Vertebrate responses to fruit production in Amazonian flooded and unflooded forests

We document patterns of fruit and vertebrate abundance within an extensive, virtually undisturbed mosaic of seasonally flooded (várzea and igapó) and unflooded (terra firme) forests of central Amazonia. Using phenological surveys and a standardised series of line-transect censuses we investigate the spatial and temporal patterns of immature and mature fruit availability and how this may affect patterns of habitat use by vertebrates in the landscape. All habitats showed marked peaks in fruiting activity, and vertebrate detection rates varied over time for most species both within and between forest types. Many arboreal and terrestrial vertebrates used both types of flooded forest on a seasonal basis, and fluctuations in the abundance of terrestrial species in várzea forest were correlated with fruit availability. Similarly, the abundance of arboreal seed predators such as buffy saki monkeys (Pithecia albicans) and macaws (Ara spp.) were closely linked with immature fruit availability in terra firme forest. We conclude that highly heterogeneous landscapes consisting of terra firme, várzea and igapó forest appear to play an important role in the dynamics of many vertebrate species in lowland Amazonia, but the extent to which different forest types are used is highly variable in both space and time.     

Seasonal patterns of spatial variation in understory bird assemblages across a mosaic of flooded and unflooded Amazonian forests

We examined seasonal patterns of spatial variation in understory bird assemblages across a mosaic of upland and floodplain forests in central Amazonia, where variation in flooding patterns and floodwater nutrient load shapes a marked spatial heterogeneity in forest structure and composition. Despite great differences in productivity due to flooding by either nutrient-rich “white waters” (várzea) or nutrient-poor “black waters” (igapó), bird assemblages in the two floodplain forest types were relatively similar, showing lower abundances than adjacent upland forests (terra firme) and sharing a set of species that were absent or scarce elsewhere. Species that breed in pensile nests overhanging water were abundant in floodplain forests, whereas species that feed on the ground were generally scarce. Flooding affected assemblage dynamics in floodplain forests, with some influx of ground-dwelling species such as ant-following birds from adjacent upland during the low-water season, and the occupation by riverine and aquatic species such as kingfishers during floods. Spatial configuration influenced the seasonal pattern of assemblage structuring, with movements from terra firme occurring primarily to adjacent igapó forests. No such influx was detected in várzea forests that were farther from terra firme and isolated by wide river channels. Results support the view that habitat heterogeneity created by flooding strongly contributes to maintain diverse vertebrate assemblages in Amazonia forest landscapes, even in the case of largely sedentary species such as understory forest birds. Including both upland and floodplain forests in Amazonia reserves may thus be essential to preserve bird diversity at the landscape scale.     

Disentangling stand and environmental correlates of aboveground biomass in Amazonian forests

Tropical forests contain an important proportion of the carbon stored in terrestrial vegetation, but estimated aboveground biomass (AGB) in tropical forests varies two‐fold, with little consensus on the relative importance of climate, soil and forest structure in explaining spatial patterns. Here, we present analyses from a plot network designed to examine differences among contrasting forest habitats (terra firme, seasonally flooded, and white‐sand forests) that span the gradient of climate and soil conditions of the Amazon basin. We installed 0.5‐ha plots in 74 sites representing the three lowland forest habitats in both Loreto, Peru and French Guiana, and we integrated data describing climate, soil physical and chemical characteristics and stand variables, including local measures of wood specific gravity (WSG). We use a hierarchical model to separate the contributions of stand variables from climate and soil variables in explaining spatial variation in AGB. AGB differed among both habitats and regions, varying from 78 Mg ha^?1 in white‐sand forest in Peru to 605 Mg ha^?1 in terra firme clay forest of French Guiana. Stand variables including tree size and basal area, and to a lesser extent WSG, were strong predictors of spatial variation in AGB. In contrast, soil and climate variables explained little overall variation in AGB, though they did co‐vary to a limited extent with stand parameters that explained AGB. Our results suggest that positive feedbacks in forest structure and turnover control AGB in Amazonian forests, with richer soils (Peruvian terra firme and all seasonally flooded habitats) supporting smaller trees with lower wood density and moderate soils (French Guianan terra firme) supporting many larger trees with high wood density. The weak direct relationships we observed between soil and climate variables and AGB suggest that the most appropriate approaches to landscape scale modeling of AGB in the Amazon would be based on remote sensing methods to map stand structure.     

