitat management. In 2015, tortoises (n = 12) and bobwhite hens (n = 42) were tracked during their active and breeding seasons, respectively, with radio-telemetry. Satellite images were analyzed using ArcGIS 10.3 to delineate habitat through unsupervised classification for relevant habitat categories. Habitats were delineated based on reflectance. Differences in percent habitat composition of observed and random home ranges (100% Minimum Convex Polygon) of tortoises were not significant, but were significant for quail in 3 of 5 habitat categories in only 1 of 2 pastures. These observed quail home ranges included more areas corresponding to light woody cover and moderate herbaceous cover and fewer areas corresponding to sparsely vegetated or bare ground than random home ranges. Tortoise home ranges included more areas with woody brush cover than bobwhite home ranges. Bobwhite home ranges included more areas associated with moderate grass and herbaceous cover than tortoises. This study will continue in 2016 and will include more quail home ranges in areas with tortoises. This research seeks to determine the compatibility of managing for recreational hunting while maintaining landscape characteristics important to Texas tortoises

Survival of red knots in the northern Gulf of Mexico

Highly migratory shorebirds are among the fastest declining avian guilds, so determining causes of mortality is critically important for their conservation. Most of these species depend on a specific geographic arrangement of suitable sites that reliably provide resources needed to fuel physiologically demanding life histories. Long-term mark-resight projects allow researchers to investigate specific potential sources of variation in demographic rates between populations. Red Knots (Calidris canutus) occur in three relatively distinct regions across the northern Gulf of Mexico, and two of these areas have been experiencing episodic harmful algal blooms (red tide) with increased frequency in recent decades. Since knots are mostly molluscivorous during the nonbreeding season in the Gulf, they are potentially exposed to red tide toxins at high concentrations via their filter-feeding prey. We used long-term mark-resight data from Texas, Louisiana, and Florida (USA) to estimate apparent survival, and to assess the effects of red tides on survival of Red Knots. We also assessed effects of tracking devices deployed in conjunction with the projects over the years. While overall apparent annual survival rates were similar across the three locations (0.768 – 0.819), several red tide events were associated with catastrophically low seasonal (fall) survival in Florida (as low as 0.492) and Texas (as low as 0.510). Leg-mounted geolocators, but not temporary glued-on VHF tags, were associated with a reduction in apparent survival (~8%/year). Movement of knots between the three areas was rare and site fidelity is known to be high. Harmful algal blooms are predicted to increase in frequency and severity with climate change and increased anthropogenic degradation of coastal habitats, which may further endanger these as well as other shorebird populations around the world

Patterns of Ancestry, Signatures of Natural Selection, and Genetic Association with Stature in Western African Pygmies

African Pygmy groups show a distinctive pattern of phenotypic variation, including short stature, which is thought to reflect past adaptation to a tropical environment. Here, we analyze Illumina 1M SNP array data in three Western Pygmy populations from Cameroon and three neighboring Bantu-speaking agricultural populations with whom they have admixed. We infer genome-wide ancestry, scan for signals of positive selection, and perform targeted genetic association with measured height variation. We identify multiple regions throughout the genome that may have played a role in adaptive evolution, many of which contain loci with roles in growth hormone, insulin, and insulin-like growth factor signaling pathways, as well as immunity and neuroendocrine signaling involved in reproduction and metabolism. The most striking results are found on chromosome 3, which harbors a cluster of selection and association signals between approximately 45 and 60 Mb. This region also includes the positional candidate genes DOCK3, which is known to be associated with height variation in Europeans, and CISH, a negative regulator of cytokine signaling known to inhibit growth hormone-stimulated STAT5 signaling. Finally, pathway analysis for genes near the strongest signals of association with height indicates enrichment for loci involved in insulin and insulin-like growth factor signaling

DOMINO-AD protocol: donepezil and memantine in moderate to severe Alzheimer's disease - a multicentre RCT.

