ORCID Profile
0000-0003-4496-1367
Current Organisation
Atlantic Technological University
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Publisher: Springer Science and Business Media LLC
Date: 20-04-2014
Publisher: Fisheries Research and Development Corporation, Australia
Date: 2002
Publisher: Oxford University Press (OUP)
Date: 26-08-2016
Abstract: It is recommended that demersal elasmobranchs be managed using spatial proxies for Maximum Sustainable Yield. Here we combine escapement biomass—the percentage of the stock which must be retained each year to conserve it—with maps of predicted Catch Per Unit Effort (CPUE) of four ray species [cuckoo (Leucoraja naevus), thornback (Raja clavata), blonde (Raja brachyura), and spotted (Raja montagui)], created using Boosted Regression Tree modelling. We then use a Decision Support Tool to generate location and size options for Marine Protected Areas to protect these stocks, based on the priorities of the various stakeholders, notably the minimisation of fishing effort displacement. Variations of conservation/fishing priorities are simulated, as well as differential priorities for in idual species, with a focus on protecting nursery grounds and spawning areas. Prioritizing high CPUE cells results in a smaller closed area that displaces the most fishing effort, whereas prioritizing low fishing effort results in a larger closed area that displaces the least fishing effort. The final result is a complete software package that produces maps of predicted species CPUE from limited survey data, and allows disparate stakeholders and policymakers to discuss management options within a mapping interface.
Publisher: Elsevier BV
Date: 05-2014
Publisher: National Shellfisheries Association
Date: 08-2010
DOI: 10.2983/035.029.0213
Publisher: Fisheries Research and Development Corporation; State of Queensland, Dept. Employment, Economic Development and Innovation
Date: 2010
Publisher: Canadian Science Publishing
Date: 10-2004
DOI: 10.1139/F04-138
Abstract: This paper presents optimum s ling levels in discard s ling programs considering cost and precision objectives simultaneously and explores their dependence on both variables. The analysis is based on the Irish discard program: an onboard-observer voluntary s ling scheme aimed at estimating discard rates in trawl fisheries. Multistage analysis was performed to establish the precision levels achieved in the past, and a cost function was determined to estimate the financial cost of the program. Gear, fishing ground, targeted species, and International Council for the Exploration of the Sea (ICES) isions were the main factors affecting discarding, together with random effects of the three nested groups considered: haul, trip, and vessel. Reductions in the present budget will imply only marginal decreases in precision, although changes in cost variables can have an impact on s ling levels. On the other hand, increasing the target precision by one-half will imply a considerable increase in s ling and associated cost, which will be difficult if not impossible to achieve. Finally, the analysis by fleet components suggests a marked increase in s ling levels, which emphasizes the importance of clearly stated discard s ling objectives.
Publisher: Canadian Science Publishing
Date: 08-1996
DOI: 10.1139/F96-103
Publisher: Oxford University Press (OUP)
Date: 15-06-2015
Publisher: Elsevier BV
Date: 10-2005
Publisher: CSIRO Technical Working Group, CSIRO Port Phillip Bay Environmental Study
Date: 1996
Publisher: CSIRO Publishing
Date: 1999
DOI: 10.1071/MF97088
Abstract: Changes to the structure of fish communities in Port Phillip Bay between 1970 and 1991 were analysed by trawling at 14 stations s led regularly during 1970-75 and in 1990/91. Differences between stations were compared by using Bray-Curtis dissimilarity indices, multidimensional scaling and analysis of variance for the most abundant species. Differences between two s ling periods in the 1970s appear to be the result of the use of different vessels for trawling. A third vessel was used during 1990/91, but differences in catches between 1972-75 and 1990/91 appear to represent real temporal changes rather than differences between trawl efficiencies. Between 1972-75 and 1990/91, increased fishing pressure is the most likely explanation for declines in several important commercial and recreational species. A consequent decrease in competition may have caused an increase in the abundance of stingarees. A decline in seagrass abundance in the western bay probably reduced the abundance of several seagrass-dependent species. The Japanese goby was introduced into the bay after the mid 1970s, and populations of little rock whiting in the western bay and globefish in deep regions of Port Phillip Bay appear to have increased because of the recent establishment of additional exotic invertebrates.
