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Best of 2013: OSEARCH presents a new kind of science… Duuun dun duuun dun…

By Ali (guest blogger)

Science is awesome. Sharks are awesome. And, when you combine the two, you get this!

shark1

I’ve been following this research group called OSEARCH for a while now and they do some pretty wild things. Including tagging and releasing Great White Sharks or White Pointers like Amy (pictured above). See OSEARCH’s Global shark tracker here or follow on facebook. There are a lot of unexplained mysteries when it comes to white pointers. shark2Until recently, very little was known about migratory patterns, where and when they breed, and their general behavior. OSEARCH has provided the means for marine scientist to go beyond traditional methods of obtaining data on apex predators. Through direct on-deck observations, as well as tagging and satellite tracking systems, our understanding of the biology and behavior of these sharks has skyrocketed. Check out this great news broadcast that describes OSEARCH’s work.

shark3A paper released this year (Domeir and Nasby-Lucas 2013) has investigated the migratory patterns of 4 adult female white pointers (using the satellite tagging programs made possible by OSEARCH) and found distinct seasonal migration patterns for northeastern Pacific white sharks. Their findings show these female sharks have a 2-year long migration course, compared to the male’s 1-year migration. It is speculated that female gestation lasts for about 18 months and they spend much of this time offshore. Interestingly, the preferred prey for these pregnant females is unknown, although both male and female migratory paths shark4overlap with three species of spawning squid and sperm whales, but no small marine mammals, suggesting unique feeding regimens (see here Mega Shark vs Giant Octopus, for Hollywood dramatization).

On top of what little we actually know about these astounding creatures, shark populations are declining in many parts of the world, with 30% of species threatened or near-threatened with extinction. It is difficult to build conservation and management strategies when so little is known about the sharks themselves or what is causing their decline in numbers. OSEARCH’s groundbreaking research will help scientists to discover more about these beautiful creatures and will help to protect one of the planets most revered apex predators.

shark5

Documentary: Acid Ocean

Site exposed to very high concentrations of CO2 where coral developement ceases to exist. Credit: Katharina Fabricius
Site exposed to very high concentrations of CO2 where coral developement ceases to exist. Credit: Katharina Fabricius

By Claire

If you’re looking for a bit of mental stimulation tonight, there is a documentary airing on SBS at 7:30pm that may be of interest.

The doco is titled, “Acid Ocean” and explores the acidifying ocean, caused by increased CO2 levels in the atmosphere.

“Marine scientists across the world are racing to tackle the most urgent environmental challenge facing our planet today – ocean acidification. From the icy polar seas to the world’s most pristine coral reefs we track the latest scientific research. Heading the investigation is Dr Katharina Fabricius from the Australian Institute of Marine Science. She’s made a game-changing discovery. Nestled amongst Papua New Guinea’s stunning coral gardens is a unique reef – a window to the future of our oceans.”

Check out a sneak peak:

If you do miss it tonight, you can watch the program online on SBS On Demand, after it has gone to air (if you are in Australia).

The Great Barrier Reef faces destruction

reefBy Bianca (guest blogger)

Australia’s new prime minister has given the green light for mining companies to destroy Australia’s natural wonder and UNESCO World Heritage site, the Great Barrier Reef.

The Great Barrier Reef stretches over 2300 km along the coast of Queensland and is home to around a quarter of all species that can be found in the world’s oceans. Listed as a UNESCO World Heritage site in 1981 the reef recently faces one of its hardest battles: a changing climate.

Sediment and algal overgrowth have overtaken this once-healthy reef. (Courtesy Emre Turak/Australian Institute of Marine Science)
Sediment and algal overgrowth have overtaken this once-healthy reef. (Courtesy Emre Turak/Australian Institute of Marine Science)

Rising ocean acidity due to high atmospheric carbon dioxide levels and increasing water temperatures damages the corals; floods and storms flush mud, pesticides and fertilizers from farmland into the ocean and mining companies pollute the reef by dumping silt into the ocean and letting their freighters pass through. Continue reading “The Great Barrier Reef faces destruction”

Where does all the plastic come from?