Avian distribution patterns in the Guiana Shield: implications for the delimitation of Amazonian areas of endemism

Aim To develop a methodology for defining the boundaries of the Guianan area of endemism using complementary approaches that include GIS tools, multivariate statistics and analyses of physical barriers in the distribution patterns of an entire endemic avifauna. As a case study, I used the distribution patterns of lowland terra firme forest birds. Location Guiana Shield, northern South America. Methods I identified Guianan endemics using the ornithological literature, subsequently gathering distributional data for these taxa using mainly museum collections and my own fieldwork in the region. I used these distributional data to map the spatial patterns of endemicity in the region and to compare distributions across taxa. I employed community composition data from 34 localities from throughout the Guiana Shield to identify spatial patterns of clustering using an ordination analysis (non‐metric multidimensional scaling), and to recognize the region’s main biogeographical barriers for birds using Monmonier’s algorithm. Results At least 88 avian taxa are restricted to the terra firme forests of the Guianan area of endemism, which is roughly delimited by the Amazon, Negro and Branco rivers. These large rivers, however, are not the only boundaries. I identified seven additional barriers, including medium‐sized rivers, non‐forested areas and mountains, which also contribute to delimiting the area of endemism. Within the endemic avifauna, I identified three distinct distribution patterns. The ordination analysis shows the presence of two distinct avifaunas within the Guiana Shield. Main conclusions Although the proposed boundaries of the Guianan area of endemism are consistent with previously postulated configurations, this study reveals a more complex delimitation than formerly recognized, highlighting the importance of several landscape features besides large rivers, and the existence of three distinct distributional patterns within one endemic avifauna. The Branco/Negro interfluvium, often included within this area of endemism, actually represents a transition zone between two distinct avifaunas. The longstanding view of the Amazon Basin as a mosaic of parapatric areas of endemism delimited by major rivers appears to be an oversimplification, at least for the Guiana Shield. This finding suggests the need for more rigorous approaches to re‐evaluate the traditional boundaries of such areas.     

Habitat change and trade explain the bird assemblage from the La Chimba archaeological site in the northeastern Andes of Ecuador

The nature of tree‐line habitats in the Andes has long been a contentious topic in the ecological literature. Palynological studies suggest that a combination of anthropogenic and natural processes throughout the Holocene contributed to its present form and species composition. This is the first study to use zooarchaeological evidence to reconstruct possible prehistoric changes in these alpine habitats. I analysed the remains of birds from the La Chimba archaeological site in northern Ecuador to assess changes in the bird tree‐line community over three distinct phases (Early, 2640–2390 year BP; Middle, 2390–1994 year BP; Late, 1994–1700 year BP) of this prehistoric settlement. The elevation of this site (3200 m) places it near a steep elevational gradient in vegetation, with the modern tree‐line here at 3500–3600 m. Therefore, non‐local specimens of birds from the lowlands would hint at long‐distance trade. The composition of birds changes through time: species associated with high montane forest and shrubby páramos decrease and species from dry or open montane habitats increase. This trend is dominated by the decrease of Curve‐billed Tinamous Nothoprocta curvirostris (current elevational range 3000–3900 m) and a corresponding increase of specimens of Andean Tinamous Nothoprocta pentlandii (current elevational range 1000–2300 m). The large number of Andean Tinamous is surprising given that presently it occurs no closer than 300 km to the south of the La Chimba site. Overall, 18 of the 43 species of birds identified from La Chimba are likely to be the result of trade. This includes species from the eastern and western lowlands of Ecuador and one possible long‐distance transport from Peru. Prehistoric trade of birds and bird parts was probably common, and prehistoric anthropogenic landscape change and trade in birds should be considered as alternative explanations for species with disjunct populations in and across the Andes.     

