Rock lobster industry commentator Daryl Sykes provides the third of a series of articles exploring initiatives from the industry
In two previous articles we explored key developments in the contemporary history of the New Zealand rock lobster fisheries and the industries’ active role in these initiatives. This time, we focus on more winners, beginning with an ambitious collaboration led by the NZ Rock Lobster Industry Council (NZ RLIC), alongside Victoria University of Wellington and Seafood Innovations Ltd.
Population Dynamics
Rock lobster fisheries for Jasus Edwardsii are managed as nine separate stock units and for each of these there is an annual review of total allowable catches and total allowable commercial catches, informed by stock assessments. Stock assessments are done using complex mathematical models, which require accurate catch and effort data, size and sex distribution data and some underlying assumptions about the productivity and behaviour of lobster populations.
The broad aim of the industry-initiated and part-funded DNA sequencing project was to use state-of the-art DNA markers (Single Nucleotide Polymorphisms, SNPs) to provide information on larval exchange patterns (connectivity) for New Zealand rock lobsters. The results allow the development of enhanced management strategies, new marketing, wild fishery enhancement and forensic opportunities over the next decade.
This was the first species DNA profile completed in New Zealand and the first for a lobster species internationally. The project findings confirmed that New Zealand’s rock lobster population functions as a single, well-mixed species, with genetic data showing consistent gene flow across regions. This evidence suggests that recruitment in any given location likely originates from a broad and interconnected larval dispersal area.
There are, however, some environmentally influenced genetic traits that vary by location. Previous research suggests that these differences may represent evolutionary adaptations specific to local environments, which likely explains these subtle spatial genetic differences observed in the rock lobster DNA profile. Despite these localized variations, the findings support the continued use of the nine-stock management approach, as the overall genetic connectivity across regions ensures effective management at this broader spatial scale.
Demonstrating the value of rock lobster fisheries helps managers assess the costs and benefits of management decisions. The industry aims to maximize economic returns by maintaining stock sizes above statutory levels and keeping catches within set Total Allowable Catch (TAC) limits.
Environment and Conservation
Mindful of their environmental responsibilities and building on a local initiative by the CRA5 Rock Lobster Industry Association (CRAMAC 5) the NZ RLIC actively promotes a Whale_Safe programme (https://nzrocklobster.co.nz/documents/whalesafe/) to assist pot and trap fishermen in avoiding and/or mitigating the risk of entanglements.
Whale_Safe is a booklet offering detailed insights into cetacean movements and behaviour, species identification through photos and illustrations, and gear-setting advice to prevent entanglements. The content was commissioned from Dr. Martin Cawthorn, a globally recognized expert in cetacean biology and behaviour.
Constraining Illegal Catches and Black-market Sales
The quantities of rock lobsters illegally sold in New Zealand is currently suspected to be at high levels. In a move to stop this, Licensed Fish Receivers (LFRs) in the Auckland area are ‘horn tagging’ all packhorse lobsters that go through their premises for local sale. A white, numbered, security tag is attached to an antenna of each lobster. Each LFR maintains a register of the date and the tag numbers that have been sent to each of their customers, and these tag numbers will be included on every invoice. The tags are food safe. The tag, its inscription, and number should not and cannot be removed. The horn tagging programme lets Auckland consumers know that their product has come from a legitimate source and will allow easy identification for Fishery Officers.
A similar programme was first trialled for the Kaikoura restaurant and hospitality trade in a voluntary initiative by CRAMAC 5 supported by the regional Ministry Compliance team.
Food Safety and Consumer Confidence
Recognizing the reputational importance of meeting food safety and hygiene standards for rock lobsters, the NZ RLIC recently reviewed its national Biotoxin Risk Management Plan. Marine Biotoxins have been an issue in New Zealand since 1993. When a toxic algal bloom occurs, shellfish accumulate the toxins after feeding on the algae. Rock lobsters can then accumulate the toxins in their digestive system as they feed on the toxic shellfish. There is no evidence that toxins accumulate in the muscle tissue that is eaten by consumers, however, many consumers also relish the head meat and gut contents of lobsters (also known as ‘the sauce’). This ‘sauce’ can be potentially very dangerous if toxin accumulation is high.
The NZ RLIC developed a plan to respond to events when there is a risk to rock lobsters. This plan has been endorsed by MPI as the accepted way of managing the risk to food safety and to protect rock lobster export markets.
Animal Welfare
A feature of rock lobster fishing using traps and/or pots is the capture of male and female lobsters of various sizes, and at times, of female lobsters carrying external eggs. Those animals, and all under-sized rock lobsters must be immediately returned to the sea, preferably on suitable habitat. Handling damage to those lobsters, or predation on those discarded, can have consequences for future abundance and availability. The rock lobster industry has undertaken several important initiatives to minimise both.
Ensuring effective escape gaps in pots was an industry driven process that has demonstrably reduced the numbers of undersized lobster hauled to the surface. Harvest and handling protocols, intended to produce the highest quality live lobsters for domestic and export markets, are constantly under review. Industry has made significant investments in post-harvest research throughout the auspices of the CRA8 (Southland) rock lobster industry.
Two phases of research into harvest handling and transport techniques confirmed operational adjustments that have significantly improved the quality of lobsters landed to LFRs, and further reduced discard damage and/or losses. The successful techniques developed in CRA8 have since been progressively adopted as a standard across the industry.