One of the many many "ghost nets" floating around the ocean. They are abandoned fishing nets, which continue to catch and trap fish and other marine life. We don't know how long these take to break down.
One of the many many “ghost nets” floating around the ocean. They are abandoned fishing nets, which continue to catch and trap fish and other marine life. We don’t know how long these take to break down.

By Claire

We’ve posted a couple of times about the giant garbage patches sitting in the middle of the world’s oceans, but I want to re-visit this topic again today.

Earlier this week, I attended a really great seminar, given by Erik van Sebille, from UNSW, titled, “Pathways of Marine Plastic into the Garbage Patches”.

Erik is a physical oceanographer, and so came to the issue of the ocean’s garbage patches from a different direction, “where does all the plastic come from?” Continue reading “Where does all the plastic come from?”

OSEARCH presents a new kind of science… Duuun dun duuun dun…

By Ali (guest blogger)

Science is awesome. Sharks are awesome. And, when you combine the two, you get this!

shark1

I’ve been following this research group called OSEARCH for a while now and they do some pretty wild things. Including tagging and releasing Great White Sharks or White Pointers like Amy (pictured above). See OSEARCH’s Global shark tracker here or follow on facebook. There are a lot of unexplained mysteries when it comes to white pointers. shark2Until recently, very little was known about migratory patterns, where and when they breed, and their general behavior. OSEARCH has provided the means for marine scientist to go beyond traditional methods of obtaining data on apex predators. Through direct on-deck observations, as well as tagging and satellite tracking systems, our understanding of the biology and behavior of these sharks has skyrocketed. Check out this great news broadcast that describes OSEARCH’s work.

shark3A paper released this year (Domeir and Nasby-Lucas 2013) has investigated the migratory patterns of 4 adult female white pointers (using the satellite tagging programs made possible by OSEARCH) and found distinct seasonal migration patterns for northeastern Pacific white sharks. Their findings show these female sharks have a 2-year long migration course, compared to the male’s 1-year migration. It is speculated that female gestation lasts for about 18 months and they spend much of this time offshore. Interestingly, the preferred prey for these pregnant females is unknown, although both male and female migratory paths shark4overlap with three species of spawning squid and sperm whales, but no small marine mammals, suggesting unique feeding regimens (see here Mega Shark vs Giant Octopus, for Hollywood dramatization).

On top of what little we actually know about these astounding creatures, shark populations are declining in many parts of the world, with 30% of species threatened or near-threatened with extinction. It is difficult to build conservation and management strategies when so little is known about the sharks themselves or what is causing their decline in numbers. OSEARCH’s groundbreaking research will help scientists to discover more about these beautiful creatures and will help to protect one of the planets most revered apex predators.

shark5

Investigating the Investigator

By Kelly

investigator_19-02-13_0018-banner-e1365372338896
Source: http://csirofrvblog.com

One of the major draw cards for the Earth Sciences comes from the tantalizing prospect of field work. And for marine scientists, this couldn’t be more exciting than when field work involves a trip on a research vessel; an excursion we affectionately call going on a “cruise”*. I have not had the pleasure of sailing onboard Australia’s RV Southern Surveyor and opportunity is fading fast with the Research Vessel’s imminent decommissioning.

Instead, the Australian marine science community will set forth into our watery future aboard the RV Investigator, which in similar fashion to its namesake will be able to circumnavigate our great continent, survive battering by fierce storms and  potentially be required to serve for ~70 years. But it’s not the capabilities that the two Investigators share that have the oceanographers amongst us all aquiver, but the technological modifications that ???????????????????????????????distinguish them. Not least the fact it has its very own blog, there is also talk of winged keels, dual polarisation weather radar and ‘work’ boats straight from the set of Baywatch (okay so they are orange, other than that they have nothing in common with Baywatch).
Continue reading “Investigating the Investigator”

Deepest Undersea Vents Discovered

Black Smoker in the Cayman Trough (http://www.thesearethevoyages.net/jc44/images/smoker4.jpg)
Black Smoker in the Cayman Trough (http://www.thesearethevoyages.net/jc44/images/smoker4.jpg)

by Brendan

Last night I came across a BBC article showing that a team of UK scientists have discovered a field off hydrothermal vents almost 5 km below the ocean surface in the Cayman Trough, part of the Caribbean Sea.

