ROBERT OLSON results 89
· Newest (Page 1/4, per page 25)
Author: ROBERT OLSON ×Clear All Filters
Search Results
Diversity and functional group composition drive biogeographic patterns in marine biogenic structural complexityNARA Subscribed
Biogenic structural complexity is a key driver of biodiversity and ecosystem functioning, yet its ecological and environmental determinants remain poorly understood across broad biogeographic scales. Here, we conducted standardized 90‐day field experiments at 16 coastal sites, spanning a 41‐degree latitudinal gradient, using naturally assembled marine fouling communities on settlement panels. We measured rugosity as our metric...
Chilean Blue Whales: Fidelity to Feeding Areas and Migratory Connectivity With the Eastern Tropical Pacific 1NARA Subscribed
In the Eastern South Pacific (ESP), blue whale ( Balaenoptera musculus subsp.) aggregations have been described for two feeding areas (in northern and southern Chile) and in the Eastern Tropical Pacific (ETP). However, despite the knowledge of these areas, little is known about the seasonal movements of blue whales between them. Comparisons of 1074 individual blue whales, photographed across these regions from 1992 to 2019, re...
Local and Landscape‐Level Environmental Conditions Drive Habitat Selection Across Terrestrial Mammal SpeciesNARA Subscribed
Aim Animal movements are a fundamental process affecting communities and ecosystems. Quantifying habitat selection across species and habitats is key for understanding how animals respond to environmental change. Currently, we lack comparative studies that examine how habitat selection varies across species traits and landscapes. We aim to quantify global patterns of habitat selection to help understand the fundamental drivers...
Several legal acts mandate that management agencies regularly assess biological populations. For species with distinct markings, these assessments can be conducted noninvasively via capture‐recapture and photographic identification (photo‐ID), which involves processing considerable quantities of photographic data. To ease this burden, agencies increasingly rely on automated identification (ID) algorithms. Identification algori...
SNAPSHOT USA 2019–2023: The First Five Years of Data From a Coordinated Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multicontributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of specie...
Predation on Live and Artificial Insect Prey Shows Different Global Latitudinal PatternsNARA Subscribed
Aim Long‐standing theory predicts that the intensity of biotic interactions increases from high to low latitudes. Studies addressing geographic variation in predation on insect prey have often relied on prey models, which lack many characteristics of live prey. Our goals were to explore global latitudinal patterns of predator attack rates on standardised live insect prey and to compare the patterns in predation on live insects...
DNA simulation benchmarks revealed with the accumulation of high-resolution structuresNARA Subscribed
DNA carries more than the list of biochemical instructions that drive the basic functions of living systems. The sequence of base pairs includes a multitude of structural and energetic signals that determine the degree to which the long, threadlike molecule moves and how it responds to proteins and other molecules involved in its processing and packaging. The arrangements of successive base pairs in high-resolution protein-DNA...
SNAPSHOT USA 2021: A third coordinated national camera trap survey of the U nited S tatesNARA Subscribed
SNAPSHOT USA is a multicontributor, long‐term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application ( https://www.snapshot-usa.org/ ). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Her...
Phylogeography of Solomon Islands blossom bats reflects oceanic divides and Pleistocene connectionsNARA Subscribed
Aim Periodic lowering of sea levels and formation of land bridges can reshape phylogeographic patterns of insular biotas. Using archipelago‐wide sampling, we aimed to test if phylogeography of an old‐endemic bat lineage reflected Pleistocene land bridges. Location Solomon Islands and Papua New Guinea. Taxon Melonycteris and Nesonycteris bats (Pteropodidae). Methods We sequenced genome‐wide RADseq data for 49 specimens from 15...
A hydrologic perspective of major U.S. droughtsNARA Subscribed
Drought is a recurring natural hazard that has substantial human and environmental impacts. Given continued global warming and associated climate change, there is concern that droughts could become more severe and longer lasting. To better monitor and understand drought development and persistence, it is helpful to understand the development and climatic drivers of past droughts. In this study we use monthly runoff percentiles...
Direct observations of the oceans acquired on oceanographic research ships operated across the international community support fundamental research into the many disciplines of ocean science and provide essential information for monitoring the health of the oceans. A comprehensive knowledge base is needed to support the responsible stewardship of the oceans with easy access to all data acquired globally. In the United States,...
Evaluating expert‐based habitat suitability information of terrestrial mammals with GPS‐ tracking dataNARA Subscribed
Aim Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert‐based information is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert‐based information with detailed empirical evidence. Here, we compared expert‐based habitat suitability info...
Landscape-Scale Forest Reorganization Following Insect Invasion and Harvest Under Future Climate Change ScenariosNARA Subscribed
Emerald ash borer (EAB; Agrilus planipennis Farimaire) has been found in 35 US states and five Canadian provinces. This invasive beetle is causing widespread mortality to ash trees ( Fraxinus spp.), which are an important timber product and ornamental tree, as well as a cultural resource for some Tribes. The damage will likely continue despite efforts to impede its spread. Further, widespread and rapid ash mortality as a resul...
Nitrogen and carbon stable isotope data sets are commonly used to assess complex population to ecosystem responses to natural or anthropogenic changes at regional to global spatial scales, and monthly to decadal timescales. Measured in the tissues of consumers, nitrogen isotopes (δ 15 N) are primarily used to estimate trophic position while carbon isotopes (δ 13 C) describe habitat associations and feeding pathways. Models of...
Hydrokinetic tidal energy converter (TEC) technology is yet to become cost competitive with other renewable energy sources. Understanding the interaction between energy production and the costs incurred harvesting that energy may unlock the economic potential of this technology. Although hydrodynamic simulation of TEC arrays has matured over time, including demonstration of how small and large arrays affect the resource, integ...
Seasons of SynNARA Subscribed
Synechococcus is a widespread and important marine primary producer. Time series provide critical information for identifying and understanding the factors that determine abundance patterns. Here, we present the results of analysis of a 16‐yr hourly time series of Synechococcus at the Martha's Vineyard Coastal Observatory, obtained with an automated, in situ flow cytometer. We focus on understanding seasonal abundance patterns...
Trends in tuna carbon isotopes suggest global changes in pelagic phytoplankton communitiesNARA Subscribed
Considerable uncertainty remains over how increasing atmospheric CO 2 and anthropogenic climate changes are affecting open‐ocean marine ecosystems from phytoplankton to top predators. Biological time series data are thus urgently needed for the world's oceans. Here, we use the carbon stable isotope composition of tuna to provide a first insight into the existence of global trends in complex ecosystem dynamics and changes in th...