The study of nocturnally active bats is difficult even for those species that seasonally congregate. This challenge is particularly acute for ‘ōpe‘ape‘a (Hawaiian hoary bat; Lasiurus semotus) because of its solitary foliage-roosting behavior. Yet surveys are essential for conservation and management of this endangered species and only land mammal endemic to the Hawaiian Islands. We surveyed for ‘ōpe‘ape‘a at 23 sites and a range of elevations (33–2,341 m) on Hawai‘i Island from May 2018 to August 2021. We captured 138 unique bats (37 female, 101 male) over 224 mist-netting events. We averaged 16 net-hours per bat capture, with peak captures 30–90 min after sunset. We marked all captured individuals in this study with identifying forearm bands and recaptures represented 7% of total captures (10 of 148). We developed generalized linear mixed models to examine the relationship of nightly bat captures by sex to elevation and time-of-year while accounting for variable sampling effort and repeated sampling in this study. Both males and females were captured at low and high elevations with peak capture rates occurring at approximately 930 m. The capture rate for females was highest during the reproductive season (May to September), whereas it was highest for males during the non-reproductive season (October to April). This study informs future fieldwork with a description of ‘ōpe‘ape‘a capture on Hawai‘i Island by sex, elevation, time-of-year and time-of-night, radio transmitter retention, and recapture frequency.

Among the impacts of human disturbance on forests, changes in soil nutrients and carbon stocks are of prime concern. Soil physicochemical properties were investigated at three depths in tropical rainforest converted to degraded secondary forest and mahogany plantation in Naitasiri province, Fiji. The mean values of pH, EC and CEC were 5.13, 0.06 mS/cm and 23.70 me/ 100 g respectively. Soils were low in total carbon (3.10%), total nitrogen (0.23%), Olsen available phosphorous (0.87 mg/kg), exchangeable calcium (483.83 mg/kg), exchangeable potassium (163.57 mg/kg) and sodium (10.67 mg/kg), while exchangeable magnesium (193.50 mg/kg) was moderate in concentration. This study showed that forest disturbance affects soil physicochemical properties (pH, EC, Ca, Mg, Na, Mn, Cu, Zn), and soil physicochemical properties vary with soil depth (EC, total C%, total N%, Ca, K, Na, Fe, Mn, Cu, Zn). Though not all pairwise differences were detectable statistically, yet undisturbed primary rainforest and plantation had higher pH, EC, CEC, total C %, soil organic matter %, total N%, Ca, Mg, Mn, Cu, Zn and Fe than the disturbed secondary forest. All examined soil parameters except pH, decreased with increase in soil depth. Relatively poor nutrient status of the disturbed secondary forest was associated with higher human interference, invasive species and faulty land management practices. Long undisturbed plantations managed for conservation purposes can regain nutrient pools of native forests in time. Understanding implications of human modification on soil nutrients in tropical ecosystems is therefore imperative for conservation, climate change mitigation and informed decision making in the land management sector.

Hibiscus denisonii Burb. came to international attention in English horticulture in 1876, having been sourced from Australian gardens, and generally believed to have come from the South Pacific Islands. It was described as a distinctive creamy white-flowered hibiscus with thick-leathery, dark-green, ‘ivy-like’ leaves that were different from those of other hibiscus then in cultivation. Burbidge’s H. denisonii has a hybrid origin and appears to have almost vanished from cultivation, aside from a morphologically matching hibiscus of undocumented origin growing in the Jardín de Aclimatación de la Orotava, Tenerife, Canary Islands. The name Hibiscus denisonii has long been associated with a similar white to light pink flowered hibiscus species, under cultivation in European botanical gardens, and here described as Hibiscus mabberleyi L.A.J. Thomson. Hibiscus mabberleyi is distinguished from H. × denisonii by its thinner, more slender and hirsute leaves; a more open, upright growth habit and characteristic breeding true-to-type from selfed seed. The genetic affinities of H. mabberleyi are with Mascarene Islands species in sect. Lilibiscus including H. boryanus DC., H. fragilis DC., H. genevei Bojer and and H. liliiflorus Cav. Recommendations are made for further research and ex situ conservation of H. mabberleyi.

Autonomous Recording Units (ARU) are a passive acoustic monitoring technology that are useful for detecting the presence and distribution of cryptic and nocturnal animals in challenging, remote environments as they can be deployed for extended periods of time. However, ARUs vary in their detection ability, thus making it critical to evaluate them in real world environments. In American Samoa, three Procellariiform seabird species nest on the remote island of Ta‘ū in difficult to access summit scrub habitat, for which we have little knowledge about their presence. Given the lack of knowledge about the distribution of these three species, coupled with the need to test different ARUs, our goal was to investigate the differences in detection probability for Song Meter sensors (Song Meter SM2 and SM4) under different habitat and environmental conditions on the island of Ta‘ū Detection ranges for seabird calls varied from <10 m in high wind conditions, up to 90 m in low wind conditions. Under ideal conditions detection range varied from 40 to 100 m for Song Meter SM4 sensors and 40 to 70 m for SM2 sensors. Knowing the detection capabilities of ARUs will allow better design of sensor spacing, and a combination of acoustic recording with in situ weather data will allow for calculations of detectable areas and facilitation of determining animal densities.

