Ocean Acidification – The Ocean’s other problem with CO2

This guest post is from Elliot Scanes, a PhD candidate from Western Sydney University who runs cool experiments to understand the impact of climate change on our molluscs. Elliot has a great Instagram research account with Dr Vicky Cole called seao2, so give them a follow to keep up to date with their work.

Ocean Acidification – The Ocean’s other problem with CO2 

by Elliot Scanes

Humans are currently emitting CO2 faster than has occurred on Earth for millions of years. Currently, atmospheric CO2 concentrations are at their highest point in 800,000 years and don’t look like slowing any time soon. Inevitable global warming as a consequence of the excess CO2 and other pollutants causing the “greenhouse effect” is well established among scientists (despite what politicians might say). This warming of the earth will eventually also cause warming of the oceans, most notably affecting species ranges. But this is not the only way excess CO2 is going to change the world’s oceans. The oceans have already absorbed 40% of the CO2 emitted by humans, and will keep continuing to do so. As CO2 dissolves in seawater, it forms carbonic acid, which, in turn causes the oceans to acidify. So far, oceanic pH (the measure of acidity) has fallen 0.1 units, and is predicted to fall 0.3 – 0.4 pH units by 2100 unless drastic global action is taken to curb emissions.


Collecting Sydney rock oysters (Saccostrea glomerata) for experiments in Port Stephens.


Opening flat oysters (Ostrea angasai).









This small decrease in pH may seem insignificant, however pH is measured on a natural logarithmic scale (for those mathematicians) which means that each unit is an order of magnitude larger than the previous. A 0.3 unit drop in pH means that calcium carbonate, the mineral that all shelled animals shells are composed of, is now soluble in seawater. Predictably, scientists are most concerned about the shelled animals of the ocean like molluscs, crustaceans and cnidarian (corals). Investigations by our lab at Western Sydney University have shown that under these scenarios Sydney rock oysters will have difficulty forming their shell, especially in their juvenile stages. These difficulties waste vital energy, which is especially important in an environment where you always need an edge on your competitor. Similar studies have found comparable effects in sea urchins, corals, scallops and almost every shelled animal in the ocean that you can think of. Continue reading

Dragging the chain – does anchoring by large ships impact our marine life?

I’m excited to announce that I’ll be joining a multidisciplinary team of researchers, supported by UOW’s Global Challenges program, to investigate the potential impact of large ships anchoring on our marine life and seafloor habitats.

ship 2

As an island nation, we are heavily dependent on shipping, with large ships transporting 99% of our trade by volume. Prior to entering our ports these large vessels may anchor in deep water, often for many days, waiting for their turn to exchange cargo.

Now when I say ‘large’ I mean freakin huge (see pic below). These ships are between 200-300 metres long and to anchor they require an anchor chain up to 250 metres long where each individual chain link can weigh up to 200 kilograms! Continue reading

Australian science channels 2015 postgraduate survival guide out now.

post grad survival guide 2015 cover

The 2015 Postgraduate Survival Guide is now available through Australia’s science channel and Lachlan from Fish Thinkers talks fish tracking in the hot topics section Article here. There is a ‘photo’ link with quite a few of our tracking field work photos as well and some nice underwater photos from James Cook Uni in the marine conservation section. The guide is far from marine based though and covers numerous fields from robotics to astrophysics and is well worth a read if you are considering masters or PhD research down the track.

2015 guide hot topics

More down loads options including google play and Itunes can be found at http://riaus.org.au/postgraduate-survival-guide/

Designing a fish identification survey app for use underwater in the Caribbean

Lionfish in the Caribbean.  http://www.islamarexp.com/

Lionfish in the Caribbean. Copyright Duane J Sanabria http://www.islamarexp.com/

My fellow PhD candidates over in Puerto Rico, Chelsea & Evan Tuohy are undertaking a lot of interesting marine research. One of their current projects they are working on is developing a fish identification and surveying app for Caribbean reef fish ID and underwater surveys. Chelsea explains in more depth in her guest blog below.

I first started diving in 2008, and it was an undergraduate field course hosted at the University of Puerto Rico, Mayaguez’ Isla Magueyes field station that introduced me to the work of a field scientist. I lived in un-airconditioned dorms, woke up early to dive every morning, and spent the afternoons pouring over fish identification books. This was my first time trying to identify Caribbean reef fish, and I had zero background on this subject. Continue reading

The global tracking map: your key to discovering how the marine world moves.

VEMCO researchers map

VEMCOs researchers map: ‘Help us help you collaborate with the best researchers in the world and let us “Put You on the Map”! Red pins represent studies using VEMCO products, the dark pins represent institutes’.

For those that have an interest in animal movement in the oceans, I’d like to draw your attention to a handy and interesting tool on the VEMCO website; the global tracking map. This tool Continue reading

Special underwater video session – ASFB conference

I’m very excited to be co-convening a special session on the use of video technology to better understand fish ecology and behaviour at the Australian Society of Fish Biology conference 2015!! See flyer below for details. Registration and abstract submission ARE NOW OPEN!!

Also check out ASFB’s Facebook page here for regular updates.

ASFB custom

New underwater video up: extended BRUV highlights

Baited Remote Under Water Video (BRUV) Video highlights from some recent research we have been undertaking here at Fish Thinkers.<!–more–> We have been using this as background footage at a few events and after a few requests we decided to put it up online. Show it to your cat…they will love it ;).  Feel free to share or show people that might be interested. Whilst on that topic thanks to everyone who has shared our videos, photos and blog posts on social media, it is much appreciated (and rather surprising how many reads we have gotten on topics we least expected people to be interested in).

Of course all of this BRUV research wouldn’t be possible without the extensive support of the Dr Nathan Knott, the NSW Fisheries (DPI) and the University of Wollongong.