BACKGROUND: Alzheimer's disease (AD) is the commonest cause of dementia. Cholinesterase inhibitors, such as donepezil, are the drug class with the best evidence of efficacy, licensed for mild to moderate AD, while the glutamate antagonist memantine has been widely prescribed, often in the later stages of AD. Memantine is licensed for moderate to severe dementia in AD but is not recommended by the England and Wales National Institute for Health and Clinical Excellence. However, there is little evidence to guide clinicians as to what to prescribe as AD advances; in particular, what to do as the condition progresses from moderate to severe. Options include continuing cholinesterase inhibitors irrespective of decline, adding memantine to cholinesterase inhibitors, or prescribing memantine instead of cholinesterase inhibitors. The aim of this trial is to establish the most effective drug option for people with AD who are progressing from moderate to severe dementia despite treatment with donepezil. METHOD: DOMINO-AD is a pragmatic, 15 centre, double-blind, randomized, placebo controlled trial. Patients with AD, currently living at home, receiving donepezil 10 mg daily, and with Standardized Mini-Mental State Examination (SMMSE) scores between 5 and 13 are being recruited. Each is randomized to one of four treatment options: continuation of donepezil with memantine placebo added; switch to memantine with donepezil placebo added; donepezil and memantine together; or donepezil placebo with memantine placebo. 800 participants are being recruited and treatment continues for one year. Primary outcome measures are cognition (SMMSE) and activities of daily living (Bristol Activities of Daily Living Scale). Secondary outcomes are non-cognitive dementia symptoms (Neuropsychiatric Inventory), health related quality of life (EQ-5D and DEMQOL-proxy), carer burden (General Health Questionnaire-12), cost effectiveness (using Client Service Receipt Inventory) and institutionalization. These outcomes are assessed at baseline, 6, 18, 30 and 52 weeks. All participants will be subsequently followed for 3 years by telephone interview to record institutionalization. DISCUSSION: There is considerable debate about the clinical and cost effectiveness of anti-dementia drugs. DOMINO-AD seeks to provide clear evidence on the best treatment strategies for those managing patients at a particularly important clinical transition point. TRIAL REGISTRATION: Current controlled trials ISRCTN49545035.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Habitat Associations of Migrating and Overwintering Grassland Birds in Southern Texas

We report on the habitat associations of 21 species of grassland birds over- wintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of the total bird densities in grassland and shrub-grassland habitats, but much lower proportions in the habitats with more woody vegetation. Fewer grassland species were observed in grassland and woodland than in brushland, parkland, and shrub-grassland habitats. Grassland birds generally were found in higher densities in habitats that had woody canopy coverage of \u3c 30%; densities of grassland birds were highest in shrub-grassland habitat and lowest in woodland habitat. Species that are grassland specialists on their breeding grounds tended to be more habitat specific during the nonbreeding season compared to shrub-grassland specialists, which were more general in their nonbreeding-habitat usage. Nonetheless, our data demonstrate that grassland birds occur in a variety of habitats during the nonbreeding season and seem to occupy a broader range of habitats than previously described

Habitat Associations of Migrating and Overwintering Grassland Birds in Southern Texas

We report on the habitat associations of 21 species of grassland birds over- wintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of the total bird densities in grassland and shrub-grassland habitats, but much lower proportions in the habitats with more woody vegetation. Fewer grassland species were observed in grassland and woodland than in brushland, parkland, and shrub-grassland habitats. Grassland birds generally were found in higher densities in habitats that had woody canopy coverage of \u3c 30%; densities of grassland birds were highest in shrub-grassland habitat and lowest in woodland habitat. Species that are grassland specialists on their breeding grounds tended to be more habitat specific during the nonbreeding season compared to shrub-grassland specialists, which were more general in their nonbreeding-habitat usage. Nonetheless, our data demonstrate that grassland birds occur in a variety of habitats during the nonbreeding season and seem to occupy a broader range of habitats than previously described

