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.

Marine science

Another World: A selection of marine life photographs by Alexander Semenov on Photography Served. Absolutely stunning!

The manga of marine life: Some of the interesting life-history tricks of jellyfish By Kevin Zelnio in Deep Sea News, May 22nd, 2011.

Solving cryptic clues: They look alike, they eat the same things, they use the same ecological niches – but they are different species. Molecular biology is turning up increasing numbers of these cryptic species in the marine ecosystem. More surprisingly cryptics often cohabit, with apparently stable populations in the same region. Generally competitive systems don’t work out, as one species tends to dominate, and the other disappears. The model here, however, shows that even for species with identical competitive fitness (β), and invader can gain a foothold by reducing its investment in sex. A lone invader isn’t interested in the locals, so will put all of its effort into growth. Only when enough invaders appear will they start to mate, and be competing on the same playing field as the dominant population. Under these circumstances two populations can co-exist. This model relies on mating signals being species-specific. The authors also claim that diapause costs can also lead to stable two species populations.
Montero-Pau J, Serra M (2011) Life-Cycle Switching and Coexistence of Species with No Niche Differentiation. PLoS ONE 6(5): e20314. doi:10.1371/journal.pone.0020314

Impossible dives: Emperor penguins can dive for 20 minutes beneath the Antarctic ice without needing to surface for air. This study shows how oxygen is used up in the three stores – lungs, blood and muscle – to enable the bird to achieve this phenomenal endurance. ScienceDaily (May 16, 2011)

The seal’s whiskers: The whiskers of harbour seals (Phoca vitulina) are so sensitive that they can pick up the wake of a swimming fish 35 seconds after it has passed by, and work out its size and shape from this information! ScienceDaily (May 16, 2011)

Decapod diversity: The decapods include many of of the most commonly encountered, and most commercially valuable, crustacean species – crabs, lobsters, langoustines and crayfish. Despite this, their genetic diversity, particularly at a regional level, is almost completely unexplored. In this study cytochrome c oxidase subunit I (COI) regions of over 100 species are sequenced (<500 individuals). The COI region is present in all mitochondria - from plants and animals - and is commonly used for identifying organisms, and working out how related they are to each other. The study showed that the COI sequence can normally be used to identify species within decapoda. Further it provides some interesting insights into how diverse each family within the decapoda are. Matzen da Silva J, Creer S, dos Santos A, Costa AC, Cunha MR, et al. (2011) Systematic and Evolutionary Insights Derived from mtDNA COI Barcode Diversity in the Decapoda (Crustacea: Malacostraca). PLoS ONE 6(5): e19449. doi:10.1371/journal.pone.0019449 Worms in the pit: A study of nematode populations in channels leading into the Porcupine Seabight, off the SW tip of Ireland. The study looks at which factors influence the nematode population structure.
Ingels J, Tchesunov AV, Vanreusel A (2011) Meiofauna in the Gollum Channels and the Whittard Canyon, Celtic Margin—How Local Environmental Conditions Shape Nematode Structure and Function. PLoS ONE 6(5): e20094. doi:10.1371/journal.pone.0020094

Remipede review: Since its discovery in 1981, a total of 24 species have now been included within the class Remipedia – segmented crustaceans that tend to live in caves, and are superficially similar to centipedes…
Neiber MT, Hartke TR, Stemme T, Bergmann A, Rust J, et al. (2011) Global Biodiversity and Phylogenetic Evaluation of Remipedia (Crustacea). PLoS ONE 6(5): e19627. doi:10.1371/journal.pone.0019627

Species of sea lettuce: Sea lettuces are not easy to identify, as they are quite plastic, adopting different forms in response to environmental conditions. This study attempts to identify a free-floating bloom of Ulva that occurred in the Yellow sea in 2008. The study provides some key information that may assist with future identifications (see discussion section). In particular it suggests that branching is a key characteristic differentiating between U. prolifera (branched) and U. linza (unbranched).
Hiraoka M, Ichihara K, Zhu W, Ma J, Shimada S (2011) Culture and Hybridization Experiments on an Ulva Clade Including the Qingdao Strain Blooming in the Yellow Sea. PLoS ONE 6(5): e19371. doi:10.1371/journal.pone.0019371
Hot iron: Geothermal vents release ecologically important amounts of iron into the oceans in the form of stable sulphide nano-particles. The particles form a stable suspension allowing the iron to be transported considerable distances from its source. ScienceDaily (May 10, 2011)

