Feasibility of non-lethal approaches to protect riparian plants from foraging beavers in North America

Beavers in North America will occupy almost any wetland area containing available forage. Wetland restoration projects often provide the resources necessary for dispersing beavers to create desirable habitats. Their wide distribution and ability to disperse considerable distances almost assure that beavers will establish themselves in new wetlands. Although beavers are a natural and desirable component of a wetland ecosystem, their foraging behaviors can be destructive. Fencing may be a feasible approach to reduce damage to small, targeted areas, and textural repellents may provide some utility to protect established trees. However, these non-lethal approaches will be marginally effective when beaver populations become excessive. Beaver populations need to be maintained at levels that permit viable colonies while still permitting plant communities to flourish. This will require a better understanding of beaver movements, site and forage selection, and reproductive characteristics. This is particularly true when management objectives and regulations prohibit beaver removal from project sites

Spatial Processes Decouple Management from Objectives in a Heterogeneous Landscape: Predator Control as a Case Study

Predator control is often implemented with the intent of disrupting top‐down regulation in sensitive prey populations. However, ambiguity surrounding the efficacy of predator management, as well as the strength of top‐down effects of predators in general, is often exacerbated by the spatially implicit analytical approaches used in assessing data with explicit spatial structure. Here, we highlight the importance of considering spatial context in the case of a predator control study in south‐central Utah. We assessed the spatial match between aerial removal risk in coyotes (Canis latrans) and mule deer (Odocoileus hemionus) resource selection during parturition using a spatially explicit, multi‐level Bayesian model. With our model, we were able to evaluate spatial congruence between management action (i.e., coyote removal) and objective (i.e., parturient deer site selection) at two distinct scales: the level of the management unit and the individual coyote removal. In the case of the former, our results indicated substantial spatial heterogeneity in expected congruence between removal risk and parturient deer site selection across large areas, and is a reflection of logistical constraints acting on the management strategy and differences in space use between the two species. At the level of the individual removal, we demonstrated that the potential management benefits of a removed coyote were highly variable across all individuals removed and in many cases, spatially distinct from parturient deer resource selection. Our methods and results provide a means of evaluating where we might anticipate an impact of predator control, while emphasizing the need to weight individual removals based on spatial proximity to management objectives in any assessment of large‐scale predator control. Although we highlight the importance of spatial context in assessments of predator control strategy, we believe our methods are readily generalizable in any management or large‐scale experimental framework where spatial context is likely an important driver of outcomes

GMOs in animal agriculture: time to consider both costs and benefits in regulatory evaluations

In 2012, genetically engineered (GE) crops were grown by 17.3 million farmers on over 170 million hectares. Over 70% of harvested GE biomass is fed to food producing animals, making them the major consumers of GE crops for the past 15 plus years. Prior to commercialization, GE crops go through an extensive regulatory evaluation. Over one hundred regulatory submissions have shown compositional equivalence, and comparable levels of safety, between GE crops and their conventional counterparts. One component of regulatory compliance is whole GE food/feed animal feeding studies. Both regulatory studies and independent peer-reviewed studies have shown that GE crops can be safely used in animal feed, and rDNA fragments have never been detected in products (e.g. milk, meat, eggs) derived from animals that consumed GE feed. Despite the fact that the scientific weight of evidence from these hundreds of studies have not revealed unique risks associated with GE feed, some groups are calling for more animal feeding studies, including long-term rodent studies and studies in target livestock species for the approval of GE crops. It is an opportune time to review the results of such studies as have been done to date to evaluate the value of the additional information obtained. Requiring long-term and target animal feeding studies would sharply increase regulatory compliance costs and prolong the regulatory process associated with the commercialization of GE crops. Such costs may impede the development of feed crops with enhanced nutritional characteristics and durability, particularly in the local varieties in small and poor developing countries. More generally it is time for regulatory evaluations to more explicitly consider both the reasonable and unique risks and benefits associated with the use of both GE plants and animals in agricultural systems, and weigh them against those associated with existing systems, and those of regulatory inaction. This would represent a shift away from a GE evaluation process that currently focuses only on risk assessment and identifying ever diminishing marginal hazards, to a regulatory approach that more objectively evaluates and communicates the likely impact of approving a new GE plant or animal on agricultural production systems

