Saproxylic Beetle Species Research Articles

Effectiveness of local conservation management is affected by landscape properties: Species richness and composition of saproxylic beetles in boreal forest clearcuts

Landscape context is known to affect species diversity patterns and can even influence the effectiveness of local conservation management in agricultural landscapes. For other land uses, like forestry, landscape effects are poorly known. We aimed to determine whether landscape composition modifies the response of saproxylic beetle species to local habitat and conservation management, with focus on dead wood and prescribed fire, in managed boreal forest landscapes. We surveyed beetles on 32 clearcuts in central Sweden. We measured local (fire, dead wood, flower resources, patch size) and landscape factors (fire, dead wood within 1–2kmradius), and analysed interactions between these in mixed models. The response was species richness of beetles with different habitat specialization – conifer specialists, deciduous specialists, flower visitor and pyrophilous species, and abundance of a red-listed species, Tragosoma depsarium. Local and landscape factors, as well as interactions between them, affected species richness patterns. Prescribed fire and amount of dead wood, both on local and landscape scale, affected species richness and composition of several groups. There were interactions between local and landscape factors in five models out of six. Locally, we observed a positive response to flower richness for several groups, while the response to prescribed fire and dead wood amounts typically was affected by landscape factors. The results suggest that effectiveness of local conservation management is affected by landscape properties; the positive effects of local dead wood amounts and burning occurred on clearcuts in landscapes with large amounts of dead wood, but not in landscapes with small amounts of dead wood.

Making the invisible visible: determining an accurate national distribution of Elater ferrugineus in the United Kingdom using pheromones

Abstract To date, conservation‐status saproxylic beetle species in the UK have been monitored by chance findings or by monitor‐based observational studies. Here, using Elater ferrugineus as our target species, we present the first national distribution survey carried out in the UK or across mainland Europe on such a species using chemicals produced by the insect. Over 3 years, mark‐release‐recapture studies were performed across the UK, using 416 lured (pheromone) traps monitored by volunteer recorders; the first survey in Europe to do so. Traps were baited with 7‐methyloctyl‐ (Z)‐4‐decenoate, a compound previously identified as a female sex pheromone. The results were used to plot a distribution map and investigate factors that may influence the distribution, including summer temperatures, possible habitat availability and larval food source. The survey revealed a south‐eastern distribution of E. ferrugineus in the UK, which was suggested by previous casual studies. A correlative model was fitted to the data, indicating that 55% of the variation in the distribution of E. ferrugineus was explained by climatic variables (temperature and wind speed).

Use of novel attraction compounds increases monitoring success of a rare beetle, Elater ferrugineus

Abstract The use of pheromones to determine distributions of rare saproxylic insects is an increasingly popular technique. Pheromones may, however, also be used to elucidate the biology of these cryptic species, a vital requirement if they are to be accurately monitored and conserved. We used non‐invasive aerial trapping to compare the effectiveness of chemicals produced by Elater ferrugineus L (Coleoptera: Elateridae), namely 7‐methyloctyl (Z)‐4‐decenoate (the female‐produced sex pheromone), and male compounds (geranyl and neryl acetone and 6‐methyl‐5‐heptene‐2‐one). The male compounds were identified using headspace analysis by solid phase micro‐extraction gas chromatography‐mass spectrometry. We discovered that males only produce these two compounds after having been attracted to a female, and that this serves to attract further males to a female. Such compounds do not appear to attract females but for a species that has a short activity period and is non‐feeding in the adult stage, may ensure breeding success when populations are low. By marking all beetles caught, we were able to demonstrate that recapture rate using this method is low (approximately 11% of total captures annually). Therefore, the method does not limit dispersal or breeding opportunities, making it a valuable tool for monitoring endangered saproxylic beetle species.

