Lots of stuff in this roundup in which we travel in time from an up-to-date science review from the gulf oil spill (handy for next month’s talks!) back to ancient cnidaria. Exciting changes in fisheries protection for the US Pacific fleet, which is to see the number of boats reduced to match the number of fish that can be legally caught. More on the formation of shoals – what is the cost of grouping together for protection? To start, however, a first glimpse into the life of one of the largest groups of marine organisms – the bacteria:

Marine science

Overlooked and undervalued: Microbes are a vital component of the ocean’s ecosystem, but up to now it has been very hard to get a handle on what they are doing. Increasingly, however, appropriate DNA micro-arrays can be used to look directly at what genes are being expressed in microbial communities as a whole, and so get a handle on what they are up to. In this study gene expression was monitored in the Columbia river estuary both in spring and late summer, and at a number of locations within the halocline, and these are compared against basic physical and chemical parameters.
The results give an idea of the species active, and the type of activity ongoing in the estuary at these times. They indicate that activity is in part governed by availability of light (essential for autotophic bacteria, which dominate summer samples), and nutrients in the fresh water run-off. There is a strong seasonal component to what is happening, though bacterial populations remain high and diverse throughout the year.
Smith MW, Herfort L, Tyrol K, Suciu D, Campbell V, et al. (2010) Seasonal Changes in Bacterial and Archaeal Gene Expression Patterns across Salinity Gradients in the Columbia River Coastal Margin. PLoS ONE 5(10): e13312. doi:10.1371/journal.pone.0013312

Aeons of anemones: The Chinese fossil record has been analysed to find some of the earliest ancestors of modern cnidarians. Well preserved soft tissues were found in phosphorite deposits from the early Cambrian period (ca 540MYA), the nature of the fossilisation process in these sediments is such that preservation down to the cellular level is possible. Micrographs show the features we are familiar with in modern anemones.
Han J, Kubota S, Uchida H-o, Stanley GD Jr, Yao X, et al. (2010) Tiny Sea Anemone from the Lower Cambrian of China. PLoS ONE 5(10): e13276. doi:10.1371/journal.pone.0013276

How does latitude influence marine diversity? This study looks at seaweeds (macro-algae) living in shallow marine environments in the Northern Hemisphere. Only 69 sites were considered, and there is considerable scatter in results, but they do show a trend towards increased diversity and biomass with increased latitude. If seaweed is looked at by depth-range, however, then the picture becomes clearer, with noticeable increases in diversity in the intertidal region. As the depth increases, however, the pattern starts becomes less clear. results are less statistically significant for the 10m depth region, but there does appear to be a reversal, with greater diversity low latitudes. Biomass broadly follows diversity, but results are less statistically reliable. This paper touches on a number of exciting concepts – what drives diversity? – are diversity and biomass directly related? Great fun, and not too difficult to replicate, as the study uses a quadrat, a low precision (+/-1g) balance and a bit of ID skill…
Konar B, Iken K, Cruz-Motta JJ, Benedetti-Cecchi L, Knowlton A, et al. (2010) Current Patterns of Macroalgal Diversity and Biomass in Northern Hemisphere Rocky Shores. PLoS ONE 5(10): e13195. doi:10.1371/journal.pone.0013195

Dinoflagellate family tree refined: Dynoflaggellates are one of the important groups of marine phytoplankton, but how the different species are interrelated is difficult to quantify, even with genetic analysis techniques. This latest study looks at differences in how heat shock-proteins are coded between species. It suggests that the group has been subject to a ‘recent’ explosive phase of diversification, but I think more work remains to be done here before the tree is fully elucidated…
Hoppenrath M, Leander BS (2010) Dinoflagellate Phylogeny as Inferred from Heat Shock Protein 90 and Ribosomal Gene Sequences. PLoS ONE 5(10): e13220. doi:10.1371/journal.pone.0013220

We can see you: A continuous flow cytometer, called “SeaFlow”, has been developed that allows RV‘s to continually monitor the water they are sailing through for phytoplankton. The new cytometer can monitor thousands of phytoplankton per second. The researchers claim that this is an important advance, in that it gives us a better handle on phytoplankton concentrations, and will allow us to identify phytoplankton ‘hotspots’, more easily than has previously been possible. ScienceDaily (Oct. 12, 2010)

