Kernel oils of jatropha (Jatropha curcas) and da’ok (Calophyllum inophyllum) obtained in Guam were characterized for physio-chemical properties as potential biodiesels including calorific content, iodine value, peroxide value, saponification value, acid value, and moisture content. Jatropha oil had lower acid value, peroxide value and moisture content than da’ok crude oil. Additional pre-treatment of da’ok crude oil was necessary to prevent potential problems when converting to biodiesel. Crude oils of two species were converted to biodiesel using a supercritical methanol method. The composition of fatty acid methyl esters (FAMEs) indicated that both crude oils and converted biodiesel of jatropha and da’ok contained palmitate (C16:0) with the range of 11.8-16.8% by weight, stearate (C18:0) with 6.5-8.6%, oleate (C18:1) with 40.5-52.6%, and linoleate (C18:2) with 22.0- 34.2%. Based on FAMEs, the cetane number was determined for jatropha and da’ok biodiesel as 52.7 and 54.1, respectively, indicating that both kernel oils were good source of feedstock to produce high quality biodiesel.

 

Fallen, senescent leaves of tree heliotrope (Heliotropium foertherianum), a ubiquitous shoreline tree from the Indian Ocean, tropical Asia, Australia, and the western and central Pacific, are a novel food item for green turtles (Chelonia mydas) in Hawaiʻi. Leaves were collected in two seasons and analyzed for proximate nutrients, including dry matter, ash, crude fat, crude protein, carbon:nitrogen (C:N) ratio, gross energy, as well as dietary fibers (ADF and NDF), lignin, and total phenol content. The senescent leaves showed a high C:N ratio, and measurable phenolic compounds, but were low in protein (x = 5.5%) and fat (x = 2.2%) based on dry weight. Gross energy averaged >4500 Kcal/kg ash-free dry weight; therefore, H. foertherianum could provide more calories than other marine food sources for Hawaiian green turtles. Green turtles elsewhere within the broad geographic range of tree heliotrope’s distribution may also consume senescent leaves that fall into coastal waters.

The distribution limits of North Pacific loggerhead turtles, Caretta caretta, within the Sea of Japan are unknown, but are suspected to be linked to a decrease in winter sea surface temperature. Immature loggerheads in the Sea of Japan are thought to follow the prevailing current via a southern route, or to leave from the north with extensions of the warm current, or are unable to leave when winter approaches. Here, we investigated the migrations of 30 immature captive-reared turtles of 26.5 to 75.2 cm SCL at 2–6 years of age released off the central Sea of Japan in summer of 2011 using satellite telemetry to ascertain 1) the seasonal movements of immature loggerheads and 2) their behavior in the subarctic zone. Nineteen turtles successfully left the Sea of Japan, mainly via the Soya Straittraveling into the North Pacific; however, eleven did not leave and may have died due to stranding during the winter. Their excursion paths were similar to migrations of wild turtles. The presence of exit routes suggests that immature loggerheads entering the Sea of Japan can disperse successfully and contribute to the North Pacific subpopulation. During the summer of 2011, the turtles that left the Sea of Japan experienced water temperatures that were relatively wide ranging and lower than turtles that stayed in Sea of Japan. The sea surface temperatures (SSTs) experienced by the turtles that left the Sea of Japan were significantly different from those of the time percent temperatures (TPTs) (range: 17–35 °C vs. 5–35 °C, mode: 23–25 °C vs. 10–15 °C). The relatively lower TPTs may be due to their active diving behaviors. In contrast, the SSTs and TPTs (range: 10–35 °C, mode: 21–23 °C) experienced by the turtles that stayed in the Sea of Japan were almost identical. Success in leaving the Sea of Japan could be related to a higher frequency of dives, although further research is required to confirm this.

We recorded observations of a Narcissus Flycatcher (Ficedula narcissina) and a Chestnut-winged Cuckoo (Clamator coromandus) on Guam, the southernmost and largest of the Mariana Islands. The flycatcher was seen once, on 23 October 2017, while the cuckoo was observed on seven occasions from 5 to 28 December 2017. Both species were found at night, during Brown Treesnake (Boiga irregularis) searches in the northern part of the island. These are the first records of the species for Guam and the Mariana Islands.

