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Birds constitute one of the most important seed dispersal agents globally, especially in the tropics. The feeding preferences of frugivorous birds are, therefore, potentially of great ecological importance. A number of laboratory‐based and observational studies have attempted to ascertain the preferences of certain bird species for certain fruit traits. However, little attention has been paid to community‐wide preferences of frugivorous birds and the impact this may have on fruit traits on a broader scale. Here, we used artificial fruits of different colors and sizes to investigate community‐wide fruit trait preferences of birds at three sites along an elevational gradient in Papua New Guinea. We recorded attack rates on artificial fruits as visible impressions made by a bird's beak during a feeding attempt. We also measured the colors and sizes of real fruits at each site, and the gape widths of frugivorous birds, allowing for comparisons between bird feeding preferences and bird and fruit traits. Regardless of elevation, red and purple fruits were universally preferred to green and attacked at similar rates to one another, despite strong elevational patterns in real fruit color. However, elevation had a significant effect on fruit size preferences. A weak, non‐significant preference for large fruits was recorded at 700 m, while medium fruits were strongly preferred at 1700 m and small fruits at 2700 m. These patterns mirror those of both real fruit size and frugivorous bird gape width along the gradient, suggesting the potential for selective pressure of birds on fruit size at different elevations. [ABSTRACT FROM AUTHOR]

Large‐scale reforestation can potentially bring both benefits and risks to the water cycle, which needs to be better quantified under future climates to inform reforestation decisions. We identified 477 water‐insecure basins worldwide accounting for 44.6% (380.2 Mha) of the global reforestation potential. As many of these basins are in the Asia‐Pacific, we used regional coupled land‐climate modeling for the period 2041–2070 to reveal that reforestation increases evapotranspiration and precipitation for most water‐insecure regions over the Asia‐Pacific. This resulted in a statistically significant increase in water yield (p <.05) for the Loess Plateau–North China Plain, Yangtze Plain, Southeast China, and Irrawaddy regions. Precipitation feedback was influenced by the degree of initial moisture limitation affecting soil moisture response and thus evapotranspiration, as well as precipitation advection from other reforested regions and moisture transport away from the local region. Reforestation also reduces the probability of extremely dry months in most of the water‐insecure regions. However, some regions experience nonsignificant declines in net water yield due to heightened evapotranspiration outstripping increases in precipitation, or declines in soil moisture and advected precipitation. [ABSTRACT FROM AUTHOR]

When searching for food, great tits (Parus major) can use herbivore‐induced plant volatiles (HIPVs) as an indicator of arthropod presence. Their ability to detect HIPVs was shown to be learned, and not innate, yet the flexibility and generalization of learning remain unclear.We studied if, and if so how, naïve and trained great tits (Parus major) discriminate between herbivore‐induced and noninduced saplings of Scotch elm (Ulmus glabra) and cattley guava (Psidium cattleyanum). We chemically analyzed the used plants and showed that their HIPVs differed significantly and overlapped only in a few compounds.Birds trained to discriminate between herbivore‐induced and noninduced saplings preferred the herbivore‐induced saplings of the plant species they were trained to. Naïve birds did not show any preferences. Our results indicate that the attraction of great tits to herbivore‐induced plants is not innate, rather it is a skill that can be acquired through learning, one tree species at a time.We demonstrate that the ability to learn to associate HIPVs with food reward is flexible, expressed to both tested plant species, even if the plant species has not coevolved with the bird species (i.e., guava). Our results imply that the birds are not capable of generalizing HIPVs among tree species but suggest that they either learn to detect individual compounds or associate whole bouquets with food rewards. [ABSTRACT FROM AUTHOR]

