Keyword

EARTH SCIENCE > OCEANS > AQUATIC SCIENCES > FISHERIES

28 record(s)
 
Type of resources
Topics
Keywords
Contact for the resource
Provided by
From 1 - 10 / 28
  • Edited version of a video showing three elephant seals interacting with a toothfish longline. Taken from the abstract of the referenced paper: Humans have devised fishing technologies that compete with marine predators for fish resources world-wide. One such fishery for the Patagonian toothfish (Dissostichus eleginoides) has developed interactions with a range of predators, some of which are marine mammals capable of diving to extreme depths for extended periods. A deep-sea camera system deployed within a toothfish fishery operating in the Southern Ocean acquired the first-ever video footage of an extreme-diver, the southern elephant seal (Mirounga leonina), depredating catch from longlines set at depths in excess of 1000m. The interactions recorded were non-lethal, however independent fisheries observer reports confirm elephant seal-longline interactions can be lethal. The seals behaviour of depredating catch at depth during the line soak-period differs to other surface-breathing species and thus presents a unique challenge to mitigate their by-catch. Deployments of deep-sea cameras on exploratory fishing gear prior to licencing and permit approvals would gather valuable information regarding the nature of interactions between deep diving/dwelling marine species and longline fisheries operating at bathypelagic depths. Furthermore, the positive identification by sex and age class of species interacting with commercial fisheries would assist in formulating management plans and mitigation strategies founded on species-specific life-history strategies.

  • This dataset covers the area of the Australian Exclusive Economic Zone (EEZ) around Heard Island and McDonald Islands (HIMI). The Fisheries sector areas were originally created by Dick Williams, former Fisheries biologist at the Australian Antarctic Division for the HIMI fishery, to define areas of research fishing for the first longline vessels to fish at HIMI in 2003 and 2004. This dataset consists of a polygon shapefile representing the sector areas and a map displaying the sector areas. Each polygon has the attributes polygon number and area in square kilometres. The dataset was created in December 2015 using current boundaries as listed in the Quality section of this record.

  • This is data describing acoustically observed krill swarms that was used in the Bestley et al. (2017) paper 'Predicting krill swarm characteristics important for marine predators foraging off East Antarctica' (http://onlinelibrary.wiley.com/doi/10.1111/ecog.03080/full). Abstract of the paper presented here: Open ocean predator-prey interactions are often difficult to interpret because of a lack of information on prey fields at scales relevant to predator behaviour. Hence, there is strong interest in identifying the biological and physical factors influencing the distribution and abundance of prey species, which may be of broad predictive use for conservation planning and evaluating effects of environmental change. This study focuses on a key Southern Ocean prey species, Antarctic krill Euphausia superba, using acoustic observations of individual swarms (aggregations) from a large-scale survey off East Antarctica. We developed two sets of statistical models describing swarm characteristics, one set using underway survey data for the explanatory variables, and the other using their satellite remotely sensed analogues. While survey data are in situ and contemporaneous with the swarm data, remotely sensed data are all that is available for prediction and inference about prey distribution in other areas or at other times. The fitted models showed that the primary biophysical influences on krill swarm characteristics included daylight (solar elevation/radiation) and proximity to the Antarctic continental slope, but there were also complex relationships with current velocities and gradients. Overall model performance was similar regardless of whether underway or remotely sensed predictors were used. We applied the latter models to generate regional-scale spatial predictions using a 10-yr remotely-sensed time series. This retrospective modelling identified areas off east Antarctica where relatively dense krill swarms were consistently predicted during austral mid-summers, which may underpin key foraging areas for marine predators. Spatiotemporal predictions along Antarctic predator satellite tracks, from independent studies, illustrate the potential for uptake into further quantitative modelling of predator movements and foraging. The approach is widely applicable to other krill-dependent ecosystems, and our findings are relevant to similar efforts examining biophysical linkages elsewhere in the Southern Ocean and beyond. This comma separated variable (CSV) file contains the krill swarm data used in: Bestley, S., Raymond, B., Gales, N.J., Harcourt, R.G., Hindell, M.A., Jonsen, I.D., Nicol, S., Peron, C., Sumner, M.D., Weimerskirch, H. and Wotherspoon, S.J., Cox, M.J. (2017). Predicting krill swarm characteristics important for marine predators foraging off East Antarctica. Ecography. The column descriptions are: Depth_mean_m = (units m) mean depth of a krill swarm Date = (YYYYMMDD) observation date (UTC) Time = (HH:mm:ss.ss) observation time (UTC) Lat = (dd.ddddd) latitude Lon = (ddd.ddddd) longitude transect = BROKE West transect number 7 to 11 (see Fig. 1, Bestley et al. 2017) denVolgm3 = (units g wet mass m-3) internal krill swarm density in gram wet mass per cubic metre.

