512,839 research outputs found

    Connectivity between coastal habitats of two oceanic Caribbean islands as inferred from ontogenetic shifts by coral reef fishes

    Get PDF
    Mangroves and seagrass beds are considered important nursery habitats for juveniles of coral reef fishes. Studies have mostly focused on the fish community of just one habitat, so the connectivity between different coastal habitats is often unclear. In this study, density and size of reef fish were determined using a single sampling technique in four non-estuarine bay habitats and four reef zones in Curaçao and Bonaire (Netherlands Antilles). The data indicate that of the complete reef fish community at least 21 species show ontogenetic crossshelf shifts in habitat utilization. The 21 species mainly utilized shallow-water habitats (mangroves, seagrass beds, channel and shallow reef) as nursery habitats and the deeper coral reef zones (\u3e 5 m depth) as adult lifestage habitats. Fish species utilized 1–3 different nursery habitats simultaneously, but habitat utilization clearly differed between species. Previous studies showed that the dependence on these nursery habitats is very high, based on reduced density or absence of adults on coral reefs where these habitats were absent. The strong connectivity between several coastal habitats during the ontogeny of various commercially important reef fish species is evidence for the inclusion of bay habitats within boundaries of fishery reserves or marine protected areas

    Mesoscopic structure and social aspects of human mobility

    Get PDF
    The individual movements of large numbers of people are important in many contexts, from urban planning to disease spreading. Datasets that capture human mobility are now available and many interesting features have been discovered, including the ultra-slow spatial growth of individual mobility. However, the detailed substructures and spatiotemporal flows of mobility - the sets and sequences of visited locations - have not been well studied. We show that individual mobility is dominated by small groups of frequently visited, dynamically close locations, forming primary "habitats" capturing typical daily activity, along with subsidiary habitats representing additional travel. These habitats do not correspond to typical contexts such as home or work. The temporal evolution of mobility within habitats, which constitutes most motion, is universal across habitats and exhibits scaling patterns both distinct from all previous observations and unpredicted by current models. The delay to enter subsidiary habitats is a primary factor in the spatiotemporal growth of human travel. Interestingly, habitats correlate with non-mobility dynamics such as communication activity, implying that habitats may influence processes such as information spreading and revealing new connections between human mobility and social networks.Comment: 7 pages, 5 figures (main text); 11 pages, 9 figures, 1 table (supporting information

    Implications of climate change for coastal and inter-tidal habitats in the UK

    Get PDF
    Coastal habitats are diverse and vary in the extent to which they are shaped by physiographic processes, such as wave action, wind, tides and sediment availability, and the relative influence of terrestrial and marine environments, e.g. tidal inundation versus groundwater levels. Coastal systems usually comprise mosaics of habitats that are functionally interdependent: for instance, saltmarsh may form behind a barrier island or shingle ridge that itself may also support a dune system; or estuaries may include a range of habitats that ultimately depend on sediment supply from the catchment and the mixing of fresh and saline waters. Coastal grazing marsh is a man-made, largely freshwater habitat, occurring landward of intertidal and coastal habitats and protected from them by natural or man-made structures. Whilst grazing marsh and other coastal habitats are not strictly functionally interdependent, there are significant conflicts between protecting grazing marsh and allowing landward movement of coastal habitats

    Habitat Associations of Macro-Staphylinids (Coleoptera: Staphylinidae) at Alice L. Kibbe Life Science Station, Hancock County, Illinois

    Get PDF
    Habitat associations of size-selected (≥ 5 mm length) rove beetles (Coleoptera: Staphylinidae), hereafter referred to as “macro-staphylinids,” were studied in west-central Illinois forest and prairie habitats in 2005 using pitfall traps. Habitats sampled included oak-hickory forest last burned in spring 2004, oak-hickory forest burned in spring 2005, oak-hickory forest unburned for 5+ years, unburned early successional forest, reconstructed prairie last burned in spring 2004, and reconstructed prairie burned in spring 2005. A total of 361 macrostaphylinids, representing 12 species, were collected, with Philonthus caerulipennis (Mannerheim), Platydracus maculosus (Gravenhorst), Platydracus fossator Gravenhorst, Platydracus zonatus (Gravenhorst), and Tachinus fimbriatus Gravenhorst comprising 94% of all macro-staphylinids collected. Fewest numbers of macro-staphylinids were collected in prairie habitats, particularly the prairie burned in spring 2005. A multi-response permutation procedure revealed significant variation in species composition among habitats, with relatively large differences between burned and unburned forest habitats and between forest and prairie habitats. Within-habitat variation in species composition was relatively high in the prairie and recently burned forest habitats. Indicator species analysis revealed a significant association of Philonthus asper Horn with the early successional forest, and four species had relatively high indicator values for multiple forest habitats, with fire playing a potentially important role in some cases. More intensive sampling and larger sample sizes are needed to clarify these potential habitat associations

