Impacts of ocean acidification on hermit crab communities through contrasting responses of Pagurus filholi (de Man, 1887) and Clibanarius virescens (Krauss, 1843)

Decreased Diversity and Abundance of Marine Invertebrates at CO2 Seeps in Warm-Temperate Japan

“…1). Agostini et al (2018), Harvey et al (2019), andTomatsuri and describe the methods used for measuring pH, temperature, salinity and total alkalinity and associated environmental factors at our study sites through in situ measurements and/or dis- Agostini et al, 2018, Harvey et al, 2019, andthis study (stars) plus other sites that we surveyed less frequently (diamonds and circles). Blue symbols show sites with ambient low levels of pCO2 in seawater, red symbols show sites with high levels of pCO2 in seawater.…”

“…In both cases, 10-15 replicate quadrats were deployed at least a metre apart on steeply sloping rock faces at nine ambient sites and three high CO2 sites. Tomatsuri and Kon (2019) surveyed the diversity and abundance of hermit crabs and live molluscs at three ambient sites and two high CO2 sites using ten 50 × 50 cm quadrats per site when the tide was out. Their previously unpublished live mollusc data are included here.…”

“…The present paper provides a checklist of benthic macroinvertebrate diversity around warm-temperate CO2 seeps off Shikine Island. This list reflects the authors' collective zoological knowledge of the area and draws extensively on surveys by Agostini et al (2018), Harvey et al (2019) and Tomatsuri and Kon (2019). Here, we assess how the diversity, abundance, and function of macrobenthic fauna change from ambient to high CO2 areas.…”

“…Seawater pCO2, dissolved inorganic carbon and the saturation states for calcite (Ωcalcite) and aragonite (Ωaragonite) are mean values ( ± SD) calculated using the carbonate chemistry system analysis program CO2SYS. Shikine Island hydrothermal seeps were reported in detail by Agostini et al (2018), Harvey et al (2019) and Tomatsuri and Kon (2019) and are synthesised here in Table 1. In brief, whilst there were no significant differences in salinity or total alkalinity between sites, the mean values of seawater pH fell from ≥ 8.0 in ambient conditions to ≤ 7.8 near the seeps.…”

“…This caused a loss in habitat complexity and a reduction in filter feeding and grazing functions , which amount to a loss in ecosystem services such as shellfish productivity and maintenance of good water quality (Lemasson et al, 2017). The diversity and abundance of shells available to hermit crabs and the abundance of these crabs were all significantly reduced at high CO2 (Tomatsuri and Kon, 2019). An increased abundance of anemones in acidified conditions ties in with similar observations in the Mediterranean and may relate to a decrease in competition with calcareous animals for living space (Suggett et al, 2012).…”