I present data on the Mariana Crow for an extensive but previously unavailable set of population and habitat surveys from 1992 to 1993. From these, I (1) compute a series of population estimates from that period during which Mariana Crow numbers were first entering a precipitous decline, (2) quantitatively assess the habitats occupied by individual birds and thereby provide a view of the range of habitats occupied during a time when the species was still widespread, and (3) provide the first direct wet-dry season comparisons of populations and habitat occupancy. Surveys yielded significantly different wet (943) and dry season (459) population estimates, which suggested wet season courtship activity preceding dry season nesting when birds became more secretive. Moreover, they indicated that the critical turning point in population decline was after 1995. Forest was the principal habitat type occupied during both wet and dry seasons, with savanna present less than half as often as forest, although birds occupied a range of additional habitats. The species was more versatile in habitat use than is often assumed, as rates of habitat occupancy and availability were similar. Versatility is an advantage for populations confined to small islands that periodically suffer catastrophic habitat damage due to typhoons.

Sida fallax Walp. (‘ilima) (Malveae, Malvoideae, Malvaceae) is native to the Pacific area and is broadly distributed throughout this region. Sida fallax is the most widespread and variable taxon of Malvaceae in the Hawaiian Islands and it occurs with diverse morphological forms and in different habitats from Hawai‘i Island to Midway Atoll. The low elevation and mountain ecotypes are two extreme ecological forms of S. fallax with many intermediate morphological types existing between these extreme ecotypes in the Hawaiian Islands. The range of morphological and ecological diversity in Sida fallax suggests that this species requires further biosystematics investigation. The purpose of this study was two-fold. First, explore the genetic diversity among S. fallax populations throughout its native range in the Pacific region to assess if it is a single species or potentially multiple cryptic species; second, investigate the biogeographic origin of S. fallax. To do this, Sida fallax was sampled throughout the Hawaiian Islands and in different parts of the Pacific region. Bayesian phylogenetic analyses based on nuclear (ITS and ETS) and chloroplast regions (psbA–trnH) were carried out. Results indicate that there is very little sequence-level variation in this species throughout its distribution and phylogenetic analysis clearly demonstrated that Sida fallax is a single species throughout the Pacific region and the different forms of Hawaiian S. fallax are not genetically distinct at the sequence level. Although the pattern of dispersal of S. fallax is not clear, an American origin is most likely.

This is the first report of plastics ingestion by the neotropical fish Dormitator latifrons. The stomach contents of 20 specimens (10 males and 10 females) collected in La Segua wetland (Ecuador) were assessed visually. Frequency of occurrence (FO) of plastics was 50% and the plastic load (PL) was between 5 and 55 particles per individual. Ninety-seven percent of plastic particles found were microplastics (<5.0 mm), and 3% were larger. No significant differences were found in PL between females and males (>0.05). No significant correlation was found between fish size and PL (>0.05). Fibers were the most frequently observed category, and transparent and blue colors were the most abundant. The results suggest high levels of plastic pollution in waters of La Segua wetland that may represent a threat to both the ecosystem and the people who rely on it.

In nesting areas with extreme climatic conditions, such as high temperatures, it is advisable to use mitigation strategies that counteract these negative effects on the hatching success of sea turtle nests. We evaluated the effect of incubation treatment on hatching success and incubation period for olive ridley turtles Lepidochelys olivacea during the 2019 nesting season in Guerrero, Mexico. Three incubation treatments (T1 = shade & freshwater irrigation; T2 = shade, seawater pre-irrigation, sand covered & freshwater irrigated; T3 = shade, seawater pre-irrigation, covered with a plastic lid & freshwater irrigated) were trialed at two different times during the nesting season. One of our goals was to compare the reproductive success of hatchery nests versus in situ nests, however, in situ nests hatching success was zero. We found that treatments had no effect on hatching success or incubation period, but there were differences in proportions of dead and crushed hatchlings. Clutches incubated in the second relocation period had longer incubation times. However, nest relocation periods had no effect on hatching success, dead hatchlings, or the proportion of crushed hatchlings. Our results also showed that the amount of seawater applied to the holes and the rate of irrigation were not lethal for the incubating eggs, but prolonged the incubation period. These results could help to increase our understanding of sea turtle reproductive success and may serve as a baseline to adapt the spatio-temporal conditions of the hatcheries in other areas with similar environmental conditions.

Sandyella tricornuta (Hendrickx, 1990) is a small (<13 mm total length), obligate and highly specific ectosymbiont of the black coral Antipathes galapagensis Deichmann, 1941 with a remarkable morphology and body coloration that resembles black coral polyps. Sandyella tricornuta population structure was investigated to infer the reproductive periods evidenced with ovigerous females from monthly collection at Espíritu Santo Island (April 2009–March 2010) and along a latitudinal gradient of six islands (24–30° N, July 2009) located along the west coast of the Gulf of California, Mexico. A total of 2,899 S. tricornuta individuals were collected from 70 colonies of A. galapagensis with a mean density of 210 inds./m³ per black coral colony. Sea floor temperature of S. tricornuta/A. galapagensis habitat seasonally ranged between 21 and 30°C. Females constituted >60% of the entire S. tricornuta population and >59% of the collected females were ovigerous females, suggesting active reproduction throughout the year and along the latitudinal gradient investigated. Sandyella tricornuta population density and sex ratio was similar throughout the year indicating a seasonally stable population size. Total abundance of S. tricornuta was density independent of black coral colony size and weight indicating that S. tricornuta depends on A. galapagensis, but the black coral colony can grow and develop without S. tricornuta characteristic of a commensalism ectosymbiotic association.

The Solomon Islands host a diverse terrestrial vertebrate fauna which has played a formative role in the development of speciation theory. Yet, despite over a century of biological exploration in the region, there are many islands for which we have incomplete knowledge of the vertebrate fauna. In 2019, we spent 20 days on Tetepare Island in the Western Province, Solomon Islands. Tetepare has a long history of conservation action by local communities and it is now the largest uninhabited tropical island in the world. We recorded 57 species of birds, 13 mammals, 5 amphibians, and 21 reptiles. Of these, we documented six species for the first time on Tetepare by western scientists: one frog, three non-avian reptiles, and two mammals. These findings point to a continued need for basic biological inventory work to inform research, local conservation efforts, and to increase published knowledge of the biodiversity in the Solomon Islands.