Introducing 'Finding Larry' - the lobster research project we all need!

What is ‘Finding Larry’?

The National Lobster Hatchery (NLH) enjoys widespread support among fishers and conservationists for our efforts to sustain stocks of lobsters, a keystone of both marine ecology and coastal economies. Fishers who collaborate with the NLH frequently report a surge in the number of sub-adults caught and returned in the years following releases. However, with no suitable method of physically tagging our tiny lobsters before their release so they can be easily recognised and discerned from natural stock upon recapture, the hatchery has never been able to properly quantify the impact of releases. To this end, the NLH has planned an ambitious, multi-phased research project under the working title of ‘Finding Larry’. The proposed research encompasses a suite of interconnected studies that will produce the most rigorous assessment ever undertaken as to the fate of hatchery-reared lobsters following their release into the wild. The findings of this project will be crucial to provide steer and direction on the success of the NLH’s founding activity: the release of juvenile European lobsters to provide additional recruitment, safeguarded breeding stock, and increased sustainability for our traditional, low-impact inshore potting fishery.

Why do we need to re-evaluate the effectiveness of hatchery stocking?

Since the last wave of monitored lobster stocking ceased two decades ago, new rearing techniques and monitoring methods have become established. The few studies that exist on the survival and fitness of cultured lobsters in the wild already provide some of the most encouraging assessments of aquaculture-based enhancement in any stocked species. However, the limitations of physical tagging technology for small-bodied, moulting crustaceans have significantly hindered the regularity and rigour of assessments aimed at estimating the overall impacts and effectiveness of stocking operations. Although proof of principal that lobster stocking fulfils its objectives has been demonstrated, a number of key questions about the practice remain unanswered. Understanding where, when and how hatchery stocking works would be a significant milestone in it becoming one of the established options available to fisheries managers and fisher co-operatives to safeguard the sustainability of lobster fishery harvests.

Why do hatcheries need to assess impact, and who would that benefit?

Quantifiable evidence of the effects of releasing cultured lobsters will provide critical evidence on which hatcheries can ensure continued support from industry and attract the funding required to develop. All hatchery stocking aims to increase the abundance of the target population, yet even where this occurs, improperly managed operations can cause unintended damage to the resilience of the wild stock (i.e. via bottlenecking the population’s genetic diversity or introducing genes maladapted to the environment). This research will provide hatcheries with the knowledge of how best to conduct and adapt their rear-and-release operations, as well as identify whether any negative impacts require mitigation. The resources to undertake impact assessment, and the findings generated by the NLH by this project, would become available to the growing number of organisations operating hatchery enhancement of lobsters. Ultimately, our lobster stocks and the industries they support would benefit from more and better hatchery releases.

How will the project engage the fishing industry and other stakeholders?

To ensure the project is affordable, deliverable and that its findings engage interested parties from industrial and recreational sectors, we will utilise the skills and expertise of existing inshore stakeholders to provide the bulk of the project’s data collection. The project will accomplish this by developing survey techniques which are compatible with the regular routines of commercial trap fishers and volunteer dive surveyors. Fishers will record the number and sizes of the lobsters they catch to define the stock’s abundance and size distribution, and trained volunteer divers will be enlisted to record key indicator species and assess seabed habitats. Areas into which hatchery lobsters are released and comparable control zones will be surveyed in this way, both before and after juveniles are introduced, so that the effect of releases can be quantified and discriminated from natural fluctuations in the population using an established scientific assessment method (the Before-After-Control-Impact approach, or BACI for short). As well as delivering fundamental stock data, fishers will provide land- and sea-based opportunities for researchers to collect tissue samples of their catch for genetic analysis to provide unambiguous identification of which wild lobsters are hatchery-reared.

What new techniques are there and how would they help?

To date, when attempting to assess the impact and success of lobster stocking, a reliance on inappropriate tags has led to release and monitoring protocols being of compromised design. The development of a targeted set of genetic markers to resolve parentage in lobsters promises a leap forward to provide a molecular method by which hatchery lobsters could be distinguished from natural stock regardless of their life-stage or body-size at release. This approach is called parentage-based tagging (PBT), and has led to major breakthroughs in hatchery stocking schemes for many finfish species. From tiny, sub-lethal tissue clips taken from lobsters found in release zones, it becomes possible to genetically assign recaptured released animals to hatchery broodstock, and differentiate between hatchery individuals and natural wild lobsters, even when they look and behave identically and neither is physically tagged. This newly-developed, high-resolution genetic resource provides the opportunity to undertake studies of rearing and releasing strategies to test what works best, including strategies which should be the most successful but which have remained impossible to assess until now. PBT is the first suitable means of identifying lobsters from the point they first transcend from planktonic drifting larvae, and a free-for-all food for fish, to become benthic burrowers able to settle onto the seabed so as to avoid predation. PBT also offers the significant benefit that, via the archiving of their broodstock tissues, hatcheries can commence stocking appraisals opportunistically (i.e. as soon as funding or collaboration were secured) rather than having to embark on tagging-based release research that yields no data for several years, and no definitive results for around a decade.