Are biodiversity patterns of saproxylic beetles shaped by habitat limitation or dispersal limitation? A case study in unfragmented montane forests

Understanding the processes that shape biodiversity patterns is essential for ecosystem management and conservation. Local environmental conditions are often good predictors of species distribution and variations in habitat quality usually positively correlate to species richness. However, beside habitat limitation, species presence-absence may be constrained by dispersal limitation. We tested the relative importance of both limitations on saproxylic beetle diversity, using forest continuity as a surrogate for dispersal limitation and stand maturity as a surrogate for habitat limitation. Forest continuity relies on the maintenance of a forest cover over time, while stand maturity results in the presence of old-growth habitat features. Forty montane beech-fir forests in the French pre-Alps were sampled, under a balanced sampling design in which forest continuity and stand maturity were crossed. A total of 307 saproxylic beetle species were captured using flight-interception traps and Winkler–Berlese extractors. We explored the response of low- versus high-dispersal species groups to forest continuity and stand maturity. Saproxylic beetle diversity increased significantly with stand maturity and was mostly influenced by variables related to deadwood diversity at the stand scale and suitable habitat availability at the landscape scale. Surprisingly, no evidence of dispersal limitation was found, as diversity patterns were not influenced by forest continuity and associated variables, even for low-dispersal species. Our study demonstrates that in an unfragmented forest landscape, saproxylic beetles are able to colonize recent forests, as long as local deadwood resources are sufficiently diversified (e.g. tree species, position, diameter and/or decay stage).

Target and non-target beetles in semiochemical-baited cross vane funnel traps used in monitoring Bursaphelenchus xylophilus (PWN) vectors in pine stands

In 2007–2012 we assessed dendrobiotic insects at three locations in stands of Pinus nigra, Pinus halepensis and Pinus sylvestris in Slovenia. The samples were collected from May to November using four (three in 2007) cross vane funnel traps per location with wet collecting cups and attractants. In 2007 we used ethanol+α-pinene, and from 2008 to 2010, ethanol+α-pinene, Pheroprax® (ipsdienol, cis-verbenol, 2-methylbut-3-en-2-ol) and Gallowit® (ipsdienol CAS 14434-41-4, ipsenol CAS 60894-96-4, DMWK CAS 115-18-4, cis-verbenol CAS 18881-04-4, α-pinene CAS 80-56-8, ethanol CAS 64-17-5) were used with traps 1.5 m above the ground. In 2011–2012 ethanol+α-pinene and Galloprotect 2D® (Galloprotect F: an aggregation pheromone [2-undecyloxy-1-ethanol] and Galloprotect A: kairomonal substances [ipsenol and 2-methyl-3-buten-1-ol]) were used with traps in the lower canopy. We collected 31,228 individuals from 45 beetle families. Curculinidae (Scolytinae, 23,325) were the most numerous, and the target family Cerambycidae was represented with 1945 specimens from 28 taxa and 25 species. In 2007 Spondylis buprestoides was by far the most abundant species. In 2008–2010 ethanol+α-pinene more effectively attracted S. buprestoides and A. rusticus, whereas Monochamus galloprovincialis showed a clear preference for Gallowit®. In 2011–2012 Galloprotect 2D® attracted significantly more cerambycids than ethanol+α-pinene, and M. galloprovincialis was by far the most numerous species. In addition to cerambycids, other saproxylic beetle species and also scolytine predators (mostly Cleridae, Histeridae, Trogossitidae) were found in the traps, highlighting the need to consider the potential negative impacts of the long-term monitoring of PWN vectors on species with important functional-trophic traits in forests.

Robinia pseudoacacia as a surrogate for native tree species for saproxylic beetles inhabiting the riparian mixed forests of northern Italy

Abstract The felling and leaving of non‐native trees comprise management strategies designed to increase dead wood for saproxylic fauna in forests without affecting native tree species. In northern Italy, the most widespread exotic tree in alluvial forests is the North American Robinia pseudoacacia. We quantified the difference in species composition and abundance among saproxylic beetles of two European broad‐leaved trees, Populus alba and Quercus robur, and the exotic broad‐leaved tree Robinia pseudoacacia. We collected beetles emerging from 29 fallen trunks with a diameter of between 29 and 31 cm and belonging to the second decomposition stage. We identified 249 individuals from 25 saproxylic beetle species. Species richness and composition did not differ among tree species. Although permutational multivariate analysis of variance highlighted significant differences in species composition, linear mixed effect models showed that differences depend exclusively on spatial distances between logs and not on the host tree species. The Morisita‐Horn index and principal coordinate analysis confirmed this pattern. Thus, we found that saproxylic beetles use all dead trees available in the forest, without distinguishing between exotic or native trees but only occupying the nearest ones. From a forest management point of view, this supports the practice of leaving dead wood of exotic trees at restorations for saproxylic beetles.

