12 research outputs found
The Distribution, Natural History and the Conservation Status of Batrachostomus Moniliger (Aves: Podargidae) in Last Two Decades from Sri Lanka
The Sri Lanka frogmouth (Batrachostomus moniliger) is a small-sized nocturnal bird largely restricted to tropical lowland forests with thick undergrowth. The motionless roosting posture as well as their plumage coloration and color patterns (which resemble that of tree stems and branches) enable them to camouflage and thereby avoid predation. Through opportunistic field surveys over a 20-year period (January 1998-February 2018), we surveyed different bioclimatic regions of Sri Lanka covering 500 sites, and documented presence of Sri Lankan frogmouth in 83 of sites. In these 83 sites, we recorded 136 birds including seven nesting pairs and chicks. Our survey confirmed frogmouth presence in four floristic regions of Sri Lanka, particularly from lower elevations (11-767 m). Most sightings were made in lowland rainforests while savannah woodlands had the least number of records; no frogmouths were recorded inside anthropocentric land-cover types such as commercial-scale farmlands or plantations. According to the habitat suitability model we constructed (MaxEnt-based), much of the lowland wet zone, particularly the southwestern corner, was predicted as the most suitable areas for Sri Lankan Frogmouth while the northeastern coastal plains, and the mid-western and northwestern parts of Sri Lanka seemed least suitable. According to The Maxent modelâs internal jackknife test of variable importance, temperature seasonality is the most important predictor of frogmouthâs distribution. Sri Lanka frogmouths have a high fidelity for their roosting sites as they remained in the same tree at least for a week; preferred roosting trees were medium-sized Dicot species with a dense canopy cover and variable canopy heights. These roosting sites are relatively cool, humid with little exposure to direct sunlight. Both roosting and nesting trees were relatively isolated from neighboring canopy trees, thus, the understory surrounding the roosting tree was dense. Six of the nesting sites observed were located in the lowland wet zone rainforests while the other was in savannah woodlands of the intermediate zone. These nests were positioned approximately 66% of maximum canopy height of the host tree. Nests were constructed on relatively thin branches that formed an acute angle against the main stem. These nests are shallow, circular-shaped pads. The nest interior was cushioned with cotton, parts of fishtail palm, and down feathers while the nest exterior contained pieces of lichens and tree bark. Sri Lanka Frogmouthâs home ranges appeared to be very small in nesting season, a maximum of 60 m radius area around the roosting site. Both male and female birds alternate nest-guarding duties through most of the night-time. The major threat for the frogmouth in Sri Lanka includes habitat loss due to expansion of commercial-scale agriculture and monoculture plantations, illicit forest encroachments, and clear-cutting.Keywords: Ecology, Frogmouth, Habitat modeling, Nesting, Threat
A theoretical framework for the ecological role of three-dimensional structural diversity
The three-dimensional (3D) physical aspects of ecosystems are intrinsically linked to ecological processes. Here, we describe structural diversity as the volumetric capacity, physical arrangement, and identity/traits of biotic components in an ecosystem. Despite being recognized in earlier ecological studies, structural diversity has been largely overlooked due to an absence of not only a theoretical foundation but also effective measurement tools. We present a framework for conceptualizing structural diversity and suggest how to facilitate its broader incorporation into ecological theory and practice. We also discuss how the interplay of genetic and environmental factors underpin structural diversity, allowing for a potentially unique synthetic approach to explain ecosystem function. A practical approach is then proposed in which scientists can test the ecological role of structural diversity at bioticâenvironmental interfaces, along with examples of structural diversity research and future directions for integrating structural diversity into ecological theory and management across scales
Harnessing the NEON data revolution to advance open environmental science with a diverse and data-capable community
It is a critical time to reflect on the National Ecological Observatory Network (NEON) science to date as well as envision what research can be done right now with NEON (and other) data and what training is needed to enable a diverse user community. NEON became fully operational in May 2019 and has pivoted from planning and construction to operation and maintenance. In this overview, the history of and foundational thinking around NEON are discussed. A framework of open science is described with a discussion of how NEON can be situated as part of a larger data constellationâacross existing networks and different suites of ecological measurements and sensors. Next, a synthesis of early NEON science, based on >100 existing publications, funded proposal efforts, and emergent science at the very first NEON Science Summit (hosted by Earth Lab at the University of Colorado Boulder in October 2019) is provided. Key questions that the ecology community will address with NEON data in the next 10 yr are outlined, from understanding drivers of biodiversity across spatial and temporal scales to defining complex feedback mechanisms in humanâenvironmental systems. Last, the essential elements needed to engage and support a diverse and inclusive NEON user community are highlighted: training resources and tools that are openly available, funding for broad community engagement initiatives, and a mechanism to share and advertise those opportunities. NEON users require both the skills to work with NEON data and the ecological or environmental science domain knowledge to understand and interpret them. This paper synthesizes early directions in the communityâs use of NEON data, and opportunities for the next 10 yr of NEON operations in emergent science themes, open science best practices, education and training, and community building