Mountain beaver home ranges, habitat use, and population dynamics in Washington

The mountain beaver (Aplodontia rufa (Rafinesque, 1817)), endemic to western North America, is the only extant member of the family Aplodontidae. Limited information on movements and habitat use throughout the species\u27 range is available. We radio-collared 41 mountain beavers to determine home ranges, dispersal, habitat use, and population densities on two managed forest sites in coastal Washington. Both sites were recently harvested for timber. The Donovan site (16.6 ha) was treated with herbicide before seedling planting and the Sylvia site (8.9 ha) was not treated. Mountain beaver home ranges (Donovan: 4.18 ± 0.81 ha; Sylvia: 1.39 ± 0.4 ha) were greater than previously reported in the literature (0.02-0.2 ha). Home ranges (P = 0.009) and core use areas (P = 0.05) on the herbicide-treated Donovan site were larger than those observed on the untreated Sylvia site. Mountain beaver population density declined from 2002 (n = 16) to 2003 (n = 8) on the Donovan site, and reinvasion onto the site after removal trapping was low (n = 7). Population density more than doubled on the Sylvia site from 2002 (n = 21) to 2003 (n = 55), and reinvasion was greater (n = 27) than observed at Donovan. In addition, we documented habitat characteristics centered at 9 Donovan and 10 Sylvia nest locations. Sites were similar in most habitat characteristics, but the Sylvia site had more herbaceous forbs, stumps, and woody debris. Our findings suggest that mountain beaver populations and home ranges are affected by availability of forage, such as herbaceous forbs, after herbicide treatment, as well as by availability of woody cover

A Novel Ultrasound Technique for Detection of Osteochondral Defects in the Ankle Joint: A Parametric and Feasibility Study

(Osteo)chondral defects (OCDs) in the ankle are currently diagnosed with modalities that are not convenient to use in long-term follow-ups. Ultrasound (US) imaging, which is a cost-effective and non-invasive alternative, has limited ability to discriminate OCDs. We aim to develop a new diagnostic technique based on US wave propagation through the ankle joint. The presence of OCDs is identified when a US signal deviates from a reference signal associated with the healthy joint. The feasibility of the proposed technique is studied using experimentally-validated 2D finite-difference time-domain models of the ankle joint. The normalized maximum cross correlation of experiments and simulation was 0.97. Effects of variables relevant to the ankle joint, US transducers and OCDs were evaluated. Variations in joint space width and transducer orientation made noticeable alterations to the reference signal: normalized root mean square error ranged from 6.29% to 65.25% and from 19.59% to 8064.2%, respectively. The results suggest that the new technique could be used for detection of OCDs, if the effects of other parameters (i.e., parameters related to the ankle joint and US transducers) can be reduced

Update Estimasi Emisi Gas Buang Kapal di Perairan Batam-Singapore Menggunakan Data Automatic Identification System (Ais)

Penelitian ini bertujuan untuk menghitung emisi gas buang yang dihasilkan dari aktifitas pelayaran kapal yang berada di perairan Batam-Singapore menggunakan data AIS (Automatic Identification System). Wilayah ini merupakan salah satu wilayah perairan dengan aktifitas pelayaran terpadat sepanjang selat Malaka. Hasil analisa menunjukkan jumlah rata-rata kapal per-jam pada 4 September 2018 sebanyak 1191 kapal dengan kepadatan tertinggi terjadi pada pukul 22.00 dengan jumlah 1326 kapal. Hasil perhitungan emisi pada jam tersebut menunjukkan jumlah emisi NOx, CO, CO2, VOC, SOx and PM masing-masing sebesar 48,716.48 kg/hour, 62,297.39 kg/hour, 3,541,656.53 kg/hour, 14,751.79 kg/hour, 1,339.14 kg/hour and 22,319.03 kg/hour. Hasil ini merupakan updating nilai emisi dari penelitian-penelitian sebelumnya yang menggunakan data AIS perjam pada tahun 2011 dan 2014. Hasil perbandingan menunjukkan perbedaan cukup signifikan terhadap nilai emisi CO

The Two-Way Nested Global Chemistry-Transport Zoom Model TM5. Algorithm and Applications

Abstract not availableJRC.H-Institute for environment and sustainability (Ispra