Biological Earth observation with animal sensors.

Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmen-tal change

Determination of material's tightening force with chipper knife

Chippers designed for chopping wood at the sawmill waste, produce of wood chips could be used in agriculture; they used at development of lands derived from the rotation overgrown with undergrowth and bushes. The improvement and optimization of parameters of chipper RB-750 with a combined working body, the effectiveness of which depends on a number of structural factors: the angle tightening angle pinch location shearbar and others is conducted in Vyatka State Agricultural Academy. Angle of incidence in the cutting process changes its value and affects the strength of the material tightening with knife. The maximum value of a tightening force is possible at the smallest impact angle, but it degrades the quality of the finished product. To justify the design parameters of the working body theoretical research were conducted with the consideration of two major cases: when the angle of incidence is less and more than 90°. The obtained dependences allow to determine the parameters of the cutting pair providing material delay at changing cutting conditions: the ratio of the components of the cutting force; the coefficient of friction of material on the surface of working bodies. Experimental studies on confirming of the theoretical assumptions were made in a laboratory machine which allows to register the effect of a tightening of sample material with knives of grinding drum of the working body. Completed experiments yielded a regression model that characterizes the effect of investigated factors on the strength of a material tightening with knives. The experimental results confirm the theoretical assumptions put forward and allow to draw conclusions about the optimal values of the factors: angle of delaying у = 4.5...4.8°; location of shearbar below the horizontal axis of the drum on 20...21 mm; angle of crushing material х = 30°

Quick-quick-slow: the foxtrot migration and dynamic non-breeding range

ABSTRACTBackgroundTo conserve bird species threatened by climate change, it is important to understand how environmental factors affected by climate change, such as snow cover, impact their ranges. While this problem is fairly well understood for breeding areas, it remains poorly understood for non-breeding areas. In non-breeding areas, seasonal cycles can strongly influence the distribution of resources during winter. If birds adapt to such changes, they may result in seasonal and directional movement of birds within their non-breeding range. In this case, birds would experience a unique migration pattern - rapid migration between breeding and non-breeding habitats versus a slow migration pattern within their non-breeding range. Their non-breeding range would therefore be dynamic, with potentially important consequences for our understanding of population densities and non-breeding ranges.MethodsBetween 2013-2021, we tracked 43 adult Rough-legged buzzards with solar GPS-GSM loggers. We analyzed their behavior, determined whether the birds showed any directional return migrations during the non-breeding season, and evaluated the differences between the slow migration within their winter range and the quick migration between breeding and non-breeding areas. We also analyzed the vegetation cover of the areas crossed during quick and slow migrations and the role of snow cover in winter migrations.ResultsOur findings revealed that after a quick fall migration through the taiga zone, Rough-legged buzzards continue to migrate during the non-breeding season, albeit at a slower pace across the wooded fields they select as habitat. They avoid complete snow cover and move to escape the progression of the snow cover line from northeast to southwest and back during the winter. As a consequence, Rough-legged buzzards have a dynamic winter range. Thus, the migration pattern of these birds comprises alternating quick and slow phases, resembling the foxtrot dance, which we have named the ‘foxtrot’ migration pattern. Due to this pattern, their winter range displays a dynamic shift of the seasonal center of the population distribution over 1000 km towards the southwest and back throughout the winter.ConclusionsOur study uncovered a novel bird migration pattern postulated to exist before but poorly understood. This ‘foxtrot migration’ likely occurs in many migratory species inhabiting winter areas with pronounced seasonal cycles. Our findings have implications for conservation efforts in the Anthropocene, where environmental factors such as snow cover can change rapidly and have cascading effects on bird migration. We recommend presenting dynamic winter ranges in species descriptions and range maps so ecologists can use them to develop effective conservation strategies.</jats:sec

Changes in dental wear and breakage in arctic foxes (<i>Vulpes lagopus</i>) across space and time: evidence for anthropogenic food subsidies?

Increased human presence in the Arctic may affect its vulnerable ecosystems. Effects on arctic and red foxes provide notable examples. Both have been documented to take anthropogenic subsidies when available, which can change diet and ranging patterns in complex ways that can either benefit or harm populations, depending on the situation. Understanding this complexity requires new tools to study impacts of increasing human presence on endemic mammals at high latitudes. We propose that dental ecology, specifically tooth wear and breakage, can offer important clues. Based on samples of arctic foxes ( Vulpes lagopus (Linnaeus, 1758)) trapped prior to ( n = 78) and following ( n = 57) rapidly growing human presence on the Yamal Peninsula, Russia, we found that foxes trapped recently in proximity to human settlement had significantly less tooth wear and breakage. This is likely explained by a dietary shift from consumption of reindeer ( Rangifer tarandus (Linnaeus, 1758)) carcasses including bone to softer human-derived foods, especially when preferred smaller prey (e.g., West Siberian lemmings, Lemmus sibiricus (Kerr, 1792), and arctic lemmings, Dicrostonyx torquatus (Pallas, 1778)) are unavailable. These results suggest that tooth wear and breakage can be a useful indicator of the consumption of anthropogenic foods by arctic foxes. </jats:p

Predator-prey interactions between the arctic fox and tundra nesting birds in space and time: first results of an ongoing circumpolar initiative

International audienc

Status and trends of circumpolar peregrine falcon and gyrfalcon populations

The peregrine falcon (Falco peregrinus) and the gyrfalcon (Falco rusticolus) are top avian predators of Arctic ecosystems. Although existing monitoring efforts are well established for both species, collaboration of activities among Arctic scientists actively involved in research of large falcons in the Nearctic and Palearctic has been poorly coordinated. Here we provide the first overview of Arctic falcon monitoring sites, present trends for long-term occupancy and productivity, and summarize information describing abundance, distribution, phenology, and health of the two species. We summarize data for 24 falcon monitoring sites across the Arctic, and identify gaps in coverage for eastern Russia, the Arctic Archipelago of Canada, and East Greenland. Our results indicate that peregrine falcon and gyrfalcon populations are generally stable, and assuming that these patterns hold beyond the temporal and spatial extents of the monitoring sites, it is reasonable to suggest that breeding populations at broader scales are similarly stable. We have highlighted several challenges that preclude direct comparisons of Focal Ecosystem Components (FEC) attributes among monitoring sites, and we acknowledge that methodological problems cannot be corrected retrospectively, but could be accounted for in future monitoring. Despite these drawbacks, ample opportunity exists to establish a coordinated monitoring program for Arctic-nesting raptor species that supports CBMP goals