The conversion of rainforests into agriculture resulted in massive changes in species diversity and community structure. Although the conservation of the remaining rainforests is of utmost importance, identifying and creating a biodiversity‐friendly agriculture landscape is vital for preserving biodiversity and their functions.Biodiversity studies in agriculture have often been conducted at low elevations. In this study, we compared the functional diversity (FD), phylogenetic diversity (PD) and community structure of birds along an interacting gradient of land use (protected rainforest, reserve buffer and agriculture) and elevation (low, middle and high) in Sri Lanka. Then, we measured the compositional change by identifying how ecological traits (dietary guild, vertical strata, body mass and dispersal ability) and conservation characteristics (forest dependence and threatened status) responded to land use types.Elevation and land use interacted with each other to shape bird FD. Depending on the elevation, FD in agriculture was either higher or similar to forest. However, PD was similar across all elevation and land use types. Bird community structure in forest was functionally and phylogenetically clustered in comparison to agriculture. Insectivorous birds declined from forest to agriculture, and so did understorey and middle‐storey birds. But frugivorous and canopy birds did not change across land use types, while nectarivores, granivores and carnivores proliferated in agriculture. Forests were dominated by birds with low dispersal abilities, but birds in agriculture had more evenly distributed dispersal abilities. About half of all the individuals in agriculture were composed of forest species, several of which were threatened.Synthesis and applications. Most farmers in Sri Lanka practice agriculture on small farms (c. 2 ha) and rely on services (e.g. pest control and pollination) provided by biodiversity for their livelihoods. Our results underline the important role of these heterogeneous agriculture landscapes in maintaining high functional diversity (FD) and harbouring several threatened species. While FD in agriculture was comparatively high, conservation decisions based on land use alone cannot be reliable, because land use effects were elevation dependent. Thus, priority setting exercises aimed at designing optimal agriculture landscapes should consider landscape features, in combination with elevation, to benefit both people and wildlife outside protected areas. [ABSTRACT FROM AUTHOR]

A single adverse environment event can threaten the survival of small‐ranged species while random fluctuations in population size increase the extinction risk of less‐abundant species. The abundance–range‐size relationship (ARR) is usually positive, which means that smaller‐ranged species are often of low abundance and might face both problems simultaneously.The ARR has been reported to be negative on tropical islands, perhaps allowing endemic species in such environments to remain extant. But there is a need to understand how endemism and land‐use interact to shape ARR.Using 41 highly replicated transects along the full elevational gradient of Sri Lanka, we determined the following: (a) the direction of ARR, (b) if endemism affects ARR and (c) if land‐use (rainforest, buffer and agriculture) changes ARR differently for endemics and non‐endemics. Additionally, (d) we identified endemics that had both lower abundances and smaller range sizes, and ranked them from most threatened (specific to rainforests) to least threatened using a weighted‐interaction nestedness estimator.(a) We found a positive relationship between species abundances and range size. This positive ARR was maintained among endemic and non‐endemic species, across land‐use types and at local and regional scales. (b) The ARR interacted with endemicity and land‐use. Endemics with smaller range sizes had higher abundances than non‐endemics, and particularly higher in rainforests compared to agriculture. In contrast, species with larger range sizes had similar abundances across endemicity and land‐use categories. Many endemics with smaller range sizes are globally threatened; therefore, higher abundances may buffer them from extinction risks. (c) Nine (29%) endemics had both below average abundance and elevational range size. The nestedness estimator ranked the endemics Sri Lanka Whistling Thrush Myophonus blighi, Red‐faced Malkoha Phaenicophaeus pyrrhocephalus, Sri Lanka Thrush Zoothera imbricata and White‐faced Starling Sturnornis albofrontus as the four most vulnerable species to local extinction risk, which corresponds to their global extinction risk.We demonstrate that ARR can be positive on tropical islands, but it is influenced by endemism and land‐use. Examining shifts in ARR is not only important to understand community dynamics but can also act as a tool to inform managers about species that require monitoring programmes. [ABSTRACT FROM AUTHOR]

