Cartoon guide to biodiversity loss

30 01 2009

I’m taking Barry Brook‘s great idea on the Cartoon Guide to Global Warming Denial and applying it to biodiversity and habitat loss.

There are a lot of these sorts of things out there (amazing how we laugh at tragedy), so I will probably do subsequent posts as I find good candidates (suggestions welcome).

ucs-cartoonearthbin

CJA Bradshaw

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South Australian marine park boundaries released

29 01 2009

As an addendum to my last post (Marine Conservation in South Australia), I thought it worth mentioning that the South Australian government has released its plans for coastal marine parks. I have yet to look through these in detail, but public comment is welcomed until 27/03/2009. We’ll see what the fallout is.

Release approved by Allan Holmes, Chief Executive of the Department of Environment and Heritage (SA):

The outer boundaries of South Australia’s network of 19 new marine parks were proclaimed today. This exciting development will help protect our unique and diverse marine environment for future generations to use and enjoy, and will also position South Australia as a national leader in marine conservation.

The boundaries will be available for public comment until 27 March 2009. To support the public consultation, 57 public information sessions will be held across South Australia. To find out more about South Australia’s new marine parks network, visit here or ring 1800 006 120.

CJA Bradshaw





Marine conservation in South Australia

26 01 2009

© U.R. Zimmer

© U.R. Zimmer

Just before the holidays last year I participated in the Conservation Council of South Australia‘s (CCSA) Coast & Marine in a Changing Climate Summit 2008. It was an interesting, mature and intelligent summit with some good recommendation surfacing. Although I certainly didn’t agree with all the recommendations (view the entire report here), I must say up front that I have been very impressed with the CCSA’s approach in their ‘Blueprint’ summit series to address South Australia’s environmental problems.

Many environmental groups, especially regional ones, are seen by many as raving environists1 with little notion for balance or intelligent debate. CCSA is definitely not one of those. They are very careful to engage with scientists, public servants, industry leaders and politicians to hone their recommendations into something realistic and useful. Indeed, I am now certain the only way to convince people of the necessity of dealing with the world’s environmental mess is to make intelligent, scientifically defensible arguments about how environmental degradation worsens our quality of life (yes, this is the principal aim of ConservationBytes.com). So, good on the CCSA for a rationale approach.

Enough about the CCSA for now – let’s move onto some of their marine-related recommendations. I won’t reprint the entire summary document here, but a few things are worthy of repetition:

Significantly increase the amount of resources available for marine species research and taxonomy, especially for non-commercial species.

Despite my obvious conflict of interest, I couldn’t agree more. One of the principal problems with our ability to plan for inevitable environmental change to lessen the negative outcomes for biodiversity, industry and people in general is that we have for too long neglected marine research in Australia. Given that most Australians live near the coast and almost all of us rely on the oceans in some way, it is insane that marine research in this country is funded almost as an afterthought. How can we possibly know what we’re doing to our life-support system if we don’t even know how it works?

Take climate change for example. The majority of climate change predictions are merely single-species predictions based on physiological tolerances. Most almost completely ignore species interactions. Any given species must compete with, eat and be eaten by others, so it’s insane not to combine community relationships into predictive models.

A strict monitoring regime should be implemented in all ports and harbours to continuously monitor [sic] for introduced marine pests in order to inform better management, in conjunction with the species outlined in the Monitoring section of the National System for the Prevention and Management of Marine Pest Incursions.

Many people, and scientists in particular, have traditionally turned their noses up at so-called ‘monitoring’. However, as a few Australian colleagues of mine recently observed, the marine realm has a huge, gaping hole in monitoring data necessary to determine the future of Australia’s marine environment. Take it from me, a scientist who regularly uses time-series data to infer long-term patterns (see Publications), it’s essential that we have more long-term data on species distributions, reproductive output, survival, etc. to make inference about the future.

Recreational fishing should be licensed, with the license fees being directed towards increased research of non-commercial species and education of recreational fishers.

I really like this one. It seems South Australia is the only state in the country that doesn’t have mandatory recreational fishing licences. Absolute madness. Given the capacity of recreational fishing to outstrip commercial harvests for some species (e.g., King George whiting Sillaginodes punctatus), we need vastly better monitoring via licences to determine local impacts. Not to mention the necessary generation of money to support monitoring and research, which to the average recreational fisher, would not be such a hefty price to pay. The political drive to keep the status quo is woefully outdated and counter-productive. See one of my previous posts on the potential impacts of recreational fishing.

