A bit more science from the ocean floor – and, indeed, elsewhere in the water column, with this week’s roundup. The history of fishing is a popular topic, with work from the MCS on evaluating how much effort the fishing industry is having to put in to catch an ever diminishing resource, and with a new project to see how fish stocks have changed since medieval times…

Climate change will speed the spread of invasive fish to northern Europe: Spanish and French researchers have evaluated the spread of the invasive mosquitofish Gambusia holbrooki, which is native to the United States and lives in Mediterranean rivers in Spain and France. The species, which prefers warm waters, is abundant throughout all the countries in the Mediterranean basin, but has yet to become established in the United Kingdom, where the water is currently too cold. Gambusia spp. have caused the decline of many native fish and amphibian species worldwide. From ScienceDaily (Apr. 29, 2010)

Why are some farmed fish deformed?: Norwegian researchers have been uncovering some of the reasons for malformed farmed fish such as cod and salmon. It appears that fast currents in the tanks when the fish are young give rise to spinal injuries, and so deformed adult fish. From ScienceDaily (Apr. 30, 2010)

Fewer fish means the fleet works harder : Researchers from the University of York and the MCS used UK Government data on the amount of fish caught and the size and number of boats involved (an estimate of the fleet’s fishing power) to analyse the change in fish stocks since 1889. By this estimate the modern UK trawl fishing fleet has to work 17 times harder to catch the same amount of fish today as it did when most of its boats were powered by sail. The peak in fish landings occurred in 1937. From ScienceDaily (May 4, 2010)

Water ferns help design efficient ships: Superhydrophobic surfaces have been known for some time – these prevent water wetting a surface, and have the potential for reducing drag very dramatically. Unfortunately the effect is not very stable, with water breaking through the barrier after a few hours of use. A small water fern called salvinia molesta may show a way forward. This has finy hairs that are hydrophobic for part of their length – repelling water, but have hydrophilic tips. The effect of the tip is to pin water as the outside later in a sandwich, holding the trapped air between the plants skin and the water in place. It is claimed that surfaces based on this principle may reduce fuel usage by shipping by as much as 10%, equivalent to reducing the total global energy requirement by 1%.

A history of fishing: A new research project by scientists at Cambridge University is to analyse fish bones from archaeological settings to work out where the fish were caught. The intention is to piece together a history of the usage of fish stocks in Europe over the last 1000 years.

National Maritime Museum exhibition: Boats that Built Britain: In conjunction with BBC4 television series about maritime Britain. Exhibition starts 8th May 2010.

Ancient lead shields modern detector: Lead from a Roman shipwreck is to provide shielding for the neutrino experiment located under the Gran Sasso mountain in central Italy. The radio-isotope lead-210 that was originally in the ingots has almost completely decayed over 2000 years on the floor of the Mediterranean, making it an ideal material for protecting the new sensitive detector.

Oceanographers survey marine landslide: Researchers plan to create the first detailed maps of the submerged volcanic landslides around the Soufriere Hills volcano, Montserrat. Modern volcanic activity has been tame in comparison to what has happened over the last millenium, with landslides involving over five cubic kilometres of material that travelled underwater for tens of kilometres. Scientists are interested to learn how and why large volcanos of this type occasionally collapse into the sea. From ScienceDaily (May 5, 2010).
Location of Soufriere Hills volcano in Google maps

How does a shark smell? The way fish smell their environment is quite different to the way we do. We breath air through our nose, while a shark swims, and sweeps its head from side to side, to drive a constant current of scent bearing water around its nasal cavity. From ScienceDaily (May 5, 2010)

NASA explores inner space: NASA is to use the Aquarius Underwater Laboratory, Key Largo, to simulate activity on another planet. From Space.com, (4th May 2010)

Marine ecology special issue: This open issue of the journal Marine Ecology looks at how habitat heterogeneity is important in generating and maintaining biodiversity on continental margins. While the survey areas for the studies are deeper than we would be interested in diving(!), there are some interesting survey ideas – such as looking at numbers of species along transects and comparing this to bottom types – with which we are pretty familiar from the standard MCS seasearch form.

Countries ranked by environmental impact: A new study by the University of Adelaide’s Environmental Institute ranks countries by the damage they are doing to the environment. The indicators used were natural forest loss, habitat conversion, fisheries and other marine captures, fertiliser use, water pollution, carbon emissions from land use and species threat. From ScienceDaily (May 4, 2010)

Genetic diversity the key to coral survival: The symbiotic relationships between the algae and coral is central to the survival of the coral, with the algae providing the coral with energy, whilst the coral provides protection and nutrients to the algae. This relationship is, however, very sensitive to changes in temperature. In recent years high sea temperatures have lead to bleaching events, where the aglae have died. The susceptibility of the coral to these damaging, and potentially fatal, bleaching events is in part dependent upon the genetic diversity of the algal partners available to the coral. From ScienceDaily (May 7, 2010)