Priority areas for the conservation of subtropical indigenous forest in southern Africa: a case study from KwaZulu-Natal

Southern Africa's subtropical forest biome, though small and highly fragmented, supports much of the region's biodiversity. With limited resources available for conservation and the exploitative use of forest escalating, identifying a network of priority forest reserves is important. We examine the distribution of forest birds, butterflies and mammals in KwaZulu-Natal, South Africa. Using an iterative algorithm we explore the efficiency of existing protected areas, species richness and rarity hotspots, prime forest sites (selected by forest area) and complementary networks as alternative approaches to priority reserve selection, as well as the potential use of indicator taxa. Existing protected areas represent 98% of species but are relatively inefficient in terms of area. Alternative selection criteria represent a high proportion of species (86–92%) and provide efficient bases for developing fully representative reserve networks. All species are represented within a network of 22 complementary quarter degree cells. This network includes several larger forests and existing protected areas and is recommended for priority conservation. Complementary networks identified separately for birds, butterflies and mammals overlap little, but each represents a high proportion of the remaining taxa, supporting their potential as representative 'indicator' taxa. The evolutionary history of the three main forest types in KwaZulu-Natal explains observed spatial patterns of alternative reserve networks. Priority areas are concentrated in scarp and coastal forest belts, regions of comparatively recent evolutionary activity with high species richness. Afromontane forest is older and less diverse, but its inclusion in any reserve network is necessary for the full representation of forest diversity.     

Distribution and conservation status of forest bamboo biodiversity in the Asia-Pacific Region

Although Asian bamboo species constitute a non-timber forest product of major cultural and economic importance, no detailed regional assessment of their distribution patterns has previously been made. To assess the potential of the existing bamboo species distribution data for production of regional mapping tools for planning the conservation of forest-based biodiversity, data on bamboo distribution and forest cover were combined. Over 1000 bamboo species from 60 genera of woody bamboos were incorporated, allowing the mapping of individual species or groups of species and genera, along with potential species richness and biodiversity hotspots. Over 6.3 million km² of Asian forest potentially contains bamboo, with highest densities indicated from northeastern India through Burma to southern China, and through Sumatra to Borneo. The highest figures for potential species richness (144 spp per square km) were recorded in forests of south China, including Hainan Island. Despite substantial inadequacies and inconsistencies in knowledge of the taxonomy and distribution of bamboo species, this approach may provide a valuable tool for planning in situ conservation of forest biodiversity.     

The high value of logged tropical forests: lessons from northern Borneo

The carbon storage and conservation value of old-growth tropical forests is clear, but the value of logged forest is less certain. Here we analyse >100,000 observations of individuals from 11 taxonomic groups and >2,500 species, covering up to 19?years of post-logging regeneration, and quantify the impacts of logging on carbon storage and biodiversity within lowland dipterocarp forests of Sabah, Borneo. We estimate that forests lost ca. 53% of above-ground biomass as a result of logging but despite this high level of degradation, logged forest retained considerable conservation value: floral species richness was higher in logged forest than in primary forest and whilst faunal species richness was typically lower in logged forest, in most cases the difference between habitats was no greater than ca. 10%. Moreover, in most studies >90% of species recorded in primary forest were also present in logged forest, including species of conservation concern. During recovery, logged forest accumulated carbon at five times the rate of natural forest (1.4 and 0.28?Mg?C?ha^?1?year^?1, respectively). We conclude that allowing the continued regeneration of extensive areas of Borneo??s forest that have already been logged, and are at risk of conversion to other land uses, would provide a significant carbon store that is likely to increase over time. Protecting intact forest is critical for biodiversity conservation and climate change mitigation, but the contribution of logged forest to these twin goals should not be overlooked.     

Four Decades of Forest Persistence,Clearance and Logging on Borneo

The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km²) of Borneo''s area (737,188 km²) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km² (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km², representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km⁻², and the lowest density in Brunei, at 0.18 km km⁻². Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km² of 1973 forest cover has been logged. With 389,566 km² (52.8%) of the island remaining forested, of which 209,649 km² remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.     