There is a need for a co-ordinated, state/Adelaide-wide stormwater strategy. Currently the Stormwater Management Authority examines individual projects but does not manage a bigger picture with a co-ordinated approach.

A colleague of mine recently published an article showing how South Australian waters, being more oligotrophic on average than other areas of the country, are particularly susceptible to nutrient overloading. The main losers are seagrasses and macroalgae (kelp) forests – the Adelaide metropolitan coast has lost up to 70 % of its kelp forests since major urbanisation began last century.

There are many more recommendations that you can peruse at your leisure, and many of them will be updated this year once the CCSA incorporates all the received comments. I thank them for the opportunity to take part in their worthy aims.

CJA Bradshaw

1My colleague, Barry Brook, invented this excellent term to describe those people who blindly support anything ‘green’ without really thinking of the consequences. It’s also a great way to differentiate serious ‘environmentalists’ and conservation biologists from raving ‘greenies’.

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How many frogs do we eat?

20 01 2009

IMG_20130209_141200A paper that my colleagues and I wrote soon to appear in Conservation Biology describes the massive worldwide trade in frog parts for human consumption. I bet you had no idea…

This report from New Scientst:

Are frogs being eaten to extinction? We’re used to hearing about how disease, climate change, and habitat degradation are endangering amphibians, but conservationists are warning that frogs could be going the same way as the cod. Gastronomic demand, they report, is depleting regional populations to the point of no return.

David Bickford of the National University of Singapore and colleagues have called for more regulation and monitoring in the global frog meat market in order to avoid species being “eaten to extinction”.

Statistics on imports and exports of frog legs are sparse as few countries keep track of the amount of meat harvested and consumed domestically.

According to UN figures, global trade has increased in the past 20 years. France – not surprisingly – and the US are the two largest importers; with France importing between 2500 and 4000 tonnes of frog meat each year since 1995.

But although frog legs are often thought of in the West as a quintessentially French dish, they are also very popular in Asia.

Bickford estimates that between 180 million to over a billion frogs are harvested each year. “That is based on both sound data and an estimate of local consumption for just Indonesia and China,” he says. “The actual number I suspect is quite a bit larger and my 180 million bare minimum is almost laughably conservative.”
Local depletion

Even top French chefs may be unaware of where their frogs are coming from. Bruno Stril, teaching chef at the Cordon Bleu school in Paris, France, is unsure where his suppliers source their frog legs. “I would like for them to come from France,” he says. But he expects that most of the meat comes from other countries.

Stril is on the right track. Indonesia is the world’s largest exporter of frog meat, exporting more than 5000 tonnes of frog meat each year, mostly to France, Belgium and Luxemburg.

Bickford and colleagues say European kitchens initially found their own supplies in the surrounding countryside, but the fact that they are now importing from Asia suggests local populations were over-harvested. This, they say, could be a sign that frog populations, like many fish populations, will be harvested to near extinction.

“Overexploitation in the seas has caused a chain reaction of fisheries collapses around the world,” the researchers write. “This experience should motivate better management of other exploited wild populations.”
Anonymous legs

James Collins, of the World Conservation Union, says the Californian red-legged frog offers some evidence for the theory. This species was first harvested for food in the 19th-century California gold rush and eventually the population began to crash.

However, Collins cautions that “at the moment we have no data indicating that commercial exploitation has led to the extinction of any amphibian species.” He says the Bickford team’s evidence is worrisome, but inconclusive.

Most harvested frogs are skinned, butchered and frozen before being shipped overseas. This makes it difficult to know exactly what species are being killed. Indonesia is thought to mostly export crab-eating frogs, giant Jana frogs, and American bullfrogs. How much meat is consumed within Indonesia’s borders is also something of a mystery. Some studies suggest it could be between two and seven times what is exported.

“There are a hell of a lot of frogs being eaten,” says Bickford. “Much more than most people have a clue about.”