Inter‐annual site fidelity and breeding origins of Gray‐cheeked Thrushes in white sand forests of the Peruvian Amazon

White sand terra firme forests are unusual ecosystems scattered across Amazonia, covering just 3% of the basin. These forests differ from surrounding forests in their scleromorphic vegetation, low nutrient content, and propensity to harbor endemics. We report the capture of 62 Gray‐cheeked Thrushes (Catharus minimus) during a study of the understory avifauna of Amazonian white sand forests near Iquitos, Peru, conducted from 20 June to 8 December 2010–2012. We captured and banded Gray‐cheeked Thrushes in white sand (N = 57) and adjacent weathered clay (N = 5) terra firme forests. Sampling for three consecutive days at 19 different sites each year, the inter‐annual site fidelity rate of Gray‐cheeked Thrushes was 4.8% (N = 3). One bird banded in 2010 was recaptured in 2012. Of the 62 birds, 19.3% (N = 12) were recaptured on subsequent days. All recaptures were in white sand forests. The 19.3% recapture rate of Gray‐cheeked Thrushes from sites re‐sampled no more than 2 d in a given year suggests the presence of settled and perhaps territorial birds. Using rectrices from 12 Gray‐cheeked Thrushes, stable‐hydrogen isotope analyses (δ²H) suggest that the geographic breeding or natal origin of all sampled birds was likely northwestern North America. Our results suggest that Gray‐cheeked Thrushes exhibit site fidelity and may concentrate in white sand forests—an uncommon and scattered ecosystem type in western Amazonia. However, annual tracking of individual Gray‐cheeked Thrushes is needed to fully assess regional patterns of settlement and movement, and the connectivity between breeding and wintering areas.     

Peruvian Red Uakaris (<Emphasis Type="Italic">Cacajao calvus ucayalii</Emphasis>) Are Not Flooded-Forest Specialists

In the literature, particularly in primatological books, the Peruvian red uakari (Cacajao calvus ucayalii) is generally considered as a species that is specialized on living in flooded forest, despite existing evidence to the contrary. Here we review all available information on habitats where Cacajao calvus ucayalii have been observed. Most sightings are from terra firme, including palm swamps, or from mixed habitats, including terra firme and flooded forest. Therefore, we conclude that the species is not a flooded-forest specialist, but is flexible in its habitat requirements and generally uses terra firme forests or a mixture of habitats. Proper recognition of habitat requirements is important for understanding the ecoethological adaptations of a species and for appropriate conservation measures.     

Does flood tolerance explain tree species distribution in tropical seasonally flooded habitats?

In the tropics, seasonally flooded forests (SFF) harbor fewer tree species than terra firme (i.e. non-flooded) forests. The low species diversity of tropical flooded forests has been ascribed to the paucity of species with adaptations to tolerate flooding. To test the hypothesis that flooding is the only factor restricting most species from SFF, we compared plant morphological and physiological responses to flooding in 2-month old seedlings of 6 species common to SFF and 12 species common to terra firme forests. Although flooding impaired growth, total biomass, maximum root length and stomatal conductance in most species, responses varied greatly and were species-specific. For example, after 90 days, flooding reduced leaf area growth by 10-50% in all species, except in Tabebuia, a common species from non-flooded habitats. Similarly, flooding had a 5-45% negative effect on total biomass for all species, except in 1 SFF and 1 terra firme species both of which had more biomass under flooding. A principal component analysis, using the above responses to flooding, provided no evidence that SFF and terra firme species differed in their responses to flooding. Flooding also caused reductions in root growth for most species. Rooting depth and root: shoot ratios were significantly less affected by flooding in SFF than in terra firme species. Although flood tolerance is critical for survival in flooded habitats, we hypothesize that responses to post-flooding events such as drought might be equally important in seasonal habitats. Therefore, we suggest that the ability to grow roots under anoxia might be critical in predicting success in inundated habitats that also experience a strong dry season.     

Do miners (Manorina spp.) affect bird assemblages in continuous savanna woodlands in north‐eastern Australia?

