Introduction
It covers how to report on performance for target species and the rest of the ecosystem. In the longer term, this will involve the explicit recognition of the role of social and economic aspects within the decision-making process of fisheries management (including resource allocation).
Overview
Catch and effort statistics have been collected for EEA fisheries since the beginning of fishing in 1963. The supply impact of by-catch discards from EEA fishing was taken into account.
Background on the Exmouth Gulf Prawn Fishery
DESCRIPTION OF THE FISHERY
Since the fishery began in 1963, catch and effort statistics have been collected for EGP fisheries. There is very limited existing information on the level and nature of bycatch in EGP fisheries, and on bycatch at the start and other stages in the history of the fishery.
BIOLOGY OF WESTERN KING PRAWNS
Juvenile western king shrimp burrow into the substrate (usually shallow sandbanks) during the day. While in nurseries, western king prawns are nocturnal and forage at night with small animals and detritus.
BIOLOGY OF BROWN TIGER PRAWNS
As for western king prawns, when tiger prawns mate, the male must be hard shelled and the female must be soft shelled (newly moulted). The female's ovary develops rapidly and the eggs are released into the water before the female molts again.
BIOLOGY OF ENDEAVOUR PRAWNS
After hatching, the larvae, called nauplii, swim freely in the water column, but they do not feed. During the nauplii stages, the larvae use stored food from the egg, completing a series of six molts before developing into the next larval stage (Penn and Stalker, 1979).
BIOLOGY OF BANANA PRAWNS
MAJOR ENVIRONMENTS
Physical environment
The low abundance of seagrass in the area distinguishes it from the nursery areas that support juvenile tiger prawns elsewhere in Australia, where seagrass beds are of greatest importance (Penn, 1988; Hill and Wassenberg, 1993; Watson and Turnbull, 1993). The average ambient water temperature in Exmouth Gulf varies from 30°C in summer (January to March) to as low as 17°C in the winter months (June to August) (Harris, 2000).
Economic environment
Tropical cyclones with wind speeds in the 40-50 knot range occur every three to five years, with less intense systems occurring annually from January to March. These cyclonic events have been shown to have large positive and negative impacts on tiger shrimp stocks in the Gulf, depending on the month they occur and their track through the area (Penn and Caputi, 1986).
Social environment
The southeastern and eastern areas of the bay are hypersaline (35-55‰) nursery areas for the native tiger shrimp population (White, 1975a). Together with the physical geography of Exmouth Gulf, the minimal river flow entering the bay creates a relatively stable hydrological environment (Penn and Caputi, 1985).
Outline of reporting process
SCOPE
OVERVIEW
A summary assessment of the fishery was completed, including an action plan of activities to be undertaken to ensure that acceptable levels of performance can continue or, where necessary, improve fishery performance.
ISSUE IDENTIFICATION (COMPONENT TREES)
Stakeholders present at this meeting included commercial industry, recreational fishers, environmental groups, local government, Environment Australia, Department of Environmental Protection, Department of Fisheries staff and an independent moderator (full list of participants in Appendix A3.1) .
RISK ASSESSMENT/PRIORITISATION PROCESS
Only matters of sufficient risk (moderate, high and extreme) – those requiring specific management measures – need to complete a full performance report.
COMPONENT REPORTS
Nevertheless, the rationale for classifying issues as low or even negligible risk was also documented and is part of the ESD report.
APPLICATION TO MEET EPBCA REqUIREMENT
OVERVIEW TABLE
Issue Objective Developed Measured Performance Indicator Current Performance Measure Strong Performance Guidelines Covered Actions RETAINED TYPES (cont. errors Non- Negligible RiskN/AN/AN/AN/A1.1.8Review the risk in the next major assessment in 5 years.FormanceRobustnessGuidelines CoveredActions NON-CONSERVED SPECIES (cont'd) 5.2.1.6 Flatback turtles Non- Negligible risk.
Performance reports
RETAINED SPECIES
Primary species
- Tiger prawns
- King prawns
- Endeavour prawns
- Banana prawns
Summary: The current analysis (Figure 15) of the king prawn parent stock is at or above the agreed reference point. Catch may not be an index of abundance due to non-targeting of the species. Maintaining productivity of the banana shrimp stock by ensuring that recruitment levels are only affected by environmental fluctuations, not spawning stock levels.
