17 research outputs found

    Quantitative fatty acid signature analysis reveals a high level of dietary specialization in killer whales across the North Atlantic

    Get PDF
    Quantifying the diet composition of apex marine predators such as killer whales (Orcinus orca) is critical to assessing their food web impacts. Yet, with few exceptions, the feeding ecology of these apex predators remains poorly understood. Here, we use our newly validated quantitative fatty acid signature analysis (QFASA) approach on nearly 200 killer whales and over 900 potential prey to model their diets across the 5000 km span of the North Atlantic. Diet estimates show that killer whales mainly consume other whales in the western North Atlantic (Canadian Arctic, Eastern Canada), seals in the mid-North Atlantic (Greenland), and fish in the eastern North Atlantic (Iceland, Faroe Islands, Norway). Nonetheless, diet estimates also varied widely among individuals within most regions. This level of inter-individual feeding variation should be considered for future ecological studies focusing on killer whales in the North Atlantic and other oceans. These estimates reveal remarkable population- and individual-level variation in the trophic ecology of these killer whales, which can help to assess how their predation impacts community and ecosystem dynamics in changing North Atlantic marine ecosystems. This new approach provides researchers with an invaluable tool to study the feeding ecology of oceanic top predators

    Nanoindentation in polymer nanocomposites

    Full text link

    Asymptotic behavior of solutions of a third order nonlinear differential equation

    No full text
    The asymptotic properties of solutions of some third order differential equation are examined. Sufficient conditions for the square integrability and oscillation of solutions are established.Вивчаються асимптотичнi властивостi розв’язкiв деякого рiвняння третього порядку. Встановлено достатнi умови квадратичної iнтегровностi та осциляцiйностi розв’язкiв

    Stability and square integrability of derivatives of solutions of nonlinear fourth order differential equations with delay

    No full text
    Abstract In this paper, we give sufficient conditions for the boundedness, uniform asymptotic stability and square integrability of the solutions to a certain fourth order non-autonomous differential equations with delay by using Lyapunov’s second method. The results obtained essentially improve, include and complement the results in the literature
    corecore