Publisher: MDPI AG
Date: 04-08-2017
Publisher: CSIRO Technical Working Group, CSIRO Port Phillip Bay Environmental Study
Date: 1995
Publisher: Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania
Date: 2000
Publisher: Oxford University Press (OUP)
Date: 10-06-2014
Abstract: Fuel costs are an important element in models used to analyse and predict fisher behaviour for application within the wider mixed fisheries and ecosystem approaches to management. This investigation explored the predictive capability of linear and generalized additive models (GAMs) in providing daily fuel consumption estimates for fishing vessels given knowledge of their length, engine power, fleet segment (annual dominant gear type), and fuel prices. Models were fitted to half of the Irish fishing vessel economic data collected between 2003 and 2011. The predictive capabilities of the seven best models were validated against the remaining, previously un-modelled, data. The type of gear used by a fleet segment had an important influence on fuel consumption as did the price of fuel. The passive pot gear and Scottish seine gear segments indicated consistently lower consumptions, whereas dredge and pelagic gears showed consistently higher fuel consumptions. Furthermore, increasing fuel price negatively affected fuel consumption, especially for more powerful, larger vessels. Of the formulated models, the best fit to training data were a GAM with a gear main effect and two smooth functions standardized vessel length and engine power interacting with fuel price. For prediction, overall, this model showed the closest predictions with the least bias, followed by three linear models. However, all seven models compared for predictive capability performed well for the most s led segments (demersal and pelagic trawlers).
Publisher: Springer Science and Business Media LLC
Date: 30-01-2018
DOI: 10.1007/S12012-018-9446-2
Abstract: Ellagic acid (EA) is a phenolic constituent in certain fruits and nuts with wide range of biological activities, including potent antioxidant, antidiabetic, anti-inflammatory, anticancer and antimutagen properties. The aim of this study was to evaluate the effect of EA on sodium arsenic (SA)-induced cardio- and hematotoxicity in rats. Animals were ided into five groups. The first group was used as control. Group 2 was orally treated with sodium arsenite (SA, 10 mg/kg) for 21 days. Group 3 was orally treated with EA (30 mg/kg) for 14 days. Groups 4 and 5 were orally treated with SA for 7 days prior to EA (10 and 30 mg/kg, respectively) treatment and continued up to 21 days simultaneous with SA administration. Various biochemical, histological and molecular biomarkers were assessed in blood and heart. The results indicate that SA-intoxicated rats display significantly higher levels of plasma cardiac markers (AST, CK-MB, LDH and cTnI) than normal control animals. Moreover, an increase in MDA and NO with depletion of GSH and activities of CAT, SOD and GPx occurred in the heart of rats treated with SA. Furthermore, SA-treated rats showed significantly lower WBC, RBC, HGB, HCT and PLT and significantly higher MCV and MCH. Administration of EA (30 mg/kg) resulted in a significant reversal of hematological and cardiac markers in arsenic-intoxicated rats. These biochemical disturbances were supported by histopathological observations of the heart. In conclusion, the results of this study suggest that EA treatment exerts a significant protective effect on SA-induced cardio- and hematotoxicity.
Publisher: Canadian Science Publishing
Date: 11-1997
DOI: 10.1139/F97-157
Publisher: Elsevier BV
Date: 09-2015
Publisher: Springer Science and Business Media LLC
Date: 28-08-2012
Publisher: Oxford University Press (OUP)
Date: 23-12-2015
Abstract: Microplastics in the marine environment are well documented, and interactions with marine biota have been described worldwide. However, interactions with vertically migrating fish are poorly understood. The diel vertical migration of mesopelagic fish represents one, if not the largest, vertical migration of biomass on the planet, and is thus an important link between the euphotic zone, transporting carbon and other nutrients to global deep sea communities. Knowledge of how mesopelagic fish interact and distribute plastic as a marine contaminant is required as these populations have been identified as a potential global industrial fishery for fishmeal production. Ingestion of microplastic by mesopelagic fish in the Northeast Atlantic was studied. Approximately 11% of the 761 fish examined had microplastics present in their digestive tracts. No clear difference in ingestion frequency was identified between species, location, migration behaviour, or time of capture. While ingesting microplastic may not negatively impact in idual mesopelagic fish, the movement of mesopelagic fish from the euphotic zone to deeper waters could mediate transfer of microplastics to otherwise unexposed species and regions of the world's oceans.
