The burrow system of the common vole (M. arvalis, Rodentia) in Switzerland

Fifty burrow systems of Microtus arvalis were excavated, from October 2006 to August 2007 in wildflower fields and quasi-natural habitats in five areas near Bern, Switzerland. They comprise an aboveground part, which is longer in spring/summer, and a subterranean part, which is longer in autumn/winter. Three main construction types exist: (a) linear burrows, (b) compact and tight networks, and (c) structures containing both a compact network around the nest and linear parts elsewhere. The subterranean length was on average 16.9m (range: 0.5-70.2m) and aboveground length 39.4m (range: 0-95m). Numbers of intersections, dead ends, and openings correlate significantly with subterranean burrow length. Nests and food caches were located at a maximal depth and mostly in a central position, as revealed by graph theor

A New System for Automatic Radiotracking of Small Mammals

We developed a radiotracking system for automatic and continuous data collection, which allows the radiotracking of several animals at the same time. Based on a system controller, 3 fixed antennas, and small-size radiotransmitters (<2 g, 14 by 12 by 4 mm), the system has the capacity to record several individuals continuously at intervals of <5 min. Antennas, positioned at fixed points in the field, forward the signals from tagged animals to the system controller, where data are collected. The coordinates of the individual's locations are calculated through triangulation on the basis of the angles of incidence from the transmitter signal to each antenna. Transmitters are individually identified by the chronological sequence of their signals. Field tests with Microtus arvalis show the utility of the new technique and possibilities for the syste

Écologie des populations de petits rongeurs dans des jachères florales dans l’ouest de la Suisse

Small mammal communities on four sown wild flower areas in western Switzerland were studied from spring to autumn 2005 using the capture-recapture method. We trapped 666 animals belonging to Microtus arvalis, Apodemus sylvaticus, Apodemus flavicollis and Crocidura russula. M. arvalis, the most abundant species, reached a peak of 581 animals/ha known to be alive (MNA) on one area in late September. Spring populations of M. arvalis were very low on all fields. A preliminary study in 2003-2004 showed a very low number of animals known to be alive during the winter months and a similar population growth in spring. Population turnover was generally high with up to 81 % of the population renewed in a one-week period (August). On all fields, there was a surplus of female M. arvalis. In August and September, the difference from 1: 1 ratio was significant in one field, apparently a result of differential survival rate and recruitment between sexes. There was no significant difference in body mass between adult females and adult males. The second most frequent species, A. sylvaticus reached densities of up to 225 animals/ha on one area, but only 60-100 animals/ha, on the other three sites.Des communautés de petits mammifères ont été étudiées dans des jachères florales en Suisse romande du printemps à l’automne 2005 au moyen du piégeage par capture et recapture. Au total, 666 individus ont été capturés, appartenant aux espèces suivantes : Microtus arvalis, Apodemus sylvaticus, Apodemus flavicollis et Crocidura russula. M. arvalis, l’espèce la plus abondante, a atteint un maximum de 581 animaux/ha (MNA MNA : minimum number alive) sur une parcelle en septembre. Au printemps, les populations de M. arvalis furent très basses sur toutes les parcelles. Une étude préliminaire en 2003-2004 a montré que le nombre d’animaux était très bas en hiver et ne s’accroissait qu’à la fin du printemps. Le renouvellement (turnover) des populations fut généralement élevé, dépassant 80 % en une semaine en août. Sur toutes les parcelles, un surplus de femelles de M. arvalis fut observé. En août et septembre, la différence par rapport à un sex-ratio de 1 : 1 fut statistiquement significative, due probablement à des taux de survie différents entre mâles et femelles. Aucune différence significative entre les poids des mâles et femelles adultes ne fut observée. La deuxième espèce la plus fréquente, A. sylvaticus, atteignit une densité de 225 individus/ha sur une parcelle, mais seulement 60-100 individus/ha sur les trois autres site

Ocean-related options for climate change mitigation and adaptation: A machine learning-based evidence map protocol

BackgroundOcean-related options (OROs) to mitigate and adapt to climate change are receiving increasing attention from practitioners, decision-makers, and researchers. In order to guide future ORO development and implementation, a catalogue of scientific evidence addressing outcomes related to different ORO types is critical. However, until now, such a synthesis has been hindered by the large size of the evidence base. Here, we detail a protocol using a machine learning-based approach to systematically map the extent and distribution of academic evidence relevant to the development, implementation, and outcomes of OROs.MethodTo produce this systematic map, literature searches will be conducted in English across two bibliographic databases using a string of search terms relating to the ocean, climate change, and OROs. A sample of articles from the resulting de-duplicated corpus will be manually screened at the title and abstract level for inclusion or exclusion against a set of predefined eligibility criteria in order to select all relevant literature on marine and coastal socio-ecological systems, the type of ORO and its outcomes. Descriptive metadata on the type and location of intervention, study methodology, and outcomes will be coded from the included articles in the sample. This sample of screening and coding decisions will be used to train a machine learning model that will be used to estimate these labels for all the remaining unseen publications. The results will be reported in a narrative synthesis summarising key trends, knowledge gaps, and knowledge clusters

