Biotoxin Update - 11 November 2019
The IMAS research program investigating the linkage between rate of paralytic shellfish toxins (PST) uptake in rock lobster and the early warning bivalve shellfish has collected two sets of lobster samples from the Mercury Passage area since the last biotoxin update (14 October). These rock lobster samples are showing a decline in the levels of PST, however the PST levels are still above or very close to the maximum limit permitted for human consumption.
Further rock lobster and other species samples will be collected from the Maria Island biotoxin zone and adjacent zones to determine whether these zones can open on the scheduled dates for the rock lobster season in December.
The monitoring of PST levels in bivalve shellfish species as an early warning for the lobster fishery on the East Coast continues under the Rock Lobster Biotoxin Monitoring program. This monitoring program shows that PST levels continue to remain very low in all areas other than Mercury Passage.
Further updates will be provided on this webpage.
Biotoxin Update - 14 October 2019
Paralytic shellfish toxin (PST) levels above the maximum acceptable levels of biotoxins in shellfish for human consumption (the Australia New Zealand Food Standards Code) have been recorded in mussels in Mercury Passage.
The monitoring of PST levels in bivalve shellfish species as an early warning for the lobster fishery on the East Coast will continue under the Rock Lobster Biotoxin Monitoring program. Over winter and spring, the levels detected along the East Coast have been low and the data from areas other than the recent Mercury Passage results, have not been elevated or of concern.
Coincidentally, an IMAS research program investigating the linkage between rate of PST uptake in rock lobster and the early warning bivalve shellfish also sampled lobster from Mercury Passage area on Monday 7 October. These rock lobster samples have returned PST results well above the maximum acceptable levels of biotoxins in shellfish for human consumption.
Further rock lobster and other species samples will be collected from the Maria Island biotoxin zone and adjacent zones to determine whether these zones can open on the scheduled dates for the rock lobster season in December.
Archives - Rock Lobster Fishery Updates June - August 2019
Rock Lobster Fishery Update - 7 August 2019
The area south of a line running due east from Boltons Beach at 42° 24’ 10” S to Marion Bay (boundary line at 42° 49’ 00” S) will re-open for rock lobster fishing from 4pm on 7 August.
The rock lobsters collected by the IMAS dive team earlier in the week as a part of the research project described below have been tested and are clear of paralytic shellfish toxins (PST).
Rock Lobster Fishery Update - 2 August 2019
At 00:01am on Monday, 5 August part of the Maria Island Biotoxin zone will be closed to allow IMAS to collect rock lobster samples for biotoxin testing.
The area to close is south of a line running due east from Boltons Beach at
42° 24’ 10” S to Marion Bay
(boundary line at 42° 49’ 00” S).
Pots must be pulled from this area by midnight on Sunday, 4 August.
Results are expected midday Thursday 8 August. Subject to the results, the area will be reopened immediately. Fishers will be notified by email and SMS. The DPIPWE website will also be updated.
The sampling is part of a significant IMAS Biotoxin research project to answer a critical question relating to how quickly lobsters take up biotoxins once a harmful algal bloom starts.
Rock Lobster Fishery Update - 4 July 2019
The area south of a line running due east from Boltons Beach at 42° 24’ 10” S to Marion Bay (boundary line at 42° 49’ 00” S) re-opened for rock lobster fishing from 4pm on 3 July.
The rock lobsters collected by the IMAS dive team earlier in the week as a part of the research project described below have been tested and are clear of paralytic shellfish toxins (PST).
Rock Lobster Fishery Update - 28 June 2019
Closure of part of the Maria Island Biotoxin Zone for IMAS Research
At 00:01am on Monday 1 July part of the Maria Island Biotoxin Zone will be closed to commercial fishing to allow IMAS to
collect rock lobster samples for biotoxin testing.
The area to close is south of a line running due east from Boltons Beach at 42° 24’ 10” S to Marion Bay (boundary line at 42° 49’ 00” S).
Pots must be pulled from this area by midnight on Sunday, 30 June.
