Shellfish growth stunted by more acidic oceans – the potential harm from ocean acidification is towards the top of the agenda at the moment. In this latest report increased levels of carbon dioxide are implicated in having an effect on shellfish reefs formed by the Olympia oyster. From ScienceDaily (Apr. 20, 2010).

Bivalves used to sense oil pollution: When mussels are exposed to pollution they start to close their shells, and the degree of closure is related to the concentration of polutants in the water. Norwegian company Biota Guard has developed a method for measuring the degree of closure, and so offering a quick and cheap sensor for monitoring discharges from petroleum platforms. From ScienceDaily (Apr. 26, 2010)

Protected reef offers model for conservation: A protected reef in Belize bucks the trend for deterioration and loss of fish stocks seen in neighbouring reefs, and worldwide. From New York Times. April 27, 2010

Ladybirds used as biocontrol agents in Galapagos: Indigenous vegetation on the Galapagos Islands has been suffering from attacks by an introduced insect pest called cottony cushion scale, which had resulted in some species disappearing. This damage appears to have been halted by the introduction of another insect, Rodolia cardinalis, a relative of the ladybird. Rodolia has already been used to reduce infestations of cottony cushion scale insect in California. From ScienceDaily (Apr. 22, 2010)

Should we hold marine mammals in captivity? The US congress is to explore the issues behind keeping marine mammals in captivity. There is growing feeling that entertainment is not enough to justify this practice, and that there must be some meaningful educational outcomes. From PressZoom 2010-04-27.
An important factor starting this debate was the death of a killer whale handler at SeaWorld Orlando in Florida (Telegraph 26 Feb 2010), but for killer whales at least the recent realisation of the fact that we have more than one species might also be a factor in reducing their popularity (New Scientist 02 May 2010). Apparently only one of the three species now recognised feeds on fish – so will people want to go to the zoo to see dolphins and seals being fed to the orcas?

Icelandic ash food for phytoplankton? Scientists are to study the recent volcanic ash fall from the Eyjafjallajökull volcano in Iceland to see if it has encouraged phytoplankton growth. A lot of people have said that we should look at artificially fertilizing the world’s oceans to try and increase carbon capture (greenhouse effect and all that), viewed in this light this work looks like a free experiment… From BBC News 27 April 2010

Environment driving speciation? An interesting essay in PLoS Biology on how environment and changes to the environment influence adaption or extinction events. The aim of the authors is to develop a predictive model for the effects of a climatic change on the species subjected to the change. There is quite a lot of interest in marine conservation circles about how recent bleaching of corals due to higher than normal summer temperatures might effect their long-term survival, whether or not the theory here might be applicable…
From Chevin L-M, Lande R, Mace GM (2010) Adaptation, Plasticity, and Extinction in a Changing Environment: Towards a Predictive Theory.
PLoS Biol 8(4): e1000357. doi:10.1371/journal.pbio.1000357
(See also our previous post on iron limiting productivity)

Seamounts – the latest frontier: Seamounts, mountains that rise from the seafloor, may rank as some of the most common ocean habitats in the world with more than 45,000 seamounts dotting the ocean floor worldwide. Latest research suggests that seamounts not only make up the largest area of ocean habitat, they are also highly productive environments that can serve as habitats for important commercial fish species like orange roughy and sablefish. (Authors note – it seems unlikely that seamounts make up more area than either abyssal plain or continental shelf, so perhaps I’ve mis-read this report). From Marine Conservation News, Monday, May 03, 2010.

As part of the current Marine ID course I’ve been running around trying to get together photos of some common seaweed for part 2… Unfortunately the local coastline is not at all hospitable to seaweed, the extensive mudflats of Morecambe bay are good for molluscs and worms, but offer few attachment points for the larger algal species (I think the phytoplankton might be a fascinating study – but that would be a bit outside the current remit!).

Never the less, I took my camera down to the beach at the weekend for the MCS walk from Warton Crag and round Jenny Browns Point by Silverdale (Saturday 24th April).

Here there is some hard ground, allowing seaweed to get a hold. Highest up the rocks appeared Blidingia (filamentous green stuff) and small amounts of Ulva intestinalis (fatter tubular green stuff), followed by Pelvetia canaliculata (channel wrack), at the base of the sequence was Fucus spriralis (spiral wrack) – beyond that stretched the mud as far as the eye can see…

The complete sequence was over in about 30cm of height – so extremely truncated!

Thanks to Hilary for organising the walk (my feet have almost forgiven me!)

The chlorophyl pigments have long been believed to be the basis for all autotrophy/phototrophy on earth, and these pigments therefore pretty much prop up the rest of the food chain (including yours truly). We know eukaryotic algae have a range of ‘helper pigments’ – this is why red algae are red, and not (usually!) green, but these transfer energy to the chlorophyl system, rather than drive metabolic pathways directly.

In 2000 a new group of membrane based proteins the proteorhodopsins were discovered in some cyanobacteria (blue green algae). These were shown to have the ability to drive a trans-membrane proton pump using only sunlight. Initially believed to have a sensory function, the latest work published in PLoS Biology indicates that the proton gradient created by the pump can drive the ADP-ATP conversion, and so be used as a general energy source for the cell. The long and the short of it is that cyanobacteria that have proteorhodopsin survive starvation in sunlight better than those that don’t, implying strongly that the proteorhodopsin generates real nutritional value for the bacterium.

This paper reinforces my prejudice that the prokaryotes are advanced organisms. These little guys might not have gone in for massive cellular machinery, but the chemistry they can do is really top notch!