A Red List of Italian Saproxylic Beetles: taxonomic overview, ecological features and conservation issues (Coleoptera)

The main objectives of this review are: 1) the compilation and updating of a reference database for Italian saproxylic beetles, useful to assess the trend of their populations and communities in the next decades; 2) the identification of the major threats involving the known Italian species of saproxylic beetles; 3) the evaluation of the extinction risk for all known Italian species of saproxylic beetles; 4) the or- ganization of an expert network for studying and continuous updating of all known species of saproxylic beetle species in Italy; 5) the creation of a baseline for future evaluations of the trends in biodiversity conservation in Italy; 6) the assignment of ecological categories to all the Italian saproxylic beetles, useful for the aims of future researches on their communities and on forest environments. The assess- ments of extinction risk are based on the IUCN Red List Categories and Criteria and the most updated guidelines. The assessments have been carried out by experts covering different regions of Italy, and have been evaluated according to the IUCN standards. All the beetles whose larval biology is sufficiently well known as to be considered saproxylic have been included in the Red List, either the autochtho- nous species (native or possibly native to Italy) or a few allochthonous species recently introduced or probably introduced to Italy in his- toric times. The entire national range of each saproxylic beetle species was evaluated, including large and small islands; for most species, the main parameters considered for evaluation were the extent of their geographical occurrence in Italy, and the number of known sites of presence. 2049 saproxylic beetle species (belonging to 66 families) have been listed, assigned to a trophic category (Table 3) and 97% of them have been assessed. On the whole, threatened species (VU + EN + CR) are 421 (Fig. 6), corresponding to 21 % of the 1988 as- sessed species; only two species are formally recognized to be probably Regionally Extinct in Italy in recent times. Little less than 65% of the Italian saproxylic beetles are not currently threatened with extinction, although their populations are probably declining. In forest environments, the main threats are habitat loss and fragmentation, pollution due to the use of pesticide against forest pests, and habitat simplification due to economic forest management. In coastal environments, the main threats are due to massive touristic exploitation such as the excess of urbanization and infrastructures along the seashore, and the complete removal of woody materials as tree trunks stranded on the beaches, because this kind of intervention is considered an aesthetic amelioration of seaside resorts. The number of spe- cies whose populations may become impoverished by direct harvest (only a few of large forest beetles frequently collected by insect traders) is very small and almost negligible. The Red List is a fundamental tool for the identification of conservation priorities, but it is not a list of priorities on its own. Other elements instrumental to priority setting include the cost of actions, the probability of success,and the proportion of the global population of each species living in Italy, which determines the national responsibility in the long-term conservation of that species. In this scenario, information on all species endemic to Italy, to Corso-Sardinia, to the Tuscan-Corsican ar- eas, and to the Siculo-Maltese insular system are given. A short analysis on relationships among beetle species traits, taxonomy, special- ist approaches, and IUCN Categories of Risk is also presented.

Forest restoration to attract a putative umbrella species, the white‐backed woodpecker, benefited saproxylic beetles

Umbrella species are often spatially demanding and have limited ability to adapt to environmental changes induced by human land‐use. This makes them vulnerable to human encroachment. In Sweden, broadleaved trees are disadvantaged by forestry, and commercially managed forests are often deprived of dead wood. This has led to a situation where previously widespread top predators in saproxylic food webs, such as the white‐backed woodpecker (Dendrocopos leucotos), have become species of conservation concern. The white‐backed woodpecker is generally considered an umbrella species, and it has been linked to forests with large volumes of dead wood from broadleaved trees. In recent years, forest stands have been restored for the white‐backed woodpecker, but post‐treatment evaluations have rarely included other species that also occur in broad‐leaved forests (co‐occurring species). Many co‐occurring species are saproxylic beetles. In this study, we collected saproxylic beetles and environmental data in restored and commercially managed forests to evaluate if habitat restoration for the white‐backed woodpecker also benefited other species with similar habitat associations. We found that volumes of coarse woody debris were higher in restored than in commercially managed forests, and that a majority of man‐made snags and downed logs were created from birch trees (Betula spp.). Most spruce trees (Picea abies) were extracted during forest restoration, and this opened up the forest canopy, and created stands dominated by broadleaved trees. Many saproxylic beetles were more common in restored forests, and there were significant differences in species composition between treatments. These differences were largely explained by species traits. Effects of sun‐exposure were particularly important, but many beneficiary species were also linked to dead wood from broadleaved trees. Red‐listed saproxylic beetles showed a similar pattern with more species and individuals in restored sites. The white‐backed woodpecker is still critically endangered in Sweden, but important prey species are already responding to forest restoration at the stand level. We recognize that landscape‐level improvements will be required to bring the white‐backed woodpecker back, but also that the umbrella species concept can provide a useful framework for successful forest restoration as many co‐occurring saproxylic beetle species seemingly benefitted from restoration for the white‐backed woodpecker.

