Predator control of marine communities increases with temperature across 115 degrees of latitude.

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.

Fouling assemblage of marine debris collected in a temperate South-western Atlantic coastal lagoon: A first report.

In the South-western Atlantic, studies dealing with the impacts of debris on marine species are focused mainly on vertebrates, being scarce the studies conducted to determine the association of fouling species to marine debris. A total of 33 marine debris items with fouling specimens were collected in Mar Chiquita coastal lagoon, Argentina. Species richness varied between one and five species per debris item, and dominant species included the barnacle Amphibalanus improvisus (93.94%), followed by the bryozoan Membranipora sp. (72.73%), undetermined polychaetes (36.36%), the mollusc Ostrea sp. (15.15%), the hydrozoan Amphisbetia operculata and the mollusc Brachidontes rodriguezii (3.45%, in both cases). We concluded that marine debris constitutes a suitable settlement site for sessile species inhabiting the lagoon, where hard-substratum are absent; while buoyancy analysis suggested that the initial colonization occurred both on marine debris suspended in the water column or at the sea surface, and in those laying on the seafloor.