Publisher: Wiley
Date: 1995
Publisher: Public Library of Science (PLoS)
Date: 07-12-2017
Publisher: Elsevier BV
Date: 05-2019
Publisher: Oxford University Press (OUP)
Date: 22-01-2017
Abstract: Expeditious uptake of quad-rig trawling in the economically important Irish fishery for Nephrops norvegicus outpaced technical understanding of this newly introduced gear. The main driver for its introduction is increased catch rates of Nephrops. Higher Nephrops discard rates associated with quad-rig trawling are likely to be problematic under the landing obligation unless size selectivity can be improved. Catch comparison methods are suitable for assessing the performance of fishing gear modifications to reduce discards. Utilizing a quad-rig potentially increases the number of gears that can be included in a catch comparison study to four but current modeling methods are limited to two gears. Our study provides a new general multinomial mixed effects modeling framework that can be applied to two or more gears, elucidates how case-specific and choice-specific covariates may influence catch at length, and facilitates discussion on appropriate gear based management measures. Application of the method to catches from four different cod-end mesh sizes revealed significant effects of carapace length, catch weight and net position, on the numbers of Nephrops retained in each cod-end. Results suggest that management measures which specifically address different catch profiles associated with different numbers of trawling rigs are required to optimize Nephrops size selectivity.
Publisher: American Chemical Society (ACS)
Date: 23-12-2016
Abstract: Waste water treatment plants (WWTPs) are receptors for the cumulative loading of microplastics (MPs) derived from industry, landfill, domestic wastewater and stormwater. The partitioning of MPs through the settlement processes of wastewater treatment results in the majority becoming entrained in the sewage sludge. This study characterized MPs in sludge s les from seven WWTPs in Ireland which use anaerobic digestion (AD), thermal drying (TD), or lime stabilization (LS) treatment processes. Abundances ranged from 4196 to 15 385 particles kg
Publisher: Hindawi Limited
Date: 23-12-2015
DOI: 10.1111/ARE.12959
Publisher: Elsevier BV
Date: 2012
Publisher: Oxford University Press (OUP)
Date: 2006
DOI: 10.1016/J.ICESJMS.2006.03.017
Abstract: Annual discard ogives were estimated using generalized additive models (GAMs) for four demersal fish species: whiting, haddock, megrim, and plaice. The analysis was based on data collected on board commercial vessels and at Irish fishing ports from 1995 to 2003. For all species the most important factors influencing annual discard ogives were fleet (combination of gear, fishing ground, and targeted species), mean length of the catch and year, and, for megrim, also minimum landing size. The length at which fish are discarded has increased since 2000 for haddock, whiting, and plaice. In contrast, discarded length has decreased for megrim, accompanying a reduction in minimum landing size in 2000.
Publisher: Springer Science and Business Media LLC
Date: 08-10-2015
DOI: 10.1038/SREP14947
Abstract: Plastic, as a form of marine litter, is found in varying quantities and sizes around the globe from surface waters to deep-sea sediments. Identifying patterns of microplastic distribution will benefit an understanding of the scale of their potential effect on the environment and organisms. As sea ice extent is reducing in the Arctic, heightened shipping and fishing activity may increase marine pollution in the area. Microplastics may enter the region following ocean transport and local input, although baseline contamination measurements are still required. Here we present the first study of microplastics in Arctic waters, south and southwest of Svalbard, Norway. Microplastics were found in surface (top 16 cm) and sub-surface (6 m depth) s les using two independent techniques. Origins and pathways bringing microplastic to the Arctic remain unclear. Particle composition (95% fibres) suggests they may either result from the breakdown of larger items (transported over large distances by prevailing currents, or derived from local vessel activity), or input in sewage and wastewater from coastal areas. Concurrent observations of high zooplankton abundance suggest a high probability for marine biota to encounter microplastics and a potential for trophic interactions. Further research is required to understand the effects of microplastic-biota interaction within this productive environment.