    The Farmland Wildlife Survey – raising awareness of wildlife habitats

    Get PDF
    End of project reportThe Farmland Wildlife Survey involved a short visit (about 3 hours) to 19 REPS demonstration farms, and an identification of habitats and wildlife on each farm, with an emphasis on common farmland habitats such as hedgerows, ponds, watercourses, field margins, woodland, plant species and other areas of wildlife value. The survey results were provided to the farmer and Teagasc REPS advisor as a report with colour pictures of representative habitats, and an explanation of why these habitats were important for wildlife.The Heritage Council

    Adaptations of lowland jungle mosses to anthropogenic environments in Guyana

    Get PDF
    Sixteen lowland jungle mosses growing in anthropogenic habitats at Santa and The Bell - Ituni localities on the Demerara River in Guyana were examined in detail with the aim of detecting any features which would indicate their adaptations to new habitats. Amounts of chlorophyll in leaf cells, protective coloration, alterations in leaf morphology, characteristics of old stems, rhizoid tomentum and fertility are considered as the most pronounced adaptive features of these species to new localities. The ecology, general appearance and morpho-anatomical changes of specimens from anthropogenic habitats were observed and compared with their equivalents from habitats occurring in the closest natural environments. No one species grows or has local centers of occurrence only in anthropogenic habitats. Generally, invasion of lowland jungle mosses into anthropogenic environments is considered as difficult, slow and limited

    Issues related to the classification of Mediterranean temporary wet habitats according with the European Union Habitats Directive

    Get PDF
    From a biological and biogeographic point of view, Mediterranean temporary wet habitats are recognised to be amongst the most interesting habitats in the Mediterranean bioclimatic region. They are considered to be habitats of Community Interest and are included in the “standing water group”. Due to an overlap in the plant species and syntaxa indicated as characteristic, the assignment of the plant communities to the habitats 3120, 3130 and 3170* is far from straightforward. We propose that the Isoetion communities be assigned to habitat 3170*, the Preslion cervinae, Cicendio-Solenopsion and Agrostion pourretii communities to habitat 3120, and the Cyperetalia fusci and Littorelletea uniflorae communities to habitat 3130

    Science-based restoration monitoring of coastal habitats, Volume Two: Tools for monitoring coastal habitats

    Get PDF
    Healthy coastal habitats are not only important ecologically; they also support healthy coastal communities and improve the quality of people’s lives. Despite their many benefits and values, coastal habitats have been systematically modified, degraded, and destroyed throughout the United States and its protectorates beginning with European colonization in the 1600’s (Dahl 1990). As a result, many coastal habitats around the United States are in desperate need of restoration. The monitoring of restoration projects, the focus of this document, is necessary to ensure that restoration efforts are successful, to further the science, and to increase the efficiency of future restoration efforts

    Woody and arboreal habitats of the Green Salamander (Aneides aeneus) in the Blue Ridge Mountains

    Get PDF
    The green salamander (Aneides aeneus) is primarily considered a rock crevice dwelling species. However, many early observations from Kentucky, Tennessee, Virginia, and West Virginia report A. aeneus taken from woody and arboreal habitats. There have been only four published records of A. aeneus using such habitats within the Blue Ridge Disjunct population of southwest North Carolina, northeast Georgia, and northwest South Carolina, and no records since 1952. Here I report two personal observations of A. aeneus using arboreal habitats in North Carolina. Additionally, I report nine observations, made by others, of A. aeneus using woody, arboreal, or otherwise non-rock-crevice habitats in North and South Carolina, including the first non-rock-crevice A. aeneus nesting record for the Blue Ridge. I also speculate that woody and arboreal habitats play a much larger role in the life-history of A. aeneus than generally thought, and that the rarity of A. aeneus is linked to the loss of American Chestnut and old-growth forests
    corecore