Anthropogenic activities influence ongoing selective regimes leading to changes in phenotypic variation of plants and animals. The reduction of phenotypic variation may decrease populations' ability to cope with environmental changes. To counteract the increasing risk of extinction of affected populations, it is important to rescue intraspecific variability, assuring higher success of establishment and persistence under global changes.We evaluated whether it is possible to revert phenotypic changes caused by humans using as study case a bird‐dispersed palm that presents seed size reduction due to defaunation of large‐gaped frugivores. We investigated how defaunation changes the seed size profile of each population by evaluating the coefficient of variation, mean and percentage of large phenotypes of produced and dispersed seed sizes. Simple theoretical models were used to simulate the success of two restoration strategies: (a) direct reintroduction of missing phenotypes that were originally found in the species and (b) reintroduction of large‐bodied frugivores to restore the ecological function of large‐seed dispersal. Here we discuss the importance of rescuing phenotype states in restoration strategies.We found that defaunation changes the seed size profile by reducing the size of produced and dispersed seeds. By adding missing phenotypes one time, population mean seed size decreased back to phenotypically depauperated scenarios in eight generations. Conversely, large seed sizes could be rescued in approximately five generations after seed dispersal processes generated by large seed dispersers were re‐established.To rescue and sustain phenotypes such as large seed sizes in palm populations is necessary to restore the seed dispersal processes by large frugivores or add missing phenotypes continuously over time. The restoration of the seed dispersal processes by large frugivores has additional value over seed addition because it would benefit other bird‐dispersed species and, therefore, may be crucial to face ongoing global change scenarios.Synthesis and applications. Defaunation leads to character displacement within decades, having impact on populations, species and ecosystems. To prevent species extinction is paramount that phenotype variation is preserved. We propose the inclusion of phenotype restoration of wild populations as a goal for restoration framework. [ABSTRACT FROM AUTHOR]

Many agamid lizards are known to show sexual dimorphism in body shape, colour and ornamentation or a combination of these traits. Adult males ofSalea horsfieldiihave a discontinuous dorsal crest at the nuchal region, which is a sexually dimorphic character. However, there is no information about the age or size at which this dimorphic ornamentation develops and if the species exhibits sexual shape dimorphism (SShD). The authors studied the morphology ofS. horsfieldiiand found that its ornamentation is an ontogenetically stable character present in all males, including juveniles. Seven morphological characters were measured to determine if they exhibited SShD at adult and juvenile stages. Analysis of covariance was used to identify differences in morphology between sexes. The results show that only adults exhibited SShD, but not juveniles. Adult males had larger head and foot lengths in comparison to females of the same size. Larger head length in adult males is a sexual fitness trait, which increases bite-force during intra-sexual combats. Although the presence of sexually dimorphic ornamentation right from the juvenile stage is rare in agamids,S. horsfieldiiis an exception . The role of sexually dimorphic ornamentation at juvenile stages remains unknown and requires further investigation. [ABSTRACT FROM AUTHOR]

Classical biological control agents fail to achieve an impact on their hosts for a variety of reasons and an understanding of why they fail can help shape decisions on subsequent releases. OrnamentalFicus microcarpais a widely planted avenue fig tree that is invasive in countries where its pollinator (Eupristina verticillata) is also introduced. This tree also supports more than 20 species of non-pollinating fig wasps (NPFW) that feed in the figs and have the potential to reduce the plant’s reproduction.Odontofroggatia galili, one of the most widely introduced NPFW, has larvae that develop in galled ovules that might otherwise develop into seeds or support pollinator larvae. We examined the distribution and relative abundance of the pollinator andO. galilionF. microcarpain China, towards the northern limit of the tree’s natural range, and in Italy where the two species have been introduced. Where they co-existed, we also recorded the impact of varying densities ofO. galilionF. microcarpaseed and pollinator production.O. galiliandE. verticillatadisplayed contrasting habitat preferences in China, withO. galilialmost absent from warmer sites.O. galiliabundance and sex ratios varied between the natural and introduced ranges. Figs with moreO. galilicontained fewer seeds and pollinator offspring, but reproduction was rarely inhibited totally. Additional species with a greater impact in the figs they occupy are needed if biocontrol ofF. microcarpais to be effective. [ABSTRACT FROM PUBLISHER]

Traditional assessments of anthropogenic impacts on biodiversity often ignore hunting pressure or use subjective categories (e.g. high, medium or low) that cannot be readily understood by readers or replicated in other studies. Although animals often appear tame in habitats without hunting compared to habitats with hunting, few studies have demonstrated such effects. We determined the flight initiation distance (FID; i.e. human-animal distance when the animal begins to flee) of a common frugivorous bird of Southeast Asia, Sooty-headed Bulbul (Pycnonotus aurigaster) across a gradient of hunting pressures in Xishuangbanna, Yunnan, SW China. Controlling for confounding effects, we show that FID increased with hunting pressure, which was quantitatively measured through encounters with hunters. As FIDs respond more specifically to hunting than other defaunation metrics, we suggest they can be used as behavioral indicators of hunting pressure in developing conservation strategies. [ABSTRACT FROM AUTHOR]