  • Australian fishing vessels involved in exploratory fishing for Antarctic toothfish in East Antarctica under the auspices of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) collected data required under their exploratory fishing permit. Conductivity, temperature and depth (CTD) loggers were attached to bottom longlines sets to collect data while fishing for Antarctic toothfish in Antarctic waters. The data relates to Objective 2 of the research work required: Collect and utilise environmental data to inform spatial management approaches for the conservation of toothfish, bycatch species and representative areas of benthic biodiversity (CCAMLR 2016). Data were collected on two fishing vessels during the austral summers (December to February) of 2015/16, 2016/17 and 2017/18 in CCAMLR Divisions 58.4.1 and 58.4.2. The data were collected with DST CTD (Conductivity, Temperature and Depth Recorder) from Star-Oddi (Conductivity: 13-50 mS/cm, maximum depth: 2400 m). Files were then downloaded with SeaStar and are available in the original data format. Recordings were made at 5 or 10 second intervals for the duration of up to around 24h, recording data throughout the water column while setting the longline and then while stationary on the sea floor. Each deployment has data on time, temperature (degrees C), salinity (psu), conductivity (mS/cm) and depth (m), and is linked to geographical coordinates. Number of deployments: 2015/16: 34 2016/17: 31 2017/18: 75 CCAMLR (2016) Joint research proposal for the Dissostichus spp. exploratory fishery in East Antarctica (Divisions 58.4.1 and 58.4.2) by Australia, France, Japan, Republic of Korea and Spain. Delegations of Australia, France, Japan, Republic of Korea and Spain. Report to Fish Stock Assessment Working Group, WG-FSA-16/29, CCAMLR, Hobart, Australia. Dates and times in the data files are recorded in UTC. Further information is provided in a pdf document in the download file.

  • This research was a manipulative experiment on autoline ling vessels in the New Zealand ling fishery. The vessels were the Janas and the Avro Chieftain. The experiment examined both seabird bycatch data and fish catch data, as well as operational aspects of fishing with integrated weight longline. The data is a little bit complicated and it is essential that any users be familiar with the methodologies in the scientific paper that was published from the work. That will provide a lot of necessary guidance as well as a context for the research. The data covers 2002 and 2003, as indicated on the files. The data submitted includes relevant information of i) seabird by-catch; ii) catch rates of target fish; iii) catch rates on non-target fish. There is replication in some of the data sheets provided. There are headers in each data file that are explanatory.

  • Metadata record for data from ASAC Project 2722 See the link below for public details on this project. Public The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) aims to manage the harvesting of living resources in the Southern Ocean in a manner that is sustainable to the harvested species, dependent species and ecosystem processes. The krill fishery is one of the major fisheries in the Southern Ocean. Application of CCAMLR's policy in management of the krill fishery requires sound scientific information on both krill and krill-dependent (predator) species. This program aims to provide the scientific information on krill predators required by CCAMLR for sustainable management of the krill fishery through research, survey and monitoring activities. Taken from the 2009-2010 Progress Report: Project objectives: The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) aims to manage the harvesting of living resources in the Southern Ocean in a manner that is sustainable to the harvested species, dependent species and ecosystem processes. The krill fishery is one of the major fisheries in the Southern Ocean. Application of CCAMLR's policy to management of the krill fishery requires sound scientific information on both krill and krill-dependent (predator) species. This program of work aims broadly to provide the scientific information on krill predators required by CCAMLR for sustainable management of the krill fishery in the Australian Antarctic Territory against a background of other impacts such as climate change, and compliments separate SOE projects aimed at krill itself. This program is related to the previous multi-year project number 2205 (Adelie penguin research and monitoring in support of the CCAMLR Ecosystem Monitoring Project (CEMP)) but recognises and addresses recent developments in CCAMLR that include (i) the current development of a krill management procedure, (ii) a review of outputs from past CEMP work and recognition of the likely need to re-design CEMP to meet the needs of the new krill management procedure, and (iii) the need to estimate predator consumption of krill as part of the krill management procedure. Although the previous project 2205 focussed on Adelie penguins in the Mawson region exclusively, this new program will include consideration of additional species and regions to allow improvements in both ecosystem monitoring and estimation of krill consumption. The program was approved in 2005 as a multi-year ASAC project with four major sub-programs or projects which have strong methodological and practical cross-linkages and overlap. The projects and their objectives are: (1) Development of cost-effective methods for surveying and monitoring predator populations at the large spatial scales required by CCAMLR, (2) Estimation of the abundance of krill predators in CCAMLR Statistical Areas 58.4.1 and 58.4.2 (which together span the width of the Australian Antarctic Territory), (3) Assessment of spatio-temporal variability in predator performance parameters to enable the design of an effective and efficient monitoring program, and to examine metapopulation dynamics (4) Continuation of selected aspects of project 2205 to (i) improve estimates and understanding of temporal variability and population dynamics and (ii) continue the application of CEMP. We propose to continue these projects in 2008/09 and commence some additional projects. Projects (1) and (2) will be expanded beyond Adelie penguins to include some species of flying seabirds. Additional work related to the AAD's management of the Rookery Islands Specially Protected Area is proposed which would be undertaken in collaboration with the AADs environmental policy section, and aims to assess the status of the Southern Giant Petrel. It would be undertaken in conjunction with planned surveys of Adelie penguins and some flying seabird species in the Rookery Islands (project 2). Details of the work will be outlined in a separate proposal submitted by the AAD environmental policy section. A additional project is related to an IPY approved project focussing on Adelie penguins as indicators in the Southern Ocean. The objective of this new project is to co-ordinate some aspects of the work of Adelie penguin researchers around Antarctica to improve understanding of broad-scale processes in the Southern Ocean. A planning meeting in May 2007 had to be postponed until September 2007 and consequently it is not yet possible to outline the details of this project. We will provide project details as soon as possible after the September 2007 meeting and request that a late submission be accepted for this project. Progress against objectives: (1) Implementation and further development of cost-effective methods for surveying and monitoring predator populations at the large spatial scales required by CCAMLR. Camera technology has been developed and is now being used to monitor Adelie penguin populations on several islands in the Mawson and Davis areas. Methods for cost-effective development of regional population size have also been developed and applied in the Mawson and Davis areas. Flying seabirds have been incorporated in the monitoring program by developing and implementing monitoring methods of snow petrel on Bechervaise Island. (2) Estimation of the abundance of krill predators in CCAMLR Statistical Areas 58.4.1 and 58.4.2 (which together span the width of the Australian Antarctic Territory). Aerial surveys were undertaken of Adelie penguin populations in the Vestfold Hills and Rauers Islands. Reconnaissance surveys of Adelie penguin distribution were conducted by the CASA aircraft between Casey and Mirny. Ground surveys of Adelie penguin populations were undertaken in the Mawson region (3) Assessment of spatio-temporal variability in predator performance parameters to enable the design of an effective and efficient monitoring program, and to examine metapopulation dynamics. Population surveys and the use of cameras at multiple sites in the Mawson area are providing data on Adelie penguin meta-population dynamics. (4) Continuation of selected aspects of project 2205 to (i) improve estimates and understanding of temporal variability and population dynamics and (ii) continue the application of CEMP. Measurement of Adelie penguin population size, foraging trip duration, breeding success and survival at Bechervaise Island continued in 2009/10 (5) Assessment of the winter foraging distribution of Adelie penguins. Satellite trackers were successfully deployed on 15 fledgling Adelie penguins.

