The population ecology of some woodland carabid beetles, with particular reference to their dispersive behaviour

The mobility of carabid beetles in the field has been studied by a number of researchers in recent years, but the small scale movements are still poorly understood. The populations of five species of carabid beetles living in a Surrey oakwood were therefore investigated using pitfall trapping and individual marking techniques over a period of three years.Five aspects of the complications associated with the interpretation of pitfall trapping and mark-release-recapture studies were investigated: (i) baiting of the traps by the catch itself, (ii) escape ability of captured beetles, (iii) changes in behaviour following overlong procedures between capture and release, (iv) density effects produced in trapping, and (v) effects of marking procedures on behaviour and survival. No effects could be demonstrated for (i), (iv) and (v). However, the escape rate in Nebria brevicollis was shown to be very high, and the behaviour of the same species affected by the length of time between capture and subsequent release.More than 3000 recaptures of marked beetles were made. Survival into a second breeding season was found to be commonplace in all five species; a few even entered a fourth. The distributions of the beetles within the study area were aggregated, particularly so in Nebria, where it was also shown that the beetles tend to remain in the areas where they are in the highest densities. Distributions changed little with season.Peak displacement rates were associated with the breeding seasonin Nebria but, whereas this fell off with the onset of winter in first season beetles, the level remained high in second season individuals. Pterostichus madidus exhibited a significant lack of displacement with time, except with males during the breeding season. Greatest activity and dispersal was found in August in first season males, but June and July with second season. Abax parallelepipedus beetles were found to be most active early in the season. Very few beetles of the species were found to disperse 100 metres or more within the study area. The concept of home range was examined in relation to ground beetles. Site attachment could not be demonstrated in any species, although other aspects of the trapping results indicated some form of home ranging behaviour.<p

Estatus y conservación de los coleópteros saproxílicos en Europa

The European Red List consists of a selection of 436 saproxylic beetles native to Europe or naturalised in Europe before AD 1500. Red List assessments were made at two regional levels: for geographical Europe and for the 27 Member States of the European Union. Overall nearly 11% of the assessed saproxylic beetles are considered threatened in all Europe, while at the EU 27 level, 14% are threatened. A further 13% of saproxylic beetles are considered Near Threatened. However, for more than a quarter (28%) of the species, there were not enough scientific information to evaluate their risk of extinction and they were classified as Data Deficient. Almost 14% of the species assessed have declining populations. Approximately 27% are thought to be more or less stable, and only 2% are increasing. The population trend for 249 species (57%) remains unknown. Saproxylic beetles in Europe are mainly threatened by habitat loss in relation to logging and wood harvesting and the decline of veteran trees throughout the landscape, as well as the lack of land management targeted at promotion of recruitment of new generations of trees. It is hoped that the results of this Red List will stimulate research, monitoring and conservation action of saproxylic beetles at the local, regional and international levels

Orden Psocoptera

Los Psocoptera son un grupo de insectos hemimet ábolos de vida libre, caracterizados por tener mandíbulas masticadoras generalment e asimétricas, que funcionan junto con la maxila a modo de mortero para rascar el sustrato y triturar el alimento. Las antenas son largas y filiformes y la cabeza ancha, con ojos globulares prominentes y tres ocelos. Se dividen en dos grandes grupos informales, los "piojos de la corteza", generalmente de un tamaño entre 5-10 mm, con alas plegadas en reposo en forma de tejadillo, que se encuentran habitualmente en hojarasca, bajo la cort eza o bajo piedras; y los "piojos de los libros", de menor tamaño (menos de 2 mm), ápteros, generalmente despigmentados y asociados a productos almacenados u otros ambientes antrópicos.Peer reviewe

Thames and Chilterns Parkland and wood pastures with veteran trees : pahse 1 - a provisional inventory 2002/03

Includes bibliographical referencesAvailable from British Library Document Supply Centre- DSC:3775. 10607(no 520) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

European red list of saproxylic beetles

Brochure disponible: It is available online at http://ec.europa.eu/environment/nature/conservation/species/redlist and http://www.iucnredlist.org/initiatives/europ