Bamboos are mainly distributed in subtropical to tropical areas. Bamboos provide numerous ecosystem services, while the expansion of bamboo gives negative impacts on forest ecosystems. Despite big impacts of bamboos on a forest ecosystem, ecological characteristics of bamboo remain poorly understood. The spatial distributional patterns of three bamboo species, Cephalostachyum pergracile, Bambusa polymorpha, and Dinochloa maclellandii, were studied in a commercial tree plantation of native deciduous tree species in the Bago Mountains, Myanmar. A point process analysis revealed a clumped distribution for each bamboo species. The distributional overlapping of the species was analysed for every pair of two species. The distribution of C. pergracile was little overlapped with those of D. maclellandii and B. polymorpha. Cephalostachyum pergracile was significantly more abundant on gently sloping ridges, whereas D. maclellandii was more abundant on a steeply sloping site. Bambusa polymorpha did not show these patterns with topography. The exclusive distribution of C. pergracile and D. maclellandii may be, at least partly, explained by the opposite topographic preferences of the species. Cephalostachyum pergracile tended to be found far from large trees that cast shade, although B. polymorpha tended to be found with large trees, suggesting that B. polymorpha may be more shade tolerant than C. pergracile. The difference in shade tolerance may contribute to the exclusive distribution of the species. The habitat preference information obtained in this study will contribute to sound bamboo management practices in Myanmar and enable bamboo population sizes to be increased through creation of favourable habitats in forests.

Sipunculans are non-segmented marine worms with an anterior retractable introvert, which are commonly included in Annelida based on molecular phylogenetic and phylogenomic analyses. They generally burrow in the soft sediments or live inside the crevices of hard substrata (e.g. calcareous/coralline rocks). However, members of some sipunculan genera (mainly Phascolion and Aspidosiphon) are known to have a peculiar habit of dwelling in vacant shells of gastropods or scaphopods. In this study, we investigated the shell utilization and preference pattern of the species of Phascolion and Aspidosiphon in Japan. We collected 302 sipunculans, comprising 273 and 29 individuals in Phascolion and Aspidosiphon, respectively, from 57–800 m depth of three study sites in the Pacific coast of Honshu Island, Japan. The species of Phascolion were found in vacant shells of 38 genera of 27 families of gastropods and six genera of four families of scaphopods, whereas the species of Aspidosiphon were found in 11 genera of 11 families of gastropods and one genus of scaphopod. These results suggest that members of each genus use a wide range of gastropod and scaphopod shells. The body size of the sipunculans was positively correlated with the shell size, suggesting that they change the shells as they grow. Furthermore, we investigated the shell preference of Phascolion species by comparing morphological characteristics of shells occupied and unoccupied by sipunculans. Generalized linear mixed model (GLMM) analyses suggest that the species of Phascolion tend to use long and narrow shells. Such shells likely fit well the elongated trunk of sipunculans.

This research investigates the influence of environmental parameters that are known to affect bdelloid rotifer species richness and composition in temperate zones on the genus Rotaria in tropical zone. Our study analysed species richness and composition of the genus Rotaria from 390 samples collected from several types of aquatic habitats in Thailand. Coordinates, elevation, limnological parameters such as water temperature, conductivity, total dissolved solids, salinity, dissolved oxygen and pH were measured. A total of nine species was recorded. Of these, one species, Rotaria macrura (Ehrenberg, 1832), was a new record for Thailand and new to the oriental region, and was a yet undescribed species, Rotaria sp. The species diversity of this genus increased from eight to 10 species. The presence or absence of the genus Rotaria was significantly influenced by dissolved oxygen and habitat type. For the samples where the genus occurred, species richness was not affected by any of the limnological or bioclimatic variables. Differences in species composition were affected only by habitat type. The results support former suggestions that common abiotic parameters do not seem to strongly influence diversity in bdelloids, whereas major ecological differences between habitats influence bdelloid occurrence.