 

These hydrothermal vents (often known as Black Smokers) are formed on the sea floor near plate boundaries where superheated water escapes from fissures in the Earth’s surfaces. Continue reading “Deepest Undersea Vents Discovered”

When jellyfish attack, or atleast swarm

091116-jelly-fish-hmed-120a.grid-6x2
Source: http://www.nbcnews.com/id/33959849/

By Kelly

Along with the Great Pacific Garbage Patch if you are a marine conservationist you have undoubtably heard of the alarming rate with which enormous swarms of jellyfish are threatening to take over a oceans. A consequence of climate change? Evidence that our oceans are becoming wastelands, fit for no other life than that of the gelatinous? Or worse…an urban myth?

A recent article in the Proceedings of the National Academy of Sciences (or PNAS, pronounced PeeNAS) highlighted that this notion is based on a few scattered reports rather than a thorough synthesis of jellyfish population metrics. Using data ranging from 1790 to 2011 Condon et al claim that while a strong 20-year oscillation is apparent, there is yet sufficient proof that a significant upward trend in jellyfish populations has occurred.  Continue reading “When jellyfish attack, or atleast swarm”

From the archives: The debate over calcium carbonate


A rather terrible limerick by Kelly (originally posted 16th April 2012)

There once was a rather heated debate,

over the formation of calcium carbonate.

Was the biology to blame?

Or the scientists wrong to claim?

That climate is buried in coral precipitate.

For those who don’t work with the ocean’s carbonate system, or with calcium carbonate bearing organisms, one of the longest standing and most heated debates revolves around how these organisms actually secrete their skeletons. Scientists just can’t agree on the molecular mechanism behind the precipitation of biogenic calcium carbonate, or calcification as it is commonly known. Is there active transcellular transport of specific cations (i.e calcium), or are the necessary cations obtained through direct seawater transport? And can the internal pH of this calcifying fluid be biologically controlled to favour precipitation?

While this might not sound like cause for contention, there is a lot riding on the outcomes of this research (and has been an element of pugilism along the road to discovery) . Many important archives that we rely on for climate reconstructions  come out of biogenic carbonates; think corals, both surface and deep-sea,and foraminifera. These organisms are ubiquitous in the fossil record and the way we interpret the chemical composition of calcium carbonate relies on our understanding of how it formed in the first place. From these archives our climate reconstructions and modelled scenarios inform policies that ultimately dictate how we will respond to current climate change. And then of course there is ocean acidification (cue dramatic music). Will the great reefs of the world survive the current drop in ocean pH?   Am I giving this whole calcification argument enough weight yet?

There has recently been a flurry of activity in the scientific literature, with some heavy hitters all stepping into the ring. Unfortunately, not all of these articles are freely accessible but I shall give you the run down on, and links to, the current bout in the calcification prize-fight. Continue reading “From the archives: The debate over calcium carbonate”

From the archives: Data visualization, super trawlers and ocean circulation

By Kelly (originally posted 21st September 2012)

I’ve a couple of things I’d like to cover today that are all related by a common thread: ocean circulation (again). Last week I wrote about the Great Pacific Garbage Patches that describes the refuse that rides the tides until it is bounded by large circulation features in the eastern and western Pacific, aswell as in a newly discovered ‘patch’ of the North Atlantic (thank you Susan). I was prompted to write this post after reading about the Japanese tsnumai debris crossing the Pacific, and collecting on the shores of western Canada (thank you Evan). Well today I’d like to touch on something a little more controversial that also relates to circulation; why propose ‘super-trawling’ off the southeast Australian coastline?

http://www.oceanclimatechange.org.au

The action of the world’s current systems couldn’t be more beautifully displayed than in this spectacular animation (above) that recently came my way (thank you NASA, courtesy of thank you Bec). And, like yesterdays post (thank you Nick), it is another demonstration of data-visualization at its finest. If I can draw your attention to around 2:10 you will see a series of whirling dervishes, other wise known as eddies, that spin-off the south-east Australian coast, extending beyond the Tasman Front, which is seen as a jet of water that breaks from the coast near Sydney and meanders off toward New Zealand. The eddies (or dervishes) that continue southward toward Tasmania are of interest today. I present to you the East Australian Current Extension: how PhD students and super-trawlers alike, learned to love ocean circulation.

