Limited nursery replenishment in coral reefs

27 03 2017
Haemulon sciurus

blue-striped grunt (Haemulon sciurus)

Coral reef fishes are wonderfully diverse in size, form, and function, as well as their need for different habitats throughout the life cycle. Some species spend all of their life in the same kind of coral habitat, while others need different places to breed and feed.

Fishes requiring different habitats as they progress through life often have what we call ‘nurseries’ in which adults lay eggs and the subsequent juveniles remain, and these places are often dominated by mangroves or seagrasses (i.e., they are not part of the coral reef).

While we’ve known for quite some time that when these nursery habitats are not around, adjacent coral reefs have few, if any, of these nursery-dependent species. What we haven’t known until now is just how far the influence of nurseries extends along a coral reef.

In other words, if a nursery is present, just how many new recruits do different areas of a reef receive from it? Read the rest of this entry »





Most-Bestest Environment Minister in the World, Ever

4 04 2016
Our Most-Bestest Minister Ever

Our Most-Bestest Minister Ever (i.e., the bloke on the left; interestingly, the bloke on the right leads one of the few countries in the world with a higher per capita emissions rate than Australia)

Australia has an appalling environmental record — hell, I have even written an entire book on our sorry state of environmental affairs. Of course, environmental damage is a slow accumulation of bad political decisions, neglect, corruption, greed and society’s general I-couldn’t-give-a-shit attitude, but the record of our recent government demonstrates not just classic political buffoonery and neglect, but an outright attack on the environment.

So it was impossible to restrain a disgusted guffaw when, in February this year, our ‘Environment’ Minister won the coveted ‘Best Minister’ in the World award at the World Government Summit in Dubai by Sheikh Mohammed Bin Rashid Al Maktoum, Vice President and Prime Minister of the United Arab Emirates and Ruler of Dubai.

Deserved ridicule aside, I was asked recently by The Conversation to contribute to a special report examining the profile performance of cabinet and shadow cabinet ministers, which is not only a responsibility I take seriously, but an honour to be able to provide a serious and objective appraisal of our Most-Bestest Minister Ever. My contribution dealt specifically with the environmental portfolio, so I appraised both the sitting Minister and the Shadow Minister. Judge for yourself based on their performances. Read the rest of this entry »





Disadvantages of marine protected areas

29 02 2016

 

 

 

Stop wasting time

Stop wasting time





It’s not always best to be the big fish

3 02 2016

obrien_fish_2Loosely following the theme of last week’s post, it’s now fairly well established that humans tend to pick on the big species first.

From fewer big trees, declines of big carnivores, elephant & rhino poaching, to fishing down the web, big species tend to cop it hardest when it comes to human-caused ecological disturbance.

While there are a lot of different combinations of traits that make some species more vulnerable to extinction than others (see examples for legumes, amphibians, sharks & teleosts, and mammals), one of the main ones is species size.

Generally speaking, larger species tend to produce fewer offspring and breed later in life than smaller species. This means that despite larger species tending to live longer than their smaller counterparts, their ‘slow’ reproductive output means that they are generally more susceptible to rapid environmental change (mainly via human intervention). In other words, their capacity for self-replacement is often too low to counteract the offtake from direct exploitation or habitat loss.

Despite a reasonable scientific understanding of this extinction-risk principle, the degree to which human disturbance affects species’ distributions is much less well quantified, and this is especially true for marine species.

I’m proud to announce another fascinating paper led by my postdoc, Camille Mellin, that has just come out online in Nature CommunicationsHumans and seasonal climate variability threaten large-bodied coral reef fish with small ranges.

With the world’s largest combined dataset of coral reef fish surveys for the entire Indo-Pacific (including the coral reef fish biodiversity hotspot — the Coral Triangle), we examined which conditions best described the distribution of fishes over a range of body sizes. Read the rest of this entry »





South Australia’s tattered environmental remains

16 04 2014
State budget percentage expenditures for health, education and environment

South Australia State budget percentage expenditures for health, education and environment

Yesterday I gave the second keynote address at the South Australia Natural Resource Management (NRM) Science Conference at the University of Adelaide (see also a brief synopsis of Day 1 here). Unfortunately, I’m missing today’s talks because of an acute case of man cold, but at least I can stay at home and work while sipping cups of hot tea.

Many people came up afterwards and congratulated me for “being brave enough to tell the truth”, which both encouraged and distressed me – I am encouraged by the positive feedback, but distressed by the lack of action on the part of our natural resource management leaders.

The simple truth is that South Australia’s biodiversity and ecosystems are in shambles, yet few seem to appreciate this.

So for the benefit of those who couldn’t attend, I’ve uploaded the podcast of my slideshow for general viewing here. I’ve also highlighted some key points from the talk below: Read the rest of this entry »





Australia’s (latest) war on the environment

3 03 2014

monkYes, the signs were there, but they weren’t clandestine messages written in the stars or in the chaos of tea-leaf dregs. We saw this one coming, but Australians chose to ignore the warning signs and opt for the American political model of extremism, religiosity, plutocracy and science denial.

Enter the ‘Tea Party’ of Australia – the ‘new’ Coalition where reigning Rex perditor Prime Minister Tony The Monk Abbott1 has, in just a few short months, turned back the clock on Australian environmental protection some 40 years.

Yes, we saw it coming, but it wasn’t a tautological fait accompli just because it concerned a ‘conservative’ government. It’s difficult to remember, I know, that conservative governments of yesteryear implemented some strikingly powerful and effective environmental legislation. Indeed, it was the former incarnation of the Coalition government that implemented the once-formidable Environmental Protection and Biodiversity Conservation (EPBC) Act under the direction of then Environment Minister, Robert Hill. A colossus of sorts, the EPBC suffers from many ailments. While it’s the only really bitey environmental legislation we’ve got, that colossus is a lumbering, limping giant missing more than a few teeth – it needs a complete overhaul.

As most Australians are unfortunately aware, The Monk repeatedly and defiantly promised to repeal the Labor-government carbon price implemented in July 2012, despite the absolute necessity to tax the heaviest pollutersWhile somewhat sheepish about his recent climate disruption denialism following his election in 2013, a denialist he remains:

Let us re-familiarise ourselves with some of his historical pearlers: Read the rest of this entry »





Biodiversity needs more than just unwanted leftovers

28 02 2014

calm oceanThe real measure of conservation progress, on land or in the sea, is how much biodiversity we save from threatening processes.

A new paper co-authored by Memorial University’s Dr Rodolphe Devillers and an international group of researchers argues that established global marine protected areas are too often a case of all show with no substance and do not adequately protect the most vulnerable areas of the world’s oceans.

“There is a big pressure internationally to expand global MPA coverage from around 3 % of the oceans to 10 %, resulting in a race from countries to protect large and often unused portions of their territorial waters for a minimal political cost,” said Mr. Devillers. “Marine protected areas are the cornerstone of marine conservation, but we are asking whether picking low-hanging fruit really makes a difference in the long-term, or if smaller areas currently under threat should be protected before, or at the same time as, those larger areas that are relatively inaccessible and therefore less used by people.

“We need to stop measuring conservation success in terms of square kilometres,” he added. “The real measure of conservation progress, on land or in the sea, is how much biodiversity we save from threatening processes. Metrics such as square kilometres or percentages of jurisdictions are notoriously unreliable in telling us about the true purpose of protected areas.” Read the rest of this entry »