Watching kelp from space: Free Landsat 5 images were used to map kelp growth on the Californian coast, and see how this changed with sea conditions. ScienceDaily (May 18, 2011)

Urea cycle in diatoms: It appears that diatoms (single celled plants) are able to produce urea, a trick previously though to be restricted to animals. Diatoms may use this ability to keep hold of nitrogen and carbon, enabling them to survive in nutrient poor waters. ScienceDaily (May 12, 2011)

Mussels change genes with the seasons: The cells of most animals contain a copy of the complete genome, but most of the instructions are switched off at any one time (these genes are ‘not expressed’). This paper looks at gene expression in the digestive system and gonads of the mussel Mytilus galloprovincialis, and how this changes through the year.
Banni M, Negri A, Mignone F, Boussetta H, Viarengo A, et al. (2011) Gene Expression Rhythms in the Mussel Mytilus galloprovincialis (Lam.) across an Annual Cycle. PLoS ONE 6(5): e18904. doi:10.1371/journal.pone.0018904

The coral clock: Four molecular clock genes have been discovered in the stony coral Favia fragum. Corals are known to have a diurnal rhythm, as well as being able to track the lunar cycle, which helps them organise mass spawning events. The clocks identified control diurnal responses, but not lunar spawning cycles.
Hoadley KD, Szmant AM, Pyott SJ (2011) Circadian Clock Gene Expression in the Coral Favia fragum over Diel and Lunar Reproductive Cycles. PLoS ONE 6(5): e19755. doi:10.1371/journal.pone.0019755

Genome reconstructed from single cell: Sophisticated sorting techniques have allowed scientists to pick out individual single celled animals for genetic analysis. This, and similar work reported previously, will allow us a glimpse of the private lives of cells. ScienceDaily (May 8, 2011)

Shining a light on bacteria: The bacterium Pelagibacter ubique may be one of the smallest living organisms on the planet, but in the summer they make up to 50% of the total number of living cells in the oceans! Its primary role appears to be recycling carbon, making this available to phytoplankton, and so is an essential contributor to oxygen production and the carbon cycle… Pelagibacter produce pigments that enable them to use sunlight to drive proton pumps, but this ability seemed to offer no advantage to the organism. This paper shows that they have a role in protecting Pelagibacter under conditions of carbon starvation, when it can use sunlight to maintain cellular function without depleting its carbon reserves. [We tend to think of organisms as being plants or animals – with this half way house towards photosynthesis, micro-organisms again challenge our pre-conceptions!]
Steindler L, Schwalbach MS, Smith DP, Chan F, Giovannoni SJ (2011) Energy Starved Candidatus Pelagibacter Ubique Substitutes Light-Mediated ATP Production for Endogenous Carbon Respiration. PLoS ONE 6(5): e19725. doi:10.1371/journal.pone.0019725

The life and times of the coelocanth, a review. Deep Sea News, May 16th, 2011

Moving story: Trace fossils indicate that algal mats may have produced enough oxygen in shallow waters to allow small multicellular animals to graze within them up to 555 million years ago. ScienceDaily (May 15, 2011)

Bugs in gear: how bacteria shift gears for their flagella, allowing them to stop and change direction. [Flagellae are also common amongst many single celled phytoplankton, such as the dynoflagellates, so this is a pretty fundamental discovery about motion at this scale]. There is also a brief review of this paper.
Minamino T, Imada K, Kinoshita M, Nakamura S, Morimoto YV, et al. (2011) Structural Insight into the Rotational Switching Mechanism of the Bacterial Flagellar Motor. PLoS Biol 9(5): e1000616. doi:10.1371/journal.pbio.1000616