From Sea to Sea: Canada's Three Oceans of Biodiversity

Evaluating and understanding biodiversity in marine ecosystems are both necessary and challenging for conservation. This paper compiles and summarizes current knowledge of the diversity of marine taxa in Canada's three oceans while recognizing that this compilation is incomplete and will change in the future. That Canada has the longest coastline in the world and incorporates distinctly different biogeographic provinces and ecoregions (e.g., temperate through ice-covered areas) constrains this analysis. The taxonomic groups presented here include microbes, phytoplankton, macroalgae, zooplankton, benthic infauna, fishes, and marine mammals. The minimum number of species or taxa compiled here is 15,988 for the three Canadian oceans. However, this number clearly underestimates in several ways the total number of taxa present. First, there are significant gaps in the published literature. Second, the diversity of many habitats has not been compiled for all taxonomic groups (e.g., intertidal rocky shores, deep sea), and data compilations are based on short-term, directed research programs or longer-term monitoring activities with limited spatial resolution. Third, the biodiversity of large organisms is well known, but this is not true of smaller organisms. Finally, the greatest constraint on this summary is the willingness and capacity of those who collected the data to make it available to those interested in biodiversity meta-analyses. Confirmation of identities and intercomparison of studies are also constrained by the disturbing rate of decline in the number of taxonomists and systematists specializing on marine taxa in Canada. This decline is mostly the result of retirements of current specialists and to a lack of training and employment opportunities for new ones. Considering the difficulties encountered in compiling an overview of biogeographic data and the diversity of species or taxa in Canada's three oceans, this synthesis is intended to serve as a biodiversity baseline for a new program on marine biodiversity, the Canadian Healthy Ocean Network. A major effort needs to be undertaken to establish a complete baseline of Canadian marine biodiversity of all taxonomic groups, especially if we are to understand and conserve this part of Canada's natural heritage

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Expériences de capture et recapture chez le Campagnol terrestre Arvicola terrestris scherman Shaw (Mammalia - rodentia)

Eine «Fang -Wiederfangmethode » wird für die Schermaus, Arvicola terrestris scherman Shaw, beschrieben. Sie besteht darin, dass man «Sherman» - Fallen in Seitenkammern, senkrecht zur Gangsaxe, legt. Diese Méthode ermöglicht den Fang von mehr als 90 % der Gesamtpopulation innert 3 Tagen. Die Zahl der Wiederfänge und die Zahl der verschiedenen Fallen, die von den einzelnen Tieren besucht werden, genügen um die Populationsdichte zu schätzen und die Aktionsräume sowie die Zusammensetzung der Familien, die sie bewohnen, zu bestimmen. Die Fänge, die während verschiedenen Perioden gemacht wurden, geben Auskunft über allfällige Veränderungen, die in der Populationsstruktur stattgefunden haben. Einige Beispiele werden dargestellt und diskutiert.A method of capture and recapture of the fossorial form of Water vole, Arvicola terrestris scherman Shaw, is described. It consists in placing «Sherman» traps in lateral groves perpendcularly to the axis of the galleries. This technique leads to the capture within 3 days of over 90 % of the total population. The number of recaptures and the number of different traps visited by each animal are sufficient to estimate the population density and to determine the home ranges as well as the size of the family groups that occupy them. Trapping done at different periods supply information about the changes having occurred in the structure of the population. Some examples are given and discussed.Une méthode de capture et recapture de la forme fouisseuse du campagnol terrestre, Arvicola terrestris scherman Shaw, est décrite. Elle consiste à disposer des trappes «Sherman» dans des fosses latérales perpendiculairement à l’axe des galeries. Cette technique permet de capturer en 3 jours plus de 90 % de la population totale. Le nombre de recaptures et le nombre de trappes différentes visitées par chaque individu sont suffisants pour estimer la densité de population et déterminer les domaines vitaux ainsi que les groupes familiaux qui les occupent. Des piégeages effectués à différentes périodes fournissent des renseignements au sujet des changements intervenus dans la structure des populations. Quelques exemples sont donnés et discutés.Airoldi Jean-Pierre. Expériences de capture et recapture chez le Campagnol terrestre Arvicola terrestris scherman Shaw (Mammalia - rodentia). In: La Terre et La Vie, Revue d'Histoire naturelle, tome 30, n°1, 1976. pp. 31-51

A New System for Automatic Radiotracking of Small Mammals

We developed a radiotracking system for automatic and continuous data collection, which allows the radiotracking of several animals at the same time. Based on a system controller, 3 fixed antennas, and small-size radiotransmitters (<2 g, 14 by 12 by 4 mm), the system has the capacity to record several individuals continuously at intervals of <5 min. Antennas, positioned at fixed points in the field, forward the signals from tagged animals to the system controller, where data are collected. The coordinates of the individual's locations are calculated through triangulation on the basis of the angles of incidence from the transmitter signal to each antenna. Transmitters are individually identified by the chronological sequence of their signals. Field tests with Microtus arvalis show the utility of the new technique and possibilities for the system

The burrow system of the common vole (M. arvalis) in Switzerland

Abstract Fifty burrow systems of Microtus arvalis were excavated, from October 2006 to August 2007 in wildflower fields and quasi-natural habitats in five areas near Bern, Switzerland. They comprise an aboveground part, which is longer in spring/summer, and a subterranean part, which is longer in autumn/winter. Three main construction types exist: (a) linear burrows, (b) compact and tight networks, and (c) structures containing both a compact network around the nest and linear parts elsewhere. The subterranean length was on average 16.9 m (range: 0.5–70.2 m) and aboveground length 39.4 m (range: 0–95 m). Numbers of intersections, dead ends, and openings correlate significantly with subterranean burrow length. Nests and food caches were located at a maximal depth and mostly in a central position, as revealed by graph theory.</jats:p