Marine science update 5th May 2011

May 5th, 2011

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.

Marine science

Dahlia anemone photo'd on Lochaline Wall in April 2008.
Dahlia anemone (~15cm diameter).
From little Urticina great corals grow: Scientists have observed that many of the young of the dahlia anemone (Urticina felina) are chimeric – i.e. fused from more than one embryo. The chimeras grow more quickly than normal young, and develop into an adult that is morphologically very difficult to distinguish from them. The perceived advantage in this type of development may help explain the evolution of the large numbers of colonial cnidarians, including the hard and soft corals, that we see today. Proc. Roy. Soc. B, March 2011 via NewScientist (print edition).

Sit down! A chemical cue used by the coral Acropora millepora to determine whether or not to settle down has been identified. The chemical, tetrabromopyrrole, is produced unintentionally by bacterial biofilms that presumably grow on particularly desirable bits of real estate.
Tebben J, Tapiolas DM, Motti CA, Abrego D, Negri AP, et al. (2011) Induction of Larval Metamorphosis of the Coral Acropora millepora by Tetrabromopyrrole Isolated from a Pseudoalteromonas Bacterium. PLoS ONE 6(4): e19082. doi:10.1371/journal.pone.0019082

Quick change: Certain groups of pup-fish have been observed undergoing very fast processes of evolution. They seem to be changing their jaw structures to respond to available food [perhaps a bit like Darwin’s finches?] ScienceDaily (May 1, 2011)

Un-starfish: Report of a starfish species that has forgotten how to grow up, and remains stuck in its juvenile form. The starfish had originally been thought to be an example of a new order of animals… ScienceDaily (May 2, 2011)

Thermal shorts: Cassin’s auklet, a mall sea bird from the North Pacific doesn’t loose heat as quickly as some larger sea birds. ScienceDaily (May 2, 2011)

The quick and the dead: We don’t think of snails as being especially energetic, but apparently modern marine snails consume twice the calories of their relatives in the Mesozoic. This is probably due to an evolutionary arms race between snail and their predators. ScienceDaily (May 3, 2011)

No limit to growth? – Mora’s article challenging the conventional view of biodiversity from observations of reef fishes (reviewed by us on 9th April 2011) makes it to the cover of PLoS Biology.
(2011) PLoS Biology Issue Image | Vol. 9(4) April 2011. PLoS Biol 9(4): ev09.i04. doi:10.1371/image.pbio.v09.i04

A little local trouble: Evaluation of life in the Faroe-Shetland Channel shows there to be rather more life there than expected from global models, and that this is not ‘typically’ distributed. [Models are essential to any attempt to understand the marine ecosystem, but clearly we need to refine them by looking as well!]
Narayanaswamy BE, Bett BJ (2011) Macrobenthic Biomass Relations in the Faroe-Shetland Channel: An Arctic-Atlantic Boundary Environment. PLoS ONE 6(4): e18602.

Salmon on the shelf: Review of data gathered through fish tracking experiments over the past decade on the Pacific coast of the US and Canada (POST). The paper introduces the techniques used, and looks at how technology has improved over the period.
Jackson GD (2011) The Development of the Pacific Ocean Shelf Tracking Project within the Decade Long Census of Marine Life. PLoS ONE 6(4): e18999. doi:10.1371/journal.pone.0018999

Diversity of phytoplankton: Study shows that when measuring the genetic diversity of phytoplankton a number of markers should be used to avoid getting a biased result.
Shi XL, Lépère C, Scanlan DJ, Vaulot D (2011) Plastid 16S rRNA Gene Diversity among Eukaryotic Picophytoplankton Sorted by Flow Cytometry from the South Pacific Ocean. PLoS ONE 6(4): e18979. doi:10.1371/journal.pone.0018979

Warm water survivor? Temperature influences growth and selective mortality of reef fishes.
Rankin TL, Sponaugle S (2011) Temperature Influences Selective Mortality during the Early Life Stages of a Coral Reef Fish. PLoS ONE 6(5): e16814. doi:10.1371/journal.pone.0016814

Introduction to metagenomics: Sifting through the fluff in the ocean’s back pocket with Dr Bik in Deep Sea News, April 26th, 2011

Whale party: Observation of large numbers of humpbacked whales (Megaptera novaeangliae) congregating in the Southern Ocean to feed on vast numbers of krill.
Nowacek DP, Friedlaender AS, Halpin PN, Hazen EL, Johnston DW, et al. (2011) Super-Aggregations of Krill and Humpback Whales in Wilhelmina Bay, Antarctic Peninsula. PLoS ONE 6(4): e19173. doi:10.1371/journal.pone.0019173

Right whale party: Endangered right whales (in the family Balaenidae) are rather susceptible to being hit by ships in the Gulf of Maine. It appears that they are congregating to feed on swarms of copepods as they migrate from shallow to deep water during the day. It appears that the copepods prefer to surface during the night, to avoid predation, but this means that the feeding whales are on the surface in conditions when ship captains cannot see to avoid them. ScienceDaily (Apr. 27, 2011)