Oxygen uptake rates in air and water were measured at 26.0 and 32.0°C for common mudskipper Periophthalmus kalolo collected from sun-exposed mudflats, and barred mudskipper Periophthalmus argentilineatus taken from shaded mangal zones on Hoga Island, Sulawesi, Indonesia. Mass-adjusted oxygen consumption rates between mudskippers were statistically similar, with both species exhibiting higher uptake in air than water. Periophthalmus kalolo at 26.0 and 32.0°C had respective uptake values of 0.295 and 0.358 mg g^(0.75)−1 hr⁻¹ in air, and 0.198 and 0.241 mg g^(0.75)−1 hr⁻¹ in water. Periophthalmus argentilineatus at 26.0 and 32.0°C had oxygen uptake values of 0.262 and 0.343 mg g^(0.75)−1 hr⁻¹ in air, and 0.199 and 0.246 mg g^(0.75)−1 hr⁻¹ in water. While metabolic rates increased significantly in both species following an acute increase in media temperature, the change was not large, indicating a reduced metabolic response to increasing environmental temperatures. Respective temperature quotients calculated from aerial and aquatic metabolic rate data were 1.38 and 1.39 for P. kalolo, and 1.56 and 1.42 for P. argentilineatus. The data reveal that P. kalolo and P. argentilineatus exhibit similar metabolic responses when exposed to changes in media and temperature, even though each experiences markedly different diel habitat temperature profiles and insolation patterns.

 

The brown treesnake’s (Boiga irregularis – BTS) invasion of Guam is a primary example of the devastation an invasive predator can have on island ecosystems. Its introduction following WWII caused the extirpation of most of the island’s avifauna, although some native species have managed to persist in the presence of BTS, including a small population of Micronesian starlings (Aplonis opaca) on a military installation (Andersen Air Force Base – AAFB) in northeastern Guam. However, it remains unclear to what extent BTS predation continues to impact the population, particularly during the vulnerable post-fledging period. We report the first direct observations of BTS predation on Micronesian starling fledglings (n = 15). All 15 snakes that consumed starlings were in good to exceptional body condition and most were found in urban habitat within 100m of the nest box of the depredated fledgling. Following the predation events, snakes tended to seek refugia and remain inactive for 4 ± 1.67 (mean ± SD) days. Our findings provide evidence of ongoing BTS predation of a native bird species in areas undergoing operational snake removal and indicate that current control efforts are not sufficient to prevent BTS from encroaching into urban areas on AAFB to access high quality prey resources such as birds and mammals. Our data on snake movement and activity patterns following predation events will provide useful management information for future conservation and restoration efforts on Guam.

The persistent, non-native invasive alga Gracilaria salicornia has dominated the protected waters surrounding Moku o Loʻe, Kāneʻohe Bay since its introduction in 1978; however, a sudden decline in abundance (75%) occurred within a 30-day survey period. The consisent environmental conditions during the survey period, dominance of G. salicornia despite the presence of abundant herbivorous fish populations, and multiple observations of physical grazing by the green turtle, Chelonia mydas, on G. salicornia support our conclusion that C. mydas was the primary driver of the rapid decline of a persistent invasive macroalgae within a Hawaiian marine reserve. These findings highlight the need for high herbivore functional diversity with species-specific differences in dietary preference and feeding strategy, which should more efficiently suppress the growth and spread of any given macroalga and indirectly benefit coral reefs.

Sea turtle conservation is often hindered by the lack of reliable information on population status and threats due to sampling difficulties of these highly migratory reptiles that live in remote and data-poor locations. This paper summarizes more than a decade of stranding recoveries (live and dead turtles) on the islands of Saipan and Tinian, Commonwealth of the Northern Mariana Islands (CNMI), to obtain baseline information on the primary threats to sea turtles in the CNMI. Gross external examination and necropsy of dead turtles was used to infer primary cause of stranding of 89 sea turtles (92.1% green (Chelonia mydas), 5.6% hawksbill (Eretmochelys imbricata), 1.1% olive ridley (Lepidochelys olivacea), and 1% unknown). Of these stranding recoveries, 80.9% were juveniles, 15.7% were adults, and 3.4% were unknown. Trauma related to illegal human take was the primary cause of stranding and accounted for 79% of CNMI sea turtle injuries and mortalities. The remaining 21% of strandings were attributed to (in rank order): marine debris entanglement, shark bite, boat strike, emaciation, and infectious disease. This study provides the first comprehensive characterization of cause-specific sea turtle injury and mortality in CNMI, described within the unique socio-cultural and historical dynamics of the region. Culturally-relevant suggestions for management are provided that may help address the primary threat to CNMI sea turtles.