The endemic, Critically Endangered greater Bermuda land snail Poecilozonites bermudensis is known from only two relict subpopulations. Little is known of its habitat preferences in the wild. Observations of released zoo-reared P. bermudensis suggested an affinity for limestone, which we investigated on Port's Island. Previous qualitative observations on Port's Island suggested an aversion to the litter of the invasive tree Casuarina equisetifolia, which we examined. Additionally, we hypothesized that snail abundance would increase with elevation, distance from the sea, and with increased plant species diversity. During 2 May–14 June 2018, we found 558 live P. bermudensis at 70 sites across Port's Island. We found no correlation between the number of live snails at a site and either the number of plant species, elevation or distance from the shoreline, but snails were significantly less abundant at sites dominated by C. equisetifolia. Significantly more snails were found around limestone features, indicating future reintroductions and searches for any undiscovered subpopulations should focus on limestone features where C. equisetifolia is absent.

The description of the movements and habitat preference of marine fishes is essential to understand their biology and in the evaluation of commercially exploited species and the conservation of endangered ones. In this regard, little is known about the movements of the totoaba (Totoaba macdonaldi), despite its being listed as critically endangered and having been a relevant fishery resource in the past century in Mexico. Totoaba is a fish species endemic to the Gulf of California characterized by late maturation, prolonged life and annual reproduction. Totoaba has maintained its known historical distribution range, although its movements and habitat occupancy in the water column have remained poorly understood. The present study describes, for the first time and at a daily fine scale, the vertical movements and habitat preferences of the totoaba in the Upper Gulf of California. Pop-up satellite archival tags (PSATs) were used to record depth and temperature at 4-minute intervals. Ten individuals were caught and tagged in May 2016 in the Upper Gulf of California and Colorado River Delta Biosphere Reserve. All PSATs were either prematurely released or lost. Data derived from two recovered tags that saved data for 43 and 75 tracking days, respectively, were analysed. The results showed that tagged fishes moved southward to the vicinity of Angel de la Guarda Island; these are consistent with spatial displacement patterns reported in the literature, with a linear displacement of 223 km from deployment to pop-up sites. Fish spent 47% of the time within a depth range of 25–35 m. Depth increased to 70 m for one fish in early summer (late June). The preferred temperature of fishes ranged between 21–23°C. A generalized linear model revealed that vertical movement was influenced by temperature. The vertical displacement of the totoaba shows a diurnal variation that may be associated with the distribution of its prey. Further work is needed to test this hypothesis with a larger number of organisms.

Natural habitat degradation often involves the reduction or disappearance of bee species. In Africa, stingless bees are hunted for honey, which is used as food, for medicinal purposes, and for traditional rituals. Severe habitat degradation due to human settlement is hypothesized to have a negative impact on the species diversity of the African stingless bee species. In this paper, we assess the impact of habitat degradation on the diversity of five stingless bee species across different habitats in the tropical rainforest of Kenya (indigenous forest, mixed indigenous forest) and its neighbouring landscape (grassland, village) in western Kenya. The species fauna, nest occurrence, and species diversity of the stingless bee species varied across the different habitats. The number of nesting habitats of the meliponine species varied between habitats in the tropical rainforest. Meliponula ferruginea (reddish brown) nested in five habitats, while Meliponula bocandei and Meliponula ferruginea (black) nested only in two habitat types. The species richness decreased within the different types of habitats and the indigenous and mixed indigenous forest contained more species than other habitats. The fauna composition in both homesteads was exclusively similar, while the indigenous and mixed indigenous forests were mostly similar. Similarity in habitat preferences for nesting was revealed between M. bocandei vs Plebeina hildebrandti and M. ferruginea (reddish brown) vs Hypotrigona gribodoi. The natural native indigenous forest had the most diverse community compared to the degraded habitats. There are taxon-specific responses to habitat change; and in our study, there is clear value in conserving the native indigenous forest.

