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    Taking climate change effects on benthos into account in CCAMLR

    Request Meeting Document
    Document Number:
    WS-CC-2023/15
    Author(s):
    Cummings, V., D. Lohrer et al.
    Submitted By:
    Mr Nathan Walker (New Zealand)
    Approved By:
    Mr Nathan Walker (New Zealand)
    Abstract

    Polar seafloor ecosystems are changing rapidly and dramatically, challenging previously held paradigms of extreme dynamical stability. Warming-related declines in polar sea ice are expected to alter fluxes of phytoplankton and under-ice algae to the seafloor. Coastal Antarctic regions are biodiverse and productive regions, covered in sea ice for much of the year. This land-fast sea ice is a platform for life (e.g. penguins, seals, microbial communities, larval stages of invertebrates and fish) and controls sea surface light conditions that are crucial for primary productivity.  Amongst the under-sea ice associated species are early life stages of silverfish – known to be a key prey species for toothfish and Adelie penguins. Also key is the sea ice microalgae which provides food to pelagic organism as well as the benthos on the seafloor below. Studies of high latitude Ross Sea benthic communities indicate the sensitivity of the benthos to changes in sea ice conditions, and shed light on Antarctic marine trophic cascades and trajectories of response of iconic high-latitude seafloor habitats to a warming climate. They emphasise the need for biological information to be paired with environmental data longer term in order to detect, interpret and manage the responses of benthic communities, habitats and their higher trophic predators to anthropogenic impacts.