Dilithium has nothing to do with it: The powerhouse of the eukaryotic cell is the mitochondrion. This is derived from a free-living bacterium that took up an endosymbiont role about 1.5 billion years ago. The process of inclusion within the cell has required a number of fundamental changes in both symbiont and host. Amongst these was the loss of much of hte genetic material of the symbiont, making it reliant on the host for basic raw materials. In this paper the mechanism by which proteins are imported into the mitochondrion is elucidated in the filamentous brown algae Ectocarpus.
Delage L, Leblanc C, Nyvall Collén P, Gschloessl B, Oudot M-P, et al. (2011) In Silico Survey of the Mitochondrial Protein Uptake and Maturation Systems in the Brown Alga Ectocarpus siliculosus. PLoS ONE 6(5): e19540. doi:10.1371/journal.pone.0019540

Conservation

How your reserves connect: This model attempts to work out how organisms move between a network of reserves, focussing on two transport mechanisms – larval dispersal, and adult movement. It makes some interesting predictions on how these parameters interact with the size of the reserves to result in sustainable populations, or population collapse.
Grüss A, Kaplan DM, Hart DR (2011) Relative Impacts of Adult Movement, Larval Dispersal and Harvester Movement on the Effectiveness of Reserve Networks. PLoS ONE 6(5): e19960. doi:10.1371/journal.pone.0019960

How connected are your reserves? This study, of genetic structure of populations in a series of marine parks along the coast of New South Wales (Australia), shows that connectivity between populations of marine organisms is very dependent upon the nature of the organism concerned.
Coleman MA, Chambers J, Knott NA, Malcolm HA, Harasti D, et al. (2011) Connectivity within and among a Network of Temperate Marine Reserves. PLoS ONE 6(5): e20168. doi:10.1371/journal.pone.0020168

The drifters: A lot of marine species spend a period of their lives drifting in the plankton, the amount of time reef fish spend in this stage does not, however, correspond to their eventual geographic distribution. Researchers suggest that the larvae have a minimum drifting period that allows them to reach all of the available reef habitats. [A longer time spent drifting may reflect a need to be larger to capture a habitat on the reef?]. ScienceDaily (May 10, 2011)

A richness of mammals: A model estimating current biodiversity of marine mammals, based on their observed climatic range, and attempting to predict future biodiversity in response to climate change. Current biodiversity estimates were checked against records of cetacean sightings.
Kaschner K, Tittensor DP, Ready J, Gerrodette T, Worm B (2011) Current and Future Patterns of Global Marine Mammal Biodiversity. PLoS ONE 6(5): e19653. doi:10.1371/journal.pone.0019653

Stranded at land: Sperm whale (Physeter macrocephalus) mass strandings are rare in the Mediterranean, six events having occurred on the Adriatic coast of Italy since 1555. On the occasion of December 2009, it appears that that the whales mistook their direction, though seismic surveys may have contributed to their confusion.
Mazzariol S, Di Guardo G, Petrella A, Marsili L, Fossi CM, et al. (2011) Sometimes Sperm Whales (Physeter macrocephalus) Cannot Find Their Way Back to the High Seas: A Multidisciplinary Study on a Mass Stranding. PLoS ONE 6(5): e19417. doi:10.1371/journal.pone.0019417

Turtle’s star turn: Using satellite tracking systems to follow olive ridley sea turtles (Lepidochelys olivacea) from Mayumba National Park, Nyanga Province, Gabon, Africa. System allowed researchers to map activity of these turtles in the region.
Maxwell SM, Breed GA, Nickel BA, Makanga-Bahouna J, Pemo-Makaya E, et al. (2011) Using Satellite Tracking to Optimize Protection of Long-Lived Marine Species: Olive Ridley Sea Turtle Conservation in Central Africa. PLoS ONE 6(5): e19905. doi:10.1371/journal.pone.0019905

