Landslide hypothesis for the origin of Haleakala volcano's crater and great valleys, Hawaii

Active Haleakala volcano on the island of Maui is the second largest volcano in the Hawaiian Island chain. Prominently incised in Haleakala's slopes are four large (great) valleys. Haleakala Crater, a prominent summit depression, formed by coalescence of two of the great valleys. The great valleys and summit crater have long been attributed solely to fluvial erosion, but two significant enigmas exist in the theory. First, the great valleys of upper Keanae/Koolau Gap, Haleakala Crater, and Kaupo Gap are located in areas of relatively low annual rainfall. Second, the axes of some valley segments are oblique for long distances across the volcanic slopes. This study tested the prevailing erosional theory by reconstructing the volcano's topography just prior to valley incision. The reconstruction produces a belt along the volcano's east rift zone with a morphology that is inconsistent with volcanic aggradation alone, but it is readily explained if it is assumed the surface was displaced along scarps formed by a giant landslide on Haleakala's northeastern flank. Although the landslide head location is well defined, topographic evidence is lacking for the toe and lateral margins. Consequently, the slope failure is interpreted as a sackung-style landslide with a zone of deep-seated distributed shear and broad surface warping downslope of the failure head. Maximum downslope displacement was likely in the range of 400–800 m. Capture of runoff at the headscarps formed atypically large streams that carved Haleakala's great valleys and explains their existence in low-rainfall areas and their slope-oblique orientations. Sackung-style landslides may be more prevalent on Hawaiian volcanoes than previously recognized.

Sun, Wind and Waves: EV Fossil Fuel Use and Emissions on an Isolated, Oil-Dependent Hawaiian Island

Electric power grids in remote communities around the world tend to be highly oil-dependent, unlike large, interconnected grids. Consequently, self-contained power grids such as the Hawaiian Islands’ have become testbeds for aggressive renewable energy integration (PV, wind, and ocean energy) and transportation electrification. However, there remains a lack of critical analysis for remote communities to determine the benefits of transitioning from internal combustion engine (ICE) vehicles to plug-in electric vehicles (EVs). This case study examines the impacts of this transition to EVs and renewable power generation on fossil fuel use and CO2 emissions on the oil-dependent Island of Oahu, Hawaii. Average passenger EVs were found to consume seven times less fossil fuel (the equivalent of 66 gallons of gasoline (GGe), than their gasoline-powered counterparts (455 gallons) in 2020. Average EVs also cut emissions in half, (2 MTCO2 versus 4 MTCO2). Several renewable power and EV transition scenarios were modeled to assess impacts out to 2050. Fossil fuel use and emissions plummet with more clean power and increasing EV numbers. By 2045, in the most ambitious scenario, all gasoline- and diesel-powered vehicles (passenger and freight) will consume a total of 8.8 billion GGe, and EVs 0.090 billion GGe (1%). ICE CO2 emissions will total 80 MMT, and EVs 4.4 MMT (5.5%). By 2050, the anticipated transition to electric passenger and freight vehicles combined with renewable power will lead to 99% less fossil fuel consumed, and 93% less CO2 emitted.

Hawaiian Paratachys Casey (Coleoptera, Carabidae): small beetles of sodden summits, stony streams, and stygian voids

Five Hawaiian species of Paratachys Casey are revised, including four newly described: Paratachys terryli from Kauai; P. perkinsi from Moloka‘i; P. haleakalae from Maui; and P. aaa from Hawai‘i Island. A lectotype is designated for the fifth Hawaiian species currently combined with Paratachys, Tachys arcanicola Blackburn, 1878 of Oahu. Hawaiian Paratachys spp. known from more than one specimen exhibit some degree of ocular polymorphism, that variation being extreme in P. terryli where individuals range in ocular development from macrophthalmic with broadly convex eyes to microphthalmic with small, flat eyes. All Hawaiian Paratachys species comprise individuals with vestigial wings, with the exception of P. terryli, where a single macropterous, macrophthalmic female complements the other 18 brachypterous specimens. Based on a transformation series of characters from the male aedeagus, the biogeographic history of Hawaiian Paratachys is consistent with progressive colonization of the Hawaiian Island chain. Three of the species do not appear to represent species of conservation concern, with P. terryli and P. haleakalae known from terrestrial deep soil, litter, and streamside microhabitats in montane wet rain forest, and the troglobitic P. aaa occupying the dark zone of numerous, recently developed lava tube caves within the Mauna Loa and Kilauea volcanic massifs. The conservation status of the other two species is much more dire, with P. arcanicola of O‘ahu not seen in nature since the early 20th Century, and P. perkinsi known only from a single specimen fortuitously collected in 1894 near sea level on Moloka‘i.