Overabundant native species can have a significant cascading effect on other components of wildlife, and those that deplete other species, often promoted by anthropogenic change to vegetation cover and habitat, are called reverse keystone species. Birds in the genus Manorina are widely reported as being such species, and in highly disturbed or fragmented environments, and some intact environments, noisy miners Manorina melanocephala can have a strong negative effect on small passerine species via hyper‐aggressive mobbing. The tropical savannas of northern Australia consist of largely unmodified woodlands, and two species of Manorina occur naturally in this region: the noisy miner and the yellow‐throated miner Manorina flavigula. Therefore, what effect do these species have on bird assemblage in predominantly continuous habitats, relative to other typical determinants of avifauna assemblage such as vegetation structure? We used data collected from bird surveys at 511 sites across northern Queensland (179 noisy miner M. melanocephala sites, 332 yellow‐throated miner M. flavigula sites) between 1998 and 2010. We examined the variation in bird composition at each site due to increasing abundance of Manorina spp. using uni‐ and multivariate techniques. We found total bird richness was significantly lower in sites where noisy and yellow‐throated miner abundances were highest, and passerine species seemed most affected. For species, 45 species varied significantly in abundance with increasing miner numbers, and the overall effect of yellow‐throated miners on other birds seemed more pronounced. However, vegetation structure was generally an equal or more important predictor of avifauna richness and abundance. We conclude that despite the superficially intact nature of northern Australian woodlands, pastoral intensification or poor land management might create disturbances that facilitate increases in the abundance of Manorina, causing localized overabundance and a compounding negative effect on other native bird species.     

Niche partitioning among three montane ground‐dwelling pheasant species along multiple ecological dimensions

Pheasants (order Galliformes) are typical ground‐dwelling birds, having a large body size and weak flight abilities. Sympatric pheasants are expected to share narrower niche space and face more extensive interspecific competition. However, little work has been undertaken simultaneously to investigate niche partitioning among sympatric pheasant species across multiple ecological dimensions. We compared microhabitat use, activity pattern and foraging strategy of sympatric Blood Pheasant Ithaginis cruentus, Buff‐throated Partridge Tetraophasis szechenyii and White Eared‐pheasant Crossoptilon crossoptilon on the Qinghai‐Tibet Plateau, China, to identify potential interspecific niche partitioning along different ecological dimensions in the breeding season. We found that the Buff‐throated Partridge differed significantly from the other two species in microhabitat use, and the three species showed different foraging strategies. It is likely that niche partitioning reduced potential interspecific competition, thus facilitating the species’ stable coexistence. Our study provides practical evidence of multidimensional niche theory within sympatric ground‐dwelling pheasant species, emphasizing that species interactions and coexistence within a guild are often not uni‐dimensional. Given global conservation concern for maintaining bird diversity, we recommend further restriction of yak grazing in these species’ habitat.     

Yellow‐throated miners Manorina flavigula homogenize bird communities across intact and fragmented landscapes

In Australia, the role of noisy miners Manorina melanocephala in biotic homogenization of the avifauna has been well established in modified landscapes, and is listed as a threatening process under national conservation legislation. However, less is known about the effect of the congeneric and more widely distributed yellow‐throated miner, M. flavigula. In this paper we investigate the relative roles of habitat loss and increased dominance by the yellow‐throated miner in avian homogenization and species functional group decline. We examined bird community data collected from 368 woodland sites across three bioregions. For each site there was a local and a landscape scale measure of remnant vegetation cover. We used both multivariate and regression analysis to test the relative influence of yellow‐throated miner abundance and vegetation on bird community composition. There was clear compositional change and homogenization of the avifauna where yellow‐throated miners were present and vegetation cover was low. The abundance of 40 bird species was predicted by combinations of vegetation cover or yellow‐throated miner abundance, and 31 of these regressions included the term yellow‐throated miner. Of these, there was a negative relationship with 23 species, and 19 of these were insectivores or nectarivores. We postulate that the combination of clearing and yellow‐throated miner abundance can interact to disrupt the ecological function of woodlands, by the depletion of insect‐ and nectar‐feeding species and the disturbance to mixed feeding flocks. We propose future research objectives that include a continental‐scale analysis of the determinants of yellow‐throated miner overabundance, the numerical and geographical thresholds of their potential impacts, and the ecological consequences on both avifauna and the woodlands they inhabit.     