Ecological and behavioural traits of the Sri Lankan water monitor (Varanus salvator) in an urban landscape of Western Province, Sri Lanka
The Asian water monitor Varanus salvator is one of the largest species of lizard in the world and is widespread on the island of Sri Lanka. In the present study, we conducted a 7-month survey within a 5-km stretch in the urbanised Attanagalu-Oya river area to study habitat associations, mesohabitat use and behaviour of V. salvator in urban landscapes. The greatest number of monitor sightings was made in aquatic habitats, followed by terrestrial and arboreal habitats within the riparian zone. Sightings of different life history stages of V. salvator across major habitat types varied significantly. The adults and subadults associated mostly with aquatic and terrestrial habitats, whereas hatchlings and juveniles associated mostly with aquatic and arboreal habitats. Given variable sighting frequencies of distinct life history stages across different major habitat types, it is likely that there is substantial age-structured niche partitioning in V. salvator. The urban population of V. salvator studied seemed to be fairly abundant, and resilient to anthropogenic stressors and adversity of urbanisation. In species-depauperate urban environments, ecosystem functions provisioned by V. salvator as generalist predators as well as scavengers are arguably significant and deserve further investigation. No direct anthropogenic threats were observed during the study
Recommended from our members
Expanding NEON biodiversity surveys with new instrumentation and machine learning approaches
A core goal of the National Ecological Observatory Network (NEON) is to measure changes in biodiversity across the 30-yr horizon of the network. In contrast to NEONâs extensive use of automated instruments to collect environmental data, NEONâs biodiversity surveys are almost entirely conducted using traditional human-centric field methods. We believe that the combination of instrumentation for remote data collection and machine learning models to process such data represents an important opportunity for NEON to expand the scope, scale, and usability of its biodiversity data collection while potentially reducing long-term costs. In this manuscript, we first review the current status of instrument-based biodiversity surveys within the NEON project and previous research at the intersection of biodiversity, instrumentation, and machine learning at NEON sites. We then survey methods that have been developed at other locations but could potentially be employed at NEON sites in future. Finally, we expand on these ideas in five case studies that we believe suggest particularly fruitful future paths for automated biodiversity measurement at NEON sites: acoustic recorders for sound-producing taxa, camera traps for medium and large mammals, hydroacoustic and remote imagery for aquatic diversity, expanded remote and ground-based measurements for plant biodiversity, and laboratory-based imaging for physical specimens and samples in the NEON biorepository. Through its data science-literate staff and user community, NEON has a unique role to play in supporting the growth of such automated biodiversity survey methods, as well as demonstrating their ability to help answer key ecological questions that cannot be answered at the more limited spatiotemporal scales of human-driven surveys. © 2021 The Authors.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Multi-Decadal Forest-Cover Dynamics in the Tropical Realm: Past Trends and Policy Insights for Forest Conservation in Dry Zone of Sri Lanka
Situating and Sequencing Quagmire: The Role of Simulation-Based Gaming in Preparing Students for Future Learning at Capitol Reef National Park, Utah
Multi-Decadal Forest-Cover Dynamics in the Tropical Realm: Past Trends and Policy Insights for Forest Conservation in Dry Zone of Sri Lanka
Urbanisation generates multiple trait syndromes for terrestrial animal taxa worldwide
Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats, species, and functional groups. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities. Using a dataset encompassing six terrestrial faunal taxa (amphibians, bats, bees, birds, carabid beetles and reptiles) across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy showing the strongest response. Our findings suggest that urbanisation results in four trait syndromes (mobile generalists, site specialists, central place foragers, and mobile specialists), with resources associated with reproduction and diet likely driving patterns in traits associated with mobility and body size. Functional diversity measures showed varied responses, leading to shifts in trait space likely driven by critical resource distribution and abundance, and taxon-specific trait syndromes. Maximising opportunities to support taxa with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation and helps ensure that urban environments have the capacity to respond to future challenges. These actions are critical to reframe the role of cities in global biodiversity loss