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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 [...]

The National Science Education Standards have highlighted the importance of active learning and reflection for contemporary scientific methods in K-12 classrooms, including the use of models. Computer modeling and visualization are tools that researchers employ in their scientific inquiry process, and often computer models are used in collaborative projects across disciplines. The goal of this project was to develop and field-test a module that used a computer model to teach marine sciences content in an applied, inquiry-based, and collaborative manner. Students used an estuarine transport model to explore the question of how circulation patterns affect planktonic organisms, demonstrating the interdisciplinary interaction of physics and biology. Our experience suggests that computer models, when used for inquiry, can help foster students' understanding of the nature of science and critical-thinking skills. Key Words: Interdisciplinary lesson; environmental science; estuarine transport; STEM., Project Motivation Calls from the National Research Council (1996) and National Science Foundation (2000) emphasized the importance of providing students with authentic science experiences through active inquiry. They also highlighted [...]

Many Antarctic seabirds depend on prey that are patchy, cryptic, ephemeral, and unpredictable in location. These predators typically employ two alternative behavioral strategies for locating resource patches: direct visual or olfactory detection, and indirect detection (local enhancement) by sighting other predators that are already exploiting a patch. We developed a model of direct detection and local enhancement in seabirds that predicts how foraging success varies with behavioral strategy, seabird densities, and prey swarm density and detectability. Application of the model to Black-browed Albatrosses foraging for Antarctic krill near South Georgia suggests that local enhancement is generally a highly effective foraging strategy, and that the fraction of time albatrosses spend in feeding flocks should show strong interactions between prey and conspecific densities. To test these predictions, we analyzed survey data collected near South Georgia in January-March 1986. Our analysis suggests a strong Allee-type density dependence in foraging success that was qualitatively and quantitatively consistent with model predictions. This density dependence suggests a potential for destabilizing patterns of resource utilization and reproductive success in Black-browed Albatrosses that may have important implications for conservation of albatrosses and other Antarctic species. Key words: Allee effect; Antarctic krill: area-restricted search; Black-browed Albatross; density dependence; Euphausial superba; foraging model; foraging strategy; local enhancement; South Georgia; Thalassarche melanophris.

The functional consequences of the varied arm arrangements for larval swimming performance are studied using a hydromechanical model of idealized equal-armed larvae. It is observed that the vertical transport may affect diverse passively stable swimmers and not only the armed larvae.