Saltwater crocodiles (Crocodylus porosus) are known to leave their home range and to visit and eventually colonize offshore islands. Being good swimmers, coupled with an ability to go for a prolonged period without food, allows saltwater crocodiles to cover long open water voyages of 2000 km and more. Drawing on modern observations, historic data, and oral traditions, this paper compiles and critically examines all available evidence for vagrant crocodiles in the Pacific Ocean area. The modes of dispersal, as well as potential dispersal success, are discussed.

The vegetation composition and structure of “pristine” primary lowland rainforest in Waisoi, south Viti Levu, Fiji were assessed quantitatively by recording all trees with a diameter at breast height > 1 cm within sample plots covering the topographic range of the Waisoi area. The tree flora comprised 78 recognizable taxa, 68 of which were recorded to species. Of these 68 species, 61% were endemic. Four forest types were evaluated; “River Flat,” “Slope,” “Ridge,” and “Quasi-montane.” Differences in stem density, species richness, and diversity were observed across the forest types. The River Flat and Quasi-montane forest types were distinct from each other and from Slope and Ridge forests. Canopy structure was characterized for each of these forest types and illustrated with profile diagrams.

Determining the diet of arthropods can be difficult due to their small size and complex food webs, especially in Hawai‘i, where knowledge of arthropod predator–prey interactions is sparse. The diet of the Hawai‘i Island-endemic carabid beetle, Blackburnia hawaiiensis Sharp (Coleoptera: Carabidae) is of particular interest because of its peculiar arboreal behavior and metathoracic flight wings. Our study objective was to determine the diet of B. hawaiiensis in replicated, geographically separated locations by using two different yet complementary laboratory techniques: natural abundance stable isotope analysis (SIA) and high-throughput sequencing (HTS). Overall, B. hawaiiensis had a greater average δ¹⁵N and similar δ¹³C compared to the other arthropods sampled in this study and HTS data revealed Diptera and Lepidoptera sequences in the beetle's gut contents. These results are consistent with B. hawaiiensis being classified as a generalist predator. The combination of SIA and HTS are important methods for determining the diet of species within complex food webs, particularly for species that are difficult to observe in nature.

A new hydromedusa has been discovered off the coast of Tahiti in the waters of French Polynesia. The species belongs to the genus Eutiara, which prior to this study included two valid species. The third species described in this paper can be differentiated based on the specific form of the umbrella and its extensions of the tentacle bulbs, characteristic of the family Pandeidae as described by Russell (1953), Kramp (1959, 1961) and Bouillon et al. (2006). Long exumbrellar spurs extending above the tentacle bulbs are typical of the genus Eutiara but the eight tree-like ramified ribs, extensions of the exumbrellar spurs, which nearly cover the exumbrella, seem to be specific to this new species, Eutiara decorata.

The crown-of-thorns seastar (COTS; Acanthaster spp.) inhabits coral reefs across the Pacific Ocean. Based on studies in the Western Pacific, when densities exceed ∼15 specimens per ha, coral reef degradation due to COTS predation may occur. There is little information about the role of COTS on coral reefs in the tropical eastern Pacific, although previous studies suggested it was not a concern to coral reef conservation in México. In this study, we estimated the abundance and impact of COTS on coral reefs at Espíritu Santo Archipelago National Park (Gulf of California) over a period of 12 years (2005–2016). The mean density (pooled among sites and over time) of COTS was 70 ± 5.1 ind. ha^–1 (mean ± SE), with a maximum value of 143.6 ± 30.3 ind. ha^–1, recorded in 2006. Densities changed significantly over time and spatially. The highest values were observed at sites located on the west side of the islands. Density was not correlated with seawater temperature or live coral cover. The absence of evidence of major live coral cover declines associated with predation by COTS, even though high densities were observed through the years in the region, lead us to conclude that this seastar does not appear to threaten coral reefs at Espíritu Santo. However, continued monitoring of COTS is required to help understand density fluctuations and to identify threshold densities needed to cause major coral damage in the region.

The size–structure of coral populations can serve as an indicator of demographic structure and response to disturbance. This study examines variation in the size–structure of Acropora and Pocillopora colonies, two regionally dominant coral genera with contrasting life-history traits. The abundance and colony sizes of these genera were studied across reef flats, crests, and slopes, within marine protected areas (MPAs) in New Ireland Province, Papua New Guinea (PNG), an understudied region of the Coral Triangle. While a preponderance of small sized colonies have been previously detected in relatively undisturbed reefs, this study instead found negatively skewed size–structures for Pocillopora and Acropora distributions, reflecting the general persistence of larger and likely older colonies. Pocillopora size-distributions were uniformly more negatively skewed and more peaked than Acropora, whereas, Acropora colonies were significantly larger across all reef positions and nearly all sites, potentially reflecting their high growth rates and ‘competitive’ life-history traits. The size–structure (skewness and kurtosis) of both Pocillopora and Acropora did not significantly vary across reef positions or study sites, whereas mean-colony size decreased significantly with deeper reef positions, suggesting that colonies of all size-classes respond in unison to micro-site reef heterogeneity at the regional scale. Together, this study provides valuable insight into the size–structure of dominant coral taxa with contrasting life-history traits, which will serve as baseline data for future surveys of coral community responses to climate change in PNG.

During specific inventories led by the Muséum national d'Histoire naturelle (MNHN, Paris), numerous specimens of Atyidae, particulary of Atya-like shrimps were collected in Melanesia (Vanuatu, Solomon Islands) and in Polynesia (Futuna, Samoa). These specimens were morphologically and genetically examined. Our study revealed that some specimens belonged to a new species in the genus AustralatyaChace, 1983. The aim of this paper is to describe this new species, Australatya keithi sp. nov., and discuss the distribution of its genus in the studied area.

An invasive thrips species (Klambothrips myopori, Thysanoptera), originally from Australia, attacks and inflicts severe damage to endemic Myoporum species in Hawai‘i. There is concern that the thrips will cause local extinctions of Myoporum in Hawai‘i. This study examined susceptibility of different Myoporum populations from various Hawaiian Islands to K. myopori infestation and dieback of aerial plant parts. Experimental exposures of plants from different populations were conducted in common garden studies. All M. sandwicense populations included in the study were highly susceptible to infestation and severe dieback of leaves and shoots occurred. Plants from a single M. stellatum population were less susceptible to attack and subsequent dieback of stems. Management options for populations under pressure from K. myopori are discussed.