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In this paper we assess long-term trends and habitat changes to understand the relationships between coastal beaver (Castor canadensis), salmon, shoreline alterations, large-scale dam removals and nearshore ecological restoration. From this work we conclude that the removal of two large scale dams in the Elwha River has benefited beaver use of the coastal zone through water quality changes that allow beaver to re-establish high-quality zones and the expansion of riparian zones that provide extensive new food resources to beaver. However, the lower river hydrodynamic processes continue to be disrupted by a 200-meter earthen dike installed by local government and landowners for flood protection in the Elwha coastal zone in the 1960’s. The dike acts as a driver of lower river geomorphology and has resulted in the formation of a large and persistent lateral bar along the lower river channel. Associated disrupted hydrodynamics are causing a critical coastal zone of the unimpounded lower river side channels to fill in. This channel habitat has decreased by 23%, with an annual average shrinkage rate of 13%, from pre-dam removal size, resulting in a decrease in both quality and quantity of nursery function for juvenile wild fish in a coastal zone that was historically documented to be the highest functioning for endangered juvenile salmon and trout. Inversely, physical changes including improved water quality in the adjacent impounded west side channel and continued expansion of riparian vegetation along the west delta lateral bar benefitted coastal beaver that recolonized the west delta after dam removals. The newly colonized coastal beaver may provide ecological engineering services to offset side channel loss as well as promote continued fish access. However recreational use was found to negatively impact beaver use of the area. We therefore recommend a series of additional ecosystem restoration actions that incorporate beaver as an ecosystem restoration component of the coastal zone. These actions include a public outreach program to encourage passive recreation measures to prevent negative impacts to beaver, and legacy, ecosystem scale restoration projects that reconnect the hydrodynamics of the west delta to complete Elwha ecosystem restoration. Together, these steps, if implemented, will result in a synergistic ecosystem restoration throughout the watershed to the benefit of the coastal ecosystem, including both beaver and salmon, as intended by the large-scale dam removal project.

Separation and quantification of lupeol, stigmasterol and swertiamarin in ethanolic extracts of selected Cyathea species have been developed using HPTLC and an attempt is made to explore the biopotential of phytochemicals against various proteins by computational analysis. Compounds were separated using the specific mobile phase and the developed plates were sprayed with respective spraying reagents. The 3D structure of the receptor proteins viz., 1VSN, 5BNQ, 6HN8, 7DN4 and 3TJU, and the 3D SDF structures of ligands like lupeol, stigmasterol and swertiamarin were retrieved from the Protein Data Bank (PDB) and NCBI-Pub Chem Compound database respectively. The Argus 4.0.1 is computer generated drug design screening software is employed to analyze the binding affinity of test compounds against the selected proteins in the form of E-values versus potential drug targets. The docking result was saved and visualized using Discovery Studio Visualizer. The terpenoid band with Rf value 0.79 depicted the presence of lupeol in C. gigantea (0.04%) and C. crinita (0.02%). The steroid band with Rf value 0.41 confirmed the presence of stigmasterol with varied frequency viz., C. nilgirensis (0.33%), C. gigantea (0.29%) and C. crinita (0.52%). Lupeol, stigmasterol and swertiamarin showed the interaction against the studied proteins viz., 1VSN, 5BNQ, 6HN8, 7DN4, 3TJU with varied energy values and interacting residues. The results of the virtual screening and molecular docking analysis suggest that the phytochemical compounds of Cyathea species viz., lupeol and stigmasterol were identified as possible lead molecules to fight against cancer and cytotoxicity.

The Southwest Australian Floristic Region (SWAFR) is a global biodiversity hotspot with high plant diversity and endemism and a broad range of threatening processes. An outcome of this is a high proportion of rare and threatened plant species. Ongoing discovery and taxonomic description of new species, many of which are rare, increases the challenges for recovery of threatened species and prioritisation of conservation actions. Current conservation of this diverse flora is based on integrated and scientific evidence-based management. Here we present an overview of current approaches to the conservation of threatened flora in the SWAFR with a focus on active management through recovery and restoration that is integrated with targeted research. Key threats include disease, fragmentation, invasive weeds, altered fire regimes, grazing, altered hydro-ecology and climate change. We highlight the integrated approach to management of threats and recovery of species with four case studies of threatened flora recovery projects that illustrate the breadth of interventions ranging from In situ management to conservation reintroductions and restoration of threatened species habitats. Our review and case studies emphasise that despite the scale of the challenge, a scientific understanding of threats and their impacts enables effective conservation actions to arrest decline and enhance recovery of threatened species and habitats. Keywords: Threatened species, Threatening processes, Conservation, Recovery, Restoration, Biodiversity hotspot

