Freshwater Matters from the FBA April 2013

1. April 2013
Freshwater Matters
Freshwater Matters is a monthly electronic bulletin of the most recent
freshwater news from around the world, compiled by the Freshwater Biological
Association (FBA). It includes updates of what is happening at the FBA and ways
to get involved.
Contents
What’s happening at the FBA?
This month’s articles
Dolly Varden guts quadruple during yearly gorging session
Mouth-breeding frog is coming back from extinction
Study of dragonfly prey detection wins PNAS Cozzarelli Prize
Disease threatens aquaculture in developing world
Eel mystery deepens with shark chow-down
Antarctic Lake Vostok yields ‘new bacterial life’
Risk management in fish: How cichlids prevent their young from being eaten
Ladders to help voles get out more
New products to speed up lake recovery examined
Australia’s native frogs beat invasive toads
What’s happening at the FBA?
New job at the FBA - GIS Web-Developer (KTP Associate)
The FBA and University of Cumbria are offering an exciting opportunity for a
graduate or post-graduate wanting to develop skills and experience by working on
an innovative GIS web-development project. For more information please see the
FBAs job page at https://www.fba.org.uk/jobs-notices.
This month’s articles
Dolly Varden guts quadruple during yearly gorging session
Research published this month in the Journal of Animal Ecology shows that the
Dolly Varden, (Salvelinus malma) can expand its gut to four times its usual size
to take advantage of the feast provided by the eggs of spawning salmon. What is
interesting is that this increased capacity is not a result of stretching, but rather
the fish lays down extra tissue to increase the size of their digestive tract.
http://www.scienceworldreport.com/articles/5709/20130321/dolly-varden-trout-
guts-quadruple-during-yearly-gorging-session.htm
Mouth-brooding frog is coming back from extinction
Habitat destruction drove the Australian gastric-brooding frog to extinction in
1983. But using advanced cloning techniques researchers from the University of
New South Wales have demonstrated that it may be possible to bring them back.
The research was presented at a conference this month held in Washington that
discussed the science of “de-extinction”.
http://www.newscientist.com/blogs/shortsharpscience/2013/03/mouth-breeding-
frog.html
Study of dragonfly prey detection wins PNAS Cozzarelli Prize
A study on the physiology of hunting in dragonflies has won the Cozzarelli Prize
for “scientific excellence and originality” awarded by the editorial board of the
Proceedings of the National Academy of Sciences (PNAS). The study examined
how dragonflies are able to intercept their prey with 95% efficiency. The authors
examined a set of motor neurons linked to wing muscle that can detect movement
of prey through 360 degrees.
http://www.eurekalert.org/pub_releases/2013-03/mbl-sod031813.php
Disease threatens aquaculture in developing world
Aquaculture is the fastest growing food sector in the world according to the UN
Food and Agriculture Organisation. However, an analysis published this month in
the Journal of Applied Ecology indicates that disease may threaten the ability of

2. aquaculture to meet growing demands, just as wild fish stocks decline and climate
change threatens food production from other sources.
http://www.enn.com/sustainability/article/45726
Eel mystery deepens with shark chow-down
Efforts to track the migration root of the American eel (Anguilla rostrata) met
an untimely end when 6 of the 8 individuals being tracked by satellite where
eaten by Porbeagle sharks (Lamna nasus). However, the results have important
implications for efforts to conserve eels whose numbers have significantly declined
in recent years. There is now a need to build up a more detailed understanding of
the importance of predation in order to design effective conservation strategies.
http://news.yahoo.com/eel-mystery-deepens-shark-chow-down-160610427.html
Antarctic Lake Vostok yields ‘new bacterial life’
Russian scientists think that they have discovered a new type of bacteria after
drilling 4km through the ice to retrieve a sample of water from Lake Vostok. The
lake is the largest sub-glacial lake in Antarctica and estimated to have been cut
off from the outside world for around 15 million years.
http://www.bbc.co.uk/news/science-environment-21709225
Risk management in fish: How cichlids prevent their young from being
eaten
A species of cichlid in Lake Tanganyika may increase the chance of their offspring
surviving by putting them out for “adoption” by other parents, according to
genetic tests carried out on over 350 parents. The strategy ensures that should
the parents lose their nest to predation at least some of their offspring are likely
to survive.
http://www.eurekalert.org/pub_releases/2013-03/uovm-rmi031913.php
Ladders to help voles get out more
Isolated water vole populations in London are being provided with mini ladders
to help them cross the high, vertical edges of the Grand Union Canal and access
new territories. As numbers of water voles across the country have declined
the remaining populations have become more fragmented. It is hoped that the
scheme will encourage mixing and improve genetic diversity.
http://www.bbc.co.uk/nature/21804627
New products to speed up lake recovery examined
A study published in the journal Science of the Total Environment examines how
new materials can speed up the recovery of lakes impacted by eutrophication.
The recovery of such lakes often takes decades due to ‘legacy’ phosphorous in the
lake bed sediments. However, a range of products now offer the potential to short-
circuit the natural phosphorous cycle and speed up recovery.
http://www.ceh.ac.uk/sci_programmes/water/lake-recovery-products-examined-
news_2013_15.html
Australia’s native frogs beat invasive toads
A study published in Austral Ecology suggests that the tadpoles of the native
green tree frog can out-compete those of cane toads reducing their survival.
Experts are now suggesting that introducing green tree frogs into suburban areas
could represent one strategy to combat the invasive.
http://www.bbc.co.uk/nature/21629255
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interested!