Crownbeard [Verbesina encelioides (Cav.) Benth. & Hook. f. ex. A. Gray # VEEEN (Compositae)] exhibited rapid seedling, vegetative, and reproductive growth. Seed germination under ideal conditions was high and occurred in varying soils except in gravel. It was significantly suppressed under drought and waterlogged conditions and was maximum at 21% moisture regimes. Larger and heavier seeds which exhibited higher germination were produced by the plants growing in open and sand dune habitats. Seedling emergence was highest from surface-sown seeds and least in those sown at 2.5-cm soil depth, beyond which no emergence occurred. High phenotypic plasticity, ecological variability, phenological diversity, seed germination in varied soils and under diverse moisture regimes, quick seedling growth and subsequent establishment, coupled with versatile breeding system, contribute to the successful growth, propagation, and spread of this species in nature in India.

The identification of foraging hotspots able to support the co-existence of multiple top predators provides a potential approach to addressing protection measures for marine ecosystems. In this study, we conducted visual surveys in the central Tyrrhenian Sea to determine areas with simultaneous presence of bottlenose dolphins, four species of seabirds (Audouin's gull, Yellow-legged gull, Yelkouan shearwater and Cory's shearwater), and baitballs occurring at the surface, indicating the presence of potential prey items. We also analysed their occurrence in relation to topography (depth, slope and distance from the shore) and seabed types. Kriging analysis identified areas with simultaneous presence of several marine top predators. Dolphin distribution appeared to be linked to gentle slope (6–10 m) and muddy seabed, possibly associated with prey distribution, whereas the four seabird species were more frequent in areas with a water depth of 100–150 m, gentle slope and muddy seabed, apart from Audouin's gull, which preferred a depth of 10–20 m. Baitball distribution was linked to depth (20–40 m), gentle slope (6–10 m) and muddy seabed. The overlapping presence of bottlenose dolphins, seabirds and baitballs allowed the identification of foraging areas, presumably representing biodiversity and productivity hotspots, located in waters of 50–100 m depth at the mouths of two rivers. This approach provides a promising tool for identifying highly productive coastal areas, and should also be recommended for wider-scale surveys.

The process by which solitary animals evolve to live in groups is a central question in biology. Conspecifics that compete for patchy resources may evolve incipient social behaviours such as group formation and conspecific tolerance when persistent aggressive interactions reduce resource access. In this investigation, a facultative group living species of whip spider was studied to understand the microhabitat resources that support group formation. Although most species of whip spider are solitary and oftentimes cannibalistic, Heterophrynus batesii sometimes aggregate in small groups at the bases of tree trunks. Twenty-five groups of whip spiders and associated tree buttress microhabitats were surveyed at Tiputini Biodiversity Station bordering Yasuní National Park in Eastern Amazonian Ecuador. Tree buttress complexity, surface area and other microhabitat variables were recorded. Heterophrynus batesii aggregated in groups of 2–8 animals and used large, buttressing, complex trees with more leaf litter relative to those available in the environment. This study showed that large groups of whip spiders require more complex microhabitats than smaller groups that were associated with more variable microhabitat parameters. These microhabitats act as patches of limited resources important for the species, and may have led to the evolution of tolerance and facultative group living.

The distribution of nematodes at Cape Hallett and Gondwana station was found to be patchy but consistent, broad-scale habitat preferences were identified. These had been previously noted in McMurdo Dry Valleys soils and on Ross Island, indicating that habitat preferences are consistent across large scales and may play a role in determining range limits. Soil geochemistry, especially salinity, has a strong impact on distribution patterns. The distinct distribution patterns of the four species indicate different niches. Panagrolaimus davidi Timm is the only nematode that can survive within penguin rookeries, where salinity is high but bacterial food is plentiful. Scottnema lindsayae Timm was found across the greatest range of habitats, including the driest sites and largest salinity range. Plectus sp. was found in the wettest sites, with high organic content and low salinity. Eudorylaimus antarcticus Steiner (Yeates) was found at low densities and with other nematodes indicating a dependence on prey availability, an example of a biotic interaction structuring even these simplest ecosystems. Field-identifiable features could be used to identify probable nematode habitats, providing useful information for sampling and the selection of conservation areas.