Taming the lion: Lionfish of the species Pterois volitans and Pterois miles have invaded the Western Atlantic Ocean, Caribbean Sea and Gulf of Mexico. This has prompted studies on how they might be removed from the area, ni case they cause damage to the pre-existing ecology. Calculations suggest that they would redover very quickly from a partial removal, and a sustained take of between 35 and 65% of the population would be required to eradicate them.
Barbour AB, Allen MS, Frazer TK, Sherman KD (2011) Evaluating the Potential Efficacy of Invasive Lionfish (Pterois volitans) Removals. PLoS ONE 6(5): e19666. doi:10.1371/journal.pone.0019666

Aliens in the Med: Over 900 alien species have now been recorded in the Mediterranean Sea, and they are occurring in such numbers that the food chain is changing to accommodate them. ScienceDaily (May 23, 2011)

Climate change in the laboratory: A series of international experiments in which benthic communities were relocated, to simulate climate change. Subsequently the rate at which the displaced community changed – usually back to its original community structure – was measured. The rate, and hence the robustness of the displaced community, is found to depend upon both the number of species in teh community and its functional richness in terms of the range of body sizes, growth forms, trophic levels and modularity.
Wahl M, Link H, Alexandridis N, Thomason JC, Cifuentes M, et al. (2011) Re-Structuring of Marine Communities Exposed to Environmental Change: A Global Study on the Interactive Effects of Species and Functional Richness. PLoS ONE 6(5): e19514. doi:10.1371/journal.pone.0019514

Fisheries and exploitation

Cod sealed out? Models of the Baltic Sea have been used to try and work out how cod stocks will change as a result of changes in exploitation levels and salinity. The predictions indicate that seals have a far lower impact on cod recovery than either exploitation or salinity, and that a sustained recovery in both seal populations and cod is possible, though not easy to achieve.
MacKenzie BR, Eero M, Ojaveer H (2011) Could Seals Prevent Cod Recovery in the Baltic Sea? PLoS ONE 6(5): e18998. doi:10.1371/journal.pone.0018998
Science Daily runs the headlines that protecting seals will destroy small fishing businesses based on Swedish research. ScienceDaily (May 10, 2011)

Three generations in captivity: The Marine Culture facilities in Mazarrón have succeeded in rearing three generations of Atlantic bonito (Sarda sarda) in captivity. ScienceDaily (May 20, 2011)

Fisheries and climate linked: Studies of the Mediterranean hake (Merluccius merluccius) fisheries show that the annual catch of fish oscillates in step with the climate. In contrast, when fisheries were not over-exploited, no oscillation in fish stock is observed. The problem is that fisheries concentrate on a sector of the fish population (the largest and fittest fish), the loss of which makes the entire population less able to survive in a dynamic environment. This indicates that the impact of fisheries and that of climate are linked, and cannot be studied separately. ScienceDaily (May 16, 2011)

Useful cyanobacteria: The genetic code of blue green algae Lyngbya spp. is being decyphered, it appears that many sub-species are not as useful as first thought, though the entire family should still unlock a pharmaceutical treasure house. ScienceDaily (May 10, 2011)

How good is that fish? An automated mechanism for measuring the amounts of astaxanthin – a natural pigment that consumers associate with fresh fillets of rainbow trout – has been developed.
Dissing BS, Nielsen ME, Ersbøll BK, Frosch S (2011) Multispectral Imaging for Determination of Astaxanthin Concentration in Salmonids. PLoS ONE 6(5): e19032. doi:10.1371/journal.pone.0019032

Pollution

Shit takes over: Nitrogen run-off is a serious component of coastal pollution, leading to eutrophication and mass die-offs. Over recent years improvements to agricultural practices in the Caribbean have resulted in this reducing in importance relative to nitrogen from sewage water. ScienceDaily (May 17, 2011)

Yuk, I’m sick! Biomarkers indicating poisoning by hydrocarbons are being found in haddock and Cod caught in the open North Sea. The source of the hydrocarbons is probably oil production.
Balk L, Hylland K, Hansson T, Berntssen MHG, Beyer J, et al. (2011) Biomarkers in Natural Fish Populations Indicate Adverse Biological Effects of Offshore Oil Production. PLoS ONE 6(5): e19735. doi:10.1371/journal.pone.0019735