Tree Phenology in Adjacent Amazonian Flooded and Unflooded Forests1

Most phenological studies to date have taken place in upland forest above the maximum flood level of nearby streams and rivers. In this paper, we examine the phenological patterns of tree assemblages in a large Amazonian forest landscape, including both upland (terra firme) and seasonally flooded (várzea and igapó) forest. The abundance of vegetative and reproductive phenophases was very seasonal in all forests types. Both types of flooded forest were more deciduous than terra firme, shedding most of their leaves during the inundation period. Pulses of new leaves occurred mainly during the dry season in terra firme, whereas those in the two floodplain forests were largely restricted to the end of the inundation period. Flowering was concentrated in the dry season in all forest types and was strongly correlated with the decrease in rainfall. The two floodplain forests concentrated their fruiting peaks during the inundation period, whereas trees in terra firme tended to bear fruits at the onset of the wet season. The results suggest that the phenological patterns of all forest types are largely predictable and that the regular and prolonged seasonal flood pulse is a major determinant of phenological patterns in várzea and igapó, whereas rainfall and solar irradiance appear to be important in terra firme. The three forest types provide a mosaic of food resources that has important implications for the conservation and maintenance of wide‐ranging frugivore populations in Amazonian forests.     

No short‐term change in avian assemblage following removal of Yellow‐throated Miner (Manorina flavigula) colonies

The overabundance of Yellow‐throated Miner (Manorina flavigula) has been shown to negatively affect the abundance and richness of small birds in areas they occupy, leading to homogenization of the avifauna across the fragmented landscape. In this study, we took advantage of a planned management cull to ask the question, does the removal of Yellow‐throated Miner colonies cause an immediate change in avian species richness and abundance? This cull was undertaken around the Bronzewing Flora and Fauna Reserve (north‐western Victoria, Australia) in order to protect a resident population of endangered Black‐eared Miner (M. melanotis) from hybridization. We conducted avian surveys along roadsides surrounding the reserve at Yellow‐throated Miner colonies (n = 6), control sites with no miners (n = 7), and where colonies were removed (n = 3). We found that the cull was followed by only a very modest increase in the species richness and abundance of small birds, with no significant effects on avian assemblage overall. This result contrasts with far more dramatic increases following culls of other species of miner. Sites where miners were removed were not depauperate of other species prior to the cull, which could have been due to a combination of proximity to refuge for small birds in a neighbouring reserve or the low numbers of miners that made up each culled colony. This study highlights that assumed effects of a management action may be highly dependent upon spatial and temporal context.     

Bird species of black water inundation forests in the Jaú National Park (Amazonas state, Brazil): their contribution to regional species richness

We compared the relative contribution of blackwater inundation forest (igapó) and unflooded (terra firme) forest for regional bird species diversity in the lower Rio Negro region. For analyses of habitat preference we used mist-net samples and an unpublished bird species check-list. The igapó forest had lower bird species diversity than the terra firme forest. However, some 14% of the forest bird species in the region are restricted to igapó forest. Species composition was found to be distinct between the understories of the two forest types. Common forest bird guilds in the Neotropics such as ant-following birds avoid igapó forest. The differential habitat selection among birds in the inundated and unflooded forest is likely to result from vegetation structure and biological interactions such as aggressive behaviour. Since the inundated forest has a typical biota, conservation efforts needs to be directed to protect these habitats. Unfortunately, inundation forests are threatened by several human actions, especially dam construction. The extent of protected areas in the Brazilian Amazon is insufficient for the adequate protection of the inundated habitats, because it includes only 3% of the total area.     