The Critically Endangered black-faced lion tamarin Leontopithecus caissara has a restricted distribution consisting of small mainland and island populations each with distinct habitats in coastal south-eastern Brazil. The conservation action plan for the species recommends translocation to increase population size and promote genetic exchange among threatened isolated populations, measures that require an understanding of habitat and resource requirements. We investigated habitat selection by the black-faced lion tamarin, comparing habitats and examining frequency of use by two insular groups and two mainland groups. Using this understanding of habitat preferences we were able to refine current estimates of the carrying capacity (K) for this species. Habitats preferred by mainland groups were swamps and inundated areas and secondary forest. Submontane forest was avoided, as were hydromorphic lowland forest and urbanized areas. Island groups used mainly tall lowland forest and arboreal restinga (forest on sandy soil). The finding that L. caissara avoids montane forest sheds light on its restricted distribution to low elevation coastal plains. An estimate of K indicated c. 700 individuals, which could be increased to c. 1,500 with appropriate conservation management measures. Findings agree with the supposition that lion tamarins are typical of mature Atlantic forest, with little altitudinal variation but flexible in their use of successional stages. Future conservation management measures should account for differences in habitat use, selection and differences between island and mainland habitats.

Despite their economic importance, the ecology of many sea cucumber species is poorly understood and factors influencing their habitat preferences remain largely unexplained. The distribution and habitat preference of two sea cucumber species; Holothuria atra and Holothuria edulis were studied off the north-west coast of Sri Lanka by underwater visual census in October 2008. The relationships between the density of each species and the habitat variables, such as mean grain size, organic content (% of dry weight), gravel (%), silt–mud (%), and depth, were examined using a generalized additive model. All these variables except silt–mud have significant influence (P < 0.05) on the habitat association of H. atra. The shallow water (<10 m) seagrass habitat with sediments characterized by 2–3.5% organic content, 15–25% of gravel and coarse sand (0.7–1.2 mm) were the most preferred conditions by H. atra. High densities of H. edulis were found in the shallow (<10 m) depths of rocky areas with algae and seagrass. Favoured bottom sediment conditions of H. edulis were mainly similar to the conditions preferred by H. atra, except organic content which did not significantly influence the habitat preference of this species. The preference towards the specific habitat characteristics seems to be associated with their feeding and protection. An understanding of habitat preference would be useful to improve the management of these sea cucumber populations and enable more precise stock assessment.

The Bale monkey Chlorocebus djamdjamensis is a little-known primate endemic to the south-eastern highlands of Ethiopia. From August 2007 to May 2008 we surveyed to determine the species' habitat preferences and population size in the Odobullu Forest and its range across the Bale Mountains. In Odobullu Forest a total of 136 transects of 1.8–3.0 km were surveyed over a total distance of 280 km. Bale monkey groups were encountered only in bamboo forest, suggesting that the species is a bamboo forest specialist. The density and population size of the Bale monkey in the bamboo forest of Odobullu Forest were estimated to be 121–141 km-2 and 1,718–2,002, respectively. At a larger scale, we assessed the distribution of the Bale monkey in 40% of the bamboo forest across the Bale Mountains within the species’ altitudinal range of 2,400–3,250 m. We identified the areas to be surveyed using a 200 m digital elevation model and a 10-m resolution satellite image. We found the Bale monkey in five areas, three of which are previously unrecorded locations for the species. The Bale monkey is now categorized as Vulnerable on the IUCN Red List, partly based on the results of our surveys. Although extensive, our surveys did not cover all of the species’ potential habitat and further surveys are required across all of the bamboo forest of the Bale Mountains and Sidamo region (the western extension of the Bale Mountains).

