This little critter is a limpet. From the photo they may not look like the most exciting of creatures. If you’ve ever been down to the coast and taken a look at them yourself… your opinion may not have changed. They don’t seem to move around a lot, or do a lot. Of course looks can be deceiving. Under that shell is the limpet’s squishy body – and their big, muscular foot which, alongside a pretty amazing adhesive secretion, they use to cling onto rocks and other hard surfaces. Anyone who has ever had a go at trying to get a limpet off a rock knows how good a grip they can have. This fabulous foot isn’t just used to stop them from drying out when the tide leaves them exposed to the air, or keep pesky predators (or nosy humans) at bay. Limpets are grazers, feeding on tiny algae on the surface of rocks with their raspy “tongue” (called a radula). See that empty space behind the limpet in the photo? That’s where it’s been grazing. Once they have grazed an area they need to find more food. That foot gets to work, and along moves the limpet, munching up all the algae in its path. Some limpet species even appear to have a home – a particular crevice that they return to just before the tide will expose them to the air.
But this isn’t a post about how amazing limpets are. This is a post about animal movements in the ocean.. Or at least 3 different types of animal movement. Some of them move a lot further than you think. Yes, even limpets.
Continue reading Just keep swimming
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?
This is a big post. It’s about big things. Important things too. It deals with Canada – a big country. Actually by area, it is the second largest country in the world. It also has a lot of ocean under its jurisdiction. Take a look at the website of Fisheries and Oceans Canada, a Federal government body, and you will see statements like this:
“The Government of Canada is working to ensure the future health of Canada’s oceans and ocean resources by increasing understanding and protection of our oceans; supporting sustainable economic opportunities; and demonstrating international leadership in oceans management”
Sounds good doesn’t it. The Canadian Federal Government (which has just changed as of yesterday – see bottom of the post) have a several Acts in place to govern the bit of the ocean they have claimed as theirs. Great stuff! Except maybe, as demonstrated in a recently published paper, authored by 19 Canadian scientists including lead-author Megan Bailey (Dalhousie University), “over the past decade decision-making at the federal level appears to have undermined the government’s own mandates for the sustainable management of Canada’s oceans” Continue reading Oh Canada – what about your ocean?
Marine protected areas (MPAs) are pretty nifty tools for marine conservation. You take an area, you give it a designations and (hopefully… but the reality can be quite different) you attach some regulations/legislation to remove harmful activities to whatever it is you are trying to protect inside the MPA and make efforts to rebuild and conserve this spot. The situation of picking an area to designate can become trickier when dealing with ocean wanderers – species that move around a lot, and over great distances. It is safe to say that it is politically unfeasible to designate one area big enough to encompass, for example the movement of sea turtles. Instead, sea turtles may find critical habitat – feeding areas or nesting beaches for instance, covered by an MPA. We can’t protect them everywhere, but we can build a case to protect them where we know they hang out in large numbers. Some species are a little less predictable – or we simply don’t know where their critical areas are. Take southern Kenya’s populations of Indo-Pacific bottlenose dolphins (Tursiops aduncus) for instance. Apparently these critters are the most abundant of the marine mammals in Kenya’s Kisite-Mpunguti MPA. Abundance does not mean we know much about them though. The species is listed as data deficient on the IUCN Red List. Continue reading Protecting Kenya’s dolphin habitat
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?
These weird looking things are plankton – from the genus Ancyrochitina to be a little more precise. They are also fossils – approximately 415 million old, from a period known as the late Silurian. That’s pretty cool in itself (at least I think so), but what makes this really interesting is that the individual on the left is malformed, whilst the one on the right is ‘normal’. What is even more interesting than that, is that these malformations coincide with the initial stages of extinction events.
Led by Thijs Vandenbroucke (researcher at the French CNRS and invited professor at Universiteit Gent | Ghent University) and Poul Emsbo (US Geological Survey), an international team of researchers have taken a look at these malformed (known as ‘teratological’) fossil plankton. They wanted to find out what was causing these malformations. Continue reading What 415 million year old fossil plankton tells us about heavy metal pollution and extinction
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
At 9 foot long, not including the tail, tiger shark (Galeocerdo cuvier) Harry Lindo is not exactly on the small side. It’s not Harry’s size that is exciting scientists and shark enthusiasts, nor a photograph taken in 2009 by Ian Card showing a shark – suspected to be Harry, trying to eat a 150 lb juvenile tiger shark off the coast of Bermuda. Between 2009 and 2012 researchers tagged 24 tiger sharks with satellite transmitters in the Challenger Bank, which lies just off Bermuda in the Atlantic Ocean. In study lead by James Lea (The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center) and team of international collaborators, those shark movements have been compiled and analysed. Harry, it turns out, is one heck of an ocean wanderer. In just over 3 years Harry swam over 44,000 kilometres – that’s more than the circumference of the Earth (just over 40,000 kilometres). Harry’s track is the longest recorded for a tiger shark, and probably the longest ever published for any shark species.
Continue reading The travelling life of the tiger shark