Swimming plankton mix it up: It is quite hard for a small organism to get about, but now researchers are finding that blooms, or dense aggregates of plankton actually tend to work together. AS one organism starts swimming, it sets up a complex flow pattern in the water around it. This in turn can be felt by surrounding plankton, who can change their activity to increase the movement. This joint activity can result in considerably more mixing in the water than would otherwise occur, and the large numberf of organisms involved results in this being quite important in the oceans’ carbon cycles, and in the transfer of heat, from atmosphere to ocean, and within the ocean itself. ScienceDaily (Oct. 12, 2010)

Volcanic plankton bloom: It is claimed that iron laden ash from the 2008 eruption of the Kasatochi volcano in the Aleutian Islands (between Kamchatka and Alaska) resulted in a massive phytoplankton bloom in the northern Pacific. ScienceDaily (Oct. 5, 2010)

Hagfish get horny: Hagfish are amongst the most primitive vertabrates, and their sex-life has remained a mystery – until now! Now we know at least one of the reproductive hormones involved, a gonadotropin, which may shed light on how sex evolved in the vertebrates as a whole… ScienceDaily (Oct. 5, 2010)

What has a microbe in every bite? There are estimated to be as many as 38,000 different kinds of microbe in every litre of seawater, with a total of up to 1 billion different strains of microbe in total in the world’s oceans. ScienceDaily (Oct. 4, 2010)

Deep-sea reefs in the Med: Corals havebeen discovered growing at 700m depth in the Mediterranean, 30-40km off the Israeli coast. ScienceDaily (Oct. 3, 2010)

Life in the deep: Most of the volume of the world’s oceans is below 200m in depth, with very little sunlight plants are not able to survive. This means that life in most of the world’s water is reliant upon ‘organic snow’, detritus falling from the sunlit shallows… An Empire Lacking Food by Craig McClain in American Scientist 98,6 (2010).

Get out of my hair – parasite transmission in shoals: While shoals provide fish with ‘protection in numbers’, grouping together also exposes them to disease and parasites (I guess much like early human cities). This study quantifies the cost of shoaling, in terms of increased exposure to parasites, in guppies (Poecilia reticulata). They find that female guppies, which shoal more than their male counterparts, suffered a four-fold increase in parasite infection.
Richards EL, van Oosterhout C, Cable J (2010) Sex-Specific Differences in Shoaling Affect Parasite Transmission in Guppies. PLoS ONE 5(10): e13285. doi:10.1371/journal.pone.0013285

Whales bring home the Nitrogen: Previously we’ve reported that sinking whale carcasses are an efficient way of removing carbon from surface waters (Climate change – “Whales in the carbon cycle”). Now we find that whales and other diving mammals may be responsible for bringing nitrogen up from the deeps, back into circulation in shallow waters. Nitrogen is an important trace nutrient, but presumable there must be a lot of carbon coming back up with this?
Roman J, McCarthy JJ (2010) The Whale Pump: Marine Mammals Enhance Primary Productivity in a Coastal Basin. PLoS ONE 5(10): e13255. doi:10.1371/journal.pone.0013255

Iguanas on steroids: The marine iguanas of the Galapagos are periodically subject to extreme environmental stress due to El Niño. Many starve during these events. To first response to stress in the iguanas is to secrete corticosterone, which helps them metabolise proteins, this is useful when a fast response to danger is required, as it gives them energy. If the levels of corticosterone are not reduced quickly, however, the animals deplete their protein reserves, and starve to death. ScienceDaily (Oct. 11, 2010)

Fresh water algal bloom kills sea-otters: Microcystins released by freshwater cyanobacterial bloom have been implicated in the deaths of sea otters on the US west coast. The toxic microcystins are persistent, and concentrated by mussels and other shellfish in the estuary by factors of up to 100x the concentration in the water. At these levels they can become toxic to otters (and presumably any other mammal that eats them).
Miller MA, Kudela RM, Mekebri A, Crane D, Oates SC, et al. (2010) Evidence for a Novel Marine Harmful Algal Bloom: Cyanotoxin (Microcystin) Transfer from Land to Sea Otters. PLoS ONE 5(9): e12576. doi:10.1371/journal.pone.0012576