Original article soon to appear: Warkentin, IG, D Bickford, NS Sodhi, CJA Bradshaw. 2009. Eating frogs into extinction. Conservation Biology DOI: 10.1111/j.1523-1739.2008.01165.x

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Just give them a lift

16 01 2009

TvyamNb-BivtNwcoxtkc5xGBuGkIMh_nj4UJHQKupCdpgnnqXqJ70oP0iCjWicCL0ROBPry44AuNOne of the main problems in a rapidly changing world, whether that change arises from habitat loss, invasive species or climate change, is that often the pace of change is simply too fast for many species to keep up. History (both ‘deep-time’ and contemporary evidence) tells us this fact very clearly in the record of extinctions – species that have ‘slow’ life histories (i.e., those that mature late in their lives, produce few young and breed infrequently) are the most susceptible to extinction. More often than not, these tend to be the big organisms because the pace of life scales to body size nonlinearly (the so-called allometry of vital rates). The problem extends to evolution – when the pace of change happens faster than mutation and subsequent natural selection, you are unable to ‘evolve’ to the new environmental state fast enough. The end result – extinction.

So, can we help? Well, it’s fairly difficult to alter reproductive rates unless you do some assisted breeding programme (which generally don’t do much for the conservation status of a species) and you can’t really alter age at maturity or growth rates. You can stop or reverse habitat destruction, and you can translocate species in some circumstances.

So, in the case of climate change, if local conditions become too unbearable for a species (temperature, salinity, precipitation, etc.), just give them a lift to another spot where the new conditions suit! Sounds simple, but it could be rather difficult.

A relatively new Policy Forum piece in Science outlines how ‘assisted colonisation‘ could work for some species. The issues are many – most translocations fail for one reason or another (too few individuals moved, unforeseen predators or competitors, lack of appropriate habitat, etc.), but as we’ve seen the world over in the case of successful alien species, invasions can be remarkably successful (at least from the perspective of the invading species).

The key then is to think very carefully about which species to move and which to leave alone. Of course, generalist, highly adaptable and dispersed species probably don’t need the help, but restricted-range species or habitat specialists could really benefit from such action. You also run the risk of creating more problems than you solve (e.g., new invasive pests, disease introduction). However, a select group of species might just need this very assistance to persist given how much we’ve already change the biosphere, and how much more it will change due to shifting climate in the near future.

It’s controversial, but it could work in many circumstances. That’s why I’m adding this paper (Hoegh-Guldberg et al. – Assisted colonization and rapid climate change) to the Potential list.

CJA Bradshaw

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Measuring the amphibian meltdown

9 01 2009

melting_frog_by_zarinstar.pngA paper my colleagues and I published earlier last year in the open-access journal PLoS One describes one of the largest databases of amphibian threat risk ever compiled. Our main aims were to determine which factors drive amphibians toward extinction – this being especially topical considering that amphibians epitomise the modern biodiversity crisis: major population declines, disease outbreaks, deformities and recent confirmed extinctions dominate the biodiversity news. 32 % of all amphibians worldwide are threatened with extinction, 43 % of described species are declining, and about 160 species have already gone extinct in the last few decades.

In our paper (Sodhi and colleagues) entitled Measuring the meltdown: drivers of global amphibian extinction and decline, we found that the range size occupied by a species was overwhelmingly the principal driver of threat risk. This means that although other factors are involved, the number one (by far and away) thing threatening amphibians is habitat loss – everything else is minor by comparison.

Of course, we shouldn’t ignore other issues – increasing climate seasonality (temperature and precipitation) also contributed to higher threat risk. This is exactly the sort of thing that is predicted to increase with climate change (more variable weather patterns). In many cases, it’s the variability that’s worse than the mean trend when it comes to biodiversity.

So what should we do? Our results suggest that areas containing high numbers of restricted-range amphibians should have conservation priority. Although captive breeding might help to buffer some declining populations in the short term, such interventions cannot substitute for habitat protection and restoration. The synergies between ecological/life history traits and environmental conditions demonstrate how management must address each of the major drivers of decline together for any success – there is no magic bullet to prevent extinctions. We also recommend that substantial increases in international research on the long-term monitoring of amphibian populations is required to mitigate effectively the current meltdown of amphibian biodiversity.

CJA Bradshaw

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Man bites shark

7 01 2009

cut-shark-finYesterday I had a comment piece of the same title posted on the ABC‘s Unleashed site. I have permission to reproduce it here on ConservationBytes.com.

The silly season is upon us again, and I don’t mean the commercial frenzy, the bizarre fascination with a white-bearded man or a Middle-Eastern baby, the over-indulgence at the barbie or hangovers persisting several days into the New Year. I mean it’s the time of year when beach-goers, surfers, and municipal and state policy makers go a bit ga-ga over sharks.

