The coolest story in this issue is the all seeing-eye that sea-urchins apparently have, using light sensitive detectors on the tips of each of their tube feet, which are distributed all around their body! Less good is the prediction of a global marine mass extinction event. Otherwise, a few groups are publishing genetic studies increasing our understanding of how marine organisms biomineralise carbonates. Quite imporant given the expected increase in ocean acidification.
This issue we see that tides keep species apart – or at least prevent the different strains of the ubiquitous seaweed Fucus spp. from all merging into one species! We also see that iron rich waters result in changes to benthic communities and get an insight into how sponges form glass skeletons – a feat of materials engineering that has always amazed me. The tone is decidedly more serious in our Fisheries section, with a link to graphics showing just how much our fish stocks have declined over the last century. Actually ‘declined’ is not nearly a strong enough word for it. ‘Wiped out’ would be a little closer to the mark.
It has been a while, and there is a lot to go through – so best start with some light browsing! – In Science we’ve got links to a super set of marine life photos, plus an amusing look at cnidaria from the guys at Deep Sea News. The section ends with new takes from molecular biology on the flagella and the mitochondrion – fundamental building blocks of cells.
In conservation we look at attempts to model population dynamics across a patchwork of marine reserves. This kind of understanding is essential for planning effective reserves, as if reserves are too small, or the gaps between them are too large, then they will not protect all of the species within them from over exploitation. This section ends with a look at how well displaced populations survive – as aliens in the Med or the Caribbean, or displaced benthic faunal communities.
Fisheries has an interesting couple of articles on cod fishing in the Baltic – I had full access to the PLoS 1 journal article, and that appeared to say that fisheries, seals and cod could co-habit, though there would be problems. The ScienceDaily headline is a lot more strident, in saying that seals will be the financial ruin of small fishermen. Otherwise there is a paper drawing our attention to the possibility that fisheries and climate may not be independent variables. If this is that case it will make modelling fish stock that bit more challenging…
In fact there is a second link between fisheries and climate change this issue, with news that slow growing fish in the Tasman Sea are being adversely effected by temperature rise – the Tasman Sea has increased in temperature by 2°C in the last 60 years. Thankfully the Weddel Sea has only warmed by 0.6°C, but this still represents an enormous amount of heat entering the Southern Oceans from our warming climate. To ensure there is no silver lining in this issue, we learn that bacteria are the true rain makers.
Usually we start the science section with stories from the vertebrates, and work ‘down’, in a blatant piece of species-ism. This time the anemones float to the top, however, with reports of how the corals might have evolved, and the id of one of the chemicals that induces their free-floating larvae to settle down. We end the section with a series of parties with the world’s largest vertebrates.
Fisheries and exploitation has a report about fishermen being paid to collect plastic. Sounds environmentally beneficial? We’re not sure how the collection will work, as while there is a vast amount of plastic waste at sea, is is usually in small fragments and not very concentrated, making for a very energy intensive clean-up. A skimming exercise that would remove small fragments will also remove many of the small invertebrates and plankton that form an essential part of the food chain… It will be interesting to see if there are any benefits from this bit of horse-trading.
No limit to growth? – This is the surprising conclusion from studies on reef ecosystems, where it is found that total productivity continues increasing as the biological diversity on the reef increases. The broader implication for marine conservation management is that it is important to maintain balance across the widest possible diversity of life in the ecosystem.
Otherwise in this issue we see reasons not to be popular – if your a Weddell seal, and your popularity is as a snack for orcas. Also we get a glimpse of the slow lives of deep corals – which have led blameless, if rather uneventful, lives since the times of the Roman emperors, only to be killed by the recent oil spill in the Gulf of Mexico. There are no places left on the planet that can claim to being untouched by human activity. We must understand our impact better, and take responsibility for our actions – our ancestors will be able to read the records of our crimes in the sediments of the deep seas…
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This issue’s worrying news is of an oil spill that has devastated two islands in the Tristan da Cunha archipelago. Otherwise we have cutbacks, and separated populations, watching sharks get spruced up, and an indication that water fleas do have a history…
In our final article you are warned to slap on sun block now if you live in the Northern Hemisphere, due to a hole in the ozone layer. This problem is set to disappear by the end of the century, however, so it is one climatic problem we won’t be handing over to our grandchildren to solve.
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In marine science this issue, most of our articles relate to how phisico-chemical environment influences the distribution of species. I particularly liked the way the bio-geographical history of the North Atlantic has been revealed through the mDNA of the rough periwinkle. Conservation issues cover cetaceans, coral and cod. Our first article in fisheries raises some questions about the sustainability of invertebrate fisheries. Finally, new estimates suggest that ocean currents (rather than biological activity) are more important in removing carbon from surface waters in the North Atlantic.
We start this issue with a look at a new species of archaea – where we learn how difficult it is to find out anything specific about these organisms. We put phytoplankton on ice, and in ice, use them to make pretty patterns and find them hard to kill; unlike blue sharks, which just wind up dead by accident.
Our conservation section starts with a look at alien species and threat networks, and has news of a new marine protected area off Costa Rica, before links to some personal accounts of manatees and the sex life of groupers (amongst other subjects).
We have the usual crop of articles involving DNA sequencing this issue – but I can offer you a link to Deep Sea News promising to demistify some of this – so that is where we start. DNA sequencing of a brown-tide algae helps to show how it can form these potentially harmful algal blooms. Our article on cryptic dolphins, however, uses isotope analysis to show that two sub-species are feeding on very different prey that they are finding in different locations. We pick up on isotope analysis again in pollution, where 7Be is used to track global pollution and rainfall – but no formal climate change section on this occasion…
In this week’s science section the life history of the Nautilus is being revealed. It proves to be an animal with a long life span, and low fecundity, so in severe danger of becoming the once and future fossil, if it is placed under much pressure. On a more aggressive note, female squid select their males by proxy – encouraging them to fight it out amongst themselves for the privilege of passing on their genes.
A couple of videos this week in the fisheries and exploitation section. These come from the HMAP (History of Marine Animal Populations) project, which endeavours to quantify what the ocean food web looked like before we had such a dominant, and apparently disastrous, impact.
Finally in climate change we have a couple of reports showing how plankton can be used to monitor ocean circulation patterns – past and present.
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