Schistocerca nitens (gray bird grasshopper).

S. nitens (Thunberg) is a short-horned grasshopper classified in the Family Acrididae. It is native to southwestern North America, Central America and northern South America. It was first reported as invasive in the Hawaiian archipelago in 1964 and is now present on all the main Hawaiian islands. S. nitens is solitary and non-migratory, but under certain conditions can form swarms or outbreaks and cause damage to crops and native plant species. In 2002 and 2004 outbreaks on the Hawaiian island of Nihoa posed a threat to all the vegetation on the island, particularly endangered plant species.

New Acetophenones and Chromenes from the Leaves of Melicope barbigera A. Gray

The dichloromethane extract from leaves of Melicope barbigera (Rutaceae), endemic to the Hawaiian island of Kaua’i, yielded four new and three previously known acetophenones and 2H-chromenes, all found for the first time in M. barbigera. The structures of the new compounds obtained from the dichloromethane extract after purification by chromatographic methods were unambiguously elucidated by spectroscopic analyses including 1D/2D NMR spectroscopy and HRESIMS. The absolute configuration was determined by modified Mosher’s method. Compounds 2, 4 and the mixture of 6 and 7 exhibited moderate cytotoxic activities against the human ovarian cancer cell line A2780 with IC50 values of 30.0 and 75.7 µM for 2 and 4, respectively, in a nuclear shrinkage cytotoxicity assay.

Theoretical Background

Imagine being born and raised on the Hawaiian island Kaua’i, close to the shield volcano Wai’ale’ale. On this island, yearly rainfall reaches 15 meters and more. You were stuck in this small region on this remote island your entire life, without any information ever having reached you to indicate that this extreme amount of rainfall was extra ordinary.

Post-release survival of fallout Newell’s shearwater fledglings from a rescue and rehabilitation program on Kaua‘i, Hawai‘i

Light attraction impacts nocturnally active fledgling seabirds worldwide and is a particularly acute problem on Kaua‘i (the northern-most island in the main Hawaiian Island archipelago) for the Critically Endangered Newell’s shearwater Puffinus newelli. The Save Our Shearwaters (SOS) program was created in 1979 to address this issue and to date has recovered and released to sea more than 30500 fledglings. Although the value of the program for animal welfare is clear, as birds cannot simply be left to die, no evaluation exists to inform post-release survival. We used satellite transmitters to track 38 fledglings released by SOS and compared their survival rates (assessed by tag transmission duration) to those of 12 chicks that fledged naturally from the mountains of Kaua‘i. Wild fledglings transmitted longer than SOS birds, and SOS birds with longer rehabilitation periods transmitted for a shorter duration than birds released immediately or rehabilitated for only 1 d. Although transmitter durations from grounded fledglings were shorter (indicating impacts to survivorship), some SOS birds did survive and dispersed out to sea. All surviving birds (wild and SOS) traveled more than 2000 km to the southwest of Kaua‘i, where they concentrated mostly in the North Pacific Equatorial Countercurrent Province, revealing a large-scale annual post-breeding aggregation zone for fledgling Newell’s shearwaters. While there was reduced survival among birds undergoing rehabilitation, SOS remains an important contribution toward the conservation of Newell’s shearwater because a proportion of released birds do indeed survive. However, light attraction, the root cause of fallout, remains a serious unresolved issue on Kaua’i.