Interspecific variation in gill size is correlated to ambient dissolved oxygen in the Amazonian electric fish Brachyhypopomus (Gymnotiformes: Hypopomidae)

Gymnotiform electric fish assemblage structure is strongly correlated to dissolved oxygen (DO) availability, which exhibits considerable heterogeneity among Amazonian aquatic systems. DO is known to influence the respiratory morphology of gymnotiform fishes, and yet species-level variation among congeners endemic to alternative DO regimes has not been examined. We describe the DO environment experienced by four congeneric species of gymnotiforms (Brachyhypopomus) and correlate this to quantitative variation in a suite of gill metrics. Whitewater floodplain lakes flanking nutrient-rich whitewater rivers are seasonally hypoxic, exhibiting oxygen concentrations close to 0 mg/l from late April until September. In contrast, DO levels in blackwater floodplain lakes and in terra firme forest stream habitats remain high throughout the year. Two common species of Brachyhypopomus restricted to periodically anoxic whitewater floodplain exhibited a substantially greater gill size than two common species restricted to the perpetually well-oxygenated waters of blackwater floodplain lakes and terra firme stream systems. Discriminant Function Analysis (DFA) based on gill metrics separated the species that live in seasonally anoxic whitewater floodplain species from those that live in perpetually-well oxygenated habitats. Our observations suggest a history of adaptive divergence in the gill morphology of Brachyhypopomus associated with oxygen availability.     

Habitat Selection and Use of Space by Bald-Faced Sakis (Pithecia irrorata) in Southwestern Amazonia: Lessons from a Multiyear, Multigroup Study

Population density and distribution in tropical forest vertebrates are directly linked to patterns of use of space relative to habitat structure and composition. To examine how forest type may explain the ranging behavior and high variance in group density observed within the geographic range of bald-faced saki monkeys (Pithecia irrorata), we monitored habitat use of 5 neighboring focal groups of this species in southwestern Amazonia over 3 yr. To test whether sakis are unflooded (terra firme) forest specialists, we compared home range (HR) use to the corresponding availability of 4 main forest types and quantified HR size and activity budgets as a function of forest type. HR size varied from 16 to 60 ha, and saki population density at this scale (12.5 ± 6.4 SD individuals/km²) was more closely related to forest type than to group size. Although sakis were not obligate habitat specialists, groups clearly avoided bamboo forest and preferred terra firme forest. Terra firme forests were associated with small HRs, intensive use, high HR overlap, and territorial defense, all of which suggest that saki densities will be higher in areas dominated by terra firme forest where large patches of bamboo (Guadua spp.) are absent. The increased desiccation and subsequent forest fires expected in this region from the combined impacts of climate change and human land use potentially threaten the long-term viability of old-growth terra firme forest specialists such as sakis. Regional-scale conservation efforts should ensure that extensive blocks of terra firme forest are protected in areas that remain relatively free of bamboo.     

Contrasting genetic diversity and population structure among three sympatric Madagascan shorebirds: parallels with rarity,endemism, and dispersal

Understanding the relative contributions of intrinsic and extrinsic factors to population structure and genetic diversity is a central goal of conservation and evolutionary genetics. One way to achieve this is through comparative population genetic analysis of sympatric sister taxa, which allows evaluation of intrinsic factors such as population demography and life history while controlling for phylogenetic relatedness and geography. We used ten conserved microsatellites to explore the population structure and genetic diversity of three sympatric and closely related plover species in southwestern Madagascar: Kittlitz's plover (Charadrius pecuarius), white‐fronted plover (C. marginatus), and Madagascar plover (C. thoracicus). Bayesian clustering revealed strong population structure in the rare and endemic Madagascar plover, intermediate population structure in the white‐fronted plover, and no detectable population structure in the geographically widespread Kittlitz's plover. In contrast, allelic richness and heterozygosity were highest for the Kittlitz's plover, intermediate for the white‐fronted plover and lowest for the Madagascar plover. No evidence was found in support of the “watershed mechanism” proposed to facilitate vicariant divergence of Madagascan lemurs and reptiles, which we attribute to the vagility of birds. However, we found a significant pattern of genetic isolation by distance among populations of the Madagascar plover, but not for the other two species. These findings suggest that interspecific variation in rarity, endemism, and dispersal propensity may influence genetic structure and diversity, even in highly vagile species.     

Is there genetic connectivity among the critically endangered White‐winged Flufftail (Sarothrura ayresi) populations from South Africa and Ethiopia?