Summary: The current analysis (Figure 17) of the banana shrimp catch indicates that the parent stock is at an acceptable level.
By-product species
- Coral prawns
- Blue Swimmer crabs
- Squid and cuttlefish
- Sharks
- Bugs
- Cobia
- Cods
- Mackerel
- Nor-west snapper
- Other species
Historic catch (tonnes) of coral shrimp and total rated total effort in the EGP fishery. The fishery managed by Exmouth Gulf Prawn accounts for only a very small portion of the total catch of blue swimmer crabs. In terms of impact on squid and squid farming stocks, the impact of EGP fishing is considered negligible.
The EGP fishery catches and retains other species such as curiosities (shells and fish, etc.) in very small numbers.
NON-RETAINED SPECIES
Captured in nets
- Protected species – seasnakes
- Protected species – Syngnathids
- Protected species – Leatherback turtles
- Threatened/listed species – Green turtles
- Threatened/listed species – Loggerhead turtles
- Threatened/listed species – Flatback turtles
- Threatened/listed species – Hawksbill turtles
- Discarded fish
- Invertebrate species
There have been no reported catches of leatherback turtles in gear for the EGP fishery during the 40-year history of the Fishery. There have been very few reported catches of green turtles on beam gear during the 40 year history of the fishery. However, there have been very few reported catches of flat turtles on trawl gear during the 40-year history of the fishery.
There have been no reported catches of hawksbill turtles in the trawl gear during the fishery's 40-year history.
Interaction but no capture
- Protected species – Dugongs and cetaceans
- Protected species – Leatherback turtles
- Threatened/listed species – Loggerhead turtles
- Threatened/listed species – Green turtles
- Threatened/listed species – Flatback turtles
- Threatened/listed species – Hawksbill turtles
Leatherback turtles are considered a protected species under Commonwealth law and are found in Exmouth Bay. Green turtles are considered a vulnerable species under Commonwealth law and are native to Exmouth Gulf waters. Flatback turtles are considered a vulnerable species under Commonwealth law and are found in Exmouth Gulf.
Hawksbill turtles are considered a vulnerable species under Commonwealth law and are found in Exmouth Bay.
Impacts from removal or damage to the environment
- Prawns
- By-product species
- All retained and non-retained species
- Impact to the mud/sand habitat
- Impact to the coral/sponge habitat
- Impact to the macro-algal habitats
To maintain an acceptable level of impact on the mud/sand habitat in Exmouth Bay. Percentage of mud/sand habitat in the Exmouth Bay region that is trawled. Trawled areas of Exmouth Bay are estimated to be approximately % of all waters in Exmouth Bay (1.km).
It is currently estimated that trawling occurs in over 35% of the mud/sand habitat in Exmouth Gulf.
Addition of materials to habitat
- Discarding fish
The amount of discards per fishing season will be monitored as a measure of performance against the target. Reduction in the ratio of discards to target catch from levels obtained before the introduction of bycatch reduction devices. To establish this data, the amount of target catch will be required in addition to the amount of discard (as provided above).
Department of Fisheries Research Division to monitor the amount of discards and the proportion of bycatch on a five-year basis.
General impacts on the environment
- Creation of turbidity from trawling
- Translocation
GOVERNANCE
- Department of Fisheries – Management
- Management effectiveness (outcomes)
- Management arrangements
- Compliance
- Allocation among users
- Department of Fisheries – Legal arrangements
- OCS arrangements
- Department of Fisheries – Consultation
- Consultation
- Department of Fisheries – Reporting
- Assessments and reviews
A clear description of the management unit – The management unit is explicitly described in the "Fishery Statement" section of the EGP Plan. An observational review is maintained by the Department of Fisheries and EGPMAC on the functionality of the management arrangements. The Minister or ED (or the Department on their behalf) complies with the consultation requirements of the FRMA and the Management Plan.
Current: Report annually to Parliament and the community on the status of the fisheries.
Bibliography
Temporal and spatial distribution of the brown tiger prawn Penaeus esculentus (Haswell), in Exmouth Bay, Western Australia. Stock establishment-recruitment relationships and management of the Penaeid Prawn fishery in Shark Bay, Western Australia. A study of the effects of shrimp fishing on benthic communities in two South Carolina sounds.