The primary approach used to conserve tropical biodiversity is in the establishment of protected areas. However, many tropical nature reserves are performing poorly and interventions in the broader landscape may be essential for conserving biodiversity both within reserves and at large. Between October 2010 and 2012, we conducted bird surveys in and around a recently established nature reserve in Xishuangbanna, China. We constructed a checklist of observed species, previously recorded species, and species inferred to have occurred in the area from their distributions and habitat requirements. In addition, we assessed variation in community composition and habitat specificity at a landscape-scale. Despite the fact that the landscape supports a large area of natural forest habitat (~50,000 ha), we estimate that >40% of the bird fauna has been extirpated and abundant evidence suggests hunting is the primary cause. A large proportion (52%) of the bigger birds (>20 cm) were extirpated and for large birds there was a U-shaped relationship between habitat breadth and extirpation probability. Habitat specificity was low and bird communities were dominated by widespread species of limited conservation concern. We question whether extending tropical protected area networks will deliver desired conservation gains, unless much greater effort is channeled into addressing the hunting problem both within existing protected areas and in the broader landscape. [ABSTRACT FROM AUTHOR]

Protected areas (including other effective area-based conservation measures) are a cornerstone of biodiversity conservation. Many countries are increasingly committed to expanding protected area coverage to 30%, which requires an increase in global annual spending from $24b to ~$140b (between $103b and $177b). We find that by trading nature-based carbon credits in voluntary carbon markets at the current average market price of $5 t−1CO 2 , 79 countries and territories can expand protected areas without capital deficit, together generate return on investments of $121b yr−1 and sequester 3 GtCO 2 eyr−1. Another 30 countries can meet at least half of their investment costs, and sequester an additional 2.8 GtCO 2 e yr−1. Additionally, we show that protection can extend to 33% of the Key Biodiversity Areas (KBAs) outside the existing protected area network. Our results point to the largely untapped potential of nature-based climate solutions to accelerate protected area expansion, thereby conserving biodiversity and mitigating climate change. [ABSTRACT FROM AUTHOR]

The usage of invasive tagging methods to assess lizard populations has often been criticised, due to the potential negative effects of marking, which possibly cause increased mortality or altered behaviour. The development of safe, less invasive techniques is essential for improved ecological study and conservation of lizard populations. In this study, we describe a photographic capture-recapture (CR) technique for estimating Draco dussumieri (Agamidae) populations. We used photographs of the ventral surface of the patagium to identify individuals. To establish that the naturally occurring blotches remained constant through time, we compared capture and recapture photographs of 45 pen-marked individuals after a 30 day interval. No changes in blotches were observed and individual lizards could be identified with 100% accuracy. The population density of D. dussumieri in a two hectare areca-nut plantation was estimated using the CR technique with ten sampling occasions over a ten day period. The resulting recapture histories for 24 individuals were analysed using population models in the program CAPTURE. All models indicated that nearly all individuals were captured. The estimated probability for capturing D. dussumieri on at least one occasion was 0.92 and the estimated population density was 13±1.65 lizards/ha. Our results demonstrate the potential for applying CR to population studies in gliding lizards (Draco spp.) and other species with distinctive markings. [ABSTRACT FROM AUTHOR]

The usage of invasive tagging methods to assess lizard populations has often been criticised, due to the potential negative effects of marking, which possibly cause increased mortality or altered behaviour. The development of safe, less invasive techniques is essential for improved ecological study and conservation of lizard populations. In this study, we describe a photographic capture-recapture (CR) technique for estimating Draco dussumieri (Agamidae) populations. We used photographs of the ventral surface of the patagium to identify individuals. To establish that the naturally occurring blotches remained constant through time, we compared capture and recapture photographs of 45 pen-marked individuals after a 30 day interval. No changes in blotches were observed and individual lizards could be identified with 100% accuracy. The population density of D. dussumieri in a two hectare areca-nut plantation was estimated using the CR technique with ten sampling occasions over a ten day period. The resulting recapture histories for 24 individuals were analysed using population models in the program CAPTURE. All models indicated that nearly all individuals were captured. The estimated probability for capturing D. dussumieri on at least one occasion was 0.92 and the estimated population density was 13±1.65 lizards/ha. Our results demonstrate the potential for applying CR to population studies in gliding lizards (Draco spp.) and other species with distinctive markings. [ABSTRACT FROM AUTHOR]

