This week it has been brought to my attention that there is a proposal to dredge for scallops inside a ‘Special Area of Conservation’ located in Cardigan Bay, Wales. This proposal has divided opinions. On Twitter this week Professor Callum Roberts, a marine conservation biologist at the University of York (UK) lamented that there was ”No hope for UK marine conservation if this mad proposal to scallop dredge in a protected area goes ahead” . Dr Magnus Johnson, a Crustacean Fisheries and Ecologist researcher at the University of Hull (UK) quickly countered “It is worth reading the science by first!”, following with a couple of hashtags “#eatmorefish #eatmoreshellfish”. Two scientists, with two opposing views… what is going on?
What is a Special Area of Conservation anyway?
These are something unique to the European Union. They arise from the Habitats Directive, first adopted in 1992 in response to a European convention called the Berne Convention. Special Areas of Conservation (SAC) are designed to protect a number of habitats and species (plants and animals) considered endangered, vulnerable, rare, or endemic. Once a SAC has been formally designated, the establishment and implementation of management measures are largely left down to the individual Member State. However, there are certain things that they must do. Briefly, under Article 6 of the Habitats Directive, these include:
Continue reading How special is a ‘Special Area of Conservation?
Our ever-improving technology has allowed us to fish longer, catch more, and move further from land. It has also allowed us to fish deeper. EU statistics indicate that between 1950 and 2006 fishing depths increased from an average depth of 407 metres, to 535 metres.
Life in the deep is slow-paced. Food is scarcer than in the sunlit surface waters. Species grow slower and live longer. Some deep-sea corals, like the one in the image, are thought to be over 4,000 years old. Traits like these are why organisations like Marine Conservation Institute that ” The deep-sea is the world’s worst place to catch fish” . It’s not just the sustainability of targeted species that is causing concern, but of those caught as bycatch, as well as damage to the seabed and the flora and fauna living in and on it – like the coral in the photo. So can deep-sea fishing ever be managed sustainably? A recently published study from Joanne Clarke, a PhD student at the University of Glasgow, and colleagues suggests that there might be a way to make the practice less damaging. Continue reading How deep is too deep for commercial fishing?
Bottom-trawl fisheries may supply us with much of the tasty fish we like to enjoy, but it does come with its problems. Also known as ‘dragging’, bottom trawling essentially involves dragging a large net, held open either with a beam (beam trawling) or large metal/wooden ‘doors’ (otter trawling) along the sea bed, or just above it. It is used to catch a range of commercial species like cod, shrimp, flounder, and halibut. One of the problems of trawling is that it is not a very selective form of fishing. Other species are caught in the process, and this bycatch can include at risk species such as skates, rays and sharks. As well as ecological implications, bycatch can be bad for fishers, who often end up throwing away bycatch either because it isn’t worth anything, or because they are not allowed to land it. Bycatch reduction is a win-win for fishers and for the marine life caught.
Reducing bycatch of sharks, rays, and skates (collectively known as elasmobranchs) in bottom trawls is one of the many fishery-related issues on the mind of scientists at Marine Scotland Science. As this piece of research from the Marine Scotland Science team shows, one possible solution (though not perfect) may not be all that tricky to implement. Continue reading Reducing bycatch of skates and rays – stop tickling them!
Predicting the future is a tricky business. As then United States Secretary of Defence Donald Rumsfeld famously said “There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don’t know. But there are also unknown unknowns. There are things we don’t know we don’t know” . Then there is the interactions between all the variables that determine the outcome of a particular event. However, few things work in isolation and species decline often results from the accumulation of different stressors. If we want to put in place conservation management measures that are effective in the long term, then we need to be able to put our known (and measurable) stressors together and figure out what, cumulatively they mean for our potentially at risk species.
