Empirical analysis and modeling of Argos Doppler location errors in Romania

Background Advances in wildlife tracking technology have allowed researchers to understand the spatial ecology of many terrestrial and aquatic animal species. Argos Doppler is a technology that is widely used for wildlife tracking owing to the small size and low weight of the Argos transmitters. This allows them to be fitted to small-bodied species. The longer lifespan of the Argos units in comparison to units outfitted with miniaturized global positioning system (GPS) technology has also recommended their use. In practice, large Argos location errors often occur due to communication conditions such as transmitter settings, local environment, and the behavior of the tracked individual. Methods Considering the geographic specificity of errors and the lack of benchmark studies in Eastern Europe, the research objectives were: (1) to evaluate the accuracy of Argos Doppler technology under various environmental conditions in Romania, (2) to investigate the effectiveness of straightforward destructive filters for improving Argos Doppler data quality, and (3) to provide guidelines for processing Argos Doppler wildlife monitoring data. The errors associated with Argos locations in four geographic locations in Romania were assessed during static, low-speed and high-speed tests. The effectiveness of the Douglas Argos distance angle filter algorithm was then evaluated to ascertain its effect on the minimization of localization errors. Results Argos locations received in the tests had larger associated horizontal errors than those indicated by the operator of the Argos system, including under ideal reception conditions. Positional errors were similar to those obtained in other studies outside of Europe. The errors were anisotropic, with larger longitudinal errors for the vast majority of the data. Errors were mostly related to speed of the Argos transmitter at the time of reception, but other factors such as topographical conditions and orientation of antenna at the time of the transmission also contributed to receiving low-quality data. The Douglas Argos filter successfully excluded the largest errors while retaining a large amount of data when the threshold was set to the local scale (two km). Discussion Filter selection requires knowledge about the movement patterns and behavior of the species of interest, and the parametrization of the selected filter typically requires a trial and error approach. Selecting the proper filter reduces the errors while retaining a large amount of data. However, the post-processed data typically includes large positional errors; thus, we recommend incorporating Argos error metrics (e.g., error ellipse) or use complex modeling approaches when working with filtered data

Living at the edge: home range patterns of the Buraiga Chimpanzee Community, Kibale National Park, Uganda

Data on space-use patterns are essential for understanding species ecology and conservation. Individual chimpanzee communities are known to vary in home range size and habitat use dynamics, reflecting site-specific strategies to differences in resource availability on different landscapes. Here we present home range estimates for the Buraiga chimpanzees of Kibale National Park, Uganda, a community of eastern chimpanzees (Pan troglodytes schweinfurthii) living within the largest remaining population fragment in Uganda. The Buraiga chimpanzees are currently undergoing habituation for research and tourism under the direction of the Uganda Wildlife Authority (UWA). We analyzed 15 months of GPS data (August 2019 – March 2020, and January – July 2022), calculating overall and seasonal home range and core area estimates with two methods, minimum convex polygon (MCP) and kernel density estimates (KDE). Home range was estimated to cover an area of 15.77 km2 (95% KDE), and 24.90 km2 (100% MCP). Additionally, we found that 15.82% of the Buraiga chimpanzee’s home range overlaps with community-managed land, primarily the Kanyanchu Swamp corridor and adjacent agricultural land. Seasonally, we found that Buraiga chimpanzees used a larger area during dry season months, compared with rainy season months. Documenting how great ape populations utilize increasingly anthropogenically influenced landscapes is important in order to facilitate long-term survival in the face of climate change, habitat fragmentation, and other ongoing threats

Measuring protected-area effectiveness using vertebrate distributions from leech iDNA

Protected areas are key to meeting biodiversity conservation goals, but direct measures of effectiveness have proven difficult to obtain. We address this challenge by using environmental DNA from leech-ingested bloodmeals to estimate spatially-resolved vertebrate occupancies across the 677 km 2 Ailaoshan reserve in Yunnan, China. From 30,468 leeches collected by 163 park rangers across 172 patrol areas, we identify 86 vertebrate species, including amphibians, mammals, birds and squamates. Multi-species occupancy modelling shows that species richness increases with elevation and distance to reserve edge. Most large mammals (e.g. sambar, black bear, serow, tufted deer) follow this pattern; the exceptions are the three domestic mammal species (cows, sheep, goats) and muntjak deer, which are more common at lower elevations. Vertebrate occupancies are a direct measure of conservation outcomes that can help guide protected-area management and improve the contributions that protected areas make towards global biodiversity goals. Here, we show the feasibility of using invertebrate-derived DNA to estimate spatially-resolved vertebrate occupancies across entire protected areas