Continue reading “From the archives: Data visualization, super trawlers and ocean circulation”

From the archives: The Kermadec Arc Explained

Black Smoker vent in the Atlantic (Source: http://www.eoearth.org/article/SS_Gairsoppa_recovery)

by Brendan (originally posted 17th May 2012)

Earlier this week, Mike and myself wrote about a period of dramatic growth of the Molowai submarine volcano, part of the Kermadec arc to the north of New Zealand. This morning I came across a good video from 3NewsNZ that describes the Kermadec arc/trench environment and includes many of the features that make science videos cool, including black smokers, false colour bathymetry, strange marine life forms and  even sharks.

You can find the video here – http://www.youtube.com/watch?v=IzvhPtxP37w

And for the cnidaria lovers out there

By Kelly

I know I’m not the only lover of Cnidaria out there. And if you are not already enamoured by animals with specialised stinging cells to capture their prey then you will be after this. I watched this on another fabulous blog: Science-Based Life and felt I had to share. More mesmerizing than a lava lamp, and that is saying something.

Cnidarian Lifeforms from Delrious on Vimeo.

A new discipline: Rogue geo-engineering

By Kelly

Example of phytoplankton bloom Source: http://io9.com/5952101/a-massive-and-illegal-geoengineering-project-has-been-detected-off-canadas-west-coast

Back in July, an American businessman illegally dumped 100-tonnes of iron sulphate into the ocean just west of Canada, reports the Guardian this week. Russ George allegedly gained permission from a First Nation’s community that border these waters after saying that iron fertilisation would not only sequester carbon, but that the act would replenish dwindling salmon stocks thereby benefitting the environment and local livelihoods. What is being dubbed as ‘rogue’ geoengineering, the act is in blatant violation of both the United Nations Convention on Biodiversity as well as the London Convention on dumping waste at sea. Both prohibit iron fertilisation for commercial gain, with permission for such projects only ever granted for legitimate scientific research. And legitimate research to date does not endorse iron fertilisation as a sustainable climate change mitigation strategy, with large uncertainties surrounding sequestration efficiency and flow on effects to marine ecosystems. From the Guardian:

“It is difficult if not impossible to detect and describe important effects that we know might occur months or years later,” said John Cullen , an oceanographer at Dalhousie University. “Some possible effects, such as deep-water oxygen depletion and alteration of distant food webs, should rule out ocean manipulation. History is full of examples of ecological manipulations that backfired.”

Continue reading “A new discipline: Rogue geo-engineering”

Why Coccoliths are voting for Obama: geology and politics

By Nick

A sphere of coccoliths under a scanning electron microscope. Created by the coccolithophore Emiliania huxleyi. Image from the Encyclopedia of Life.

Coccolithophores are tiny single celled planktonic organisms that live in the oceans. They have tiny armoured calcium carbonate plates known as coccoliths. Whilst still present and abundant today, during the time of the dinosaurs there were trillions upon trillions of these organisms living in the warm shallow oceans that pervaded much of the planet. Coccolithophore elections during the Cretaceous were hotly contested. And these notoriously liberal voting critters are still influencing voting patterns today.

Its just a pity they aren’t registered to vote, otherwise the trillions of coccoliths could easily swing an election. However they are doing their bit, through a curious bit of geology, and history, that leads to a swath of blue voting counties across the deep south of America. I came across this gem of a blog post via a couple of American geologist friends, it’s well worth a full read here, but here’s a summary.

A swath of blur voting counties stretch across the American South. Image from NPR, credited to Matt Stiles

Continue reading “Why Coccoliths are voting for Obama: geology and politics”

Not since the invention of photosynthesis

Dog also amazed by discovery of N2 fixing symbiont
(http://www.facebook.com/GreenUp.UNEP)

By Kelly

While I may be having a few weeks of epic failure, across the globe there are scientists documenting and publishing their epic success. Not since evolution invented photosynthesis* (or more specifically phytoplankton engulfed cyanobacteria and formed chloroplasts) has there been such a beautiful tale of symbiosis. Last week a report in Science described a newly discovered and unusual symbiotic relationship that occurs in the ocean. And the article, in a similar fashion to the dog pictured above, literally blew my hair back.

