Adult grooved tiger prawns (Penaeus semisulcatus) were caught in prawn trawls during one transect of the Gulf of Carpentaria on the FRV Southern Surveyor. The catches were used to assess offshore migration of the species. Data collected include length frequency, sex and gonad stage. Data were collected using 39 paired Florida Flyer trawls centred on 6nm grids across approximately 13 sites. The sites are spaced some distance apart along the cruise track (a transect from Weipa to N Groote and back to Weipa). The AusTED and standard codend were compared in these trawls, and the same data were also to be used monitor the distribution of Penaeus semisulcatus across the Gulf. Problem shots were retrawled when possible to meet the experimental design. Nine were abandoned due to lack of time.

The objectives of this project were: To design and implement a survey program to augment the historical survey data used for species split with contemporary, well-targeted and spatially precise data. This survey to be trialled in 2002-3 and confirmed in 2003-4. To establish a protocol so that such surveys can be quickly designed and implemented on an ongoing monitoring basis. To develop further the species split methods first proposed in FRDC 98/109 so that they can be used confidently in any new stock assessments. To re-examine the historical survey data as part of the strategy for the above and to report, particularly on the value of size class information for this purpose. To investigate and report on the potential use of electronic logbooks for enhancing the precision of stock assessment of Tiger prawn species, particularly on a spatially local scale. To investigate and report on the use of size class data for gaining some information on recruitment patterns for the stock assessment.

Adult prawn species, size, sex, reproductive stage, moult stage, and parasites were measured at 20 stations in Albatross Bay, Gulf of Carpentaria. Sampling was carried out monthly, around the new moon period, between March 1986 and May 1992. The projects objectives were: - To carry out a trawl survey of prawn species distribution, size distribution, population density and reproductive status in the study area - To carry our sampling for larval prawns at selected stations. - To sample for phytoplankton species composition and chlorophyll a levels at selected stations.

This data was performed as part of the Stock Recruitment Relationships project. The objectives were to collect more information on fishing effort at a smaller spatial scale (GPS systems had recently been introduced), to determine the degree of aggregation of fishing effort, and to determine how try net gear may alter fishing effort. CSIRO staff performed the data collection from commercial vessels, and measured and identified prawns - collected at night - from try shots. Prawns were sorted by species and sex, with each prawn individually measured. Ripe remales were given a gonad stage (1-5). No weight information was collected. Bycatch was identified and counted.

Prawn larval densities were calculated from stepped oblique bottom to surface plankton tows, deployed during monthly cruises carried out at twenty-one stations in Albatross Bay, Gulf of Carpentaria. Cruises were undertaken between March 1986 and April 1992. Penaeid prawn counts were recorded to species level (Penaeus spp.) for all observed larval stages. Sampling used a stepped-oblique tow, using a 0.5 x 0.5 square metre frame with 140-142 micron mesh. Salinity-temperature profiles were also recorded during the cruise.

Plankton samples were taken monthly at Groote Eylandt, Gulf of Carpentaria. Numbers and densities of plankton were measured and prawn post-larval data were collected.

Total zooplankton biomass levels were calculated from stepped oblique bottom to surface plankton tows, deployed during monthly cruises carried out at twenty-one stations in Albatross Bay, Gulf of Carpentaria. Cruises were undertaken between March 1986 and April 1992. Total zooplankton biomass were calculated as grams dry weight. Sampling used a stepped-oblique tow, using a 0.5 x 0.5 square metre frame with either a 140-142 micron mesh (sampler_code = 'A'), or a 250 micron mesh (sampler_code='E')

Prawn larval densities were calculated from stepped oblique bottom to surface plankton tows, deployed during monthly cruises carried out between March 1986 and April 1992, at twenty-one stations in Albatross Bay, Gulf of Carpentaria. Penaeid prawn counts were recorded to genus level (Penaeus spp.) for all observed larval stages. Salinity-temperature profiles were also recorded during the cruise.

This dataset is the result of a series of trawl surveys carried out aboard F.V. Maxim between August 1983 and March 1985 in the NW Gulf of Carpentaria, north of Groote Eylandt. The main reference is by Somers et al (1987) - see References link below. It details the gear, methods, study area, etc. The data collected included abundance and size composition of the commercial species of penaeids together with data on hydrology at the time of sampling, across 60 stations. Reproductive stage, moult stage, and parasites were also recorded. Cruises were carried out every four weeks centred around the new moon period.