Effectiveness of Wildlife Mitigation Treatments Along the Nelsonville Bypass

SJN 135024The Nelsonville Bypass is a 9 mile stretch of U.S. Route 33 that runs through the Wayne National Forest, an area high in species diversity and home to several threatened and endangered species. The motorist safety, economic and conservation values of building effective mitigation features that reduce vehicle-wildlife collisions along the bypass have been nationally recognized. Mitigation features include: high and low fencing to reduce wildlife trespass into the right-of-way (ROW), uni-directional jump outs for wildlife exit from the ROW, underpasses and ecopassages to maintain habitat connectivity across the highway, high-mast lighting to lure bats above traffic flow, and replacement of wetlands and bat roosting habitat. Our two-year study employed road surveys, continuous monitoring of jump outs and wildlife passages, population estimations, detailed mapping of fence structures and breaches, and radio telemetry of an endangered target species. Road surveys of the bypass and control highways revealed that the mitigation structures reduced deer-vehicle collisions, but collisions still occurred on the bypass. Although, generally well-constructed, we identified several ways in which the mitigation features could be made more effective. Placement of fencing near the outer boundary of the ROW made it vulnerable to damage from erosion and tree falls, and isolated high-quality habitats within the ROW. Placement of the fence within 30-50 ft. of the roadway on less rugged terrain away from the forest would likely reduce costs of construction and maintenance while allowing wildlife access to habitat within the ROW. We also recommended regular maintenance inspections and mowing on both sides of the fencing. Jump outs were effective uni-directional exits, but wildlife, particularly deer, were not compelled to exit the expansive area within the ROW fencing. Placement of the fence with jump outs closer to the road would reduce habitat within the fence and combined with traffic noise may increase jump out use. Large wildlife underpasses and crossings were well used by a variety of mammal species. Smaller mammals used the small wildlife ecopassages. Reptiles and amphibians avoided the use of underpasses and road mortality rates of amphibians were high on Ohio State Route 78 (tributary road) near wetlands. Placement and passage design were contributing factors to high amphibian mortality. Radio-tracking of rattlesnakes discovered that snakes easily trespassed the small wildlife fencing and used the habitat within the ROW, likely because it was warmer than the surrounding forested habitat. No road mortality or attempted road crossings by rattlesnakes were detected. Finally, while bats foraged near the lights, most species were detected with equal frequency at different heights under the lighting. Our report details these findings and provides additional recommendations to improve design and construction of wildlife mitigation features both along the Nelsonville Bypass, and for future design of mitigation features for roadways in high-density wildlife areas

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Relative Importance of Habitat Characteristics and Interspecific Relations in Determining Terrestrial Carnivore Occurrence

Carnivores act as top-down regulators in terrestrial ecosystems, and their occurrence and relative abundance is a result of complex interactions between food and habitat availability, human pressure (e.g., trapping, hunting, roadkill), and intraguild interactions (competition, predation). Eastern United States has a long history of human impact, which resulted in an altered carnivore community. Specifically, Ohio presents an interesting case for evaluating the relative roles of interspecific relations and habitat characteristics for shaping the carnivore community, as its carnivore community has a unique dynamics and composition: invasive coyote and red fox (Vulpes vulpes), and native bobcat (Lynx rufus), currently recovering and expanding its range, gray fox (Urocyon cinereoargenteus) declining at a fast pace, and the generalist raccoon (Procyon lotor) and Virginian opossum (Didelphis virginiana). We used 50 camera traps to collect presence/absence data in southeastern Ohio, USA. We hypothesized potential interactions between the six carnivores, and used land cover variables, as well as occupancy probabilities of interacting species, to parameterize to single-species occupancy models. We found that landscape composition at three different scales (500 and 1000 m buffer around camera locations, and 3 × 3 km grid cell) had little effect on species occurrence. We identified strong negative interspecific relations between carnivores, with bobcat occurrence being influenced by presence of coyotes, red fox occurrence by gray foxes, and raccoon occurrence by Virginia possums. While these findings cannot discriminate between habitat partitioning (spatial or temporal) and competition (direct or interference), they lend support to complex dynamics between invasive coyotes and red foxes and recovering (bobcat) and declining (gray fox) native carnivore species. In particular, the negative relation between the apex predator in our system, C. latrans, and L. rufus, raise further questions on whether direct competition from coyotes has the potential to slow bobcat population recovery. In the context of regulated trapping (ongoing for gray fox and potential season for bobcat), a better understanding of the carnivore intraguild relations can inform management and conservation actions targeted at minimizing the impact of competition on at-risk native species from non-native species

Relative Importance of Habitat Characteristics and Interspecific Relations in Determining Terrestrial Carnivore Occurrence

© 2018 Rich, Thompson, Prange and Popescu. Carnivores act as top-down regulators in terrestrial ecosystems, and their occurrence and relative abundance is a result of complex interactions between food and habitat availability, human pressure (e.g., trapping, hunting, roadkill), and intraguild interactions (competition, predation). Eastern United States has a long history of human impact, which resulted in an altered carnivore community. Specifically, Ohio presents an interesting case for evaluating the relative roles of interspecific relations and habitat characteristics for shaping the carnivore community, as its carnivore community has a unique dynamics and composition: invasive coyote and red fox (Vulpes vulpes), and native bobcat (Lynx rufus), currently recovering and expanding its range, gray fox (Urocyon cinereoargenteus) declining at a fast pace, and the generalist raccoon (Procyon lotor) and Virginian opossum (Didelphis virginiana). We used 50 camera traps to collect presence/absence data in southeastern Ohio, USA. We hypothesized potential interactions between the six carnivores, and used land cover variables, as well as occupancy probabilities of interacting species, to parameterize to single-species occupancy models. We found that landscape composition at three different scales (500 and 1000 m buffer around camera locations, and 3 × 3 km grid cell) had little effect on species occurrence. We identified strong negative interspecific relations between carnivores, with bobcat occurrence being influenced by presence of coyotes, red fox occurrence by gray foxes, and raccoon occurrence by Virginia possums. While these findings cannot discriminate between habitat partitioning (spatial or temporal) and competition (direct or interference), they lend support to complex dynamics between invasive coyotes and red foxes and recovering (bobcat) and declining (gray fox) native carnivore species. In particular, the negative relation between the apex predator in our system, C. latrans, and L. rufus, raise further questions on whether direct competition from coyotes has the potential to slow bobcat population recovery. In the context of regulated trapping (ongoing for gray fox and potential season for bobcat), a better understanding of the carnivore intraguild relations can inform management and conservation actions targeted at minimizing the impact of competition on at-risk native species from non-native species

Author Correction: Roadkill and space use data predict vehicle-strike hotspots and mortality rates in a recovering bobcat (Lynx rufus) population (Scientific Reports, (2019), 9, 1, (15391), 10.1038/s41598-019-50931-5)

An amendment to this paper has been published and can be accessed via a link at the top of the paper