Sightings data of two freshwater-dependent cetaceans, the Ganges River dolphin Platanista gangetica gangetica and Irrawaddy dolphin Orcaella brevirostris, were recorded by captains of three nature tourism vessels operating in waterways of the eastern Sundarbans mangrove forest, Bangladesh. These data were used to investigate channel-type preferences and identify cetacean hotspots according to a scoring system based on group, individual and calf encounter rates, the co-occurrence of both species, and encounter rates in neighbouring segments recorded during monsoon, post-monsoon and dry seasons. Six 5-km segments were identified for priority conservation attention from a total of 38 that were surveyed on at least three occasions during each season. An investigation of habitat preferences evaluated 5-km segments that had been surveyed on five or more occasions (n = 69) and assigned them to one of 12 categories defined by channel width, sinuosity and the number of large and small confluences. Significant differences were found between observed and expected frequencies of occurrence in the different segment categories for Ganges River dolphin groups and individuals and for Irrawaddy dolphin individuals. Both Ganges River and Irrawaddy dolphins selected channels with more than two small confluences or at least one large confluence. Understanding the preferred habitat and identifying hotspots of freshwater-dependent cetaceans in the Sundarbans is the first step of a planning process for the potential establishment of a network of protected waterways for these threatened species.

An index of canopy closure was used to estimate closure above the crowns of all trees ≥ 10 cm dbh in 11.11 ha of undisturbed lowland tropical forest at La Selva, Costa Rica. To correct for the efFects of tree size on canopy closure, we used the residual of the regression of the canopy closure index on tree size. Analyses were carried out for the 104 species which had ≥ individuals; a total of 3224 trees were included. Nine species were found to have their crowns in significantly more open conditions than expected by chance and five species were found to have their crowns in significantly more closed conditions than expected by chance (P < 0.05). The remaining 90 species (86.5% of the assemblage) were distributed at random with respect to canopy closure, occupying the available light conditions indiscriminately. Species occurring under higher light levels did not show a narrower range of tolerance than did other species. Most species were found to occur over a substantial proportion of the canopy closure continuum present in the stand; overlap among the great majority of species in the assemblage is extensive. The results support the view that tropical forests comprise assemblages of generalist tree species, and raise questions about the classic notions of gap-phase dynamics.

Greylag (Anscr anser) and Barheaded Geese (Anser indicus) wintering in the Keoladeo National Park, Bharatpur, India, have habitat and food preferences which are comparable to overwintering geese in other parts of the world These geese preferred to eat the dominant grass species in the Park, Paspalum distichum, as determined by a comparison of the mean proportion of Paspalum of the total food eaten by Greylag and Barheaded Geese (0 932 & 0 971, respectively) with the mean availability of Paspalum in the wetland (0 795) However, based on a habitat study at the end of their overwintering season in February 1986, both species of geese used sites with the same amount of Paspalum distichum cover (c 14%) as sites that they did not use (c 14%)

The means of habitat characteristics of sites geese used versus sites they did not use, respectively, are given here in order of their relative preference based on rankings of their standardized means Greylags preferred sites which were grazed concurrently by other species of herbivores (frequency = 0 9 & 0 4), were farther from trees with Painted Stork nests (Mycteria leucocephala; 981 & 887 m) and from trees in general (49 & 26 m), or had deeper water 61 & 49 cm) However, Greylags did not prefer sites which were farther from open water (65 & 223 m), had been cut by hand (frequency = <0 1 & 0 1), were farther from vegetation dominated by Vetivcria zizanioides (668 & 842m), had been bulldozed (frequency = <0 1 & 0 1), or had any amount of cover of the exotic aquatic weed, Eichhornia crassipes (0 0 & 0 3%)