Cnemaspis heteropholis Bauer, 2002 was hitherto defined based only on its holotype, an adult female collected from Gund hill range, Western Ghats, India. Recently we observed adult male and juvenile specimens of this species at Agumbe, ca. 200km south of its type locality and consequently we recharacterize and expand the definition of this species by providing information about intraspecific variation based on the new specimens. Colouration in life and natural history data are also provided. [ABSTRACT FROM AUTHOR]

We analyzed the species composition and abundance of birds and mammals at a fruiting hemi-epiphytic fig (Ficus caulocarpa) in Maliau Basin, Sabah, Malaysia. Observations were conducted for 32 hours over five days. Forty-four species of birds and three mammal species were recorded. Of these, 28 birds and 2 mammals fed on the figs. In addition, nine species of insectivorous or omnivorous birds that did not feed on the figs were observed foraging in the tree, presumably on the large quantities of fig wasps produced. Inter- and intra-specific aggression was also observed among the species foraging in the tree. Overall the assemblage of large birds, such as hornbills, and mammals was poor, which seems to be due to the small size of the figs (<6 mm diameter) rather than a scarcity of these animals in the area. In contrast, the diversity of smaller bird species, especially the Pycnonotidae (Bulbuls) which comprised 13 species and 68% of visits, was high. Our results suggest fig-frugivore interactions may be more finely structured than reports from other, less pristine sites in Asia have indicated. Moreover, 34% of the birds observed are threatened or more severely endangered. We suggest that planting of hemi-epiphytic fig seedlings could be used to enhance the conservation value of small reserves and degraded forests, and that observations at fruiting figs could be used as an efficient method for assessing how well reserves are protected. [ABSTRACT FROM AUTHOR]

Understory avian insectivores are especially sensitive to deforestation, although regional differences in how these species respond to human disturbance may be linked to varying land-use histories. South Asia experienced widespread conversion of forest to agriculture in the nineteenth century, providing a comparison to tropical areas deforested more recently. In Sri Lanka and the Western Ghats of India, we compared understory insectivores to other guilds, and to insectivores with different vertical strata preferences, both inside mixed-species flocks and for the whole bird community. Overall species richness did not change across the land-use gradient, although there was substantial turnover in species composition between land-use types. We found that the proportion of species represented by insectivores was ~1.14 times higher in forest compared to agriculture, and the proportion of insectivores represented by understory species was ~1.32 times higher in forests. Mass-abundance relationships were very different when analyzed on mixed-species flocks compared to the total community, perhaps indicating reduced competition in these mutualisms. We show that South Asia fits the worldwide pattern of understory insectivores declining with increased land-use intensity, and conclude that these species can be used globally as indicator and/or umbrella species for conservation across different disturbance time scales. [ABSTRACT FROM AUTHOR]

Windbreaks often form networks of forest habitats that improve connectivity and thus conserve biodiversity, but little is known of such effects in the tropics. We determined bird species richness and community composition in windbreaks composed of remnant native vegetation amongst tea plantations (natural windbreaks), and compared it with the surrounding primary forests. Fifty-one, ten-minute point counts were conducted in each habitat type over three days. Despite the limited sampling period, our bird inventories in both natural windbreaks and primary forests were nearly complete, as indicated by bootstrap true richness estimator. Bird species richness and abundance between primary forests and windbreaks were similar, however a difference in bird community composition was observed. Abundances of important functional groups such as frugivores and insectivores did not vary between habitat types but nectarivores were more abundant in windbreaks, potentially as a result of the use of windbreaks as traveling routes, foraging and nesting sites. This preliminary study suggests that natural windbreaks may be important habitats for the persistence of bird species in a production landscape. However, a better understanding of the required physical and compositional characteristics for windbreaks to sustain bird communities is needed for effective conservation management. [ABSTRACT FROM AUTHOR]

