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Measures favouring saproxylic beetles in a forest reserve The goal of this study is to propose conservation measures aiming at favouring saproxylic beetle populations, considering the general management of a forest reserve. The study site is a periurban forest above the city of Neuchâtel in the Swiss Jura. The studied habitats are oak and beech forests alternating with dry meadow patches and black pine (Pinus nigra) plantations. The general management goal of this forest reserve is to conserve rare plant associations and to preserve characteristical fauna and flora. In order to achieve these goals, the following management actions were undertaken: preserve open habitats, reduce black pine occurrence, restore and enhance oak forest and preserve islands of old growth. An inventory of four beetle families (Cerambycidae, Buprestidae, Lucanidae and Cetoniidae) was made by means of direct collection. Between 2004 and 2009, twenty-five collecting tours lasting for an average of 1 hour 45 minutes were performed from the beginning of May to the beginning of July. Fifty-two beetle species were caught and grouped in six categories based on their larval ecology. For each of them, enhancing actions were proposed, potential conflicts between saproxylic beetle conservation and general management actions were discussed. In order to find a balance between sometimes contradictory actions, the best solution to promote an optimal biodiversity is a patchwork of forest and open biotopes. As far as saproxylic beetles are concerned, tree diversity should be enhanced and old trees preserved. In the open areas, old bushes growing in the edges should not be removed.

In Europe, insects represent approximately ¾ of the forest animal species. Thanks to their appreciable numbers and their varied diets, they render numerous services to the forest. By accelerating the recycling of organic material they contribute to the fertility of the soil. A rich and diversified entomological fauna reduces the risk of a proliferation of pests, thanks to predation and competition. Last but not least, many forest insects are in addition active pollinators. Many very specialized forest insects lacking a great mobility have become exceedingly rare and survive only in a few isolated reservoirs. The forest entomological biodiversity must be preserved, quite as much for ethical reasons as for the services which it provides. In order to do this, it is necessary to conserve a structurally diversified forest with many old trees, hollow trunks and snags, clearings and multi-storeyed forest edges.

The effect of fires on Cerambycidae, Buprestidae and Lucanidae were studied at 23 sites within a chestnut forest in southern Switzerland. We compared six unburnt sites, two freshly burnt sites, eight sites which burned once at different times in the last 30 years, and seven sites where fires occurred repeatedly in the last 30 years. The diversity and the species composition of the three xylobiont families were related to various ecological variables at two levels of spatial scale, a small scale of 0.25 ha and a large scale of 6.25 ha. These variables were: fire frequency, time since the last fire, clear cutting after the fire, forest structure, amount of dead wood, and habitat mosaic. The fire does not have a direct effect on the xylobiont beetles community at small scale; however, fire has an indirect effect by maintaining a relatively open forest structure. The mosaic of forest areas burnt with different frequencies and at different times was an important factor influencing species richness and species composition at the large spatial scale. Data presented here supports the strategy to conserve the diversity and includes species composition of xylobiont fauna in deciduous forests: (i) at small spatial scale, to maintain highly structured and relatively open stands with large amounts of dead wood and big oak trees; (ii) at large spatial scale, to favour a mosaic of different forest habitats and successional stages. A forest offering a good structural diversity is important for maintaining landscape complexity and thus a high species richness of xylophagous beetles.

This study estimates the influence of renewed coppicing with standards on the abundance and diversity of four beetle families(Buprestidae, Cerambycidae, Lucanidae and phytophagous Scarabaeidae) in a forest where this practice was abandoned. The study was conducted from mid-May to mid-August 1998 in the region of Ferreyres - Moiry (VD). Eight sites were chosen for the sampling of these insects, which were captured by means of window and water traps. Coppicing with standards is very favourable to these beetles, which are often thermophilous. In such places, they find stumps and branch heaps, which are suitable for the development of their larvae. On the contrary, in abandoned coppice, the abundance and diversity of the selected beetles are very low. This kind of forest is extremely dark and unsuitable for thermophi-lous species. Renewed coppicing with standards is, therefore, very recommendable. It creates very favourable biotopes for the beetles, where they find both light and deadwood and which, to a certain extent, recreate the biotopes naturally formed by the fall of old trees in primitive forests.

Sylvie, Barbalat (2012): Note brève Capture de Ripidius quadriceps (Coleoptera Ripiphoridae) dans le canton de Neuchâtel. Entomo Helvetica 5: 161-162, DOI: 10.5169/seals-986134