The shy albatross (Thalassarche cauta) is an endemic to Australia, breeding on just three Tasmanian islands, including the aptly named Albatross Island. The albatross of Albatross Island have a long history of human interest. In the early 19th century adult albatross were extensively hunted for their feathers and egg, taking their numbers down from an estimated 11,100 pairs to just 400. The population is now recovering, but still faces a number of possible threats. High on this list are two issues – changing climatic conditions, and the accidental capture of the albatross in longline and trawl fisheries. To understand just what the combined impact of these stressors could mean for this vulnerable bird, Robin Thomson and colleagues from CSIRO Marine and Atmospheric Research, together with the Tasmanian Government Department of Primary Industries, Parks, Water and the Environment (DPIPWE) put together a model that can hopefully direct management to ensure these birds survive in the long term.
Continue reading A brighter future for the shy albatross
I don’t know about you, but I wouldn’t mind being there right now. This is one of the Fijian islands in the Pacific, and the second largest in the group. As serene as the picture is, not all is serene for the Islanders. Fishers in Nagigi, a small community based on the south coast of Vanua Levu Island have been noticing that the number of fish and the size of fish have been decreasing, and habitat degrading – a big problem for a community heavily dependent on its marine resources. This decline isn’t necessarily down to big foreign boats coming in and taking the critters on which they depend. Instead, overexploitation and habitat destruction seems to arise from the ever-increasing number of locally based fishers. The source of this claim? The villagers of Nagigi.
In this paper, Abigail Golden from Columbia University and fellow researchers explore the idea of setting up a short-term no take marine protected area within Nagigi’s coastal tenure area (known aqoliqoli ). This idea hasn’t come from the researchers nor from any top-down government as tends to happen in western countries. Instead the idea has come from the village leaders themselves. This sort of bottom-up governance is far from unheard of. The Pacific Islands are small and numerous, and have a long history of small areas of land and coastal waters managed by local communities. Some have worked well, some have not, and many have come under strain or been lost through both technological developments, increasing population, increasing demands for resources, and cultural change. Still, a well-managed community based MPA can work well, particularly in these remoter locations, and especially were more rigorous research and recording is absent. Regardless of where you are in the world, there are a number of vital steps needed for good management. One involves getting as much information as possible – about the species that are there now, the fishing methods used, an idea of how conditions have changed, and perceptions towards different management methods. The other involves bringing the local community into the conservation planning in a meaningful way. So the team went out and conducted two types of surveys – one looking at the species living on the reef at the time, and one talking to some of the villagers themselves. Continue reading Community-based conservation to rebuild fish stocks
Ocean wildlife spotting tours don’t necessarily run year-round, instead only going out on the water when the primary species of interest is likely to be in the area. You may go out and see so much wildlife you can barely count, or you may go out and return without seeing anything. If you are a fisher, you may have a number of different spots you fish from, or you may use a ‘fish finder’ that points you to where they are most likely to be. If you could see the smaller critters – the zooplankton, the larval stages of larger marine species (including some that eventually become largely sedentary), you would see that they too move. In the ocean, creatures move. Some move short distances, some may cross the global ocean. The ocean itself is highly dynamic – not just over space, but over time. This variability in turn gives rise to variability in primary production – and this means that the preferred habitat and vital food resources also shift in time and space, giving rise to a patchy distribution of mobile species, like pelagic fishes, zooplankton, and sea turtles.
So, we have an ocean that is dynamic in both time and space. We have species that are dynamic in abundance and distribution across time and space. And we have people, using the ocean differently across time and space. Yet we draw lines in the ocean, managing our use of it as if everything fitted into nice neat little boxes. People like lines. Lines denote boundaries, allowing us to categorise and compartmentalise the natural world neatly. We have our Exclusive Economic Zones (EEZs) denoting countries territories. We have marine protected areas that can look after key habitats. But when dealing with the ocean we can see that the world doesn’t necessarily fit into such neat little boxes. Management placed in a fixed area can work really well for some things but when dealing with mobile species – and indeed mobile people, we need something else to enhance static spatial management measures. As outlined in a paper lead by Rebecca Lewison of San Diego State University, a team of researchers from around the globe (including myself) dynamic ocean management could be just what we need.
