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Ocean acidification (OA), the reduction of ocean pH due to hydration of atmospheric C[O.sub.2], is known to affect growth and survival of marine invertebrate larvae. Survival and transport of vulnerable planktonic larval stages play important roles in determining population dynamics and community structures in coastal ecosystems. Here, we show that larvae of the purple urchin, Strongylocentrotus purpuratus, underwent high-frequency budding (release of blastula-like particles) when exposed to elevated pC[O.sub.2] level (> 700 µatm). Budding was observed in > 50% of the population and was synchronized over short periods of time (~ 24 h), suggesting this phenomenon may be previously overlooked. Although budding can be a mechanism through which larval echinoids asexually reproduce, here, the released buds did not develop into viable clones. OA-induced budding and the associated reduction in larval size suggest new hypotheses regarding physiological and ecological tradeoffs between short-term benefits (e.g. metabolic savings and predation escape) and long-term costs (e.g. tissue loss and delayed development) in the face of climate change., Introduction Anthropogenic carbon dioxide concentration in the atmosphere (pC[O.sub.2]) has been rising and is expected to increase to 700 ppm by 2100 (Sabine et al. 2004). The world's oceans represent [...]

Climate models predict that the average temperature in the North Sea could increase 3-5°C and surface-waters pH could decrease 0.3-0.5 pH units by the end of this century. Consequently, we investigated the combined effect of decreased pH (control pH 8.1; decreased pH 7.6) and temperature (control 6.7°C; elevated 9.5°C) on the hatching timing and success, and the zoeal development, survival, feeding, respiration and growth (up to stage IV zoea) of the northern shrimp, Pandalus borealis. At elevated temperature, embryos hatched 3 days earlier, but experienced 2-4% reduced survival. Larvae developed 9 days faster until stage IV zoea under elevated temperature and exhibited an increase in metabolic rates (ca 20%) and an increase in feeding rates (ca 15-20%). Decreased pH increased the development time, but only at the low temperature. We conclude that warming will likely exert a greater effect on shrimp larval development than ocean acidification manifesting itself as accelerated developmental rates with greater maintenance costs and decreased recruitment in terms of number and size., Introduction Ocean acidification (OA) has been shown to alter calcification, metabolism and the developmental trajectories and survival of marine invertebrates (Doney et al. 2009; Byrne 2011; Byrne 2012). As development, [...]