A short explanation of what fisheries science is

Australia’s wild catch commercial fisheries are of economic and social importance. They provide employment and income to thousands of people, make public resources available to those that can’t catch their own fish and can be a drawcard for tourism in some coastal areas. Australian fisheries are diverse in the areas fished, species landed and fishing gears used.

Management of Australian fisheries is some of the best in the world. Over 90% of our catch comes from sustainable stocks with those judged not currently sustainable, being mainly managed through re-building strategies.

Commercial fishing occurs in estuaries and bays, on the continental shelf and oceanic waters throughout Australia’s Economic Exclusion Zone as well as on the high seas. Hundreds of different species are landed, ranging from sea cucumbers to prawns and tuna. These are sold in markets, stores and restaurants around Australia and exported. Fishing gears used range from hand harvest to large offshore trawlers.

In 2019-20, Australian seafood production (including aquaculture) had a gross value of $3.11 billion.

Aboriginal and Torres Strait Islander peoples’ have been sustainably fishing in Australian waters for tens of thousands of years. For many contemporary Indigenous communities, fishing is both sustenance and cultural connection to their ancestors, oceans and inland water ways that form part of their country. Fishing by Aboriginal and Torres Strait Islander peoples’ covers customary, recreational and commercial.

Indigenous ecological knowledge is increasingly being seen as a valuable resource for land and water managers around Australia. Traditional burning is a great example of how Indigenous fire management practices are becoming widely recognised as an important and effective land management tool. In fisheries also, traditional knowledge is recognised as an essential component of good management.

In many parts of Australia, Aboriginal and Torres Strait Islander peoples’ have important rights to access and manage their traditional fisheries without regulation. These rights have been secured with the help of native title.

Recreational fishing is one of the largest outdoor activities in Australia. It provides social benefits and is part of life for over three and a half million Australians of all ages and socio-economic groups. In addition, recreational fishing provides direct economic benefits to the wider Australian economy and the economy of specific regions and towns around Australia.

Recreational fishing in Australia ranges from casting a line of a jetty to serious game fishers. Mostly, recreational fishing in Australia is undertaken for leisure but there are a range of other reasons, one of which is the provision of food.

The future of recreational fishing and the quality of the fishing experience is reliant on healthy and sustainable fish stocks. Each Australian state has a peak body that represents recreational fishers and a component of their mission statement is to work with federal and state governments to encourage sustainable fisheries management.

The last time a survey was done in 2001, the value of recreational fishing to the Australian economy was estimated to be $1.85 billion.

Fisheries science endeavours to understand the biology of fish and the state of fish stocks. It draws on a range of disciplines including marine and freshwater biology, oceanography, physics, chemistry and mathematics. One of the main aims of fisheries science is to provide fisheries managers with quality data on which they can make informed decisions about how best to manage fish stocks. Data about fish stocks is collected through surveys and monitoring. Fisheries science work is undertaken by fisheries agencies (both state and commonwealth), government science organisations (e.g. CSIRO and the Australian Antarctic Division etc), universities, non-government organisations and independent research providers.

There are a range of different survey and monitoring tools used to collect data. Fisheries data is split into fishery-dependent data and fishery-independent data. Fishery dependent data is collected directly from a fishery of fisher and includes creel surveys, boat ramp cameras, logbooks, fishery observers and port sampling. Fishery-independent data is collected outside of normal fishing and includes baited remote underwater video surveys, tagging experiments, trawl surveys, dive surveys and experiments.

It’s important to make sure that results from fisheries science research is communicated to stakeholders and the public.  This ensures the data is used to best manage Australia’s fisheries and provide the public with the confidence that the fish they buy comes from sustainable stocks.

