David Hatch results 25
· Newest (Page 1/1, per page 25)
Author: David Hatch ×Clear All Filters
Search Results
Role of Liming and Nitrogen Input in Determining Low Nitrogen Leaching Losses in Volcanic SoilsNARA Subscribed
Purpose Livestock production based on grazing is the most important productive activity in southern Chile. Most grasslands are located on volcanic soils with unexplained low nitrogen (N) leaching losses. Methods A cutting field experiment was carried out between February 2008 and March 2010 on an Andisol of the Osorno soil series, testing liming (0 or 2 t CaCO 3 ha − 1 yr − 1 ) and N rate applied as inorganic fertiliser applie...
Spatial distribution of selenium-mercury in Arctic seabirdsNARA Subscribed
PMEL Passive Acoustics Research: Quantifying the Ocean Soundscape from Whales to Wave EnergyOA Marine
Passive acoustic monitoring of the global ocean has increased dramatically over the last decade, providing insights into seasonal sea ice and wind/wave variability, biodiversity, geophysical hazards, and anthropogenic noise impacts. All of these phenomena are sentinels of marine ecosystem health and ocean climate change. Recognizing the utility of underwater sound, the Pacific Marine Environmental Laboratory (PMEL) formed a pa...
Wind patterns shape migratory pathways and detours of many procellariiform bird species that seasonally migrate between hemispheres. These seabirds are long-lived, and the period of immaturity is presumed to be a time of development and learning the environment, specifically how to use wind to their advantage. We assess how wind encountered by individual Great Shearwaters ( Ardenna gravis ) varies along the migration journey a...
Large Vessel Activity and Low-Frequency Underwater Sound Benchmarks in United States WatersOA Marine
Chronic low-frequency noise from commercial shipping is a worldwide threat to marine animals that rely on sound for essential life functions. Although the U.S. National Oceanic and Atmospheric Administration recognizes the potential negative impacts of shipping noise in marine environments, there are currently no standard metrics to monitor and quantify shipping noise in U.S. marine waters. However, one-third octave band acous...
Heatwave‐induced synchrony within forage fish portfolio disrupts energy flow to top pelagic predatorsNARA Subscribed
During the Pacific marine heatwave of 2014–2016, abundance and quality of several key forage fish species in the Gulf of Alaska were simultaneously reduced throughout the system. Capelin ( Mallotus catervarius ), sand lance ( Ammodytes personatus ), and herring ( Clupea pallasii ) populations were at historically low levels, and within this community abrupt declines in portfolio effects identify trophic instability at the onse...
Sex and hatching order modulate the association between MHC‐II diversity and fitness in early‐life stages of a wild seabirdNARA Subscribed
Genes of the major histocompatibility complex (MHC) play a pivotal role in parasite resistance, and their allelic diversity has been associated with fitness variations in several taxa. However, studies report inconsistencies in the direction of this association, with either positive, quadratic or no association being described. These discrepancies may arise because the fitness costs and benefits of MHC diversity differ among i...
Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate‐driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke ( Balaenoptera acutorostrata...
Biogeography of pelagic food webs in the North PacificNARA Subscribed
The tufted puffin ( Fratercula cirrhata ) is a generalist seabird that breeds throughout the North Pacific and eats more than 75 different prey species. Using puffins as samplers, we characterized the geographic variability in pelagic food webs across the subarctic North Pacific from the composition of ~10,000 tufted puffin meals (~56,000 prey items) collected at 35 colonies in the Gulf of Alaska (GoA) and Aleutian Archipelago...
Complex interactions among temporal variables affect the plasticity of clutch size in a multi‐brooded birdNARA Subscribed
Phenotypic plasticity is a widespread phenomenon and may have important influences on evolutionary processes. Multidimensional plasticity, in which multiple environmental variables affect a phenotype, is especially interesting if there are interactions among these variables. We used a long‐term data set from House Sparrows ( Passer domesticus ), a multi‐brooded passerine bird, to test several predictions from life‐history theo...
Previous1Next