Proposals for community discussion on the future management of Pink Snapper fishing in Cockburn Sound and surrounding waters.
INTRODUCTION
MAKING A SUBMISSION
BACKGROUND INFORMATION
- C URRENT PINK SNAPPER SPAWNING CLOSURE IN C OCKBURN S OUND
- T HE IMPORTANCE OF C OCKBURN S OUND AS A PINK SNAPPER SPAWNING AREA
- R ECREATIONAL FISHING – CATCH AND EFFORT
- C OMMERCIAL CATCH DATA
Research has shown that 92% of pink snapper collected in Cockburn Sound are 7 years or older (Wakefield, unpubl.). This contrasts with the breeding stock in the capital waters outside Cockburn Sound, where the majority of fish are 3 to 7 years old (Wakefield, unpubl.). The average size of fish and the size of the spawning aggregation indicate that Cockburn Sound is an important spawning ground for pink snapper in the lower west coast zone of the fishery.
Providing additional protection for Cockburn Sound spawning aggregation raises the question of the relationship with the stock in the adjacent oceanic areas. Data on boat-based recreational catches and fishing effort for Cockburn Sound and Owen Anchorage were first collected in a 12-month survey of coastal waters from Augusta to Kalbarri during 1996/97. The 1996/97 survey estimated the recreational catch at 20 tonnes for the region, the majority of which was recorded as being taken outside Cockburn Sound.
This survey was conducted during daylight hours and may have missed a significant proportion of the pink snapper catch in Cockburn Sound, as most of the target snapper fishing is undertaken at night. At the same time as this survey was conducted, a separate survey was conducted by VFLOs to assess the catch of pink snapper in Cockburn Sound. Unfortunately, during the spring of 1996, only a small number of pink snapper were caught in the Sound and the estimated catch was less than one ton.
The Fisheries Research and Development Corporation (FRDC) and Cockburn Cement Limited funded a second Cockburn Sound and Owen Anchorage study in 2001/02, focusing primarily on blue swimmer crabs. Since the data was collected in the dark, information on catches of pink snappers was also collected during this study. Members of the Cockburn Sound Line and Pot Managed Fishery catch pink snapper in Cockburn Sound.
Pink snapper is mainly caught with a longline, which is allowed to be used by one angler in the fishery. Historically, most of the commercial fishing of pink snapper in Cockburn Sound has taken place in the spring and early summer, with November being the peak month. The long term average monthly commercial catch of pink snapper in Cockburn Sound is shown below.
ISSUES AND PROPOSALS
- I S A SPAWNING CLOSURE NECESSARY
- B OUNDARIES FOR THE SPAWNING CLOSURE
- S TARTING DATE FOR SPAWNING CLOSURE
- C LOSING DATE FOR A SPAWNING CLOSURE
- T RANSPORTATION AND LANDING OF PINK SNAPPER THROUGH C OCKBURN S OUND
Research on the distribution of pink roe has shown that pink roe spawning occurs in the shallow waters of Warnbro Sound adjacent to Cockburn Sound (Wakefield, unpublished). In relation to the proposal to extend the closure to cover the metropolitan area, a key consideration that needs to be taken into account is the mortality following the release of pink hatches at depths greater than 50 m. Even if the pink fishery were closed, anglers targeting other demersal species would still catch pink.
That the closure limits for the spawning of metropolitan pink tern be defined as those waters of Cockburn Sound and Warnbro Sound (see Figure 5). The extension of the closure until November should be considered as a precautionary measure to reduce fishing mortality on the spawning stock of metropolitan grayling. In order to provide the most effective protection for pink terns spawning in Cockburn Sound, the current closure is based on a ban on the taking, landing and possession of terns.
Some anglers have expressed concern that this closure will effectively prevent them from catching pink snapper outside Cockburn Sound and returning to land their fish on ramps in the closed area. To allow people to land pink snapper in Cockburn Sound, the ban on landing pink snapper during the closed period would have to be lifted, as would the ban on possession - as people would have to transport fish through the closed area to get there. A ban on only catching pink snapper would reduce the closure's effectiveness, as people who may have fished illegally in the Sound could claim that the fish landed were caught outside Cockburn Sound.
Research data on the length frequency of pink snapper in Cockburn Sound and the oceanic fishery has been collected over the past three years as part of a PhD project (Wakefield). This research indicates that approximately 95% of the pink snapper that aggregate in Cockburn Sound are over 70cm in length. Given the large average size of spawning pink snapper in Cockburn Sound, the available data indicate that the majority of these fish can be protected by imposing a maximum size limit of 70 cm during the peak spawning season.
To be effective, it is proposed that the spawning closure apply to the taking of pink snapper as well as banning the possession of pink snapper by persons "actively" fishing in Cockburn Sound during the spawning closure. This would allow people to transport pink snapper under 70cm through the closed area, but they would not be able to stop and fish in Cockburn Sound if they had pink snapper in their possession. Having a maximum size in addition to a spawning closure on the roof of pink snapper in Cockburn and Warnbro Sounds can provide sufficient protection for spawning pink snapper while still allowing people to land pink snapper under 70cm that have come from the sea area outside Cockburn and Warnbro sounds.
From 1 October to 30 November, Cockburn and Warnbro Sounds have a closed season for rosy grouse. During the spawning closure there is a ban on the possession of walleye while fishing in Cockburn Sound.
SUMMARY OF PROPOSED MANAGEMENT ARRANGEMENTS 17
12 Report of the Rock Lobster Industry Advisory Committee to the Honorable Minister of Fisheries 24 September 1987. 94 Report of the Rock Lobster Industry Advisory Committee - Management arrangements for the Western Lobster Fishery for the 1997/98 season. 103 Future management of the water charter industry in Western Australia by the Tourist Fishing Operators Working Group (September 1997).
123 Future Directions for the Rock Lobster Industry Advisory Committee and the Managed Western Lobster Fishery. A discussion paper prepared by Kevin Donohue on behalf of the Rock Lobster Industry Advisory Committee.