Scale-specific responses of saproxylic beetles: combining dead wood surveys with data from satellite imagery

We investigate relevant scales and cost-efficient methods for measurements of habitat for saproxylic, aspen-associated beetles, in two boreal forest landscapes in south-eastern Norway. We sampled saproxylic beetles with window traps on fresh aspen dead wood and conducted field surveys of dead wood in the surroundings (1, 2 and 3 km radius). In addition, we used maps derived from satellite imagery to extract data on forest age and volume for the same surroundings. We found that species richness of saproxylic beetles was related to dead wood volume estimated by field survey within 1 or 2 km radius from the trapping points. However, the map-derived variable describing area of forest with high levels of deciduous wood volume was the overall best predictor of species richness. The scale of response to this variable differed; species richness of all saproxylic beetles was best predicted by estimates for the 2 km radius whereas richness of species more strongly associated with aspen was best predicted by estimates for the 3 km radius. This might indicate that aspen-associated beetles disperse over larger distances than many other beetles; possibly an adaptation to the scattered distribution and ephemeral nature of aspen dead wood in boreal forests. Our results show that substrate variables must be measured at the scale that is ecologically relevant for the study organism to elicit a response. We also show that remote sensing data -often easy to obtain for large scales—can be used to complement studies of scale-specific responses and thus improve conservation measures for saproxylic beetle species.

Relative importance of habitat characteristics at multiple spatial scales for wood-dependent beetles in boreal forest

Species distributions are influenced by habitat conditions and ecological processes at multiple spatial scales. An understanding of the importance of habitat characteristics at different spatial scales is important when developing biodiversity conservation measures. We investigated the effect of habitat characteristics or amount at three spatial scales on the occurrence of saproxylic (=dead wood-dependent) beetles. Saproxylic beetles were sampled under the bark of dead wood in a managed forest landscape in central Sweden. We modelled the occurrence probability in dead wood items of 44 species (all species occurring in >2 % of the items), based on dead wood item characteristics, forest stand characteristics, and habitat connectivity (i.e. area of potentially suitable forest stands in the surrounding of each stand), using hierarchical Bayesian regression. For the majority of species, dead wood item characteristics (especially tree species and whether standing or downed) were more important than measured stand characteristics and habitat connectivity. Whether the stands were clear-cuts, mature forests, or reserves affected some species, whereas the stand-level amount of dead wood per hectare was not important for any species. Habitat connectivity improved the occurrence models for about a half of the species, but there were both positive and negative relationships, and they were generally weak. Forest management should include creation and retention of a high diversity of dead wood to sustain habitat for all species. In a forest-dominated landscape, the spatial distribution of dead wood is of little importance for common saproxylic beetle species.

Intraspecific variations in dispersal ability of saproxylic beetles in fragmented forest patches.

The extrapolation of metapopulation concepts to saproxylic insects suggests that the occupancy of forest patches and the colonization of ephemeral deadwood substrates are driven by micro-evolutionary processes that are related to adaptive plasticity and intraspecific sex-dependent polymorphism of dispersal traits. We hypothesized that forest fragmentation could favor more mobile individuals within populations, but little empirical data have been published on the potentially sex-biased response of insect populations to habitat availability. We selected 88 fragmented woodlots in two European agricultural landscapes to cover different degrees of spatio-temporal fragmentation, from small, isolated and recently established woodlots to large, inter-connected ancient woodlots. In line with our hypothesis, the average wing loading (WL), used as a proxy for dispersal ability, for each of nine flight-dispersing saproxylic beetle species should be lower in recent, small, isolated woodlots than in ancient, large, inter-connected woodlots, respectively (i.e. ancient vs. recent, small vs. large, isolated vs. connected). Forest patch size did not significantly influence the average dispersal ability of beetle colonizers. However, WL of one-third of the tested species did significantly respond to forest ancientness or connectivity. Significant patterns were sex-biased, probably due to the contrasting role of males and females in species colonization dynamics. WL was lower in recent than in ancient forest plots for Melandrya barbata males, and it was lower in isolated than in connected woodlots for Tetratoma ancora and Phymatodes testaceus males. Contrary to expectations, we did not observe any decrease in polymorphism of dispersal abilities with decreasing woodlot size or increasing isolation. Our findings give support to the usefulness of gender consideration in insect conservation ecology studies.