When and where would this all be happening?

Starting in 2019 and spanning a four-year timeframe, we plan to carry out this project in two southwest locations; the Isles of Scilly and another area in mainland Cornwall (most likely Mounts Bay, Falmouth Bay, or Padstow Bay). Cornwall and Scilly are important hotspots for lobster, supplying ~5% of global landings of European lobster, and the fishery is of vital importance to the rural coastal economies of the region, being the highest value species targeted by hundreds of inshore day-boat fishers who specialise in traditional low-impact methods using static gear. The Hatchery has built up collaborative relationships with a number of marine stakeholders in these areas to facilitate the delivery of the project, and local habitats can support a great abundance of juvenile lobsters, as well as offering the protection of designated Marine Conservation Zones, where artisanal fisheries are able to operate in the absence of more environmentally damaging practices. The geographic isolation of Cornwall, and in particular the Isles of Scilly, is also well suited to ensuring strong buy-in from local stakeholder groups and high sampling coverage to maximise recovery rates among released animals.

Above: The Finding Larry project has several components which all link to provide a holistic and stakeholder-driven approach to monitoring the impacts and conservation benefits of releasing hatchery lobsters to sustain wild fisheries. The funding of a P.I. to start in 2019 is essential to enable the projects to be fully planned, funded and delivered on schedule.

Why now?

Lobster populations are under greater fishing pressure than ever before, leading to a surge in interest in novel methods to sustain stocks. This has led to a growth in the number of new and proposed lobster hatcheries, all of whom would benefit from the improved understanding of the impact of their releases that this project would generate. Among these organisations, the NLH are leaders in providing scientific research as well as lobster releases and sustainability education. It is now well placed to build on this status by expanding the size and scope of its operations. However, any expansion of releases should be built on and driven by improved knowledge of the effect these have on enhanced stocks. The development of PBT tools now enables the identification of hatchery releases among the wild stocks without using restrictive physical tags, and the vast potential of novel sea-based rearing systems to stimulate improved post-release survival among ecologically conditioned juveniles can now be assessed for the first time. Our ongoing Lobster Grower 2 project has reared thousands of animals in this way since 2016, many of which will be 3 years old (halfway to the age they typically recruit into the fishery) when the project closes in 2019. The unique availability of these sub-adult lobsters makes it possible to release two different age groups and monitor survival between them—from juvenile to sub-adult, and sub-adult to adult—in order to quantify fishery impacts in half the time usually needed.

What other partners would this research require?

This project would need a collaborative partnership to succeed, and provisional agreements on this front have already been reached with a range of important organisations. Co-operative groups of lobster fishers in Cornwall and Scilly have provisionally committed their involvement to host researchers and organise access to sample their catch. Cornwall and Isles of Scilly Inshore Fisheries and Conservation Authorities will provide additional support and co-ordination with the fishing industry. Expertise in quantitative ecology and genetic analysis facilities would be required from professional academics of the nearby Universities of Exeter and Plymouth. FoAM, a Penryn-based non-profit organisation who specialise in creating technology which integrates everyday citizens with research science, have agreed to develop a web-linked app that allows researchers and fishers to collect survey data from commercial fishing activities. Other organisations have expressed strong support for the project, including the Marine Conservation Society, Cornwall and Scilly Wildlife Trusts, and the Shellfisherman’s Association of Great Britain. Outside of the core remit of the project, there is also vast opportunity for bolt-on studies, including through academic collaborations, associated PhDs and other linked studentships, which could boost the profile, scope and impact of this research.

What can I do to help?

This project requires us to engage completely with people in the lobster fishing and wholesale industries in Scilly and West Cornwall. Fortunately, we have developed several working relationships with people in these areas, and are lucky enough to have enthused them as to the value of this project. But all research requires money and manpower, and we need both to get 'Larry' off the ground, so if you are a budding researcher or conservationist and want to get involved, or are or know of someone who may be able to provide funding or grant awards to facilitate this research, then please get in touch with Dr Charlie Ellis via email on charlie.ellis@nationallobsterhatchery.co.uk or by telephone on 07940 316348 .