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For marine species with planktonic dispersal, invasion of open ocean coastlines is impaired by the physical adversity of ocean currents moving larvae downstream and offshore. The extent species are affected by physical adversity depends on interactions of the currents with larval life history traits such as planktonic duration, depth and seasonality. Ecologists have struggled to understand how these traits expose species to adverse ocean currents and affect their ability to persist when introduced to novel habitat. We use a high‐resolution global ocean model to isolate the role of ocean currents on the persistence of a larval‐producing species introduced to every open coastline of the world. We find physical adversity to invasion varies globally by several orders of magnitude. Larval duration is the most influential life history trait because increased duration prolongs species' exposure to ocean currents. Furthermore, variation of physical adversity with life history elucidates how trade‐offs between dispersal traits vary globally. [ABSTRACT FROM AUTHOR]

Although ecologists have speculated that sublethal predation can impact prey dynamics, consequences of these predator effects have seldom been experimentally tested. In soft-sediment marine communities, fishes crop extended feeding siphons of buried clams, potentially causing clams to reduce their burial depth, thereby enhancing their susceptibility to excavating lethal predators. We simulated cropping of the confamilial clams,Protothaca stamineaandVenerupis philippinarum, by removing the top 40% of siphons, which caused each species to burrow 33–50% shallower than conspecifics with intact siphons. To examine subsequent consequences of reduced burial depth, we exposed cropped and intact clams to natural levels of predation in the field. Because of a naturally longer siphon,Protothaca, even after cropping, remained at relatively safe burial depths. In contrast, siphon cropping nearly doubled the mortality rate ofVenerupis. Thus, while sublethal predation facilitates lethal predation, this linkage depends on specific life history characteristics, even among ecologically similar species. [ABSTRACT FROM AUTHOR]