Revisions of Rump Fat and Body Scoring Indices for Deer,Elk, and Moose

Abstract: Because they do not require sacrificing animals, body condition scores (BCS), thickness of rump fat (MAXFAT), and other similar predictors of body fat have advanced estimating nutritional condition of ungulates and their use has proliferated in North America in the last decade. However, initial testing of these predictors was too limited to assess their reliability among diverse habitats, ecotypes, subspecies, and populations across the continent. With data collected from mule deer (Odocoileus hemionus), elk (Cervus elaphus), and moose (Alces alces) during initial model development and data collected subsequently from free-ranging mule deer and elk herds across much of the western United States, we evaluated reliability across a broader range of conditions than were initially available. First, to more rigorously test reliability of the MAXFAT index, we evaluated its robustness across the 3 species, using an allometric scaling function to adjust for differences in animal size. We then evaluated MAXFAT, rump body condition score (rBCS), rLIVINDEX (an arithmetic combination of MAXFAT and rBCS), and our new allometrically scaled rump-fat thickness index using data from 815 free-ranging female Roosevelt and Rocky Mountain elk (C. e. roosevelti and C. e. nelsoni) from 19 populations encompassing 4 geographic regions and 250 free-ranging female mule deer from 7 populations and 2 regions. We tested for effects of subspecies, geographic region, and captive versus free-ranging existence. Rump-fat thickness, when scaled allometrically with body mass, was related to ingesta-free body fat over a 38–522-kg range of body mass (r² = 0.87; P < 0.001), indicating the technique is remarkably robust among at least the 3 cervid species of our analysis. However, we found an underscoring bias with the rBCS for elk that had >12% body fat. This bias translated into a difference between subspecies, because Rocky Mountain elk tended to be fatter than Roosevelt elk in our sample. Effects of observer error with the rBCS also existed for mule deer with moderate to high levels of body fat, and deer body size significantly affected accuracy of the MAXFAT predictor. Our analyses confirm robustness of the rump-fat index for these 3 species but highlight the potential for bias due to differences in body size and to observer error with BCS scoring. We present alternative LIVINDEX equations where potential bias from rBCS and bias due to body size are eliminated or reduced. These modifications improve the accuracy of estimating body fat for projects intended to monitor nutritional status of herds or to evaluate nutrition's influence on population demographics.     

The Occurrence and Survival of Coliforms and Salmonellas in Apple Juice and Cider

Apples and juices from large and small cidermakers were examined for the presence of coliform organisms and salmonellas. Coliforms were found both on the fruit and in the juice, and salmonellas were isolated on more than one occasion from the flume water. Experiments showed that salmonellas could survive in apple juice for 30 d at a pH of 3·6.     

Long‐distance geneflow and habitat specificity of the rock‐dwelling coppertail skink,Ctenotus taeniolatus

Rock boulders or ‘bush‐rocks’ provide essential habitat for many organisms and there has been interest in rehabilitating areas denuded of rock with artificial substitutes. We examine whether the density and size of bush rock influences the density of the coppertail skink (Ctenotus taeniolatus). The success of habitat rehabilitation is contingent on dispersal of rock‐dwelling organisms into areas that have been remediated. To gauge the likelihood of this we characterize geneflow of coppertail skinks among discrete patches of rocky habitat associated with ridge tops. We genotyped 154 individuals from seven localities at six microsatellite DNA loci and from a subset of these individuals we obtained sequence data from the mitochondrial ND4 region. Our field survey established that lizard density was positively associated with the availability of suitably sized bush‐rock (P < 0.001), highlighting the importance of maintaining this habitat element, or replacing it where it has been lost. Despite the presence of habitat features that might be presumed as barriers to dispersal for coppertail skinks, such as intervening gullies and dense vegetation, our genetic data demonstrated high levels of geneflow among rocky ridge tops. Levels of partitioning estimated by global F_ST were significant but low for both microsatellite (F_ST = 0.020) and mitochondrial data (F_ST = 0.113). Spatial autocorrelation of genotypic similarity supports our conclusion of regular longer‐distance geneflow, and we infer lower levels of dispersal in juveniles than in adults. This study suggests that dispersal of coppertail skinks can be sufficient to naturally colonize areas of restored habitat.     

Trophic interactions and benthic animal community structure in the Colorado River, Arizona, U.S.A.