Despite the important contribution of fungi to forest health, biomass turnover and carbon cycling, little is known about the factors that influence fungal phenology. Therefore, in order to further our understanding on how macrofungal fruiting patterns change along a gradient from temperate to tropical climate zones, we investigated the phenological patterns of macrofungal fruiting at five sites along a combined altitudinal and latitudinal gradient in SW China and NW Laos, ranging from temperate to tropical climates. Observations were conducted in the dominant land use types at these study sites: mixed forest (all sites), coniferous forest (temperate sites) and grassland (temperate sites). In total, 2866 specimens were collected, belonging to 791 morpho species, 162 genera, and 71 families. At the site level, the fruiting of ectomycorrhizal (EcMF) and saprotrophic fungi (SapF) occurred at the same time among all land use types. The fruiting season of fungi in the tropical sites began earlier and ended later compared to that of fungi in the temperate sites, which we attribute mainly to the higher temperature and more abundant rainfall of the tropical areas. EcMF taxa richness in temperate forests (both coniferous and mixed forest) showed a distinct peak at the end of the rainy season in August and September, while no significant peak was observed for SapF taxa richness. Neither functional fungal groups showed significant seasonal fluctuations in tropical areas. The temporal turnover of fungal fruiting significantly increased with the shift from tropical to temperate forests along the elevation gradient. In the grasslands, macrofungal abundance was less than 22% of that of corresponding forest sites, and taxa richness was 42% of that of corresponding forest sites. Fungal fruiting showed no significant fluctuations across the rainy season. This work represents a case study carried out over one year, and further measurements will be needed to test if these results hold true in the longer term. [ABSTRACT FROM AUTHOR]

Habitat fragmentation in heterogeneous landscapes is a non-random process, with farmers selecting lands with flat topography and fertile soils. To understand the persistence of biodiversity in forest fragments in such landscapes, it is necessary to distinguish between factors associated with fragmentation (e.g., area and distance to edge) and characteristics of where fragments are located (e.g., topography and soil conditions). Location factors have been previously demonstrated to be important in explaining the persistence of trees in fragments in the environmentally diverse region of Xishuangbanna, China (Liu and Slik, Biological Conservation, 2014). However, it is unknown how location factors influence more mobile, short-lived organisms. We sampled 42 of the previous study's plots for birds and herpetofauna across two years. A multi-model inference approach indicated that topography was the most important predictor of amphibian diversity, with valleys having more than three times the species in other locations. Topography interacted with fragment size for bird species, and particularly forest interior (FI) species: diversity in valley plots climbed strongly with fragment area, but the relationship between area and diversity was less strong in other locations. Soil type (limestone or not) most strongly influenced the score of plots on the first axis of a NMDS ordination of FI birds. These results suggest that managers should consider the location of fragments in the landscape in prioritizing forest fragments for protection. For Xishuangbanna, all valley fragments are important to protect amphibians; amalgamating them into large fragments > 1000 ha will make them most useful for bird conservation. [ABSTRACT FROM AUTHOR]

We report the first record of the three-banded skink Eutropis trivittata (Hardwicke and Gray, 1827) (Reptilia: Scincidae) for Andhra Pradesh, India, based on a specimen from Araku, Vishakapatnam district. This report also helps in understanding the distribution of this species in South East India. [ABSTRACT FROM AUTHOR]

Birds, bats and ants are recognised as significant arthropod predators. However, empirical studies reveal inconsistent trends in their relative roles in top-down control across strata. Here, we describe the differences between forest strata in the separate effects of birds, bats and ants on arthropod densities and their cascading effects on plant damage. We implemented a factorial design to exclude vertebrates and ants in both the canopy and understorey. Additionally, we separately excluded birds and bats from the understorey using diurnal and nocturnal exclosures. At the end of the experiments, we collected all arthropods and assessed herbivory damage. Arthropods responded similarly to predator exclusion across forest strata, with a density increase of 81% on trees without vertebrates and 53% without both vertebrates and ants. Additionally, bird exclusion alone led to an 89% increase in arthropod density, while bat exclusion resulted in a 63% increase. Herbivory increased by 42% when vertebrates were excluded and by 35% when both vertebrates and ants were excluded. Bird exclusion alone increased herbivory damage by 28%, while the exclusion of bats showed a detectable but non-significant increase (by 22%). In contrast, ant exclusion had no significant effect on arthropod density or herbivory damage across strata. Our results reveal that the effects of birds and bats on arthropod density and herbivory damage are similar between the forest canopy and understorey in this temperate forest. In addition, ants were not found to be significant predators in our system. Furthermore, birds, bats and ants appeared to exhibit antagonistic relationships in influencing arthropod density. These findings highlight, unprecedentedly, the equal importance of birds and bats in maintaining ecological balance across different strata of a temperate forest., (© 2024 The Author(s). Journal of Animal Ecology © 2024 British Ecological Society.)