Publisher: Elsevier BV
Date: 09-2005
Publisher: Elsevier BV
Date: 09-2014
Publisher: Unpublished
Date: 2008
Publisher: Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania
Date: 1999
Publisher: Elsevier BV
Date: 05-2015
Publisher: Elsevier BV
Date: 04-2015
DOI: 10.1016/J.ENVPOL.2015.01.023
Abstract: When mammals strand, they present a unique opportunity to obtain insights into their ecology. In May 2013, three True's beaked whales (two adult females and a female calf) stranded on the north and west coasts of Ireland and the contents of their stomachs and intestines were analysed for anthropogenic debris. A method for identifying microplastics ingested by larger marine organisms was developed. Microplastics were identified throughout the digestive tract of the single whale that was examined for the presence of microplastics. The two adult females had macroplastic items in their stomachs. Food remains recovered from the adult whales consisted of mesopelagic fish (Benthosema glaciale, Nansenia spp., Chauliodius sloani) and cephalopods, although trophic transfer has been discussed, it was not possible to ascertain whether prey were the source of microplastics. This is the first study to directly identify microplastics <5 mm in a cetacean species.
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/MF9920923
Abstract: Shark vertebral centra show no histological evidence of resorption at any time in the animals' life. Deorganification of centra always reveals a large, residual, stable, three-dimensional skeleton. In contrast, the mineralized parts of other organs (e.g. claspers and jaws) crumble into their in idual mineralized subunits, the tesserae, upon deorganification. In both cases, only appositional growth of cartilage on the pre-existing mineralized template is possible. The basic 'double-cone' shape of the vertebrae facilitates increases in body length simultaneously with an accompanying increase in girth. Once the initial shape of the mineralized portion of a vertebral centrum is fully established and hence can be described, then relatively simple mathematical models might be devised to predict future growth patterns. To advance this hypothesis, it has first been necessary to develop a method that can accurately record the sizes and shapes of complex three-dimensional anatomical structures. This paper describes a technique that is capable not only of recording and measuring the size and shape of shark vertebrae but also of predicting their subsequent growth. Furthermore, the technique enables reproduction of three-dimensional coloured and shaded stereoscopic images of vertebral structures, facilitating a better understanding of their intricate morphology. Three-dimensional coordinate data gathered from any shark vertebra can be manipulated mathematically to model future vertebral growth. Producing realistic images of vertebrae transformed in this way may allow the exploration of possibly unrealized taxonomic affinities.
Publisher: Elsevier BV
Date: 11-2014
DOI: 10.1016/J.MARPOLBUL.2014.08.023
Abstract: Levels of marine debris, including microplastics, are largely un-documented in the Northeast Atlantic Ocean. Broad scale monitoring efforts are required to understand the distribution, abundance and ecological implications of microplastic pollution. A method of continuous s ling was developed to be conducted in conjunction with a wide range of vessel operations to maximise vessel time. Transects covering a total of 12,700 km were s led through continuous monitoring of open ocean sub-surface water resulting in 470 s les. Items classified as potential plastics were identified in 94% of s les. A total of 2315 particles were identified, 89% were less than 5mm in length classifying them as microplastics. Average plastic abundance in the Northeast Atlantic was calculated as 2.46 particles m(-3). This is the first report to demonstrate the ubiquitous nature of microplastic pollution in the Northeast Atlantic Ocean and to present a potential method for standardised monitoring of microplastic pollution.
Location: Australia
No related grants have been discovered for Rick Officer.