Diversity and endemism of woody plant species in the Equatorial Pacific seasonally dry forests

The biodiversity hotspot of the Equatorial Pacific region in western Ecuador and northwestern Peru comprises the most extensive seasonally dry forest formations west of the Andes. Based on a recently assembled checklist of the woody plants occurring in this region, we analysed their geographical and altitudinal distribution patterns. The montane seasonally dry forest region (at an altitude between 1,000 and 1,100 m, and the smallest in terms of area) was outstanding in terms of total species richness and number of endemics. The extensive seasonally dry forest formations in the Ecuadorean and Peruvian lowlands and hills (i.e., forests below 500 m altitude) were comparatively much more species poor. It is remarkable though, that there were so many fewer collections in the Peruvian departments and Ecuadorean provinces with substantial mountainous areas, such as Cajamarca and Loja, respectively, indicating that these places have a potentially higher number of species. We estimate that some form of protected area (at country, state or private level) is currently conserving only 5% of the approximately 55,000 km² of remaining SDF in the region, and many of these areas protect vegetation at altitudes below 500 m altitude. In contrast, the more diverse seasonally dry forests in mountainous areas remain little protected.     

Spillover of Insects from Rain Forest into Adjacent Oil Palm Plantations

Conversion of natural forest to oil palm plantations is a major threat to biodiversity in Southeast Asia. The retention of natural forest habitats within plantations has been proposed as a method to reduce biodiversity losses in agricultural areas, and we examined whether forest areas resulted in spillover of species into adjacent oil palm plantations. We sampled ants and butterflies along two 2‐km transects across an ecotone from plantation into adjacent forest in Sabah, Malaysian Borneo. Species richness of both taxa was reduced in plantations, but to a greater extent in butterflies (54% reduction) than in ants (25% reduction). Butterfly diversity increased in plantations with increasing proximity to forest primarily due to spillover of ‘vagrant’ forest species (whose larval host plants do not occur in plantations), although richness of species that could potentially breed in plantations also increased near to forest. By contrast, ants showed no spillover effects and were less sensitive to land‐use changes, with much higher levels of similarity in species assemblages across habitats than for butterflies. Our results for butterflies suggest that despite the negative impacts of plantations on diversity, proximity to forest could improve diversity in adjacent plantations for some taxa. Spillover of forest species implies that retaining forest areas within plantations may be important for facilitating dispersal of some species through the landscape.     

The effectiveness of a Mesoamerican ‘paper park’ in conserving cloud forest avifauna

Mesoamerican cloud forests are important centres of biodiversity, but are under severe pressure from anthropogenic activities. Protected areas have been established to conserve remaining areas of this habitat, but it is debatable how effective these under-resourced ‘paper parks’ are in preserving biodiversity. This study investigates this issue utilising species-level data, examining composition of avifaunal communities within an undermanaged cloud forest park. Research was conducted in the Parque Nacional Cusuco, North–West Honduras. Results indicate that overall avian species richness is greater in the less heavily protected buffer zone than the nominally inviolate core zone. However, core zone areas are shown to be effective in preserving threatened and range-restricted species. Results therefore demonstrate that buffer zone forest has a comparably reduced conservation value, but the overall park system appears to be effective in conserving the core zone. These findings should be taken into account when considering extensions to protected area networks in Mesoamerica.     

Burning and logging differentially affect endemic vs. widely distributed butterfly species in Borneo

We assess the differential impact of logging and ENSO (El Niño Southern Oscillation)-induced disturbance on the relative butterfly abundance and species richness of range-restricted and widespread species within the island of Borneo. Relative abundance and species richness were assessed using rarefaction and species accumulation curves in unburned isolates surrounded by burned forest, the burned forest itself, and continuous forest unaffected by ENSO-induced disturbance in addition to logged and unlogged landscapes in unburned forest. The relative abundance of endemics was significantly higher in unlogged forest than logged forest and significantly higher in unburned forest than burned forest. Rarefied species richness of range categories was similar (Bornean endemics) or higher (other categories) in selectively logged than unlogged forest. In contrast, rarefied species richness of range-restricted species was highest in continuous forest, intermediate in unburned isolates, and lowest in burned forest. Only two individuals of a single Bornean endemic species were found in all the burned forest. Although species richness was higher in all range categories in continuous forest than in unburned isolates and in burned forest, the difference was most pronounced for range-restricted species. Logging and ENSO-induced fires thus have contrasting effects on range-restricted species. While both increase the relative abundance of widely distributed species at the expense of range-restricted species, only ENSO-induced disturbance lowers the rarefied number of restricted range species. Our research highlights the threat that severe ENSO events pose to geographically restricted classes of biodiversity.     

Do riparian reserves support dung beetle biodiversity and ecosystem services in oil palm-dominated tropical landscapes?