Lampreys sink their teeth into a hedgehog: Lampreys and hagfish are the only surviving jawless vertebrates (so no teeth). The hedgehog family of signaling proteins controls embryonic development in many organisms, the genes exist in tunicates, hagfish and mammals. This paper demonstrates that lamprey hedgehog (Hh) genes are similar in expression and regulation to those (Shh) genes in zebra fish that control neural development.
Kano S, Xiao J-H, Osório J, Ekker M, Hadzhiev Y, et al. (2010) Two Lamprey Hedgehog Genes Share Non-Coding Regulatory Sequences and Expression Patterns with Gnathostome Hedgehogs. PLoS ONE 5(10): e13332. doi:10.1371/journal.pone.0013332

Conservation

Managing development around coral reefs: This paper sets out a management process for reefs, starting with the definition of the conservation objective (in this instance “to maximize threat reduction to coral reefs”). The second stage identifies the threats, in this instance htese are restricted to those that are of local origin (so not global climate change). Then identify remedies (either manage watersheds by changing the vegetation growing in them, or manage the reefs through controlling fisheries activity). The cost of implementing conservation strategy is then calculated, and finally the likely return on this cost is calculated to determine the best option from competing scenarios.
Klein CJ, Ban NC, Halpern BS, Beger M, Game ET, et al. (2010) Prioritizing Land and Sea Conservation Investments to Protect Coral Reefs. PLoS ONE 5(8): e12431. doi:10.1371/journal.pone.0012431

Checkout that fish: This paper documents the development of a rapid analysis technique for reading DNA barcodes that can be used to identify fish on sale, even in processed food products. It is important to be able to identify species, so that the consumer knows what she’s buying, and endangered species can be protected.
Kochzius M, Seidel C, Antoniou A, Botla SK, Campo D, et al. (2010) Identifying Fishes through DNA Barcodes and Microarrays. PLoS ONE 5(9): e12620. doi:10.1371/journal.pone.0012620

Managing conservation: “Conservation Excellence Model” to be a new framework for managing conservation? The new management strategy is said to allow conservationists to set clearer goals for their projects, to implement and monitor their program more effectively. ScienceDaily (Oct. 12, 2010)

Coral bleaching in Western Caribbean: A major bleaching event appears to be ongoing in the Western Carribean in response to higher than normal water temperatures. ScienceDaily (Oct. 13, 2010)

Some corals will not recover: While corals are in decline due to rising sea temperatures, there was hope that although this was occurring, some corals are already happily adapted to warmer water. As a consequence, it was reasoned, that the symbionts living with these ‘hot corals’ could be transferred to their cold-water bretheren, and permit them to cope with hot water. This report shows that this revival plan is over-simplified, while some individuals in the species studied did take up the new symbiotic algae, the host-symbiont arrangement was unstable and short-lived.
Coffroth MA, Poland DM, Petrou EL, Brazeau DA, Holmberg JC (2010) Environmental Symbiont Acquisition May Not Be the Solution to Warming Seas for Reef-Building Corals. PLoS ONE 5(10): e13258. doi:10.1371/journal.pone.0013258

Marine life on the reef under pressure: Turtles, dugongs and other life on the Great Barrier Reef are under pressure from a range of influences, including fishing, onshore development and pollution. This may reduce their ability to survive climate change. ScienceDaily (Oct. 10, 2010)

Fisheries and exploitation

Scallops on guard: The Cozmino oil terminal will be monitored by a garden of scallops. Scallops filter large amounts of water every day, and tend to pick up pollutants, and store them (a reason why shellfish can be hazardous – see also otter deaths above). Here, however, the scallops can be sampled periodically, to check on water quality in the harbour. The Spill, Monday, October 11, 2010

No deep drilling ban in the UK. Deep-Sea News, October 12th, 2010

Fish fend off diabetes: Studies shoe that fish diets help fend off common ailments such as diabetes. ScienceDaily (Oct. 8, 2010). Before you eat all of the cod-liver oil tablets, however, read the report below…

Fish oil gives you the squits: Fish oil is recommended for healthy joints and has been implicated in improvedcognitive performance. One thing it might not help with though, is digestive performance. This study shows that excess amounts of docosahexaenoic acid (DHA), one of the key active ingredients in fish oil, are related to development of colon cancers and gut inflammation in mice. ScienceDaily (Oct. 5, 2010)