Shaffer, J.A.; Oxborrow, B.; Parks, D.S.; Maucieri, D.G., and Michel, J., 2025. Linking marine ecosystem response to shoreline armor removal and large dam removals in the Elwha River and nearshore, Washington, USA. Journal of Coastal Research, 41(1), 1–15. Charlotte (North Carolina), ISSN 0749-0208. Large in-river dams and shoreline armor have a significant negative effect on coastal hydrodynamic and ecosystem processes. Armor removal (AR) is a well-documented shoreline restoration tool, and removal of large dams is proving to be an extremely effective tool to restore riverine ecosystem processes. However, nearshore ecosystem restoration associated with dam removals (DRs) is incomplete when shoreline impediments, including shoreline armoring and lower river alterations, remain, and linkages between dam and shoreline ARs are not well understood. In this study, nearshore ecosystem processes and function restoration response to large DRs and shoreline AR are assessed. Two nearly century-old large dams in the Elwha River watershed in the NW United States were removed during 2011–14, which liberated upward of 18 million tonnes (Mt) or approximately ∼9 million m3 of silt, sand, and gravel to sediment-starved, armored, and unarmored shorelines. Within 1 year of the initiation of DR, unarmored shorelines in the drift cell broadened, flattened, sediment fined, and large woody debris (LWD) volumes significantly increased. Armored shorelines continued to be steep and coarse grained. In 2016–17, approximately 4700 m3 of large riprap (shoreline armor) was removed from more than 650 m of the armored Elwha River east delta reach drift cell. Following AR, previously eroding shorelines broadened, sediment fined, LWD volumes increased significantly, and beach wrack metrics resembled non-armored beaches. These changes followed AR and did not occur at unarmored DR or control treatments. Invertebrate communities also responded to dam and armor removal (DAR) and showed increasing trends every year for 3 years after the project. It is concluded that only partial nearshore ecosystem restoration occurs from large DR when shoreline armoring that impairs nearshore hydrodynamic processes remains and that full ecosystem restoration of the nearshore associated with large DRs is obtained by restoring impaired shorelines along with DRs. [ABSTRACT FROM AUTHOR]

Introduction: In human-robot interaction (HRI), understanding human intent is crucial for robots to perform tasks that align with user preferences. Traditional methods that aim to modify robot trajectories based on language corrections often require extensive training to generalize across diverse objects, initial trajectories, and scenarios. This work presents ExTraCT, a modular framework designed to modify robot trajectories (and behaviour) using natural language input. Methods: Unlike traditional end-to-end learning approaches, ExTraCT separates language understanding from trajectory modification, allowing robots to adapt language corrections to new tasks-including those with complex motions like scooping-as well as various initial trajectories and object configurations without additional end-to-end training. ExTraCT leverages Large Language Models (LLMs) to semantically match language corrections to predefined trajectory modification functions, allowing the robot to make necessary adjustments to its path. This modular approach overcomes the limitations of pre-trained datasets and offers versatility across various applications. Results: Comprehensive user studies conducted in simulation and with a physical robot arm demonstrated that ExTraCT s trajectory corrections are more accurate and preferred by users in 80% of cases compared to the baseline. Discussion: ExTraCT offers a more explainable approach to understanding language corrections, which could facilitate learning human preferences. We also demonstrated the adaptability and effectiveness of ExTraCT in a complex scenarios like assistive feeding, presenting it as a versatile solution across various HRI applications. [ABSTRACT FROM AUTHOR]

A set S ⊆ V (G) is a geodetic vertex cover of G if S is both a geodetic set and a vertex cover of G. The minimum cardinality of a geodetic vertex cover of G is defined as the geodetic vertex covering number of G and is denoted by gα(G). A geodetic vertex cover S in a connected graph G is called aminimal geodetic vertex cover of G if no proper subset of S is a geodetic vertex cover of G. The upper geodetic vertex covering number g+α (G) of G is the maximum cardinality of a minimal geodetic vertex cover of G. Some general properties satisfied by the upper geodetic vertex covering number of a graph are studied. The upper geodetic vertex covering number of several classes of graphs are determined. Some bounds for g+α (G) are obtained and the graphs attaining these bounds are characterized. [ABSTRACT FROM AUTHOR]