There are a number of things that make this discovery noteworthy. First of all I should like to point out that nitrogen fixation is equal in importance to carbon fixation, as both elements are required to form organic matter. Indeed, in vast tracts of the ocean the amount of primary productivity that occurs is set by the amount of available fixed nitrogen, which in turn sets the biological component of CO2 drawn down. But nitrogen fixation is a tricky business as it is very sensitive to oxygen and requires lots of energy. In the terrestrial biosphere you may have heard of rotating legumes through your pasture  to fertilize the soil (for all the farmers out there). Well it is the symbiotic bacteria that live in the nodules of the legume’s roots system that do the job, rather than the legumes themselves. And out there in the ocean, Thompson and co authors have just figured out a similar relationship, between a marine microbe (cyanobacteria) and host phytoplankton.

Continue reading “Not since the invention of photosynthesis”

Data visualization, super trawlers and ocean circulation

By Kelly

I’ve a couple of things I’d like to cover today that are all related by a common thread: ocean circulation (again). Last week I wrote about the Great Pacific Garbage Patches that describes the refuse that rides the tides until it is bounded by large circulation features in the eastern and western Pacific, aswell as in a newly discovered ‘patch’ of the North Atlantic (thank you Susan). I was prompted to write this post after reading about the Japanese tsnumai debris crossing the Pacific, and collecting on the shores of western Canada (thank you Evan). Well today I’d like to touch on something a little more controversial that also relates to circulation; why propose ‘super-trawling’ off the southeast Australian coastline?

http://www.oceanclimatechange.org.au

The action of the world’s current systems couldn’t be more beautifully displayed than in this spectacular animation (above) that recently came my way (thank you NASA, courtesy of thank you Bec). And, like yesterdays post (thank you Nick), it is another demonstration of data-visualization at its finest. If I can draw your attention to around 2:10 you will see a series of whirling dervishes, other wise known as eddies, that spin-off the south-east Australian coast, extending beyond the Tasman Front, which is seen as a jet of water that breaks from the coast near Sydney and meanders off toward New Zealand. The eddies (or dervishes) that continue southward toward Tasmania are of interest today. I present to you the East Australian Current Extension: how PhD students and super-trawlers alike, learned to love ocean circulation.

Continue reading “Data visualization, super trawlers and ocean circulation”

NSW State Government ignores sea level predictions

Erosion at Collaroy

By Claire

Legislation put in place by the former Labor Government of NSW stating that councils must take UN projections of sea level rise into consideration in their coastal management policies, has been overturned by the O’Farrell Liberal Government.

These laws were used to determine which coastal properties were ‘at risk’ of coastal erosion and to limit the future development of these ‘at risk’ areas. These laws compelled coastal councils to prepare for a forecast sea-level rise of 40cm by 2050 and 90cm by the turn of the century.

As a result, the value of coastal properties that had been identified as at risk dropped (by approx. 40%), prompting these people to petition government to review and ultimately remove the planning restrictions placed on them.

While I can sympathise with the people who own these coastal properties, the removal of these planning restrictions leaves the council open for future legal action. Continue reading “NSW State Government ignores sea level predictions”

Consequences of consumerism – “The Great Pacific Garbage Patch”

By Claire

Photograph by Chris Jordan

Regular readers of our blog might be starting to notice a theme developing over the last few days. It started with Evan posting about the debris from the recent Japanese tsunami, which is currently crossing the Pacific, which lead Kelly to tell us about the “Great Pacific Garbage Patch“.

These posts jogged my memory, reminding me of a series of photographic artworks by Chris Jordan, titled “Midway – Message from the Gyre“.

“On Midway Atoll, a remote cluster of islands more than 2000 miles from the nearest continent, the detritus of our mass consumption surfaces in an astonishing place: inside the stomachs of thousands of dead baby albatrosses. The nesting chicks are fed lethal quantities of plastic by their parents, who mistake the floating trash for food as they forage over the vast polluted Pacific Ocean.”

I encourage you all to take a few minutes and scroll through his gallery. The images are quite confronting.

Chris Jordon is in the process of putting together a movie about the Midway Albatrosses. The trailer is available to view online. (Be warned, it is very confronting). If you’re interested in following the film’s progress, the film website can be found here.

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