Fisheries protection changes will save money: A new system of premits is being rolled out in the US that will simplify fisheries regulations. The regulations will reduce the numbers of permitted boats by about 50%, and impose percentage limits on each boat – so a permit might allow a vessel to catch 2% of the total permitted catch of a given fish. The new regulations will replace gear, time and regional restrictions previously in force. This is a pretty radical change in how fisheries have been managed in the past, with regulations on mesh sizes, protected regions and so on. It will be interesting to see how cleanly it is implemented (i.e. how many concessions to the old system will happen, making the new one more complex than anticipated) and, most importantly, how it impacts stocks. ScienceDaily (Oct. 5, 2010)

Fish-food from waste fish: Processed heads and tails may find their way into fish and shrimp feed. (Similar to below) ScienceDaily (Oct. 6, 2010)

New fishfood: Another step towards sustainable aquaculture, by developing feeds containing reduced amounts of caught wild fish. ScienceDaily (Oct. 13, 2010)

Pollution

How the spill was handled: This article from the Wall Street Journal suggests that the US administration started out by underestimating the problem, then over-reacted when it became clear that BP could not shut the well down quickly. Locally, interference from posturing politicians resulted in operational confusion and parallysis. Finally, politicians are accused of being too quick to draw a line under the event, and go back to ‘business as usual’. James Herron, The Wall Street Journal, October 7, 2010.

Outcomes of the Gulf oil spill: The Spill asks what has been learnt as a consequence of the Gulf oil spill, as political pressure mounts to re-start oil extraction from deep sea rigs. The Spill, October 06, 2010

State of Gulf beaches: This is an ‘on-the-spot’ report from one of the people engaged in surveying the state of beaches effected by the Gulf Oil Spill. Deep Sea News, October 5th, 2010

No oil here: There does not appear to be any oil in the shallows around the Florida coast, so perhaps hope that there is not an offshore reservoir that can re-contaminate beaches. Deep Sea News, October 12th, 2010

Climate change will not deafen whales: The changes in seawater’s acoustic properties caused by ocean acidification (due to increased levels of carbon dioxide in the atmosphere) will not effect the transmission of noise from shipping. Previously this had been considered a threat, with increased shipping noise likely to cause dificulties for communicating whales. ScienceDaily (Oct. 13, 2010)

Spill the science: An overview of the Deepwater Horizon Principal Investigator conference in October. This conference looked at how existing scientific expertise was mobilised in the immediate aftermath of the accident, and what science has been commissioned in response. Initially it appears that there was little co-ordination, with RV‘s duplicating sampling. Subsequently, there have been difficulties for scientists wanting access to the samples for annalysis. Very large sums of money have been power-hosed into the field since the event, resulting in a large number of research projects being established (for a database of activities and live RSS feed see “The Gulf of Mexico Sea Grant Programs” . Deep-Sea News, October 12th, 2010

Climate change

Sea to get wetter? Climate changes will result in increased evaporation and, consequently, rainfall. This research indicates that there has been a 1.5% increase per year in land run-off through rivers since 1994. This is actually a pretty significant increase in river-flow, caused by higher temperatures over the last decade accelerating the hydrodynamic cycle. ScienceDaily (Oct. 5, 2010)

Coral feels the heat: Most of the world’s oceans are are divided in two, with a layer of sun warmed surface wateroverlying deep waters that are much colder. The transition between warm and cold is often quite abrupt, occurring over a few tens of metres, this transition zone is called a thermocline. SCientists have now been able to track the historic depth of the thermocline int eh Pacific by looking at coral growth. They imply that changes in the depth of the thermocline over the last few decades are driven by global climate change. ScienceDaily (Oct. 13, 2010)

Feeling the heat – cold fish breathe more efficiently: In cold blooded animals, like most fish, increases in temperature tend to increased metabolic rate, and higher oxygen demand. As a consequence, warm fish need more oxygen than cold fish… The Great Barrier Reef spans an enourmous range of latitudes and therefore temperatures. Researchers have found that fish living in the warmer parts of the reef are less able to respond to increased temperatures than those in cooler waters.
Gardiner NM, Munday PL, Nilsson GE (2010) Counter-Gradient Variation in Respiratory Performance of Coral Reef Fishes at Elevated Temperatures. PLoS ONE 5(10): e13299. doi:10.1371/journal.pone.0013299