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Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community composition at such geographic scales remains unknown. Using standardized experiments that spanned 115° of latitude, at 36 nearshore sites along both coasts of the Americas, we found that marine predators have both higher consumption rates and consistently stronger impacts on biomass and species composition of marine invertebrate communities in warmer tropical waters, likely owing to fish predators. Our results provide robust support for a temperature-dependent gradient in interaction strength and have potential implications for how marine ecosystems will respond to ocean warming.

We present a case study of the potential impact on hurricane storm surge due to deepening the Corpus Christi Ship Channel through Aransas Pass in the region of Corpus Christi and Port Aransas, Texas. Our investigation is based on numerical mathematical models of the circulation of coastal water due to Hurricane Harvey and two synthetic hurricanes derived from Harvey. From the models, we ascertain maximum storm surge as well as elevation time series at critical locations in the study region. To assess the effects of a deeper channel, we compare the model outputs for current and proposed future channels. The models indicate that the changes to maximum storm surge magnitude are small and in large portions of the study area the models indicate a reduction in surge magnitude. However, there are some local areas where the models results show an increase of up to 15 centimeters.

The horizontal swimming patterns of groups of Acartia hudsonica were tracked and described using a video-computer system. The patterns were compared in the presence of clones of bioluminescent and nonbioluminescent Protogonyaulax tamarensis. Bioluminescent dinoflagellates increased the number of high-speed swimming bursts by the copepods and thus decreased the amount of slow-speed swimming characteristic of their grazing behavior. With bioluminescent dinoflagellates, swimming paths were less circuitous and swimming speeds higher. This behavior may tend to move copepods away from bioluminescent dinoflagellates in nature. Both changes in swimming behavior should result in reduced grazing by the copepods on bioluminescent dinoflagellates.