Nutritional ecology of northern pintails wintering in the Laguna Madre of Texas

Major subject: Wildlife science.Molt intensity, digestive tract morphology, diet, and carcass composition of northern pintails were investigated along the southern Texas Coast during winters of 1997-98 and 1998-99. Precipitation was 133% and 83% of the long-term average during 1997-98 and 1998-99, respectively. Prealternate molt was less intense during winter of the wet year compared to the dry year and may have been initiated earlier. Pintail diets were dominated by plant material during most seasons. Foods consumed by pintails in the Laguna Madre were low in fat, protein, and true metabolizable energy relative to foods consumed by pintails in freshwater habitats. Gammarus was the most digestible food consumed and provided the greatest energy/g of dry mass. The overall diet of pintails during winter provided from 0.44 to 1.38 kcal/g of TMEN and was notably of lower quality during the dry year compared to the wet year. The diet of pintails wintering along the southern Texas Coast appears to provide considerably less energy than diets of pintails wintering in freshwater habitats. Most reductions in mass of digestive tract occurred from early December through February and appeared to result from catabolism of lean tissue and not from changes in diet quality. Lipid reserves were catabolized throughout winter both years, however, a simultaneous decline in lean body mass during the wet year resulted in percent fat remaining constant. In the dry year, fat was reduced (P 63% between October and the end of February. Somatic protein significantly declined throughout winter both years (P < 0.001) and pintails departed the Laguna Madre approximately 200 g lighter than has been reported for pintails departing rice habitats in California. Continued reductions in freshwater and rice habitats along the Texas Coast may negatively impact pintail populations in Texas if pintails shift their winter distribution to saline, coastal habitats that appear to provide poorer quality diets and result in birds departing wintering grounds in impoverished body condition. However, pintails wintering in freshwater habitats in western Texas were reported to exhibit similar patterns in nutrient reserves to pintails wintering in the Laguna Madre which may indicate an adaptive strategy during winter

Nutritional ecology of northern pintails wintering in the Laguna Madre of Texas

Major subject: Wildlife science.Molt intensity, digestive tract morphology, diet, and carcass composition of northern pintails were investigated along the southern Texas Coast during winters of 1997-98 and 1998-99. Precipitation was 133% and 83% of the long-term average during 1997-98 and 1998-99, respectively. Prealternate molt was less intense during winter of the wet year compared to the dry year and may have been initiated earlier. Pintail diets were dominated by plant material during most seasons. Foods consumed by pintails in the Laguna Madre were low in fat, protein, and true metabolizable energy relative to foods consumed by pintails in freshwater habitats. Gammarus was the most digestible food consumed and provided the greatest energy/g of dry mass. The overall diet of pintails during winter provided from 0.44 to 1.38 kcal/g of TMEN and was notably of lower quality during the dry year compared to the wet year. The diet of pintails wintering along the southern Texas Coast appears to provide considerably less energy than diets of pintails wintering in freshwater habitats. Most reductions in mass of digestive tract occurred from early December through February and appeared to result from catabolism of lean tissue and not from changes in diet quality. Lipid reserves were catabolized throughout winter both years, however, a simultaneous decline in lean body mass during the wet year resulted in percent fat remaining constant. In the dry year, fat was reduced (P 63% between October and the end of February. Somatic protein significantly declined throughout winter both years (P < 0.001) and pintails departed the Laguna Madre approximately 200 g lighter than has been reported for pintails departing rice habitats in California. Continued reductions in freshwater and rice habitats along the Texas Coast may negatively impact pintail populations in Texas if pintails shift their winter distribution to saline, coastal habitats that appear to provide poorer quality diets and result in birds departing wintering grounds in impoverished body condition. However, pintails wintering in freshwater habitats in western Texas were reported to exhibit similar patterns in nutrient reserves to pintails wintering in the Laguna Madre which may indicate an adaptive strategy during winter