Scientists map global routes of ship-bourne invasive species

byMatt McGrath | BBC News

Scientists have developed the first global model that analyses the routes taken by marine invasive species.

The researchers examined the movements of cargo ships around the world to identify the hot spots where these aquatic aliens might thrive.

Marine species are taken in with ballast water on freighters and wreak havoc in new locations, driving natives to extinction.

The research is published in the Journal Ecology Letters.

There has been a well-documented boom in global shipping over the past 20 years and this has led to growing numbers of species moving via ballast tanks, or by clinging to hulls.

Some ports such as San Francisco and Chesapeake Bay have reportedseveral exotic new species arriving every year. Economic estimates indicate that marine invaders can have huge impacts that last for decades.

Now, scientists from the UK and Germany have developed a model that might help curb these unwanted visitors. They obtained detailed logs from nearly three million voyages that took place in 2007 and 2008.

“Our model combines information such as shipping routes, ship sizes, temperatures and biogeography to come up with local forecasts of invasion probabilities,” said Prof Bernd Blasius from the University of Oldenburg.

While this is a mathematical model, the researchers were able to adjust it by carrying out field observations. They were able to estimate the probability that a species can survive a journey and establish a population in a subsequent port of call.

“It is called ecological roulette,” said Dr Michael Gastner from the University of Bristol.

“The probability of winning from the perspective of the invader is really tiny - but because the number of attempts are now growing with more and bigger ships, you play this roulette so often that you become a likely winner sooner or later,” he added.

The team says that the key hotspots for invasion are Singapore, Hong Kong, and the Panama and Suez canals. Cooler climates like the North Sea are less likely to be troubled, unless ships come from similar waters such as the east coast of the US. They conclude that very long trips are less likely to be a cause for concern.

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savephilippineseas:

Got that? ;-)

She shouldn’t sell seashells on the seashore. And neither should you! 

100 years of unprovoked shark attacks (1912-2013)

Andrew Barr and Richard Johnson | National Post

Surfer numbers have increased dramatically since the 1950s and advances in wetsuit technology mean people are going into the water all year round and staying out in the surf for longer periods, all of which increases the odds of someone being attacked by a shark. With this in mind, the National Post’s graphics team takes a look at the century in unprovoked shark attacks.

Blue = Male survivor

Pink = Female survivor

Black = Fatality

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Looks pretty colourful to me. 

Read more here including a break down of activities during the attacks and a close up of injury location (if any). 

This is a great visual back up for this (Attn: NERDS: Free journal article). Remember when I posted about  a new paper seeking to reclassify human-shark interactions? No? That’s ok. Here’s a snippet from the abstract:

There are few phrases in the Western world that evoke as much emotion or as powerful an image as the words “shark” and “attack.” However, not all “shark attacks” are created equal. Under current labels, listings of shark attack may even include instances where there is no physical contact between shark and human. The dominant perception of intent-laden shark “attacks” with fatal outcomes is outdated as a generic term and misleading to the public. We propose new descriptive labels based on the different outcomes associated with human–shark interactions, including sightings, encounters, bites, and the rare cases of fatal bites. We argue two central points: first, that a review of the scientific literature shows that humans are “not on the menu” as typical shark prey. Second, we argue that the adoption of a more prescriptive code of reporting by scientists, the media, and policy makers will serve the public interest by clarifying the true risk posed by sharks and informing better policy making.

rhamphotheca:

A cool new way climate change is killing bivalves

By Susie Cagle

We already know that carbon-dioxide-filled, acidic ocean water is no-good, very-bad news for mussels and other underwater shelled creatures, causing their shells to dissolve. But, as these things so often go, it turns out that climate change is even worse for bivalves than we thought: It’s unleashing an awkward kind of anti-puberty on them. They’re growing smaller and weaker, and now we find out that they’re basically losing their hair.

New research published in the journal Nature shows that mussels’ proteinaceuous byssal threads — the little stringy bits that allow them to stick their bodies on stuff — are particularly susceptible to ocean acidification. The researchers found mussels’ little stringy bits were 40 percent weaker when exposed to elevated CO2 levels, even when their shell strength and tissue growth weren’t affected…

(read more: Grist.org)                       (photo: Sapphire/Flutterby)

sexyactionplanet:

Dr Kathy Townsend from Turtles in Trouble with the debris extracted from a coastal sub-adult flat back turtle in Moreton Bay, Australia. Much of this was plastic bag remnants.