Agricultural expansion and intensification are major threats to global biodiversity, ecological functions, and ecosystem services. The rapid expansion of oil palm in forested tropical landscapes is of particular concern given their high biodiversity. Identifying management approaches that maintain native species and associated ecological processes within oil palm plantations is therefore a priority. Riparian reserves are strips of forest retained alongside rivers in cultivated areas, primarily for their positive hydrological impact. However, they can also support a range of forest‐dependent species or ecosystem services. We surveyed communities of dung beetles and measured dung removal activity in an oil palm‐dominated landscape in Sabah, Malaysian Borneo. The species richness, diversity, and functional group richness of dung beetles in riparian reserves were significantly higher than in oil palm, but lower than in adjacent logged forests. The community composition of the riparian reserves was more similar to logged forest than oil palm. Despite the pronounced differences in biodiversity, we did not find significant differences in dung removal rates among land uses. We also found no evidence that riparian reserves enhance dung removal rates within surrounding oil palm. These results contrast previous studies showing positive relationships between dung beetle species richness and dung removal in tropical forests. We found weak but significant positive relationships between riparian reserve width and dung beetle diversity, and between reserve vegetation complexity and dung beetle abundance, suggesting that these features may increase the conservation value of riparian reserves. Synthesis and applications: The similarity between riparian reserves and logged forest demonstrates that retaining riparian reserves increases biodiversity within oil palm landscapes. However, the lack of correlation between dung beetle community characteristics and dung removal highlights the need for further research into spatial variation in biodiversity–ecosystem function relationships and how the results of such studies are affected by methodological choices.     

The Influence of Habitat,Season, and Detectability on Abundance Estimates across an Amazonian Parrot Assemblage

The Amazon basin holds very high parrot species richness but almost nothing is known of parrot population densities in the region or how these vary between species, habitats, sites, and seasons. Such data are becoming important as humans impact on increasing areas of the region. Seventeen parrot species were surveyed using a line transect distance sampling method over 3 yr in floodplain and terra firme forests at two sites in the Tambopata region of southeast Peru. Density estimates for most species were in the range of 3.3–7.8/km², with Brotogeris cyanoptera and Amazona farinosa reaching densities of 22 and 23/km² in floodplain forest during the dry season. Parrot densities were higher in floodplain forest than in terra firme forest at both sites. The parrot communities of terra firme forests were similar across sites and seasons, but those in floodplain forests differed widely across sites and across seasons. Upper canopy birds are notoriously difficult to survey. We introduce a procedure to correct for the likely violation of the assumption that all birds on the transect line are detected (distance sampling assumption g(0) = 1). We correct g(0) based on calling rates of birds using a cue‐counting technique. Multipliers for g(0) differ across species and site, but not season. This method yielded density estimates on average 22 percent higher (6–40% higher in individual species) than those from the standard method.     

Fuelling the biodiversity crisis: species loss of ground-dwelling forest ants in oil palm plantations in Sabah,Malaysia (Borneo)

Oil palm plantations today cover large areas of former tropical lowland rain forest in Southeast Asia and are rapidly expanding on the island of Borneo. Study of the community of ground-dwelling ants in different plantations in Sabah, Malaysia, over 2 years using tuna baiting, revealed that the oil palm plantation ground ant community was severely reduced in species richness in comparison to the forest interior, regardless of age, undergrowth cover, or proximity to neighbouring forest. The results indicate that oil palm plantation habitats, now covering more than 15% of Sabah’s land area, can sustain only about 5% of the ground-dwelling ant species of the forest interior. Nine of the 23 ant species baited in the plantations were never recorded inside forest. All numerically dominant ants were non-forest species. The most common species was Anoplolepis gracilipes, an invasive species present at 70% of all bait sites and known to cause ‘ecological meltdowns’ in other situations. The low frequency and species number of forest ground ants indicates that oil palm plantations act as effective dispersal barriers leading to community isolation in rain forest remnants. The replacement of natural forests with oil palm plantations poses a serious threat to the conservation of biodiversity on Borneo if similar results are confirmed in other taxa.     

