G. Ebert results 30
· Newest (Page 1/2, per page 25)
Author: G. Ebert ×Clear All Filters
Search Results
We report the first live in situ observations of the iconic goblin shark ( Mitsukurina owstoni ) on a seamount near Jarvis Island in 2019 and on the slope of the Tonga Trench in 2024. Past observations are restricted to specimens hauled to the surface, resulting in limited knowledge of this species' ecology. These observations extend its known geographic and depth range considerably, and extend the depth range of lamniform sha...
Molecular taxonomy of the guitarfish genus Acroteriobatus (Rhinopristiformes: Rhinobatidae)NARA Subscribed
Guitarfish species (genus Acroteriobatus ) display restricted distributions in undermanaged regions of intense fishing pressure. The importance of accurate specimen identification is well established, especially in the context of conservation management. However, guitarfishes remain poorly understood, which is exacerbated by taxonomic uncertainty due to morphological similarity. We therefore aimed (1) to identify molecular ope...
Permafrost Thaw Accelerates Old Soil Carbon Release, Outpacing New Plant Inputs During a 13‐Year Tundra Warming ExperimentNARA Subscribed
Massive stores of ancient soil organic carbon (SOC) in permafrost can decompose with Arctic warming and accelerate global climate change. Declining SOC stocks are central to the permafrost carbon feedback, but direct measures of SOC loss are extremely rare due to methodological challenges related to subsidence in the Arctic. To fully capture changing SOC dynamics during thaw, we directly measured SOC stock and bulk soil radioc...
Non-invasive genetic sampling can be used in research, monitoring, and conservation of wild animals to, for example, provide insights into diets, identify individuals and estimate population sizes. Non-invasive genetic sampling may be especially useful to monitor elusive species because DNA can be derived from materials such as hairs and faeces without handling individuals. However, the reliability of the results derived from...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Among the largest fish species, the basking shark ( Cetorhinus maximus ) is found circumglobally in temperate and tropical waters. Though historical documents have recorded their presence in the California Current Ecosystem (CCE), basking sharks are now only rarely observed in this part of their range. We compiled recent and historical data from systematic surveys (1962–1997) and other sources (1973–2018) to (i) examine tempor...
Almost half of the global terrestrial soil carbon (C) is stored in the northern circumpolar permafrost region, where air temperatures are increasing two times faster than the global average. As climate warms, permafrost thaws and soil organic matter becomes vulnerable to greater microbial decomposition. Long‐term soil warming of ice‐rich permafrost can result in thermokarst formation that creates variability in environmental c...
Results presented here provide evidence of an exception to the generalization that all chondrichthyan populations are especially vulnerable to exploitation to the extent that they remain at low abundance for a protracted or indefinite duration even after exploitation rates are reduced. Delta log‐normal generalized linear models (GLM) and cluster analysis of fishery‐independent catch‐per‐unit‐effort (CPUE) data from 1977 to 200...
Stable‐isotope analysis of a deep‐sea benthic‐fish assemblage: evidence of an enriched benthic food webNARA Subscribed
In this study, fishes and invertebrates collected from the continental slope (1000 m) of the eastern North Pacific Ocean were analysed using stable‐isotope analysis (SIA). Resulting trophic positions ( T P ) were compared to known diets and habitats from the literature. Dual isotope plots indicated that most species groups (invertebrates and fishes) sorted as expected along the carbon and nitrogen axes, with less intraspecific...
Assessment of the dorsal fin spine for chimaeroid (Holocephali: Chimaeriformes) age estimationNARA Subscribed
Previous attempts to age chimaeroids have not rigorously tested assumptions of dorsal fin spine growth dynamics. Here, novel imaging and data‐analysis techniques revealed that the dorsal fin spine of the spotted ratfish Hydrolagus colliei is an unreliable structure for age estimation. Variation among individuals in the relationship between spine width and distance from the spine tip indicated that the technique of transverse s...