Increasing temperature may compensate for lower amounts of dead wood in driving richness of saproxylic beetles

Global warming and land‐use change are expected to be additive threats to global diversity, to which insects contribute the highest proportion. Insects are strongly influenced by temperature but also require specific habitat resources, and thus interaction between the two factors is likely. We selected saproxylic beetles as a model group because their life cycle depends on dead wood, which is highly threatened by land use. We tested the extent to which higher temperatures compensate for the negative effects of low amounts of dead wood on saproxylic beetle species richness (Temperature–Dead wood compensation hypothesis) on both a macroclimate and a topoclimate scale (north‐ and south‐facing slopes). We analyzed 1404 flight‐interception trap catches across Europe to test for interaction effects of temperature and dead‐wood amount on species richness. To experimentally test our findings from the activity trap data, we additionally reared beetles from 80 bundles of dead wood initially exposed at high and low elevations. At the topoclimate scale, we analyzed trap catches and reared beetles from dead wood exposed in 20 forest stands on south‐facing and north‐facing slopes in one region. On the macroscale, both temperature and dead‐wood amount positively affected total and threatened species richness independently, but their interaction was significantly negative, indicating compensation. On both scales and irrespective of the method, species richness decreased with temperature decline. Our observation that increasing temperature compensates for lower amounts of dead wood has two important implications. First, managers of production forests should adapt their dead‐wood enrichment strategy to site‐specific temperature conditions. Second, an increase in temperature will compensate at least partially for poor habitat conditions in production forests. Such a perspective contrasts the general assumption of reinforcing impacts of global warming and habitat loss on biodiversity, but it is corroborated by recent range expansions of threatened beetle species.

Proportions of saproxylic beetle populations that utilise clear-cut stumps in a boreal landscape – Biodiversity implications for stump harvest

Many saproxylic insects (insects dependent on deadwood) are threatened because the amounts of suitable substrate, coarse woody debris (CWD), are low in managed forests. Harvesting clear-cut stumps for bioenergy will decrease these amounts further and may therefore contribute to loss of biodiversity. Earlier studies have demonstrated that many saproxylic beetle species utilise clear-cut stumps. However, the importance of stumps compared with other kinds of deadwood remains unknown. In particular, some species adapted to sun-exposed deadwood created by disturbances might, in managed forest landscapes, be dependent on stumps in clear-cuts. In the present study we quantify the proportions of landscape-wide populations of saproxylic beetles that are recruited from clear-cut stumps in a managed boreal forest landscape. The amount of bark on clear-cut stumps and population densities (beetles per m2 bark) were estimated for a 24,499ha landscape in Sweden. Our data were pooled with estimates from a similar study in the same landscape, including all other types of CWD and beetle densities. The clear-cut stumps were estimated to contribute 15.5% of total bark to CWD in the landscape. For spruce, clear-cut stumps contributed 37.9% of the total bark. Of 39 analysed beetle species, 13 were estimated to have more than 10% of their populations in clear-cut stumps, 9 more than 50%, and 5 more than 80%. Clear-Cut stumps are thus an important breeding substrate for many beetle species and consequently, intensive stump harvest risks decreasing biodiversity.

Numerical responses of saproxylic beetles to rapid increases in dead wood availability following geometrid moth outbreaks in sub-arctic mountain birch forest.

Saproxylic insects play an important part in decomposing dead wood in healthy forest ecosystems, but little is known about their role in the aftermath of large-scale forest mortality caused by pest insect outbreaks. We used window traps to study short-term changes in the abundance and community structure of saproxylic beetles following extensive mortality of mountain birch in sub-arctic northern Norway caused by an outbreak of geometrid moths. Three to five years after the outbreak, the proportion of obligate saproxylic individuals in the beetle community was roughly 10% higher in forest damaged by the outbreak than in undamaged forest. This was mainly due to two early-successional saproxylic beetle species. Facultative saproxylic beetles showed no consistent differences between damaged and undamaged forest. These findings would suggest a weak numerical response of the saproxylic beetle community to the dead wood left by the outbreak. We suggest that species-specific preferences for certain wood decay stages may limit the number of saproxylic species that respond numerically to an outbreak at a particular time, and that increases in responding species may be constrained by limitations to the amount of dead wood that can be exploited within a given timeframe (i.e. satiation effects). Low diversity of beetle species or slow development of larvae in our cold sub-arctic study region may also limit numerical responses. Our study suggests that saproxylic beetles, owing to weak numerical responses, may so far have played a minor role in decomposing the vast quantities of dead wood left by the moth outbreak.