Gómez-Consarnau L, Akram N, Lindell K, Pedersen A, Neutze R, et al. (2010) Proteorhodopsin Phototrophy Promotes Survival of Marine Bacteria during Starvation.
PLoS Biol 8(4): e1000358.doi:10.1371/journal.pbio.1000358

“Day 44: Still stranded with nothing but empty water as far as the eye can see”

More truth in this cartoon than a page of words. Enjoy! (View full size).

Each week I scan several thousand blog and news posts, picking out ones of interest to me and writing a bit about them – if I have time. Two problems – selfish interest, and lack of time! Here I’m going to try something a bit different, and be a lot less selective, but only write a very short tag for each item. This way hopefully you get a chance to find stuff of interest w/o having to scan everything…

Here goes my marine science roundup #1:

Plankton’s importance for carbon fixation: In the marine ecosystem both eukaryotes and cyanobacteria are important for fixing carbon at the base of the food chain. This article indicates that the eukaryotes (diatoms, dinoflagellates, protozoa and ‘seaweed’) are responsible for a bit under half the total carbon fixation in the world’s oceans (via ScienceDaily, Apr. 16, 2010).

Seabed Biodiversity in Oxygen Minimum Zones: Lack of oxygen in the water column favours some unusual organisms, and can increase biodiversity (as long as the areas are not too large). From ScienceDaily Apr. 19, 2010.

Smart fish adapt to environmental changes: Living in a changing or dynamic environment seems to favour smarter fish. From PLoS Biology 8(4): e1000351. doi:10.1371/journal.pbio.1000351.

Masses more bugs: The number of microbial species in the world’s oceans may be one hundred times greater than previously estimated. From Nature News, April 18, 2010.

New species of bacterium discovered: I guess given the increase in the number of microbes now expected, reporting each discovery individually might have to go by the wayside – so make the most of it! This one was found in the gut of a worm that lives in a Swedish fjord…

Junk food: A beached whale that died in Puget Sound (US) was found to have a pair of trousers, a golf ball, surgical gloves, small towels, and more than 20 plastic bags in its stomach. The problem with plastic litter is not confined to the US, the MCS organises beach litter surveys around the UK to monitor the state of our seas, and bring pressure to bear to get them cleaned up. You can help – see our diary pages for the next beach cleanup!

Fish oil supplements provide no benefit: The largest ever trial of fish oil supplements has found no evidence that they offer benefits for cognitive function in older people. The trial author noted that the duration of the trial might not have been long enough for any true beneficial effects to be detected amongst this test group of initially healthy older people. From ScienceDaily Apr. 21, 2010.

Big Seas, Big Trouble? An extended article about the effects of increased CO₂ on Ocean Acidification, and how that will effect life in the oceans in the coming decades. From Santa Barbara Independent Thursday, April 22, 2010

Carbon dioxide emissions causing ocean acidification: US congressional report finds that CO₂ emissions will have unknown effects on marine life (see also previous article). From ScienceDaily Apr. 22, 2010.

What are you eating? DNA analysis shows that a large proportion of the fish eaten in Dublin is mis-sold as something it isn’t. Similar results have been reported in the US, and the problem is likely to be global. From ScienceDaily Apr. 22, 2010.

More than one killer whale? recent DNA profiling data suggests that there is more than one species of killer whale.

We don’t usually try to ID bacteria, but this does not mean that they are unimportant. While each bacterium might be tiny, they can group together in enourmous numbers, and contribute a significant proportion of the biomass of any ecosystem. One recent discovery was a microbial mat lying on the sea floor off the coast of South America that covered an area the size of Greece!

The Census of Marine Life (previously blogged here) estimates that between 50 and 90% of the entire biomass of the marine system is in the form of microscopic organisms.

Our next Marine ID lecture on Wednesday 12 May the will look very briefly at some microscopic algae (phytoplankton), before turning to try and give pointers on how to identify some common (large and easily spotted) seaweeds!

More information:
Giant Undersea Microbial Mat (via Science Daily)
Census of Marine Life
MCS Diary – more lectures/meetings and events

Thanks to everyone for supporting this campaign, the Chagos islands have now been designated as a no-take marine reserve.

This declaration will make it the largest marine protected area in the world, totalling more than 210,000 square miles – an area twice the size of the UK. The combination of tropical islands, unspoiled coral reefs and adjacent oceanic abyss makes this area comparable in global importance to the Great Barrier Reef or Galapagos Islands.

More information about the Chagos islands project:

www.protectchagos.org

An octopus? We’re aware of the amazing art of mimicry cuttlefish have, blending into their backgrounds, but their close relative the octopus may go one better again, by pretending to be a fish! The Atlantic longarm octopus, a caribean species, has been filmed mimicing flounder and other bottom-dwelling flat-fish. It is not clear why they do this, but video is available on the National Geographic website. The story is also picked up byt the BBC World Service’s Science in Action. Links for more information:

National Geographic: Atlantic Octopus Mimics Flounders—A First

Science In Action: 12/03/2010 (Ivory trade…)

Thanks to Michelle Cooper of Lancaster Maritime Museum for a very beautifully illustrated talk on the river Lune through Lancaster (Wednesday 11th March 2010). Lots of views of activity on the river over the last 400 years, which got everyone in the audience judging how things have changed. The images used to illustrate the talk were from the Lancaster City Council collection. These will be on display at the Maritime Museum until the 11th April 2010. For more information:

Tales from the riverbank

The competition is part of the celebration of the silver anniversary of the Lancaster Maritime Museum. Photographs on the COAST theme – from shipwrecks to sandy beaches – are invited. The best entries will be displayed in the Exhibition Gallery.

For further details, including PRIZES, please see the entry form below:

Coast photo competition entry form. (300kB PDF)