Whale shark party: Usually perceived as being solitary, it appears that whale sharks, Rhincodon typus, also have seasonal gathers.
de la Parra Venegas R, Hueter R, González Cano J, Tyminski J, Gregorio Remolina J, et al. (2011) An Unprecedented Aggregation of Whale Sharks, Rhincodon typus, in Mexican Coastal Waters of the Caribbean Sea. PLoS ONE 6(4): e18994. doi:10.1371/journal.pone.0018994

Listening in to beaked whales (party-ing?): An acoustic array in the Bahamas has been used to follow vocalisations by beaked whales. The study shows how the types of noise made correlate with activity in the area, and may help evaluate how man-made noise is impacting the whales.
Hazen EL, Nowacek DP, St. Laurent L, Halpin PN, Moretti DJ (2011) The Relationship among Oceanography, Prey Fields, and Beaked Whale Foraging Habitat in the Tongue of the Ocean. PLoS ONE 6(4): e19269. doi:10.1371/journal.pone.0019269


How to approach biodiversity?
Ellis SL, Incze LS, Lawton P, Ojaveer H, MacKenzie BR, et al. (2011) Four Regional Marine Biodiversity Studies: Approaches and Contributions to Ecosystem-Based Management. PLoS ONE 6(4): e18997. doi:10.1371/journal.pone.0018997

Absolutely Baltic: How do you go about assessing the environmental health of a bit of ocean? – This study attempts to answer this question with respect to the Baltic. A number of indicators were used, such as biodiversity, eutrophication, hazardous substances, fish safe to eat, radioactivity. Each was quantified relative to a set target level, and the proportion of the system with good, bad or indifferent status in each indicator scale plotted. This permitted trends in the ecosystem to be viewed over given time periods, and highlights the concern with eutrophication of the Baltic.
Ojaveer H, Eero M (2011) Methodological Challenges in Assessing the Environmental Status of a Marine Ecosystem: Case Study of the Baltic Sea. PLoS ONE 6(4): e19231. doi:10.1371/journal.pone.0019231

Proteins predict invasion success? Can tolerance at the cellular level, which can be quantified by the expression of heat-shock proteins, translate into a super-fit organism that can out-compete the natives?
Zerebecki RA, Sorte CJB (2011) Temperature Tolerance and Stress Proteins as Mechanisms of Invasive Species Success. PLoS ONE 6(4): e14806. doi:10.1371/journal.pone.0014806

Fisheries and exploitation

Fishing for plastic: To ease pressure on fishing stocks, whilst retaining work in fisheries, the EU have come up with a plan to pay fishermen for recovering plastic. The plan is seen as a sop for fishermen who are to be banned from discarding edible fish at sea. Fiona Harvey in The Guardian 5th May 2011

Recuperation period: We need to know how long marine ecosystems take to recover after damage – usually the cause is human activity, either fisheries or pollution – but the recovery period helps us work out how rapidly we can return to exploiting the resource. In this case, however, the cause was natural, a 9.2 magnitude earthquake in Alaska. This study indicates that it took 26 years for the invertebrate community in Prince William Sound to recover from the event. ScienceDaily (Apr. 25, 2011)

Damned lies: Deep sea news takes issue with calls for fishing regulations to be relaxed. Eric Heupel in Deep Sea News, May 3rd, 2011

Fish liver: It seems that the livers of most edible fish contain beneficial fatty acids in the omega 3 family, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Commonly only cod livers are processed as a health food supplement. ScienceDaily (Apr. 28, 2011)


It does get worse: Mercury is usually released as relatively harmless inorganic salts from coal burning and other industries. This study confirms that after entering seawater, mercury is slowly converted into organo-mercury compounds. These compounds are fat soluble, and are accumulated in marine organisms, reaching potentially dangerous levels towards the top of the food chain (which is usually us). ScienceDaily (Apr. 27, 2011)

7 hours: About how long the oil from the spill would have lasted in the US economy if it had been refined. A nice video via Deep Sea News. Can you reduce your impact? Miriam G in Deep Sea News, April 27th, 2011

Climate change

The seaweed barometer: This study on Fucus vesiculosus or bladder wrack (very common around the UK coastline) shows that small changes in physical and chemical conditions, such as a change in temperature, can upset complex ecosystems, overturning previous regimes. ScienceDaily (May 3, 2011)

How might climate change effect loggerhead sea turtle (Caretta caretta) nesting?
Van Houtan KS, Halley JM (2011) Long-Term Climate Forcing in Loggerhead Sea Turtle Nesting. PLoS ONE 6(4): e19043. doi:10.1371/journal.pone.0019043

Posted in Conservation, Marine science update, Science