Recovery of indigenous butterfly community following control of invasive alien plants in a tropical island’s wet forests

Invasive alien species pose one of the highest threats to biodiversity, especially in isolated oceanic islands where high rates of both endemism and extinction risk also usually prevail. Few studies have investigated the impact of invasive alien plants on butterflies in insular ecosystems, despite butterflies representing a key indicator group for terrestrial arthropod diversity. Using the Pollard Technique, we quantified butterfly species richness and abundance in eight wet lowland forest areas invaded by alien plants, principally the strawberry guava (Psidium cattleianum Sabine) on the tropical volcanic island of Mauritius, and compared the results with paired adjacent forest plots that had been weeded of alien plants between 2 and 12 years previously. Butterfly assemblages in weed-infested and weeded forests were distinctly different with higher species richness and much higher butterfly abundance in the latter. At least some of these differences seemed attributable to weed removal effects on forest structure, but understanding the precise mechanisms involved will require further study. The results suggest that alien plant invasion may have contributed to the extinction of certain endemic taxa and can increase the likelihood of butterfly species extinction by reducing population sizes through reduced habitat quality. Such a shift in a forest’s butterfly assemblage is likely to have negative effects on both their indigenous predators and the plants they pollinate. It is argued that in order to maintain butterfly and other arthropod diversity and function in these forests, alien plant control must be maintained and extended beyond the current 1% of surviving forest remnants.     

Importance of semi-natural habitats for the conservation of butterfly communities in landscapes dominated by pine plantations

While the area of plantation forests continues to increase worldwide, their contribution to the conservation of biodiversity is still controversial. There is a particular concern on the central role played by natural habitat remnants embedded within the plantation matrix in conserving species-rich insect communities. We surveyed butterflies in maritime pine plantation landscapes in south-western France in 83 plots belonging to seven habitat types (five successional stages of pine stands, native deciduous woodlands and herbaceous firebreaks). The effect of plot, habitat and landscape attributes on butterfly species richness, community composition and individual species were analysed with a General Linear Model (GLM), partial Canonical Correspondence Analysis (CCA) and the IndVal method. The most important factors determining butterfly diversity and community composition were the presence of semi-natural habitats (deciduous woodlands and firebreaks) at the landscape scale and the composition of understorey vegetation at the plot scale. Pure effects of plot variables explained the largest part of community variation (12.8%), but landscape factors explained an additional, independent part (6.7%). Firebreaks were characterized by a higher species richness and both firebreaks and deciduous woodlands harboured species not or rarely found in pine stands. Despite the forest-dominated landscape, typical forest butterflies were rare and mainly found in the deciduous woodlands. Threatened species, such as Coenonympha oedippus and Euphydryas aurinia, were found in pine stands and in firebreaks, but were more abundant in the latter. In the studied plantation forest, the conservation of butterflies depends mainly on the preservation of semi-natural habitats, an adequate understorey management and the maintenance of soil moisture levels.     

A global overview of the conservation status of tropical dry forests

Aim To analyse the conservation status of tropical dry forests at the global scale, by combining a newly developed global distribution map with spatial data describing different threats, and to identify the relative exposure of different forest areas to such threats. Location Global assessment. Methods We present a new global distribution map of tropical dry forest derived from the recently developed MODIS Vegetation Continuous Fields (VCF) product, which depicts percentage tree cover at a resolution of 500 m, combined with previously defined maps of biomes. This distribution map was overlaid with spatial data to estimate the exposure of tropical dry forests to a number of different threats: climate change, habitat fragmentation, fire, human population density and conversion to cropland. The extent of tropical dry forest currently protected was estimated by overlaying the forest map with a global data set of the distribution of protected areas. Results It is estimated that 1,048,700 km² of tropical dry forest remains, distributed throughout the three tropical regions. More than half of the forest area (54.2%) is located within South America, the remaining area being almost equally divided between North and Central America, Africa and Eurasia, with a relatively small proportion (3.8%) occurring within Australasia and Southeast Asia. Overall, c. 97% of the remaining area of tropical dry forest is at risk from one or more of the threats considered, with highest percentages recorded for Eurasia. The relative exposure to different threats differed between regions: while climate change is relatively significant in the Americas, habitat fragmentation and fire affect a higher proportion of African forests, whereas agricultural conversion and human population density are most influential in Eurasia. Evidence suggests that c. 300,000 km² of tropical dry forest now coincide with some form of protected area, with 71.8% of this total being located within South America. Main conclusions Virtually all of the tropical dry forests that remain are currently exposed to a variety of different threats, largely resulting from human activity. Taking their high biodiversity value into consideration, this indicates that tropical dry forests should be accorded high conservation priority. The results presented here could be used to identify which forest areas should be accorded highest priority for conservation action. In particular, the expansion of the global protected area network, particularly in Mesoamerica, should be given urgent consideration.     