Continue reading The ocean and its inhabitants aren’t static, so why do we manage them as if they are?
Dealing with overfishing and destructive fishing practices are a huge issue for marine conservation and management. Tackling this problem, and trying to repair some of the damage is no easy task. We know that if they are done properly, no-take marine protected areas can make an impact, not only reducing habitat degradation by removing damaging fishing techniques, but also increasing the density and even the individual size of species targeted by fisheries. The benefits these no-take zones provide can spill over to fishers too. And that’s not just a scientist point of view either – take a look at this short (5 minute video) focusing on lobster potter Geoff Huelin who fishes around Lundy Island – the UK’s first no-take zone.
There are many factors that can make or break a no-take zone. In the video Geoff touches on just one of those factors – policing the zone to make sure that people are abiding by the regulations. This is important. It’s no good having regulations to protect an area from fishing if fishing happens there anyway. It is the action of people – not the designation itself per se, that makes an appreciable difference to marine biodiversity recovery. Geoff tells us that for the Lundy Island no-take zone enforcement isn’t a huge challenge because the no-take zone is viewable from the shore. There is, Geoff tells us, usually somebody watching. But this can’t be said for all no-take zones. It’s not just distance from the shoreline that can impact on enforcement capabilities. Lundy’s no-take is small. Some no-take zones are huge, and very often manager’s budgets and resources are limited. Take the Great Barrier Reef Marine Park for example which suffers hundreds of infringements of its regulations each year. Sure both commercial and recreational fishers who break the regulations inside the Park are successfully caught every year using a host of different surveillance techniques, but many more are likely to go unnoticed. Getting a handle on the scale of non-compliance is the very issue explored in this recent paper by David Williamson from the ARC Centre of Excellence for Coral Reef Studies and fellow researchers. Continue reading Old fishing line hints at fishing levels inside no-take marine protected areas
This not so small ocean critter is an angelshark (Squatina squatina) – also known as a monkfish. Back in the 19th and early 20th century the angelshark had a pretty wide distribution across Europe, and was particularly common around the coasts of the UK, Ireland, and Atlantic Iberia. A nocturnal feeder, these guys bury themselves in sediment and lies in wait for a tasty morsel which, for the angelshark, includes skates, flatfish, and (as once recorded) cormorants. Unfortunately, being a demersal species (living on or near the seabed) they are quite vulnerable to being caught as bycatch in fishing gear like trawls, and bottom lines. Unfortunately for the angelshark, they are also quite a tasty species, so they have also been deliberately targeted by fishers. Slow growing, and producing relatively few offspring, angelshark numbers plummeted, and today it is largely absent from many of the waters it once inhabited. The numbers of angelshark is now so low that the species is listed as critically endangered on the International Union for Conservation of Nature Red List.
There seems to be a somewhat predictable pattern to fisheries exploitation. First, as catches declined and technology improved, we responded by moving further out to sea, into deeper grounds, and targeting new species. Second, we tend to target predators first then, as the catch of those guys decline, move our focus onto different species lower down the food web. The concept of “fishing down marine food webs” was first introduced by Daniel Pauly back in 1998. Daniel used global catch data to infer that a decline in the mean trophic level of the species (an average of how far up the food chain a species is) being caught directly related to what was actually in the oceans. In other words we are catching fewer predators because there are fewer in the oceans. Of course the situation is much more complex than that, and there may be other reasons for changes in trophic catch levels such as regulation changes, as highlighted in a later paper by Trevor A Branch of the University of Washington and a team of collaborators. Whatever the reasons for the declines, Pauly’s findings have been mirrored by many other papers that focus on commercial fishery catches at regional scales. Most recently, Carlotta Molfese and Janson Hall-Spence of Plymouth University, and Doug Beare of WorldFish have cast an eye over commercial fisheries data from the English Channel, and assessed how catches from the area have declined since the early 20th century. Continue reading The changing face of fisheries in the English Channel