Major issues still not addressed and a major fishery and Tasmania's marine environment remain at risk
The rock lobster fishery is currently in crisis. Despite having an excellent management framework and relatively well-resourced research and management support, major problems have been ignored for too long. Excessive commercial inshore fishing pressure, localised overfishing, habitat change associated with knife-edge fishing (what is this) and consequent expanding urchin populations are all issues that have been recognised for years, but have not yet been addressed by any meaningful changes to management. Since 2006, poor recruitment has added to these already serious problems. Habitat change due to the rock lobster fishing and overfishing are now major concerns, particularly in the east and southeast regions, that can no longer be ignored.
The government is currently undertaking a review of the management of this fishery to fulfil a statutory requirement under the Living Marine Sources Act, 1995. While the review recognises most of the major problems associated with this fishery and makes some useful suggestions, it is unlikely that the management changes so far suggested in the Discussion Paper will actually solve these problems.
Much has been made of the cut to the total allowable catch (TAC) for the commercial fishery. This season there has been a 10% reduction, which will be followed by a 5% cut in each of the next two seasons. Last season, the fishery could not manage to reach the TAC. The reduced catch for this season combined with the permitted carry-over of uncaught fish from the last season means that more fish can be taken out of the water this season than were actually caught in the last one.
It is generally accepted that a TAC that cannot be caught is not only a meaningless management tool, it is an indication of a fishery in trouble.
While modelling suggests that the 10%+5%+5% cut in TAC will be useful, the modelling is based on the assumption that future recruitment will be similar to that experienced over the last 10 years. This is probably over-optimistic, given that the current biomass is now greatly reduced and presumably producing fewer eggs. Unless recruitment greatly improves, a larger cut in the commercial TAC will be required and must be considered.
Considerable uncertainty surrounds the actual recreational catch and a more rigorous method for measuring it needs to be implemented. The most effective would be to issue a set number of tags with each recreational fishing licence. An option to allow fishers access to additional tags could be considered. The cost of this system should be borne by the users. Given fishers’ outlay on travel and equipment, the small additional cost of tags and associated administration would be insignificant. Tags would provide much better information on recreational fishing pressure and could also be used as a management tool to direct effort away from overfished areas. They would also assist with compliance and enforcement. The review's Discussion Paper does not consider the use of tags in the recreational fishery, even though there appears to be reasonable support for this idea among fishers.
The Discussion Paper also fails to identify the growing number of once-productive areas that are now all but completely fished out. (suggest delection)It is common knowledge that many areas that used to be accessible and popular locations for recreational fishers no longer provide access to rock lobster. Fortescue Bay, Spring Beach and Bicheno are examples of this kind of degradation. Overfished areas are of no use to either the recreational or commercial fishery in their current state and should be rehabilitated. It is surprising that this problem is not even identified in the Discussion Paper, however it is a problem that needs to be addressed if biodiversity values are to be protected, habitat change is to be halted and recreational fishing values are to be maintained. The easiest way to do this is to temporarily close these areas to fishing until stocks recover. Once recovery has occurred, access should be limited to recreational fishers and both annual and daily bag limits should be imposed, using tags, so that rock lobster populations are maintained at acceptable levels.
More than 15 years have passed since the TCT raised concerns about the growing Centrostephanus urchin barrens and brought this issue to the attention of the Tasmanian Government, but there has still not been a single management decision directed at solving this problem. Finally in this review, the Discussion Paper identifies the relationship between increasing numbers of Centrostephanus urchins and spreading urchin barrens, and the absence of their main predator, large rock lobster. It suggests a maximum size limit of 138mm should be introduced. This is a useful management tool, as it protects rock lobsters that are large enough to prey on Centrostephanus as well as mature female rock lobsters that produce lots of eggs. But the Discussion Paper suggests that this size limit should only be applied to a relatively small section of coast. (suggest deletion) To have the best effect, it should be applied to all inshore waters shallower than 30m from north of Eddystone Point to South East Cape at least. A better option would be to apply the limit to all Tasmanian waters and to both commercial and recreational fishers. This would make compliance and education easier, and help stop the spread of urchin barrens into new areas.
Unfortunately, it is too late for a maximum size limit alone to solve the problem. Rock lobster populations simply will not increase fast enough to control urchin numbers within a useful timeframe, if at all. At the current level of fishing it is clear that few animals reach the maximum size limit in the critical areas in the east and southeast regions. Even with the proposed catch reductions, there is no evidence presented in the Discussion Paper that would suggest that the size limit alone would protect enough rock lobster to make any difference. Some scientists suggest that it would take 18 to 50 years for populations to rebuild to the level necessary to control the urchins. The TCT suggests that much more needs to be done if there is to be any meaningful effect on urchin numbers and urchin barrens. Translocation of larger rock lobster may be an option. Culling urchins should also be considered at least until rock lobster numbers recover. But perhaps the most cost-effective mechanism would be to close areas at risk from urchin barren to all forms of fishing until the population density of large rock lobster increases to the point where urchin numbers and barrens can be controlled.
