The Caribbean Sustainable Fisheries Story

The basic concept behind Caribbean Sustainable Fisheries of sustainably producing lobsters was first researched in 1997 involving the World Fish Center.

We are a research and development spin off from a World Fish Center project focusing on the relationship between post larval fish supply to areas and the implications for creating marine reserves.

Those working on the project soon realized we should be looking at fisheries in an entirely different way. We were recording large settlement pulses of post larval fish with a corresponding pulse in numbers of juvenile fish several orders of magnitude smaller. Others in the research community had already demonstrated similar relationships and concurrently several groups published work that really drove the message home.

From the post larval phase in a fishes’ life to the early juvenile phase is an extremely dangerous period. Their chances of surviving this short transition from a deep water planktonic life, to a shallow water nursery existence, can be as low as 1 in 100. The corresponding survival expectancy to minimum breeding age is probably more like 1 in 1000 for many species of reef fish.

These odds really ought to make us question the wisdom of targeting adult fish as the resource! We realized fishers had been fishing the thin end of the wedge since fishing first began; gradually destroying the reproductive capacity of populations and depleting the resource. This historic perspective may sound a little dramatic, until one considers a neat bit of research by Jeremy Jackson which discusses the strong possibility that several species of large fish were driven to extinction in the Caribbean, long before the arrival of Columbus and the ravaging European hordes.

The situation today is becoming increasingly desperate. Expanding populations with increasingly sophisticated life styles and correspondingly efficient technology are rapidly stripping the coral reefs of their commercial fishes. The effects of this problem are now compounded by global warming, with alarming coral bleaching events. At the same time the expansion of tourism continues to exert mounting pressure on fish stocks.

Top of the list for fresh seafood products is the Caribbean Spiny Lobster.

As part of our early studies we were harvesting fish washed over a reef crest at night. Our small crest nets were catching considerable numbers of lobster post larvae and when we extrapolated this catch to the length of the reef we realised that several thousand lobster post larvae were washing over the reef each night. We quickly realised that this represented a resource which could be harvested in commercial numbers.

After several more years of research we had a very good idea what other people had already tried, and a basic model of how much it would cost to grow-out the tiny post larvae lobsters until they were market size. The basic harvest techniques and technology were also approaching something that could be used commercially. Other researchers had already spent many years examining the ecological impact of a post larval fishing strategy for spiny lobsters. Their findings showed that a careful approach to harvest could result in commercially significant numbers of post larvae, with negligible effects on the wild population in consecutive years. This is because the effects of removing the post larvae are diluted by the natural mortality during settlement.

Australian researchers, who arguably lead the world in sustainable fishing, calculated that their lobster fishery could be doubled by creating a post larval harvest fishery alongside their existing lobster fishery (the largest in the world and growing, thanks to careful management).

According to various survival studies carried out on the Caribbean spiny lobster, roughly one post larvae in 1000 will survive until it is breeding age. Thus, theoretically, we can harvest many hundreds of post larvae for every adult lobster caught - but without significantly affecting the wild population. The reality is likely to be much more complex than this and an impossible number of variables would have to be modeled to have 100% accuracy, but this approach is vastly less intrusive to the wild population than removal of the few surviving adults. This becomes more evident when we consider the relationship between the number of eggs/sperm produced, and the competency of those gametes, in relation to the size of lobster. Larger (older) lobsters produce many more eggs each year and the competence of those eggs is likely to be much greater. This knocks on to producing larvae that are much stronger and more likely to survive...etc.

Almost all fisheries are regulated by catch size limits, which are set in an attempt to ensure that each animal, surviving to adult, is at least given the chance to breed once before being caught. This approach is increasingly criticized because of its inadequacy and there is a real danger that the whole fishery begins to drive a natural selection for lobsters to become smaller. Research into other fisheries has shown that this can happen in a relatively short space of time.

Once we were satisfied that we could create a lucrative and environmentally sound alternative fishery, the next big question was how to fit this idea into a business model whilst maintaining a socially responsible framework for growth. When we talk about a fishery, it is sometimes easy to forget that the one thing as important as the fish is the people who rely on them for their livelihood and food. It does not matter how fantastic any new concept is; it will fall flat on its face without the participation and backing of those people who have traditionally used this resource.

It has taken us nearly two years of careful evolution of the rough concept, into a viable package that should provide numerous business opportunities to fishers and young entrepreneurs throughout the Caribbean. The whole enterprise will take the form of a small scale modular system and a series of GPS defined fishery concessions that can be licensed to a wide group of participants in any coastal community. The licensing process will ensure that a sustainable code of practice can be maintained, whilst also providing controls on local market forces and a vital 'fair trade' farm gate price for the produce.

Our approach will be reliant on natural sources of feed. Some of this feed, particularly in the early development of this industry, will come from local supplies of bait fish that are not heavily utilized at present. However, careful calculations have indicated that with a little development, we can grow the most appropriate feeds in deep water, by providing artificial habitat for the post larvae of numerous other species. Most of these species are habitat limited and so their numbers are only kept in check by the fact that there is not enough settlement substrate; thus causing them to settle on artificial substrate will not significantly affect their supply to nearby natural settlement surfaces. Essentially the same concept is applied to the feed, as is used in the harvest of lobsters. The Australians call it Biological Neutrality.

In growing our own feed in this way we may also inadvertently create sufficient late larval stage feed to enhance survival of many species of reef fish. Everything we grow as feed, will produce millions of gametes that are an ideal food source for various different stages of reef fish larvae. Enhanced survival, means larger numbers of settling fish and eventually this may help rebuild fish stocks on coral reefs (incidentally the same gametes are also ideal food for corals that are struggling to survive the adverse effects of global warming. A recent global discussion among coral reef scientists centered on whether we can feed corals to stop them from dying in bleaching events). As with feed, we have designed the culture system to be as biologically neutral as possible, using secondary species and various biological filtration stages to make sure that water leaving the modules is of better quality than water coming into the system.

There is much work to do and our systems are still a way off full commercial viability, however, we are excited by the robustness of our background research and the potential to create a truly eco-friendly money making enterprise.