Results are expected by midday Thursday 4, July. Subject to the results, the area will be reopened immediately. Fishers will be notified by email and SMS. The DPIPWE website will also be updated.
The sampling is part of an IMAS Biotoxin research project.
Indicative map illustrating the new boundary line near Boltons Beach/Little Swanport
Rock Lobster Fishery Update - 13 June 2019
The area south of a line running due east from Boltons Beach at 42° 24’ 10” S to Marion Bay (boundary line at 42° 49’ 00” S) will re-open for rock lobster fishing from 3pm on 13 June.
The rock lobsters collected by the IMAS dive team earlier in the week as a part of the research project described below have been tested and are clear of paralytic shellfish toxins (PST).
Rock Lobster Fishery Update - 7 June 2019
Closure of part of the Maria Island Biotoxin Zone for IMAS Research
At 00:01am on Tuesday 11 June, part of the Maria Island Biotoxin Zone will be closed to commercial fishing to allow IMAS to
collect rock lobster samples for biotoxin testing.
The area to close is south of a line running due east from Boltons Beach at 42° 24’ 10” S to Marion Bay (boundary line at 42° 49’ 00” S).
Pots must be pulled from this area by midnight on Monday, 10 June.
Results are expected by midday Thursday 13 June. Subject to the results, the area will be reopened immediately. Fishers will be notified by email and SMS. The DPIPWE website will also be updated.
The sampling is part of an IMAS Biotoxin research project.
Indicative map illustrating the new boundary line near Boltons Beach/Little Swanport at the north of the zone
Background Information
Under the current rock lobster biotoxin monitoring plan, paralytic shellfish toxin (PST) levels in mussels are used as an early warning alarm to decide when to close a zone to sample rock lobster. Previous tank studies suggest there could be a 14 day lag period between high PST levels in mussels and high PST levels in lobsters. A more recent study indicates that if the lobster is eating prey items with very high PST levels, the resulting lobster PST levels could reach 0.8mg/kg within a much shorter timeframe.
To answer this is a critical management question, the IMAS project team is proposing to track PST uptake in lobsters before, during and after a bloom.
The research project will collect 5 lobsters from the southern half of the Maria Island Zone (Maria Island revised zone) once a month in June, July, and August. If a harmful algal bloom (HAB) event occurs, the sampling may increase to fortnightly and continue during the closed season, reverting back to monthly when the bloom declines.
The zone will be closed to commercial lobster fishing for sampling and will reopen as soon as the results are available. It is anticipated that the closure will be 3 – 4 days for each sampling round. The lobster samples will be analysed by the AST Labs in Hobart. If the preliminary screen results are below 0.4 mg/kg, the zone will be reopened immediately, otherwise the confirmatory results will be used to determine the status of the zone in line with the Biotoxin decision protocols.
The rock lobster biotoxin monitoring program and response plan will continue to operate as normal and independently of the project sampling.
If you require any further information on the closure please email Hilary Revill at
hilary.revill@dpipwe.tas.gov.auFor further information on the research project
FRDC 2017-086 Improved risk management of paralytic shellfish toxins in Southern Rock Lobster go to the
IMAS website.
Indicative map illustrating the proposed trial division of the Maria Island Biotoxin Zone
Biotoxin Zones and Boundary Maps
Biotoxin Decision Making Protocols
DPIPWE Wild Fisheries has developed the
Rock Lobster Biotoxin Plan and Decision Protocol in consultation with the Tasmanian Rock Lobster Fisherman's Association, the Commonwealth Department of Agriculture and other stakeholders. It is used to determine management responses in relation to a Paralytic Shellfish Toxin (PST) event. The policy for the
Recreational Rock Lobster Fishery for Biotoxin Events is also below.
Rock Lobster Biotoxin Monitoring Program and Decision Protocols 2018
(718Kb)
Recreational Licence Refunds
Please note that recreational licence refunds
will not be granted if you are unable to fish in some waters due to biotoxin closures. Licences grant access to all Tasmanian waters and biotoxin closures apply only to specific zones within those waters. Licence holders can still fish outside any closed areas.