Population dynamics of the tiger prawn Penaeus esculentus in the Exmouth Gulf Prawn fishery and implications for the management of the fishery.
Appendices
Terminology
Figures
Attendees lists
David Adams, Exmouth RFAC Errol Sporer, Ministry of Fisheries Felix Correia, Correia Holdings Pty Ltd. Heidi Grief, Department of Fisheries Hamish Ch'ng, Industry Shark Bay Scallop Jenny Shaw, Department of Fisheries Jim Penn, Department of Fisheries Jo Bunting, Department of Fisheries Keith Shadbolt, Denham RFAC Les Moss, Shire of Shark Bay Lindsay Joll, Department of Fisheries Mark Hook, Shire of Shark Bay Martin Holtz, Recfishwest. Mervi Kangas, Ministry of Fisheries Nic Dunlop, Conservation Council of WA Paul Bowers, Aboriginal Lands Trust.
Rod Berg, kontor for generalrevisor Shane O'Donoghue, Department of Fisheries Stephen Hood, Industry - Exmouth Gulf Prawn.
National ESD consequence levels and likelihood definitions for
Minor Target/Not Retained: A detectable but small effect on population size but not on population dynamics. The catch and catch area of this fishery are small compared to the known range (< 20%). Moderate target/unconserved: level of full exploitation where long-term recruitment/dynamics are not adversely affected.
Serious target/not retained: Affects recruitment levels of stock/ or their ability to increase by-product: Other not retained: No information is available on the relative area or.
Acronyms
Research
Project -Exmouth Gulf PrawnsRes.GroupLinkGap1970s1980s1990s Kings ReproductionFWA3 GrowthFWA3 (x) CR(x) CR Habitat RequirementsFWA3 MigrationFWA(x) CR(x) CR Natural MortalityFWA Catch ConventionFWA Efforts Reproduction 3FWAF 3 Prohibition Reproduction 3FWAF 3 Prohibition Reproduction ReproductionFWA3 GrowthFWA3 Rain -recruitment-catch FWA3 ENVIRONMENTAL MANAGEMENT Bycatch MonitoringFwa3 3 FRDC/CR FRDC/CR BiodiversityFWA/Museum (X) FRDC (X) FRDC Stock Enhancement/Aquaculture Modeling RecruitmentCSIRO/FWA3 Enhancement DC ( x) FRDC(x) FRDC Juvenile habitat survey(s)CSIRO FRDCx FRDC Socio Economy 1. Tools, Vessels and Vessel Design Tools Developmenti/FWA Bifang Deduction Device/FWA3 3 FRDC/CR FRDC/CR Net Configurations - Quadi/FWA3 3 3 x Bison Boardsfwa3 Catch POSSIBLE x frdcx frdc vmsfwa boundary (not trawl) "fixing" FWA Research Group Key: FWA- Fisheries WA, I – Industry, CSIRO QWA, CSIRO QWA, CSIRO QWA Key: - completed, X committed, (X) proposed but not approved/committed, R review Funding source: CR- cost recovery, FRDC- Fisheries Research and Development Corporation.
Stock monitoring surveys in Exmouth Gulf
In addition to observers collecting data on commercial vessels during normal fishing operations, experimental trials were also conducted in 2000 on different types of grids for shark bay shrimp fishing, scallop and Exmouth Gulf shrimp. The categories recorded for each side (port and starboard) (side with BRD noted)) were; total weight or volume of by-catch (small fish, crustaceans, echinoderms and molluscs), catch of target species (king, tiger, endeavour, coral shrimp and scallops) and numbers of sharks, rays, sea snakes, sponges and turtles. Shark Bay also recorded numbers of pink snappers (Pagrus auratus) and their size composition for some trawls.
Bycatch volume was recorded for all other small finfish and invertebrate species retained by the trawl, with the exception of large animals.
Materials supplied to Environment Australia against their
A full description of the management arrangements for the commercial fishery is contained in the attached management plan. A number of monitoring programs currently in place for EGP fisheries also provide relevant information on by-product species. There have been no reported catches of leatherback turtles in gear for the EGP fishery spanning the 40-year history of the fishery.
A formal risk assessment was completed (see section 5.3 for details) for each of the identified issues relevant to the EGP fishery (see the issue tree).
Recommendations and approval from EA