Whales and dolphins soak it up: Persistent organic pollutants are bi-products of human industrial activity. They are concentrated up the food chain, and are found at quite high levels in whales and dolphins. This study shows that the levels of pollution found in these animals is dependent upon where they forage – with those living closer to human habitation picking up a bigger dose. ScienceDaily (May 12, 2011)

Are modern organophosphorous pesticides safe? A molecular level investigation of how these interact in mussels.
Canesi L, Negri A, Barmo C, Banni M, Gallo G, et al. (2011) The Organophosphate Chlorpyrifos Interferes with the Responses to 17ß-Estradiol in the Digestive Gland of the Marine Mussel Mytilus galloprovincialis. PLoS ONE 6(5): e19803. doi:10.1371/journal.pone.0019803

Extinction loop-holes: 39 species on the IUCN Red List, and so in imminent danger of extinction, have ranges that intersect the DeepWater Horizon incident area in the Gulf of Mexico, but are not protected by the Endangered Species Act. ScienceDaily (May 12, 2011)

One thing leads to another: Coral larvae (Acropora spp.) that are already stressed by pollution (here Cu concentration) suffer worse when they are also subjected to elevated water temperatures. Survival of larvae is plotted against temperature and Cu concentration.
Negri AP, Hoogenboom MO (2011) Water Contamination Reduces the Tolerance of Coral Larvae to Thermal Stress. PLoS ONE 6(5): e19703. doi:10.1371/journal.pone.0019703

Climate change

Inshore fisheries decline: Increased water temperatures are hitting the growth of long-lived species on the Australian and New Zealand coasts. Water temperatures in the Tasman Sea have increased by 2°C over the last 60 years – one of the most rapid increases in temperature seen in the World. ScienceDaily (May 20, 2011)

Deadzone: Greenhouse oceans in the Late Cretaceous Period are associated with massive marine die-offs. ScienceDaily (May 17, 2011)

Polarstern reports full ahead on global warming: A seven month research cruise by the Polarstern maintaining and monitoring sensors in the Weddell Sea finds a 0.6°C average temperature rise through the entire water column over the last 25 years. This might not seem like much, but given the size of the body of water and its heat capacity… ScienceDaily (May 19, 2011)

A softspot for hard corals: One of the curious things about calcium carbonate is that it becomes more soluble with depth, leading to ‘saturation horizons’ – depths below which the carbonates dissolve [calcite is less soluble than aragonite, so has a deeper horizon depth]. As ocean acidification proceedes it is feared that calcified deepwater scleractinian corals will find it harder to survive at depth, as they will be unable to build their calcareous skeletons.
Miller KJ, Rowden AA, Williams A, Häussermann V (2011) Out of Their Depth? Isolated Deep Populations of the Cosmopolitan Coral Desmophyllum dianthus May Be Highly Vulnerable to Environmental Change. PLoS ONE 6(5): e19004. doi:10.1371/journal.pone.0019004

Plunk-plunk-fizz: Atomic force microscopy watches whils coccolithophorids dissolve at the acidities predicted for our future oceans. Coccolithophorids are small phytoplankton which are responsible for absorbing a lot of our excess carbon dioxide to make their intricate carbonate shells. ScienceDaily (May 10, 2011)

Icebergs help oceans absorb CO₂: Studies of life on the undersides of ice-bergs in the Southern Ocean indicate that these are where most carbon is fixed, rather than in the surrounding open water. ScienceDaily (May 12, 2011)

1000 year storm: Growth rings from coastal shrubs in the Mackenzie Delta (Northwest Territories) shows that the storm surge in 1999, when seawater inundated much of the coastal region, was unprecedented in the preceding millenium. ScienceDaily (May 16, 2011)

The biology of clouds: Clouds form when water droplets condense out of an atmosphere super-saturated with water. Experiments show, however, that these droplets only form spontaneously at such levels of super-saturation, that we would never be likely to see any clouds on Earth… In practice droplets need something to start them off. Above the oceans this is the chemical dimethyl sulphide (DMS), which is a by-product of bacterial activity decomposing plankton. ScienceDaily (May 12, 2011)