  • The attached file details the workflow for the processing and analysis of active acoustic data (Simrad EK60; 12, 38, 120 and 200 kHz) collected from RSV Aurora Australis during the 2006 BROKE-West voyage. The attached file is in Echoview(R) (https://www.echoview.com/) version 8 format. The Echoview file is suitable for working with fisheries acoustics, i.e. water column backscatter, data collected using a Simrad EK60 and the file is set-up to read 38, 120 and 200 kHz split-beam data. The file has operators to remove acoustic noise, e.g. spikes and dropped pings, and operators for removing surface noise and seabed echoes. Echoes arising from krill are isolated using the ‘dB-difference’ method recommended by CCAMLR. The Echoview file is set-up to export the results of krill echo integration as both intervals and swarms. Full details of the method are available in Jarvis et al. (2010) and the krill swarms methods are described in Bestley et al. (2017).

  • Statistical areas, subareas and divisions are used globally for the purpose of reporting fishery statistics. CCAMLR's Convention Area in the Southern Ocean is divided, for statistical purposes, into Area 48 (Atlantic Antarctic) between 70oW and 30oE, Area 58 (Indian Ocean Antarctic) between 30o and 150oE, and Area 88 (Pacific Antarctic) between 150oE and 70oW. These areas, which are further subdivided into subareas and divisions, are managed by CCAMLR. A global register of statistical areas, subareas and divisions is maintained by FAO http://www.fao.org/fishery/area/search/en. CCAMLR Secretariat (2013)

  • A meta-analysis was undertaken to examine the vulnerability of Antarctic marine biota occupying waters south of 60 degrees S to ocean acidification. Comprehensive database searches were conducted to compile all English language, peer-reviewed journals articles and literature reviews that investigated the effect of altered seawater carbonate chemistry on Southern Ocean and/or Antarctic marine organisms. A document detailing the methods used to collect these data is included in the download file.

  • This integrated stock assessment for the Patagonian toothfish (Dissostichus eleginoides) fishery at the Heard Island and the McDonald Islands in CCAMLR Division 58.5.2, with data until end of July 2015, is based on the best available estimates of model parameters, the use of abundance estimates from a random stratified trawl survey (RSTS), longline tag-release data from 2012-2014 and longline tag-recapture data from 2013-2015, and auxiliary commercial composition data to aid with the estimation of year class strength and selectivity functions of the trawl, longline and trap sub-fisheries.All model runs were conducted with CASAL version 2.30-2012-03-21 (Bull et al. 2012). The assessment model leads to an MCMC estimate of the virgin spawning stock biomass B0 = 87 077 tonnes (95% CI: 78 500-97 547 tonnes). Estimated SSB status in 2015 was 0.64 (95% CI: 0.59-0.69). Using this model, a catch limit of 3405 tonnes satisfies the CCAMLR decision rules. Similarly to the 2014 assessment, the projected stock remains above the target level for the entire projection period.