Low host‐tree preferences among saproxylic beetles: a comparison of four deciduous species

AbstractMany wood‐dwelling beetles rely on old hollow trees. In Europe, oaks are known to harbour a species‐rich saproxylic beetle fauna, while less is known regarding other broad‐leaved tree species. Furthermore, the extent to which saproxylic insect species have specialised on different tree species remains unknown.In this study, we sampled beetles through pitfall traps and window traps in four different tree species in a landscape with many old oaks.We recorded 242 saproxylic beetle species of which 27 were red‐listed. After eliminating the species recorded only on a single tree, few cases among the 171 remaining species in the data set were confined to a single tree species.Using odds ratios, we showed that 19 of the 171 beetle species showed significant associations withQuercus roburin at least one of the two trap types. ForAcer platanoides, Fraxinus excelsiorandTilia cordata, the corresponding numbers were 6, 2 and 5, respectively. One species showed a negative association withQ. robur.Using meta‐analysis, we quantified the degree of association between the beetle species and the tree species. The associations were most profound among species classified as obligate saproxylic rather than facultative in lifestyle. Overall, a significant association was only found withQ. robur.We conclude that the saproxylic fauna is dominated by non‐specialist species but includes a small proportion of truly host‐tree‐specific species. Furthermore, other broad‐leaved trees can be important as supporting habitats for many saproxylic organisms that have had presumed associations with oaks to date.

Fast but ephemeral effects of ecological restoration on forest beetle community

Many protected areas have a long history of human intervention before being protected. In protected forests, the past land use has reduced the amount of natural structures, which are crucial substrates for thousands of species. We evaluate the short-term ecological effect of forest restoration (dead wood creation) on conifer-associated saproxylic (dead-wood dependent) beetles. More specifically, we analyze the effect of dead wood creation on the number of beetle species and individuals 1 and 5 years after restoration in spruce and pine forests, using a large-scale monitoring network over Finland. The number of saproxylic beetle species and individuals was larger at restored than at control plots both 1 and 5 years after restoration in both spruce and pine forests. Community composition in restored plots was different from control plots 1 year after restoration, but had returned towards the control plot composition 5 years after restoration, while control plots remained largely unchanged. Both in spruce and pine forests, there were more red-listed and rare saproxylic beetles in restored than in control plots 1 and 5 years after restoration. Our results indicate that restoration has an overall positive influence on saproxylic beetle diversity immediately after dead wood creation, but this effect is rather short-lived. Long term monitoring of restored dead wood is crucial in investigating successional pathways as well as biotic communities in advanced decay stages, and in fully evaluating the ecological effect of dead wood creation as a forest restoration measure.

High-accuracy sampling of saproxylic diversity indicators at regional scales with pheromones: The case of Elater ferrugineus (Coleoptera, Elateridae)

The rare beetle Elater ferrugineus was sampled at 47 sites in the county of Östergötland, Sweden by means of pheromone-baited traps to assess its value as an indicator species for hollow oak stands rich in rare saproxylic beetle species. In addition, Osmoderma eremita was also sampled with pheromone baits. These data were then compared against species survey data collected at the same sites by pitfall and window traps. Both species co-occur with many Red Listed saproxylic beetles, with E. ferrugineus being a somewhat better indicator for the rarest species. The conservation value of a site (measured as Red List points or number of Red Listed species) increased with the number of specimens of E. ferrugineus and O. eremita caught. Accuracy of sampling by means of pheromone trapping turned out to be radically different for the two model species. E. ferrugineus traps put out during July obtained full accuracy after only 6days, whereas O. eremita traps needed to be out from early July to mid-August in order to obtain full accuracy with one trap per site. By using E. ferrugineus, or preferably both species, as indicator species, accuracy would increase and costs decrease for saproxylic biodiversity sampling, monitoring and identification of hotspots.