The White‐winged Flufftail (Sarothrura ayresi) is known to occur in the highland marshes of Ethiopia, as well as almost 4000 km in South Africa. The White‐winged Flufftail is listed globally as Critically Endangered. In South Africa the population is estimated to be <50 birds. These birds are severely threatened by habitat destruction. Thus far, no genetic studies have been conducted on S. ayresi to confirm genetic connectivity between the South African and Ethiopian populations. In this study, analysis of mitochondrial and nuclear markers was conducted for White‐winged Flufftail samples from South African and Ethiopian birds, as well as Red‐chested Flufftail (Sarothrura rufa) for species comparison. Analyses of the DNA regions identified three variations between the two populations, supporting the hypothesis that these two populations are not different species or subspecies but are rather one migrating population with different seasonal occupied ranges. However, these results do not exclude the possibility of additional breeding and nonbreeding sites. Low genetic diversity in the populations of White‐winged Flufftails was observed, which needs to be further elucidated with fast evolving co‐dominant markers such as microsatellites, as this low diversity may ultimately contribute to the extinction of the species.     

Avian distribution in treefall gaps and understorey of terra firme forest in the lowland Amazon

We compared the bird distributions in the understorey of treefall gaps and sites with intact canopy in Amazonian terra firme forest in Brazil. We compiled 2216 mist-net captures (116 species) in 32 gap and 32 forest sites over 22.3 months. Gap habitats differed from forest habitats in having higher capture rates, total captures, species richness and diversity. Seventeen species showed a significantly different distribution of captures between the two habitats (13 higher in gap and four higher in forest). Gap habitats had higher capture rates for nectarivores, frugivores and insectivores. Among insectivores, capture rates for solitary insectivores and army ant followers did not differ between the two habitats. In contrast, capture rates were higher in gaps for members of mixed-species insectivore flocks and mixed-species insectivore–frugivore flocks. Insectivores, especially members of mixed-species flocks, were the predominant species in gap habitats, where frugivores and nectarivores were relatively uncommon. Although few canopy species were captured in gap or forest habitats, visitors from forest mid-storey constituted 42% of the gap specialist species (0% forest) and 46% of rare gap species (38% forest). Insectivore, and total, captures increased over time, but did so more rapidly in gap than in forest habitats, possibly as a response to gap succession. However, an influx of birds displaced by nearby timber harvest also may have caused these increases. Avian gap-use in Amazonian terra firme forests differs from gap-use elsewhere, partly because of differences in forest characteristics such as stature and soil fertility, indicating that the avian response to gaps is context dependent.     

Movements and habitat use of the night parrot Pezoporus occidentalis in south‐western Queensland

The nocturnal, cryptic and geographically remote nature of night parrots, combined with their apparent rapid decline, means that very little is known of their biology or ecology. The discovery of a resident population in south‐western Queensland in 2013 provides the first opportunity to undertake detailed studies on this most enigmatic of birds. We attached a radio tag to a bird for 20 days in April 2015 and a GPS tag to another bird for 5 days in May 2016 to study movement patterns and habitat use. Both birds displayed similar behaviour but the GPS‐tagging provided a much finer resolution of spatial data. They called at dusk from their diurnal roosts amongst spinifex hummocks and then flew to more floristically diverse habitats dominated by large‐seeded species to feed. We conducted floristic surveys to describe the feeding grounds of the GPS‐tagged bird and make dietary inferences. This individual spent most of its time in highly diverse but ephemeral habitats, including seasonally inundated plains and depressions associated with the outer Diamantina floodplain and gilgais on ironstone plains. Prolifically seeding ephemeral species, most notably the annual grass Uranthoecium truncatum, dominate these feeding grounds. This work suggests that the habitat mosaic containing roost sites in close proximity to feeding grounds with key seed‐producing species is an important factor, rather than an association with spinifex or samphire alone. Further work is needed to examine movement patterns and habitat use in more typical dry seasons and the impact of cattle grazing on night parrot feeding areas, particularly with regard to seed production. The information presented here is vital for both in situ conservation of the Pullen‐Pullen‐Mt Windsor‐Diamantina population and for setting future research and survey priorities.