Barheaded Geese preferred sites which were remote from the Park boundary (1156 & 757m), were farther from any road (423 & 235 m), had been grazed by geese in 1984 (0 3 & <0 1), had higher covers of droppings (0 4 & 0 1%), or had been burned in the previous summer (frequency = 02 & 0 1) They did not prefer sites which had deeper water (25 & 61 cm), had been grazed by geese in 1985 (frequency = 0 0 & 0 5), were farther from vegetation dominated by Vetivcria (511 & 733 m), had been bulldozed (frequency = 0 0 & 0 1), or were farther from open water (29 & 115 m) This information can be used to construct management plans for Greylag and Barheaded Geese overwintering in the Keoladeo National Park and other parts of northern India

Spatial distribution patterns and habitat associations of Fagaceae species in a Fagaceae-codominated hill forest in Sumatra were investigated. Ten Fagaceae species believed to be zoochorous (animal-dispersed seed) and five codominant canopy and emergent anemochorous (wind-dispersed seed) species from Anacardiaceae and Dipterocarpaceae were studied. Five Fagaceae species and all codominant anemochorous species were significantly aggregated while the other five Fagaceae species showed a random distribution pattern. The median distance of small saplings from the nearest reproductively mature tree tended to be shorter for aggregated species than spatially random species. This implied that some Fagaceae species dispersed over longer distances than anemochorous species. Relationships between four habitat variables and distribution of the target species were examined with torus-translation tests. Three Quercus and one Lithocarpus species showed positive habitat associations. Two Quercus species aggregated at the preferred habitat, but the others were randomly distributed. Thus tree species with specific habitat preference do not only aggregate at the preferred habitat. The three ridge-specialist Quercus species showed gradual changes in habitat association, which could reflect avoidance of competition among the species. Most of the Lithocarpus species showed little correlation with habitat variables. Coexistence of the three Quercus species partly reflected subtle differences in topographical preferences. Distribution of five of the six Lithocarpus species was unrelated to topography, so other mechanisms must be sought to account for the maintenance of coexistence in this species-rich genus.

We examined the habitat preferences of tigers Panthera tigris in four habitat types in the Sundarbans East Wildlife Sanctuary, Bangladesh. Transect sampling was used to count tiger signs. Mean densities of signs of feeding, resting, defaecation and interaction were significantly different between the four main habitat types (mangrove woodlands, grasslands, sea beaches and transitional areas), whereas movement, scratch-scent-urinal and other signs were not significantly different. This indicates that tigers have habitat preferences for at least some activities. Similar patterns were found in the densities of movement and feeding signs, as well as of resting and defaecation signs, across the four different habitat types. Tigers were found to use soft-barked trees for scratching more often than other types.

The habitat preferences, temporal dynamics in density and the life history of two species of mayflies, Metamonius anceps andMeridialaris chiloeensis, were investigated in a Patagonian mountain stream over a period of one year. Benthic samples weretaken in a low order Nothofagus forested stream. M. anceps was univoltine with small nymphs predominating in winter andemergence occurring in summer. M. chiloeensis showed a bivoltine life cycle with a winter and summer generation, andemergence period in spring and summer. Both species were significantly more abundant in the low water period than in the highdischarge season. Gravels supported significantly more individuals of M. chiloeensis than sand in pools and leaf packs. Temporaloverlap of abundance between species was low. The existence of different life history strategies and the temporal shift of maingenerations and density peaks were critical to allow species coexistence.

A limited sampling campaign on the main island of Îles Kerguelen revealed 170 freshwater diatom taxa, belonging to 29 genera. Four different communities were distinguished in two major groups, being determined principally by habitat type. The Fragilaria vaucheriae–Fragilaria germainii assemblage occurs exclusively in running waters. The three other communities, observed in standing waterbodies, are separated by their geographical position on the island with the Fragilaria exigua–Aulacoseira alpigena and the Fragilaria exigua–Fragilaria vaucheriae assemblages, mainly found in the Lac Studer area and the Fragilaria pinnata var. pinnata assemblage, recorded near the coastal line and the research station. Analysis of different waterbody types revealed the habitat preference of the various diatom taxa and identified a diatom flora for running waters and one preferring stagnant waterbodies.