Anthropogenic Marine Debris (AMD) in the SE Pacific has primarily local origins from land-based sources, including cities (coastal and inland), beach-goers, aquaculture, and fisheries. The low frequency of AMD colonized by oceanic biota (bryozoans, lepadid barnacles) suggests that most litter items from coastal waters of the Humboldt Current System (HCS) are pulled offshore into the South Pacific Subtropical Gyre (SPSG). The highest densities of floating micro-and macroplastics are reported from the SPSG. An extensive survey of photographic records, unpublished data, conference proceedings, and published studies revealed interactions with plastics for 97 species in the SE Pacific, including 20 species of fish, 5 sea turtles, 53 seabirds, and 19 marine mammals. Sea turtles are most affected by interactions with plastics, underlined by the fact that 4 of the 5 species suffer both from entanglement and ingestion. Reports gathered in this review suggest that interactions along the continental coast are mostly via entanglement. High frequencies of microplastic ingestion have been reported from planktivorous fish and seabirds inhabiting the oceanic waters and islands exposed to high densities of microplastics concentrated by oceanic currents in the SPSG. Our review also suggests that some species from the highly productive HCS face the risk of negative interactions with AMD, because food and plastic litter are concentrated in coastal front systems. In order to improve the conservation of marine vertebrates, especially of sea turtles, urgent measures of plastic reduction are needed.

The Easter Island Ecoregion is in the center of the South Pacific gyre and experiences ultra-oligotrophic conditions that could make it highly susceptible to global change and anthropogenic activities, so it is imperative that these regions are characterized and studied so that conservation and sustainable management strategies can be developed. From the few studies from the region, we know that the coastal areas are relatively depauperate and have relatively high rates of endemism. Here, we present a brief report from the first video observations from this region of the deep fish fauna from ROV exploration of benthic communities from 157 to 281 m and baited drop-camera videos from 150 to 1850 m. We observed a total of 55 fish species from the ROV and Drop-Cam surveys; nine could not be assigned family level or lower, 26 were observed in the ROV surveys, 29 were observed in the Drop-Cam surveys, nine were observed with both survey methods, at least six species are potentially new to science, and nine species were observed at deeper depths than previously reported. These new reports may be indicative of the unique oceanographic conditions in the area and the relative isolation of the communities that have provided opportunity for the evolution of new species and favorable conditions for range expansion. In contrast, these new reports may be indicative of the severe undersampling in the south Pacific at mesopelagic depths. The prevalence of potentially new species suggests that the region likely harbors a wealth of undiscovered biodiversity.

Egg capsules of Zearaja chilensis were obtained from individuals kept in captivity and from dead specimens captured in Valparaíso Bay, central Chile. One female under laboratory conditions deposited three pairs of egg capsules in 6 days. The egg capsules of Dipturus trachyderma were obtained from a female captured in Valdivia, south Chile. Fresh egg capsules of both species were golden-brown and thick walled. Size of egg capsules of Z. chilensis ranged from 94 to 144 mm in capsule length and 64 to 76 mm in capsule width. Those of D. trachyderma ranged between 197 and 199 mm in capsule length and 110.0 and 129.0 mm in capsule width. Range and mean values of capsule length and width of egg capsules described in this study were smaller than those reported for the same species in the south-western Atlantic Ocean. This is the first report on egg-laying rate of Z. chilensis and the first description of egg capsules of Z. chilensis and D. trachyderma from the south-eastern Pacific Ocean.

Reef fishes are an important component of marine biodiversity, and changes in the composition of the assemblage structure may indicate ecological, climatic, or anthropogenic disturbances. To examine spatial differences in the reef fish assemblage structure around Easter Island, eight sites were sampled during autumn and summer 2016–2017 with baited remote underwater video systems. To determine seasonal changes, quarterly (seasonal) sampling was conducted at five of those eight sites. Fifteen pelagic species of fishes were recorded during this study, some of which have not previously been recorded in scuba surveys, including the Galapagos shark (Carcharhinus galapagensis, Snodgrass & Heller, 1905) and tunas (Scrombidae). Significant spatial and seasonal differences were found in the fish assemblage. Fish assemblages from the south coast differed significantly from those along the west and east coasts, mainly due to the occurrence of top predators. Winter differed from other seasons, especially along the south coast where the island is more exposed to large oceanic swells and winds from Antarctica. Owing to the variety and high relative abundance of species recorded during this survey, baited remote underwater video systems seemed to be an effective method for studying top predators at Easter Island. The identification of priority zones for the protection of top predator species represents an important contribution of this study, in order to develop management and conservation strategies to be implemented in the newly created Rapa Nui multiple uses coastal marine protected areas.

On 20 December 2017, a mature Triaenodon obesus was observed at Hanga Roa Bay, Rapa Nui (Easter Island) at c.18 m depth. This observation increases both the range of T. obesus in the Pacific Ocean and the number of elasmobranch species at Rapa Nui. In combination with other recent sightings further extending the southern range of this species during the Austral summer, sea surface temperature is suggested as key to southern dispersal.

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1. Marine protected areas (MPAs) are becoming a widely used tool for the conservation of biodiversity and for fishery management; however, most of these areas are designed without prior knowledge of the basic ecological aspects of the species that they are trying to protect. 2. This study investigated the movement of two top predators: the Galapagos shark, Carcharhinus galapagensis, and the yellowtail amberjack, Seriola lalandi, in and around the Motu Motiro Hiva Marine Park (MMHMP) using MiniPAT satellite tags to determine the effectiveness of this MPA for the protection of these species. 3. The Galapagos sharks (n = 4) spent most of their tag deployment periods inside the MMHMP. However, high intraspecific variability was observed in their movement dynamics. Daily individual maximum movements ranged from 17 to 58 km and the maximum distance from Salas y Gómez Island, the only emergent island within the MMHMP, ranged from 31 to 139 km. 4. The maximum linear distance travelled for a female juvenile Galapagos shark (152 cm total length) was 236 km, which is greater than the maximum distance previously documented for juveniles of this species (<50 km). 5. For the yellowtail amberjack (n = 1), 91% of the satellite geolocations were within the MMHMP, with a maximum daily distance travelled of 6 km. The maximum

1. The structure of food webs provides important insight into biodiversity, organic matter (OM) pathways, and ecosystem functioning. 2. Stable isotope analysis (δ 13 C and δ 15 N) was used to characterize the trophic structure and the main OM pathways supporting food webs in the Rapa Nui