A review of Turkish saproxylic beetles from the European Red List

SummaryThe conservation of beetles that depend on dying or dead wood (i.e. saproxylic), has received a great deal of attention in many parts of the world in recent years. Human activities such as urbanization and logging, and their results, e.g. global warming, destroy natural ecosystems and threaten unusual species such as Lucanus cervus (L. 1758), Rosalia alpina (L. 1758), Limoniscus violaceus (Müller 1821) and Osmoderma eremita (Scopoli 1763). Attempts have been made to conserve the habitats upon which these species depend. Although represented by a large number of species, saproxylic beetles in Turkey have not received much attention. Although some Turkish studies have acknowledged their value, comprehensive investigations of these species are very limited. The aim of this study is to make a list, from the literature, of the species that are endangered in Europe and found in Turkey, to highlight the importance of these species. The research includes 151 saproxylic beetle species belonging to the families Bostrichidae, Cerambycidae, Elateridae, Eucnemidae, Scarabaeidae, Euchiridae, Lucanidae and Mycetophagidae. The list of Turkish saproxylic beetles was prepared using the European Red List of Saproxylic Beetles. Information is provided about the IUCN Red List category in Europe, the locations of the species in Turkey, and their global geographic range. We gathered all data about these species from the international literature. Furthermore, we also include in the list certain species whose locations are not specified, but which inhabit Turkey. We obtained their records from some catalogs in Turkey. In addition to the list, we prepared three distribution maps for Turkey. The maps show distribution in Turkey of some species in the Endangered, Vulnerable and Near Threatened categories in the European Red List. It is expected that this study will lead to comprehensive studies on saproxylic beetles from Turkey.

Some of the rarest European saproxylic beetles are common in the wilderness of Northern Mongolia

Natural landscapes characterized by heavy disturbance regimes were displaced in Europe by managed cultural landscapes over the past centuries. The associated loss of biological legacies, such as dead or dying trees, has exposed numerous saproxylic species to high risks of extinction. In contrast, extensive wilderness forests in Northern Mongolia have been sustained owing to significant cultural differences. Here we used saproxylic beetle abundance data gathered during two sampling campaigns in the Mongolian taiga to address whether (1) the saproxylic beetle fauna of the Mongolian taiga is comparable to that of European boreal forests, (2) fires are a natural disturbance regime, indicated by the occurrence of many pyrophilous species, and (3) species rare in Europe are also rare in the Northern Mongolian wilderness. Of 191 saproxylic beetle species identified, 150 (79 %) were also found in Europe. The high number of pyrophilous beetle species (20) indicated that natural species communities are well adapted to this disturbance regime. The species rarity in Germany was significantly positively correlated with the species rarity in Finland, but the species rarity in these two countries was negatively correlated with that in the Mongolian wilderness. Our results indicated that wilderness areas with natural disturbances provide biological legacies important for rare species. Therefore, exploitation of the unique, remaining natural landscapes of the Palaearctic wilderness areas should be stopped. Moreover, we urge conservationists to expand controlled burning for restoration at relict sites of rare boreal species also outside Fennoscandia.

Wood-inhabiting beetles (Coleoptera) associated with oaks in a global biodiversity hotspot: a case study and checklist for Israel

The East Mediterranean region is a global biodiversity hotspot for vertebrates and plants. Although oaks (Quercus) are the dominant tree species in semi-natural Mediterranean forests, the insect species richness associated with East Mediterranean oak forest has been insufficiently studied. Species richness and composition of the saproxylic beetle assemblage, including its seasonal variation, of a stand of old oaks (Quercus calliprinos) in northern Israel was investigated. Flight-interception traps were used to sample beetles over a period of 2 years. In addition, a set of pitfall traps was placed in the trunk hollows in the second year of the study. Fifty-two saproxylic beetle species were found associated with oaks in the field study. Among them, two saproxylic click-beetle species were previously unknown to science, and eight species represent new records for Israel. Both the number of species and the number of individuals showed two distinct phenological peaks during the year. A preliminary list of saproxylic beetles inhabiting oaks in Israel was prepared and biogeographical distribution, host plants, habitat guild, and activity period are presented for each species. Together with our own data, the literature survey conducted for 19 beetle families established that at least 124 saproxylic beetle species are associated with oaks in Israel while about 40% of them are unique to the Levantine region. As most localities with old-growth oak forest structures are small and isolated, ongoing management should have high priority despite the fact that these forests already receive protection.