Because of its extreme isolation and lack of historical connection to a mainland, the Hawaiian Archipelago is thought to have no native nonvolant terrestrial reptiles. Several squamate species have been introduced to the archipelago, likely starting with early Polynesian contact, and increasing as human traffic in the Pacific has amplified. Of the earlier introductions, one species of skink, Cryptoblepharus poecilopleurus, belongs to a genus known for its ability to naturally disperse long distances, even across oceans. The earliest herpetofaunal surveys from Hawai‘i describe the skink as widespread and abundant across the archipelago. A recent phylogenetic analysis reveals substantial haplotype divergence between Hawaiian individuals and other known populations in the Pacific, raising the possibility that this species was an early and natural arrival to the archipelago before human contact. Recent surveys suggest that the species has undergone a dramatic reduction in range across the archipelago, possibly due to the invasion of highly competitive species. Given this information, we aim to further assess the origin of C. poecilopleurus in Hawai‘i, determine its current range, and suggest specific needs for future work. Here, we review the earliest European voyages in the Pacific that are known to have sampled C. poecilopleurus, review literature and museum specimens to develop an understanding of this species’ history in the islands, survey the island of O‘ahu to characterize its current range, and provide preliminary genetic analyses to show the relationship of the Hawai’i populations to the rest of the Pacific.

Seed dispersal and burial are important processes in the expansion and restoration of Zostera marina (eelgrass) meadows. The depth at which seeds are buried is a significant factor contributing to the success of seedling survival. If seeds are buried below 6 cm, it is unlikely that viable seedlings will develop, while shallow burials protect seeds from predation on the sediment surface. Burrowing behavior of infaunal organisms is one factor that contributes to seed burial with a potentially positive or negative influence on seedling survival. In this study, we designed a laboratory experiment to determine the relationship between lugworm (Abarenicola pacifica) density and eelgrass seed burial. Three treatments (no worms, low-density, and high-density of worms) with three replicates each were used to quantify seed burial. Each replicate was seeded with a blend of seed mimics and real seeds. After 25 days, three cores were extracted from each replicate and the depths of the seeds recorded. In the high-density worm treatments, most of the seeds and mimics were buried below the 6 cm critical depth, while in the low-density treatments most seeds were found shallower than 3 cm. These results agree with previous work on the burying capacity of infaunal organisms, and strongly suggest that the presence and activity of infauna can determine the success of Z. marina meadow expansion and restoration.

Rose-ringed parakeets (Psittacula krameri; parakeets) are among the most invasive bird species worldwide. In their introduced range, populations of this species have caused negative effects on native species, natural environments, economies, and human safety. Lethal population management has been complicated by the intelligence of the birds, as they quickly alter behavior to avoid risks. Further, lethal control programs have been halted due to public opposition, as parakeets are considered to be charismatic by animal welfare advocates. The contraceptive DiazaCon has been demonstrated to effectively reduce fertility in captive parakeets. In field applications, any chemical control agents (e.g., toxicants or contraceptives) must be delivered in a manner that prohibits access by non-target species. Parakeets are known to feed from bird feeders throughout their native and introduced range, suggesting contraceptive-treated bait may be a useful management strategy. However, our 24-week trials with free-ranging parakeets using platform, hopper, and tube feeders on the island of Kaua‘i did not result in any parakeet visitation and thus precluded further testing of using feeders to selectively deliver fertility control products. Nonetheless, multiple citizen science reports and other documentation indicate parakeets using feeders on the island of O‘ahu over a period of >10 years, and recently on the island of Maui. Our findings suggest the chemical control of nonnative parakeet populations is a promising technique, but implementation success will likely vary by target population acceptance, location, local faunal diversity, and availability of alternative forage.

The Brown Booby (Sula leucogaster) is a pantropical seabird that exhibits geographic variation. Brewster's Booby (S. l. brewsteri) is the most distinctive form morphologically and genetically. Until recently, Brewster's Booby was restricted to the eastern Pacific Ocean, but it is expanding westward, resulting in increasing sympatry with the Indo-Pacific form, S. l. plotus, and greater potential for interbreeding. We compiled observations of Brewster's Booby outside its usual range and we collected data on pairing patterns in the zone of overlap. At least 65 male and 53 female Brewster's Boobies have been observed on 20 islands in the central and western Pacific, with breeding documented on nine islands, mostly since 2000. Pairing by S. l. brewsteri and S. l. plotus was primarily assortative, with only a few instances of hybridization, all but one of which occurred in locations where no female S. l. brewsteri were present. The morphological differences between S. l. plotus and S. l. brewsteri appear to act as behavioral reproductive isolating mechanisms that restrict interbreeding. The morphological, genetic, and behavioral differences between S. l. brewsteri and other forms of the Brown Booby suggest it would be appropriate under all species concepts to consider Brewster's Booby as a distinct species.