The relationship between β-diversity and latitude still remains to be a core question in ecology because of the lack of consensus between studies. One hypothesis for the lack of consensus between studies is that spatial scale changes the relationship between latitude and β-diversity. Here, we test this hypothesis using tree data from 15 large-scale forest plots (greater than or equal to 15 ha, diameter at breast height ≥ 1 cm) across a latitudinal gradient (3-30 o ) in the Asia-Pacific region. We found that the observed β-diversity decreased with increasing latitude when sampling local tree communities at small spatial scale (grain size ≤0.1 ha), but the observed β-diversity did not change with latitude when sampling at large spatial scales (greater than or equal to 0.25 ha). Differences in latitudinal β-diversity gradients across spatial scales were caused by pooled species richness (γ-diversity), which influenced observed β-diversity values at small spatial scales, but not at large spatial scales. Therefore, spatial scale changes the relationship between β-diversity, γ-diversity and latitude, and improving sample representativeness avoids the γ-dependence of β-diversity., Competing Interests: The authors have no competing interests.

Large tracts of tropical rainforests are being converted into intensive agricultural lands. Such anthropogenic disturbances are known to reduce species turnover across horizontal distances. But it is not known if they can also reduce species turnover across vertical distances (elevation), which have steeper climatic differences. We measured turnover in birds across horizontal and vertical sampling transects in three land-use types of Sri Lanka: protected forest, reserve buffer and intensive-agriculture, from 90 to 2100 m a.s.l. Bird turnover rates across horizontal distances were similar across all habitats, and much less than vertical turnover rates. Vertical turnover rates were not similar across habitats. Forest had higher turnover rates than the other two habitats for all bird species. Buffer and intensive-agriculture had similar turnover rates, even though buffer habitats were situated at the forest edge. Therefore, our results demonstrate the crucial importance of conserving primary forest across the full elevational range available., (© 2017 The Author(s).)

Owls have the potential to be keystone species for conservation in fragmented landscapes, as the absence of these predators could profoundly change community structure. Yet few studies have examined how whole communities of owls respond to fragmentation, especially in the tropics. When evaluating the effect of factors related to fragmentation, such as fragment area and distance to the edge, on these birds, it is also important in heterogeneous landscapes to ask how 'location factors' such as the topography, vegetation and soil of the fragment predict their persistence. In Xishuangbanna, southwest China, we established 43 transects (200 m×60 m) within 20 forest fragments to sample nocturnal birds, both visually and aurally. We used a multimodel inference approach to identify the factors that influence owl species richness, and generalized linear mixed models to predict the occurrence probabilities of each species. We found that fragmentation factors dominated location factors, with larger fragments having more species, and four of eight species were significantly more likely to occur in large fragments. Given the potential importance of these birds on regulating small mammal and other animal populations, and thus indirectly affecting seed dispersal, we suggest further protection of large fragments and programs to increase their connectivity to the remaining smaller fragments.

The usage of invasive tagging methods to assess lizard populations has often been criticised, due to the potential negative effects of marking, which possibly cause increased mortality or altered behaviour. The development of safe, less invasive techniques is essential for improved ecological study and conservation of lizard populations. In this study, we describe a photographic capture-recapture (CR) technique for estimating Draco dussumieri (Agamidae) populations. We used photographs of the ventral surface of the patagium to identify individuals. To establish that the naturally occurring blotches remained constant through time, we compared capture and recapture photographs of 45 pen-marked individuals after a 30 day interval. No changes in blotches were observed and individual lizards could be identified with 100% accuracy. The population density of D. dussumieri in a two hectare areca-nut plantation was estimated using the CR technique with ten sampling occasions over a ten day period. The resulting recapture histories for 24 individuals were analysed using population models in the program CAPTURE. All models indicated that nearly all individuals were captured. The estimated probability for capturing D. dussumieri on at least one occasion was 0.92 and the estimated population density was 13±1.65 lizards/ha. Our results demonstrate the potential for applying CR to population studies in gliding lizards (Draco spp.) and other species with distinctive markings.