Understanding fish biology is essential to good fisheries management because it gives information about the productivity of a fish stock and informs the most sustainable strategy for managing that stock. Fisheries scientists collect a wide range of information on fish biology that is used in fisheries management. This information includes:

• Stock structure – the division of local sub-populations of fish that don’t mix or breed with other stocks.
• Age and growth – these can be estimated using ear bones or other hard parts, or through tagging experiments.
• Reproduction – including at what age and length fish reach maturity, how many eggs they produce and how that changes with fish size and how, when and where the fish breed.
• Recruitment – the entry of young fish into the fished component of the stock through growth or movement.  It can be important to understand what effects recruitment levels such as, the number of mature fish in the stock and environmental variables.
• Mortality – total mortality is the rate that fish are killed both from natural causes (natural mortality from predation, old age, disease) and from fishing (fishing mortality).

Fisheries management sets out the rules for sustainable fishing. These rules can apply to specific species, whole fisheries, fish stocks and ecosystems. Fisheries management is a process of decision-making, allocation of resources and formulation and implementation of regulations or rules. These rules govern fisheries activities to ensure the continued productivity of the resources and the accomplishment of other fisheries objectives.

The tools used to manage fisheries generally include the following three components:

• Science and research that informs fisheries management.
• Regulations and other management arrangements that set-out fisheries rules.
• Enforcement and monitoring to enusure the rules are followed.

Fisheries management is undertaken by government agencies but relies on the input of stakeholders such as fishers and environmental NGOs as well as external scientists.

Monitoring fisheries to collect data is an essential component of fisheries management. Fisheries managers are using the data to monitor fishery status, for example changes in catch rates, recruitment, biomass and a range of other important indicators. Data collected are used to make informed management decisions in setting fisheries rules such as catch limits, effort limits, minimum lengths, and fishing gear that can be used.

Common types of data collected include catch weight or number, the amount of effort used (e.g. number of hooks used or hours fished), the size and age of fish caught, the amount of bycatch and interactions with protected species.  These data can be collected by fishermen in logbooks, by observers working on fishing boats, in ports or undertaking creel surveys, during scientific surveys or using electronic monitoring such as video cameras and vessel monitoring systems (VMS).

Stock assessments are undertaken to check that stocks are being fished sustainably, both biologically and economically.  From a biological point of view, stock assessments generally address two questions about a fish stock:

1. Is the size of the fish stock (for example the biomass) above a level that is considered overfished?
2. Will the current levels of fishing cause the stock to become overfished?

Stock assessment methods are many and varied and the type of method used largely depends on the amount and type of data available. The amount of data available for a species (or stock) is often related to the value of that stock and the risk posed to it by the fishery. The more quality data available, the more complex the stock assessment can be, and the more confidence you can have in its results.  The results of stock assessments are used in harvest strategies to compare indicators against target reference points (the point you want the fishery to be) and limit reference points (the point at which the risk to the stock is too high).

A harvest strategy is an agreed process used to manage a fishery. The elements of a harvest strategy include what and how data is collected, how the data is assessed, rules for what happens if indicators hit certain levels and the management actions that are intended to achieve agreed ecological, economic and/or social objectives.  A havest strategy clearly describes what is considered a ‘healthy’ or sustainable fish stock, what needs to be measured to see if the fish stock is healthy, and what intervention needs to be taken if the stock is considered unhealth.  Harvest strategies are transparent and consistent decision-making frameworks that give stakeholders an understanding of how fisheries will be managed.

Governments use a range of approaches to make sure fisheries are sustainable including setting rules, collecting information and making sure the rules are being followed. Compliance and enforcement aim to effectively deter illegal fishing.  Activities undertaken to ensure compliance and enforcement include:

• Communication and education is used to make sure people know the fishing rules, demonstrating commitments to enforcing regulations, reducing the misconception by offenders that they won’t be caught, increase understanding of the impacts of non‑compliance on fisheries sustainability and industry viability, and increase willingness and capacity to comply with the rules.
• General deterrence is used to encourage compliance by providing a high visual presence.
• Using a targeted risk-based compliance approach allows enforcement agencies to put their efforts into areas when and where they will be most effective.
• Maintenance ensures that previously significant risks do not re-emerge.  Examples include quota reconciliation, fishing/navigating in closed areas, bycatch mishandling, failing to report Threatened, Endangered and Protected (TEP) Species Interactions, and compliance with Vessel Monitoring Systems (VMS) and e-monitoring requirements.