How can we preserve and restore species richness of pollinating insects on agricultural land?

During recent decades, concern about the loss of biodiversity on agricultural land has increased, and semi‐natural grasslands have been highlighted as critical habitats. Temperate European agricultural landscapes require distinct and appropriate management to prevent further impoverishment of the flora and fauna. This is especially urgent for pollinating insects that provide important ecosystem services. Our aim was to examine how species richness of three important groups of pollinating insects; solitary bees, butterflies and burnet moths are related to different farm characteristics, and if there are any differences between these three groups. A further aim was to test if red‐listed species are related to any farm characteristics. Species richness of solitary bees, butterflies and burnets was measured on all semi‐natural grasslands at 16 farms in a forest‐dominated area of 50 km² in southern Sweden, using systematic transect walks in April to September 2003 (only butterflies and burnets) and 2005. Species richness of solitary bees and butterflies was intercorrelated, both before and after controlling for the area of semi‐natural grassland. Species richness of solitary bees increased with the area of semi‐natural grassland. After controlling for the effect of the area of semi‐natural grassland species richness was strongly positively related with the density of the plant Knautia arvensis and negatively related with the proportion of grazed grassland. The results were similar for solitary bees and butterflies. The number of red‐listed solitary bees was positively related to the proportion of meadows with late harvest (after mid‐July) and decreased with increased farm isolation. The number of burnet species (all red‐listed) was positively related to vegetation height, flower density and the proportion of meadows with late harvest on a farm. Areas with a high density of K. arvensis and with traditional hay‐meadow with late harvest present, harbour most species. Promoting traditional hay‐meadows, late extensive grazing and the herb K. arvensis, people managing agricultural biodiversity can encompass high species richness of pollinating insects and support red‐listed species. Further, we suggest that the density of K. arvensis at a farm can be used as a biodiversity indicator, at least for pollinating insects.     

Diversity and composition of fruit-feeding butterflies in tropical <Emphasis Type="Italic">Eucalyptus</Emphasis> plantations

Production landscapes are rarely considered as priority areas for biodiversity conservation in the tropics. Tree plantations have the potential to provide a conservation service in much of the humid tropics since they are rapidly increasing in extent and present less of a structural contrast with native vegetation than many more intensive agricultural land-uses. We used hierarchical partitioning to examine the factors that influence the value of large-scale Eucalyptus plantations for tropical fruit-feeding butterflies (Lepidoptera: Nymphalidae) in the Brazilian Amazon. We focused on evaluating the importance of landscape versus stand-level factors in determining the diversity and composition of butterfly assemblages, and how butterfly-environment relationships vary within and between subfamilies of Nymphalidae. Native understorey vegetation richness had the strongest independent effect on the richness, abundance and composition of all fruit-feeding butterflies, as well as a subset of species that had been recorded in nearby primary forests. However, overall patterns were strongly influenced by the most abundant subfamily (Satyrinae), and vegetation richness was not related to the abundance of any other subfamily, or non-Satyrinae species, highlighting the importance of disaggregating the fruit-feeding Nymphalidae when examining butterfly-environment relationships. Our results suggest that plantations can help conserve a limited number of forest species, and serve to highlight the research that is necessary to understand better the relationship between fruit-feeding butterflies and environmental variables that are amenable to management.     

Kitam Bird Sanctuary,the only low elevation protected area of Sikkim: A conservation hotspot for butterflies in the Eastern Himalaya

The lowland areas of the Himalayan region are subjected to immense anthropogenic pressure because of least representation in the protected area network. Kitam Bird Sanctuary is the only representative protected area that occurs below 1000 m in Sikkim state of India (a part of globally significant biodiversity hotspot of Himalayas) and serves as the refuge for various species of flora and fauna. Here we studied butterfly diversity and community composition in Kitam Bird Sanctuary (a small protected area of 6 km² geographical area) following point count method spread across predetermined transects. Altogether 1674 butterflies belonging to 111 species and six families were recorded after completion of 240 point counts. Among these, 18 species are federally protected under the Wildlife (Protection) Act (1972) of India. Most of the butterflies were forest specialist in terms of habitat preference, whereas based on host plant specificity, the butterfly community was mostly dominated by generalist feeder (Oligophagous II and Polyphagous). Butterfly community parameters showed a strong correlation with habitat variables. While Kitam Bird Sanctuary is primarily designated for conservation of lowland birds, the high diversity of butterflies both in terms of taxonomic richness and trait composition suggests that the sanctuary harbors an ideal habitat for butterflies of the tropical region and invites conservation attention.     