1. Cladophora glomerata is the dominant filamentous green alga in the tailwaters of the Colorado River, U.S.A., below Glen Canyon Dam, but becomes co-dominant with filamentous cyanobacteria, Oscillatoria spp., below the confluence of the Paria River (26km below the dam) where suspended sediments are elevated. 2. Benthic algal assemblages played an important role in the distribution of the amphipod, Gammarus lacustris, in the dam-controlled Colorado River through Grand Canyon National Park, Arizona. Cladophara and G. lacustris showed a weak positive relationship at ten cobble-riffle habitats in the Colorado River from Lees Ferry (25km below the dam) to Diamond Creek (362km downstream), while no relationship was found between Oscillatoria and G. lacustris. 3. The relationship between algal substrata and G. lacustris was tested by a series of in situ habitat choice experiments. G. lacustris showed a significant preference for Cladophora (with epiphytes) over Oscillatoria spp., detritus and gravel in treatment pans at Lees Ferry. 4. Epiphytic diatoms (i.e. food) were the overriding determinant of subtratum choice by G. lacustris in laboratory experiments. Gammarus chose the Cladophora/epiphytic diatom community over sonicated Cladophora with few diatoms. The amphipods also chose string soaked in diatom extract over string without diatom extract. 5. Importance of mutualistic interactions in aquatic benthic community structure is discussed.     

Elevated CO2 and tree fecundity: the role of tree size, interannual variability, and population heterogeneity

Long‐term population effects of changes in atmospheric CO₂ will be largely determined by reproductive effort. Our research objectives were to quantify variability in seed production and rate of maturation among individual Pinus taeda L. (Pinaceae) trees growing in elevated CO₂ (ambient plus 200 μL L^?1) since 1996. Estimating tree fecundity in nature is frustrated by the difficulty of counting seeds from individual trees and the need for long‐term data. We have used a hierarchical Bayes approach to model individual tree fecundity, accounting for the complexity of experimentation in a natural setting over multiple years. The study presented here demonstrates large variability in natural fecundity rates and contributes to our understanding of how both interannual variation and population heterogeneity influence elevated CO₂ effects. We found that trees growing under elevated CO₂ matured earlier and produced more seeds and cones per unit basal area than ambient grown trees. By 2004, trees grown in high CO₂ had produced an average 300 more seeds per tree than ambient grown trees. Although there was a trend toward decreasing mean CO₂ effect (difference in fecundity between elevated and ambient treatments) over time, the hierarchical analysis indicates that this decrease comes from the emergence of a few highly fecund ambient grown trees by 2002, rather than acclimation or downregulation among the fumigated trees. The most important effect of increased CO₂ in forest ecosystems may be the increase in fecundity reported here. Although biomass responses can sometimes be large, the increase in fecundity can have long‐term impacts on forest dynamics that transcend the current generation.     

Greater seed production in elevated CO2 is not accompanied by reduced seed quality in Pinus taeda L.

For herbaceous species, elevated CO₂ often increases seed production but usually leads to decreased seed quality. However, the effects of increased atmospheric CO₂ on tree fecundity remain uncertain, despite the importance of reproduction to the composition of future forests. We determined how seed quantity and quality differed for pine trees grown for 12 years in ambient and elevated (ambient+200 μL L^?1) CO₂, at the Duke Forest free‐air CO₂ enrichment (FACE) site. We also compared annual reproductive effort with yearly measurements of aboveground net primary productivity (ANPP), precipitation (P), potential evapotranspiration (PET) and water availability [precipitation minus potential evapotranspiration (P?PET)] to investigate factors that may drive interannual variation in seed production. The number of mature, viable seeds doubled per unit basal area in high‐CO₂ plots from 1997 to 2008 (P<0.001), but there was no CO₂ effect on mean seed mass, viability, or nutrient content. Interannual variation in seed production was positively related to ANPP, with a similar percentage of ANPP diverted to reproduction across years. Seed production was negatively related to PET (P<0.005) and positively correlated with water availability (P<0.05), but showed no relationship with precipitation (P=0.88). This study adds to the few findings that, unlike herbaceous crops, woody plants may benefit from future atmospheric CO₂ by producing larger numbers of seeds without suffering degraded seed quality. Differential reproductive responses between functional groups and species could facilitate woody invasions or lead to changes in forest community composition as CO₂ rises.     

At the Crossroads of Human Rights and Anthropology: Toward a Critically Engaged Activist Research

In this article, I consider anthropology's engagement with human rights today. Through the lens of my experience in a case brought before the International Labor Organization by a community in Chiapas, Mexico, I consider the ethical, practical, and epistemological questions that arise in research defined by rights activism. I argue that the critical engagement brought about by activist research is both necessary and productive. Such research can contribute to transforming the discipline by addressing the politics of knowledge production and working to decolonize our research process. Rather than seeking to avoid or resolve the tensions inherent in anthropological research on human rights, activist research draws them to the fore, making them a productive part of the process. Finally, activist research allows us to merge cultural critique with political action to produce knowledge that is empirically grounded, theoretically valuable, and ethically viable.