DAVID WHITEHEAD results 54
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This study develops a novel approach to forecasting anomalies of meat yield from mussel aquaculture in Pelorus Sound, New Zealand, based on the relationships between non-local sea surface temperature (SST) and observations of mussel meat yield over 13 years. Overall, we found strong associations between lagged SSTs in the Tasman Sea region and mussel meat yield, with a noticeable seasonal cycle in these relationships. Results...
Agricultural production has economic, environmental, social and cultural consequences beyond farm boundaries, but information about these impacts is not readily available to decision makers. This study applied the land use suitability concept by carrying out an assessment of a region that has the potential for intensification of agricultural production, but where eutrophication of river and estuary receiving environments due t...
Labile carbon inputs support the recovery of bacterial communities, but not fungal communities, from a simulated bovine urine eventNARA Subscribed
Inputs of carbon to soil may be used to stimulate microbial growth and immobilize excess nitrogen from sources such as livestock urine. However, the growth responses of microbial taxa to carbon inputs under conditions of excess soil nitrogen remain poorly understood. Using DNA metabarcoding and a field-based soil lysimeter experiment, we characterised the temporal responses (up to 112 days) of bacterial and fungal communities...
Potential for redistribution of post‐moult habitat for Eudyptes penguins in the Southern Ocean under future climate conditionsNARA Subscribed
Anthropogenic climate change is resulting in spatial redistributions of many species. We assessed the potential effects of climate change on an abundant and widely distributed group of diving birds, Eudyptes penguins, which are the main avian consumers in the Southern Ocean in terms of biomass consumption. Despite their abundance, several of these species have undergone population declines over the past century, potentially du...
This position paper summarizes the current understanding of biological nitrification inhibition (BNI) to identify research needs for accelerating the development of BNI as a N 2 O mitigation strategy for grazed livestock systems. We propose that the initial research focus should be on the systematic screening of agronomically desirable plants for their BNI potency and N 2 O reduction potential. This requires the development of...
Soil microbial sensitivity to temperature remains unchanged despite community compositional shifts along geothermal gradientsNARA Subscribed
Climate warming may be exacerbated if rising temperatures stimulate losses of soil carbon to the atmosphere. The direction and magnitude of this carbon‐climate feedback are uncertain, largely due to lack of knowledge of the thermal adaptation of the physiology and composition of soil microbial communities. Here, we applied the macromolecular rate theory (MMRT) to describe the temperature response of the microbial decomposition...
Unexpected role of communities colonizing dead coral substrate in the calcification of coral reefsNARA Subscribed
Global and local anthropogenic stressors such as climate change, acidification, overfishing, and pollution are expected to shift the benthic community composition of coral reefs from dominance by calcifying organisms to dominance by non‐calcifying algae. These changes could reduce the ability of coral reef ecosystems to maintain positive net calcium carbonate accretion. However, relationships between community composition and...
We developed a method to predict the susceptibility of New Zealand estuaries to eutrophication. This method predicts macroalgae and phytoplankton responses to potential nutrient concentrations and flushing times, obtained nationally from simple dilution models, a GIS land-use model and physical estuary properties. Macroalgal response was based on an empirically derived relationship between potential nitrogen concentrations and...
Habitat suitability of Rhincodon typus in three localities of the Gulf of California: Environmental drivers of seasonal aggregationsNARA Subscribed
The whale shark is an endangered species that usually feeds in coastal areas of highly productive seas such as the Gulf of California, Mexico. This study aims to describe the effect of sea surface temperature, chlorophyll a , bathymetry and slope on the habitat suitability of whale sharks in three important aggregation sites of the Gulf of California. A total of 2396 records of occurrence of whale sharks were obtained from int...
Seasonal trends in whale shark Rhincodon typus sightings in an established tourism site in the Gulf of California, MexicoNARA Subscribed
The number of individual whale shark Rhincodon typus sightings registered October 2015–March 2018 in Bahia de La Paz, Mexico, ranged from 73 to 129 animals per season (total 1662), with the majority of them identified as males. Density plot maps showed high correlations in sightings between sample seasons and revealed potential hotspot areas. Our study provides an essential baseline of information for the management of whale s...
The present study analyses whale shark Rhincodon typus stranding in the Gulf of California, Mexico, reported by the public, scientists, authorities and artisanal fishermen. A total of 14 strandings were documented during the period 2001–2018. The total length of R. typus ranged from 350–1,102 cm, with a sex ratio of 3.5:1 (males: females). This study highlights potential stranding areas, the need for better stranding protocols...