Fishery Status Reports 2006
Dept. of Primary Industry, Fisheries and Mines.
Fishery reports; Reports; PublicationNT; Fishery report ; no. 87
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Fishery resources -- Northern Territory -- Periodicals; Fisheries -- Northern Territory -- Periodicals; Shark fisheries -- Northern Territory -- Periodicals; Mackerel fisheries -- Northern Territory -- Periodicals; Crab fisheries -- Northern Territory -- Periodicals; Giant perch fisheries -- Northern Territory -- Periodicals; Lutjanidae fisheries -- Northern Territory -- Periodicals
Dept. of Primary Industry, Fisheries and Mines
Fishery report ; no. 87
Check within Publication or with content Publisher.
F I S H E R Y S T A T U S R E P O R T S 2 0 0 6 62 Non-retained Species Conventional crab pots, which are used to varying degrees by all sectors, are constructed from wide-mesh metal sheet and are highly selective towards adult mud crabs. Hence, the catch of non-target species is minimal. The aggressive nature of mud crabs may also deter other animals from entering pots. Apart from undersized (or unmarketable) mud crabs, which must be released, other by-catch species such as blue swimmer crabs, cod and catfish may or may not be released. Blue swimmer crabs are often kept for consumption by all sectors, whereas cod and catfish, which are typically released by recreational fishers, are used as bait by commercial fishers. Indigenous fishers target the same crab species as the other sectors, but their preferred harvest methods of hand collection or spear virtually eliminates by-catch. Threatened Species Interaction There were no reported interactions between threatened species and the Mud Crab Fishery in 2006. Ecosystem Impact The Mud Crab Fishery has minimal impact on the ecosystem due to passive fishing methods that effectively target large mud crabs. DEW has reviewed the impacts of the fishery on the ecosystem and has determined that crocodiles, turtles and sharks may feed on mud crabs. However, the current level of mud crab harvest is unlikely to significantly impact on these species. A study by Hay et al. (2005) documented the relative abundance of mud crabs (Scylla serrata) in selected coastal habitats around northern Australia and serves as a comparative tool for similar areas if subjected to natural or anthropogenic disturbance. Social Impact Commercial mud crab fishing operations and processing provide direct employment and support a service industry which supplies gear and consumables to crab fishers, services their equipment and provides freight services. Crabbing operations may also benefit landholders, as crabber camps may incur access or permit costs and camping fees. Mud crabbing is also a popular recreational pastime as there is good access to the resource close to population centres. Whilst difficult to quantify, money spent by recreational fishers in the pursuit of mud crabs contributes to employment in the FTO, tackle and hospitality sectors. Economic Impact In 2006, the NT commercial mud crab catch was 266 tonnes, valued at about $4.73m. The recreational sector also contributes to the NT economy, particularly, the service and tackle industries. Stock Assessment Monitoring A mud crab monitoring program has been in place since the early 1990s. Between 100 and 200 crabs (contingent on availability) are sampled from several regions (i.e. the Roper River, the Adelaide River, Blue Mud Bay and the Borroloola area) on a monthly basis and important information such as carapace width, weight, sex and mating success are collected. Time series analysis of carapace width data collected from the commercial fishery reveals a small decline in the mean size for both male and female crabs harvested in most regions. Such trends are often observed in harvested stocks, thereby necessitating the use of minimum size limits to ensure that a sufficient proportion of the stock has the opportunity to reproduce.
Aboriginal and Torres Strait Islander people are advised that this website may contain the names, voices and images of people who have died, as well as other culturally sensitive content. Please be aware that some collection items may use outdated phrases or words which reflect the attitude of the creator at the time, and are now considered offensive.
We use temporary cookies on this site to provide functionality.
You are welcome to provide further information or feedback about this item by emailing TerritoryStories@nt.gov.au