Richness of Lichen Species,Especially of Threatened Ones,Is Promoted by Management Methods Furthering Stand Continuity

Lichens are a key component of forest biodiversity. However, a comprehensive study analyzing lichen species richness in relation to several management types, extending over different regions and forest stages and including information on site conditions is missing for temperate European forests. In three German regions (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin), the so-called Biodiversity Exploratories, we studied lichen species richness in 631 forest plots of 400 m² comprising different management types (unmanaged, selection cutting, deciduous and coniferous age-class forests resulting from clear cutting or shelterwood logging), various stand ages, and site conditions, typical for large parts of temperate Europe. We analyzed how lichen species richness responds to management and habitat variables (standing biomass, cover of deadwood, cover of rocks). We found strong regional differences with highest lichen species richness in the Schwäbische Alb, probably driven by regional differences in former air pollution, and in precipitation and habitat variables. Overall, unmanaged forests harbored 22% more threatened lichen species than managed age-class forests. In general, total, corticolous, and threatened lichen species richness did not differ among management types of deciduous forests. However, in the Schwäbische-Alb region, deciduous forests had 61% more lichen species than coniferous forests and they had 279% more threatened and 76% more corticolous lichen species. Old deciduous age classes were richer in corticolous lichen species than young ones, while old coniferous age-classes were poorer than young ones. Overall, our findings highlight the importance of stand continuity for conservation. To increase total and threatened lichen species richness we suggest (1) conserving unmanaged forests, (2) promoting silvicultural methods assuring stand continuity, (3) conserving old trees in managed forests, (4) promoting stands of native deciduous tree species instead of coniferous plantations, and (5) increasing the amount of deadwood in forests.     

The conservation value of South East Asia's highly degraded forests: evidence from leaf-litter ants

South East Asia is widely regarded as a centre of threatened biodiversity owing to extensive logging and forest conversion to agriculture. In particular, forests degraded by repeated rounds of intensive logging are viewed as having little conservation value and are afforded meagre protection from conversion to oil palm. Here, we determine the biological value of such heavily degraded forests by comparing leaf-litter ant communities in unlogged (natural) and twice-logged forests in Sabah, Borneo. We accounted for impacts of logging on habitat heterogeneity by comparing species richness and composition at four nested spatial scales, and examining how species richness was partitioned across the landscape in each habitat. We found that twice-logged forest had fewer species occurrences, lower species richness at small spatial scales and altered species composition compared with natural forests. However, over 80 per cent of species found in unlogged forest were detected within twice-logged forest. Moreover, greater species turnover among sites in twice-logged forest resulted in identical species richness between habitats at the largest spatial scale. While two intensive logging cycles have negative impacts on ant communities, these degraded forests clearly provide important habitat for numerous species and preventing their conversion to oil palm and other crops should be a conservation priority.     

The white-backed woodpecker: umbrella species for forest conservation planning?

In northern Europe, a long history of land use has led to profound changes within forest ecosystems. The white-backed woodpecker (Dendrocopos leucotos) is one of several specialised forest species whose populations have declined. Conservation management directed at this species’ habitat has made it a de facto umbrella species for conservation of the biodiversity associated with forests rich in deciduous trees and dead wood. We assessed empirically the value of the white-backed woodpecker as an indicator and umbrella species in central Sweden. Occurrence of the woodpecker in breeding bird atlas squares (5 × 5 km²) indicated high species richness of forest birds, particularly species of special conservation concern, which included on average 13% more species in squares with than without the woodpecker. The number of red-listed cryptogam species expected to benefit from conservation actions directed at white-backed woodpecker habitats was higher in squares where the woodpecker bred compared to where is was absent. However, no such pattern was found for red-listed beetles, a group with very few records in the studied squares. White-backed woodpecker occurrence was positively associated with the current area of deciduous and mixed forest of high conservation value. Considering its indicator value, its specialised habitat requirements and its potential as a communication tool, using the white-backed woodpecker as an umbrella species may provide a coarse filter for the conservation of several other deciduous forest species. However, focusing solely on white-backed woodpecker habitat may not provide for the conservation of all such species, which stresses the need for a suite of complementary planning approaches.