(suggest deletion) Urchin barrens formed by Centrostephanus urchins should be given the highest priority. All evidence suggests that knife-edge fishing and overfishing by the rock lobster fishery is the primary cause of habitat change through the creation of Centrostephanus barrens. This means that current management is not working and that the fishery is unsustainable in many areas and threatens ecological processes. It is the view of the TCT that this places the commercial fishery at risk of losing its export accreditation under the EPBC Act.
A major difficulty associated with managing this fishery is identifying the variables that determine the rock lobster population and habitat change, and separating effects of climate change, fishing effort and management changes.
No-take marine protected areas (MPAs) offer the best way to differentiate between the impacts of these and are vital for assessing the impacts of fishing itself. The Tasmanian Marine Protected Area Strategy provides a process that can create a system of representative MPAs throughout Tasmania’s marine bioregions, which would enable a much better assessment of the effects of this fishery as well as the variations due to climate change or other environmental factors. (suggest deletion)Again, the Discussion Paper does not mention the need for reference areas that are necessary to assess the effectiveness of management decisions, fishing impacts and climate change.
While it is usually impossible to make a direct link between egg production and recruitment success in species such as rock lobster, it certainly would not hurt to ensure that a significant proportion of reproductive animals is fully protected from fishing activity. This is, after all, one justification for having a size limit that allows a large part of the population to reproduce. The TCT suggests that more should be done to protect brood stock in MPAs. It is clear that MPAs allow rock lobster to grow to a large size and that large individual female rock lobster are particularly good egg producers. A series of no-take MPAs in each of Tasmania's marine bioregions should be of some benefit to egg production. However, much remains unknown about the factors associated with recruitment success such as the ideal circumstances for egg production in terms of location and (?)timing. Having a series of protected areas across all of Tasmania's marine bioregions could increase the probability that fertile eggs would survive and mature through to settlement.
Excessive inshore fishing pressure from both commercial and recreational fishers continues to be a problem. This is due to considerations of accessibility in the case of recreational fishers, and market forces and economics for commercial fishers. To address this problem, limitations on catch/possession limits need to be considered . The Discussion Paper’s suggested reductions in bag and position limits for recreational fishers do not go far enough to protect overfished areas along the east and southeast coastlines.
The TCT suggests that the overriding principle guiding bag limits for recreational fishers should be to provide enough fish for a meal. (suggest deletion) A daily bag limit of two rock lobster and a possession limit of four would seem to be more appropriate. Possession limits for fishers should be reduced to two, with a house limit of four, without a sales tax invoice, and no possession by individuals less than 10 years of age as suggested in the Discussion Paper. In more heavily targeted areas, a further reduction would be appropriate.
But reduction in the recreational bag limit alone will not ensure that any fish left in the water will not be taken by the commercial fishery, or that recreational fishers will not compensate by making more fishing trips.
(suggest deletion)Variations in growth rates, size at maturity and fishing pressure means that standardising fishery management procedures across the State is inappropriate. Area-based management that is sensitive to biological factors and fishing pressure is needed. Bag limits, possession limits and size limits should be determined on a region-by-region basis, and access to these areas by both commercial and recreational fishers managed accordingly.
Currently, the management of the Tasmanian rock lobster fishery does not appear to comply with the objectives of the Living Marine Resources Management Act, 1995, which, amongst other things, aims to ‘achieve sustainable development of living marine resources having regard to (This is ungrammatical but is it an accurate auote
- increase the community’s understanding of the integrity of the ecosystem
upon which fisheries depend; and
- provide and maintain sustainability of living marine resources; and
- take account of the community’s needs in respect of living marine resources;
- take account of the community’s interests in living marine resources.’
The management of the current fishery does not appear to comply with this Act.
The future of the Tasmanian rock lobster fishery depends on the outcome of this review. Habitat change as a result of this fishery threatens the environmental foundations upon which this fishery is based. It is likely that difficult and unpopular decisions will have to be made to solve the problems created largely by the recreational and commercial fisheries. Climate change and recruitment failure make the situation even more difficult. The choice, however, is clear: either the problems are dealt with now, or there will be continued decline in the recreational and commercial fisheries, and increasing habitat degradation that undermines the local marine ecosystem and other fisheries, as well as the rock lobster fishery itself and the ruin of the shallow rocky reef ecosystem along much of Tasmania's coastline.
Tasmanian Conservation Trust