The golden-backed tree-rat (Mesembriomys macrurus) is a large semi-arboreal rodent that has suffered a significant reduction in range since European settlement. Seven (three male, four female) founding adults for a captive colony were captured on the Mitchell Plateau, Western Australia, and transferred to Alice Springs, Northern Territory. The reproduction, growth, development and behaviour of M. macrurus in captivity were recorded. Twenty-three litters were born with litter size of 1–3 (median litter size: 2; overall sex ratio parity). There was no apparent seasonality in breeding. Oestrous cycle (9.9 ± 0.4 days) and gestation (46.8 ± 2.8 days) were estimated from known births and birth dates determined from calculated growth curves. Mean weight at birth was 17.2 g (±1.3, n = 12) and growth of the young was rapid, with head length reaching the asymptote from 54 days and head-body length from 83 days. Young were weaned at about 40 days and adult pelage complete by 98 days. Reproductive maturity occurred from 5 to 6 months for females and in males testes became scrotal from 76 days. Developmental stages and captive behaviour were also recorded. These results are compared with reproduction and growth of the closely related black-footed tree-rat (M. gouldii) and brush-tailed rabbit-rat (Conilurus penicillatus). The golden-backed tree-rat, a large native rodent from tropical Western Australia and Northern Territory, was once abundant and widespread, but numbers have declined greatly. Its conservation depends on knowing its ecology and breeding biology, and in this study we provide the first details of the breeding biology of this tree-rat. This information is essential for developing conservation strategies to ensure the survival of this unique Australian species. Photograph by Euan Ritchie. [ABSTRACT FROM AUTHOR]

Context: Distribution and abundance of the three northern Australian tree-rat species, Conilurus penicillatus , Mesembriomys macrurus and M. gouldii , have contracted significantly since European settlement. All three species were recorded from the Mitchell Plateau, Western Australia, in the 1980s, enabling their niche separation to be assessed. Despite this study being conducted in 1987, the results remain relevant for conservation strategies for these species. Aims: To determine the ecological separation among three tropical tree-rat species by documenting habitat preferences, habitat use and diet. Methods: Live-trapping, radiotracking and spotlighting were used to assess relative abundance, habitat preference and movements of each species at nine sites on the Mitchell Plateau. Diet was determined using scat analysis; vegetation communities were described and characterised by pattern analysis. Key results: C. penicillatus (number of individuals trapped (n) = 24) was most abundant, followed by M. macrurus (n = 8) and M. gouldii (n = 2). Mature open forest with a well-developed understorey was preferred by the predominantly arboreal M. gouldii (1 site), M. macrurus occupied more varied habitats (four sites), especially ecotones between vine thicket and open eucalypt forest and the boulder edges of the plateau, and C. penicillatus occupied the greatest variety of habitats (four sites) in open eucalypt woodland with a diverse shrub layer and ground cover almost absent to very dense, tall grass. Diet analysis identified M. gouldii as a frugivore (fruits, some flowers), M. macrurus as an omnivore (seeds, fruits, flowers, termites, other invertebrates), and C. penicillatus as a generalist (monocot and dicot leaves, seeds, flowers, fruits, some arthropods). Conclusions: The largest of the species, M. gouldii , appeared to have the narrowest ecological niche, preferring more stable, structurally diverse, mature open forest that is infrequently burnt. The mid-sized M. macrurus occupies a broader range of habitats, particularly ecotones between vine thickets and eucalypt forest/woodland and woodland. C. penicillatus preferred open eucalypt woodland with a variable understorey. Implications: With a changing climate, increased fire frequency, habitat degradation by introduced herbivores and predation by cats across the tropical savanna distribution of these threatened tree-rats, this study provides data to underpin actions that may ensure their survival. The distribution and abundance of the three tropical tree-rat species have contracted since European settlement and characterisation of their ecological niche is critical for their conservation. The habitat preferences, habitat use and diet of each species on the Mitchell Plateau, Western Australia, were determined and compared. Despite overlap in habitat and diet preferences, each species is filling a distinct niche. Photograph by Euan Ritchie. [ABSTRACT FROM AUTHOR]