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  • Business structure and costs for Southern Rock Lobster fisheries in Tasmania including fixed (vessels, infrastructure) and variable (bait, fuel, ports) costs.

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    Southern Rock Lobster (Jasus edwardsii) that are about to moult or have recently moulted have reduced market value due to higher mortality in live transport, higher cannibalism and lower meat recovery. Limiting the landing of softer shelled lobsters is desirable to maintain product quality. The effects of several factors on durometer readings were evaluated: sex, temperature (ambient plus elevated 3°C), location (from around the coast), and size (carapace length). Individuals were collected across two regions South Australia and Tasmania.

  • The movement and behaviour of the Southern Rock Lobster (Jasus edwardsii) was monitored using a radio acoustic telemetry systems at two sites in eastern Tasmania.

  • Describes the database used for storing Southern Rock Lobster (Jasus edwardsii) biological data collected by observers on commercial boats and dedicated research trips incorporating information on sex, length, weight, damage, reproduction, bycatch, protected species interaction, location, depth, tagging and equipment type.

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    To test if the carapace length of lobsters changes during cooking, 21 legal-sized southern rock lobsters were collected in pots from Alum Cliffs, south-eastern Tasmania, Australia in October 1999 (42.95±S 147.35±E). The sample consisted of 7 female and 14 male lobsters ranging in carapace length from 106 mm to 153 mm (mean 120 mm). Each animal was abdominally tagged using individually marked t-bar tags (Hallprint T-bar anchor tag, TBA1; Hallprint Pty Ltd, 27 Jacobsen Crescent, Holden Hill, SA 5088, Australia). The carapace length of all lobsters were measured five times to the nearest 0.1 mm in a random manner, before and after processing. This repeated measurement of all specimens in random order was intended to evaluate measurement error. Processing was typical of that used commercially and involved killing the lobsters in fresh water before cooking in pre-boiling salted water for 12 minutes.

  • Southern Rock Lobster (Jasus edwardsii) biological data collected by observers on commercial boats and dedicated research trips incorporating information on sex, length, weight, damage, reproduction, bycatch, protected species interaction, location, depth, tagging and equipment type.

  • Using a telephone/diary survey methodology information about recreational fishing activity for rock lobster and abalone in Tasmania is monitored over a fishing season, with surveys conducted biennially. Information reported includes: date, location (fishing regions), method (pot, ring, dive), target species and catch (numbers of lobster and/or abalone). Sampling is linked to the recreational licensing database, managed by the state government.

  • The spatial extent of the long spined sea urchin, Centrostephanus rodgersii, was estimated by divers using underwater visual census methods to survey rocky reef habitats at 13 regions along Tasmania's east coast (between Eddystone Point and Recherche Bay). Within each region 3 subsites were surveyed, and within each subsite 4 belt transects were surveyed. Divers recorded depth, percent substrata type, percent C. rodgersii barrens habitat; abundance of urchins (C. rodgersii and H. erythrogramma), rock lobster (J. edwardsii) and abalone (H. rubra). Divers also recorded algal cover (estimated), C. rodgersii barrens and substratum type using set categories (see below).

  • Predation mortality rates of blacklip abalone (Haliotis rubra) were estimated under several different conditions using a range of manipulative experiments. Abalone mortality rates were estimated from tethering experiments inside the Maria Island Marine Reserve (MIMR) and at an adjacent site where predators, including southern rocks lobster (Jasus edwardsii) were in low abundance, due to fishing. Estimates of abalone mortality directly attributed to rock lobsters were gained from manipulative experiments inside the MIMR and in an aquarium experiment at the Tasmanian Aquaculture and Fisheries Institute facility at the Marine Research Laboratories.

  • Mortality rates of the sea urchin Heliocidaris erythrogramma where estimated under experimental conditions to determine the importance of natural and predation mortality in structuring sea urchin populations. Data was obtained from tethering, tagging and caging experiments at four sites within Mercury Passage and the Derwent Estuary in eastern Tasmania.