Report card on Australia’s oceans

I love being a scientist. It can be the most self-indulgent of careers and I feel lucky to live in a society that allows me the freedom to pursue ideas and information. I have the opportunity to explore ideas about how humans interact with our oceans, how we do bad things to them, and most importantly to me, try to figure out how to help them recover. The first step is gathering this information so that people can access it.

While scientists often disagree on things (a very important part of the job), getting a group of scientists together on a problem can truly help to pull together a massive amount of information very rapidly. In this spirit, the “Marine Climate Change Impacts and Adaptation Report Card (Australia)” was released last week. I am lucky enough to have been involved with two of the chapters, observed impacts of Ocean Acidification and observed impacts on marine Macroalgae. Unfortunately, I’d have to say that things aren’t looking good. We are only at the leading edge of some of the changes we are going to see over the next 100 years and some of the observed changes are already bad.

An example that most people wouldn’t know about (because you can’t see it from the surface) is the shift in the distribution of some algae. Algae, aren’t they just the “seaweeds” that we see washed up on the beach? Well, yes, but before they get to the beach they are the foundation of many food webs of the ocean; if they are lost then so are the ecosystems that they support. I must be honest here, when we started this project I didn’t actually expect to find anything to have happened yet, but it has. We have documented substantial southward shifts of entire assemblages of these algae on both the east and west coasts of Australia.Why? The waters of both coasts have warmed rapidly over the past 50 years. In fact, the Leeuwin Current was so strong this year with warming and El Nino that it pushed well into South Australia (see here for a Sea Surface Temperature image from IMOS). Not unheard of, but becoming stronger and more common.

Are we in danger of losing our iconic kelp forests? If so, what will happen to the ecosystems that they support (including 100’s of millions of dollars worth of fisheries)? Only time will tell, but I sincerely hope we can figure out a way to help them…..

The present…..

 

 

 

 

 

 

 

 

 

The future?

Super trawler, Super bad?

Over the past week there has been a lot of media attention thrown at the imminent arrival of a super trawler in Australian waters. It seems that there is strong objection from a lot of the population but objections are far from unanimous. So, what are the issues surrounding super trawlers? Well, it depends on your point of view:
1. Bycatch.

Bycatch, or non-target species caught in the nets, is an issue with trawlers – all trawlers. The size of the nets on super trawlers will mean that there is a large amount of bycatch (e.g. dolphins, turtles, sea birds) regardless of devices designed to limit bycatch being placed in the nets. This is sad and wasteful, but an issue with all trawling activities.

As an aside, I personally don’t believe that the use of the term “gently” with reference to these excluder devices
(“excluder device inside the net guides the animals gently up to an escape hatch on the top panel on the net” – see the article on ABC news for the full quote)

2. Jobs.

If I were the owner of a smaller trawler, I wouldn’t like to be sharing my fishery with this boat. Hundreds of fishermen around the world have been put out of business by big boats and collapsing fisheries……

3. Overfishing.

This is an interesting one. TECHNICALLY, if an effective quota system is in place on this fishery then the addition of this super trawler will not increase the likelihood of over fishing. However, I think this is the main issue in the debate. If you look at global fisheries, the vast majority are either fully or over exploited already. A lot are in an unarrested free-fall. Why? Because we’ve become way too good at catching fish. Our current level of technology means that if we don’t have accurate assessments of fish stocks, and believe me this is a supremely difficult task (so all credit to the people who have to figure it out), then we have the industrial power to over fish a stock before we even know it’s happening. In my mind, this is the real issue with such large boats.

But, this also brings me back to one of the issues I have with the way that society currently looks at problems. If you break something, or there is too little of what you want, don’t change what you’re doing just engineer a better way. With fishing that means bigger, more efficient boats. With climate change, it means geoengineering or carbon mitigation. But, why capture carbon dioxide through a chemical reaction and inject it deep into the ocean rather than switching to non-carbon based sources of fuel? At best you’re buying time to make appropriate changes, at worst you’re creating a false sense of security that will lead to disaster.

Are we risking the same choice with the super trawler?

Climate change real, says self proclaimed sceptic

At the end of July, the Berkeley Earth project team released the analysis of the most comprehensive land temperature data set ever collected. And do you know what they found? That climate change is real.

This is a stunning result because the leader of the team, Professor Richard Muller, has been a self-confessed “climate sceptic” for many years. In all fairness, Prof. Muller has always stated that his scepticism is based on what he perceives to be problems with the methods by which previous “climate” datasets have been analysed. So, after his team have analysed over 1.5 billion data points he is now (in his own words) a “converted sceptic”. What is more important, though, is that in his interviews he expresses the belief that not only were past analyses correct but that they have underestimated the rate of global warming. This is bad news.

But, to some of us this is no real surprise. In a recent paper, my collaborators and I used historical data to document a shift in entire assemblages of seaweeds due to warming ocean waters on both the west and east coasts of Australia. Not a good thing because thousands of species rely on these seaweeds for habitat and food.

Active Oceans Blog

Welcome to Active Oceans, a blog about just that!

I have set up this blog as a discussion forum for global activities concerning the world’s oceans. Why? Becuase the ocean forms the basis for all life on earth, yet we as humans seem determined to ruin it. So, in coming posts I will talk about my research about the ways in which we are damaging the ocean and how we can change the things we do to help keep our oceans active.

In the mean time, check out my home page for mor information about my research and publications!