There are few more polite pleasures than heading down to the beach during the holidays for a surf, quick dip or just a laze under the brolly. Some would argue it’s an inalienable Australian right and that anything getting in our way should be condemned to no less than severe retribution. Well, in the case of sharks, that’s exactly what’s happened.

Apart from a good number of adrenalin-addicted surfers and mad marine scientists, most people are scared shitless by the prospect of even seeing a shark near the beach, let alone being bitten or eaten by one. I won’t bore you with some ill-advised, pseudo-psycho-analytical rant about how it’s all the fault of some dodgy 1970s film featuring a hypertrophied American shark; the simple fact is that putative prey don’t relish the thought of becoming a predator’s dinner.

So, Australia is famous for its nearly 100-year-old pioneering attempt to protect marine bathers from shark attack by setting an elaborate array of shark nets around the country’s more frequented beaches. Great, you say? Well, it’s actually not that nice.

Between December 1990 and April 2005, nearly 3500 sharks and rays were caught in NSW beach nets alone, of which 72 per cent were found dead. Shark spearing was a favourite past-time in the 1960s and 1970s, with at least one high-profile species, the grey nurse shark, gaining the dubious classification of Critically Endangered as a result. Over-fishing of reef sharks has absolutely hammered two formerly common species in the Great Barrier Reef, the whitetip and grey reef sharks (See the Ongoing Collapse of Coral-Reef Shark Populations report). And illegal Indonesian fishing in northern Australia is slowly depleting many shark species in a wave of protein mining that has now penetrated the Australian Exclusive Economic Zone.

Despite the gloomy outlook for sharks, I’m happy to say today that we are a little more aware of their plight and are making baby steps toward addressing the problems. Australia has generally fared better in shark conservation than most other parts of the world, even though we still have a lot of educating to do at home. Over 50 per cent of all chondrichthyans (i.e., sharks, rays and chimaeras) are threatened worldwide, with some of the largest and most wide-ranging species being hardest hit, including white sharks. The most common threat is over-fishing, but this is largely seen by the lay person as of little import simply because of the persistent attitude that “the only good shark is a dead shark”.

The attitude is, however, based on a complete furphy. I’m sure many readers would have seen some statistics like the following before, but let’s go through the motions just to be clear. Dying from or even being injured by a shark is utterly negligible. Based on the International Shark Attack File data for Australia, there were 110 confirmed (unprovoked) shark attacks in Australian waters between 1990 and 2007, of which 19 were fatal. Using Australian Bureau of Statistics human population data over the same period, this equates to an average of 0.032 attacks and 0.006 fatalities per 100,000 people, with no apparent trend over the last two decades.

Now let’s contrast. I won’t patronise you with strange comparative statistics like the probability of being killed by a (provoked) vending machine or by being hit by a bus, they are both substantially greater, but I will relate these figures to water-based activities. Drowning statistics for Australia (1992-1997) show that there were around 1.44 deaths per 100,000 people per year, or approximately 0.95 if just marine-related drownings are considered. These values are 240 (158 for marine-only) times higher than those arising from shark attack.

It’s just plainly, and mathematically, ridiculous to be worried about being eaten by a shark when swimming in Australia, whether or not there’s a beach net in place. The effort made, money spent and anxiety arising from the illogical fear that a shark will consider your sunburnt flesh a tasty alternative to its fishier sustenance is not only regrettable, it’s an outright crime against marine biodiversity. Of course, if you see a big shark lurking around your favourite beach, I wouldn’t recommend swimming over and giving it a friendly pat on the dorsal fin, but I wouldn’t recommend screaming that the marine equivalent of the apocalypse has just arrived either.

You may not be fussed either way, but consider this – the massive reduction in sharks worldwide is having a cascading effect on many of the ocean’s complex marine ecosystems. Being largely carnivorous, sharks are the ecological equivalent of community planners. Without them, herbivorous or coral-eating fish can quickly get out of control and literally destroy the food web. A great example comes from the Gulf of Mexico where the serial depletion of 14 species of large sharks has caused an explosion of the smaller cownose ray that formerly was kept in check by its bigger and hungrier cousins. The result: commercially harvested scallops in the region have now collapsed because of the hordes of shellfish-eating rays.

The day you fail to find sharks cruising your favourite beach is the day you should really start to worry.

CJA Bradshaw

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