Archive November 2011

“Trade fuels demand”: Phrases that should be banned Brendan Moyle Nov 28


There are many phrases that cause me to wince. The oft-used ‘missing-link‘, beloved by newspaper headline writers, creationists and 1950s B-movie writers is one.  Another that is stubbornly popular in conservation literature is the oft-repeated claim that trade will fuel demand for wildlife parts.  This is typically used as a reason why trade in wildlife (or their parts) should not be allowed.

There are of course, legitimate reasons why trade could lead to increases in sales of wildlife parts (both legal and illegal). These are issues like laundering, a conspicuous problem during the 1980s with elephants.  Now, I would really prefer to debate these sorts of real reasons trade generates risks.

Instead we end up going over the same old ground, time after time.  Wildlife apparently is different to other economic products.  The act of making these goods available is sufficient to cause people to want them. Poor McDonalds or the like, have to spend advertising dollars in an effort to get customers into their stores. All wildlife producers have to apparently, is make their stuff available. It practically sells itself.

This is rather counter to our evidence. The trade in rhino horn has been banned since the 1970s, and despite proposals from time-to-time to have a legal trade (a legal harvest could simply remove horn from time-to-time on living animals), we’ve not seen that this has curbed demand. Poaching levels have remained unsustainable, populations of rhinos have been wiped out, and the price has soared from $US500 per kg in the 1980s to $50,000 per kg now.

Now, we don’t really have the counter-factual available here (would rhinos do better with some system of trade?), and the increase in price could also be sustained by the decline in supply.  So let’s have a bit more of a formal look at another example.

The idea behind trade fueling demand could be manifested in a couple of ways.  First, if I increase the supply of wildlife products in one year, this should increase demand (and sales) in the following year.  More people will want these products as their demand has been piqued. So increases in supply should lead to further increases in sales, decreases likewise.

The second way is via prices. If we’re increasing sales, is that because we’ve increased production and the market has cleared at this higher output? Or is it because demand has increased.  Well, a key variable there would be prices.  If prices go up- even as we’re increasing production- this would also imply supply is fueling demand.

So lets have a look at the Louisiana alligator production.  It’s a classic wildlife product, and at one stage subject to unsustainable harvests. It’s also a long data set, as the production and harvest level go back to the early 1970s.  This should be long enough to pick up any trends.

So, first question- does an increase in production in say one year, lead to an increase in production in the following:

Red line- the actual data from the Louisiana alligator market
Green line- the estimated data based using the previous year’s production as the predictor
Blue line- the residuals, the graph of the difference between the actual and estimated values.  The tighter and closer this graph is to the 0-line, the better the fit.

Regression: Farmed Skin Supply

Regression: Farmed Skin Supply

The regression had no significant fit here whatsoever, neither does the previous years supply have any effect on this years.  So this quick and simple test doesn’t support trade fueling demand. The blue-residual line is extremely volatile, reflecting the insignificant fit.

Let’s then consider whether there might be a price effect from this supply.  Again, I want to know if an increase (or decrease) in supply in a previous year will fuel (or correspondingly, reduce) demand in the current year.

Regression: Production and Prices

Regression: Production and Prices

And once again, there’s absolutely no relationship. The quantity supplied in the previous year has no detectable influence on prices. We’re not able to fuel demand here by our supply-decisions.

The third point is that maybe, it’s not that legal trade fuels demand for the farmed (or ranched products), but that it fuels the demand for the wild product. This may better reflect the concern conservationists have.  It is also something we can again test.  Louisiana has wild harvests operating alongside their farmed output. So lets see if our farmed output is affecting our wild harvest levels.


Again, there’s no relationship. Supply decisions in the farmed industry in a previous year, have no effect on either the price or the output of the wild skins in the current year.

In summary, there’s no good reason to give wildlife a special status.  There are certainly good reasons why a legal trade could increase conservation risks.  But the supposition that it will fuel demand is not one of them. The evidence we have from trade in wildlife products is that the usual market parameters drive demand. There’s nothing unique about wildlife that would cause a departure from this.

One also suspects that the opposition to trade in many cases is based on the charisma of the wildlife involved, rather than inherent conservation reasons.  It’s clear that there’s more opposition to say, trade in rhino parts than there is in alligator or crocodile.

A pair of swallow photos Brendan Moyle Nov 20

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These are some swallow pictures taken back in 2007 with my first DSLR. This was the Sony a100. The shots were taken at ISO800 for the shutter speed, but this also introduced a lot of noise to the image. The a100 was characterised by a weak AA filter and a CCD sensor. This often made for sharp images at low ISOs but much noisier ones anything above ISO400.

I've used Adobe Lightroom 3 here to process the images again. This is a much better tool to dealing with image noise. I made two versions of each shot. One version was developed with an aggressive approach to noise. The second version was developed with detail being emphasised. The two shots were then merged.

I like this shot for the fact the swallow spotted a midge above its head. I had no idea at the time it was present until I had the image viewed on the PC :)

Losing the battle to save rhinos Brendan Moyle Nov 14

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The upsurge in poaching of the Asian and African rhino species has continued for the last few years. Underlining this is the declaration from the IUCN that the Western subspecies of the black rhino is extinct. This is sad news in light of the once prolific numbers of this species. At the beginning of the 20th century there were an estimated 100,000 black rhinos in Africa. Their range extended from below the Sahara all the way to the Cape. In 1960, there were still an estimated 60,000 of these large animals.[1]

This is an animal that in the past had little to fear from predation. Elephants and lions are wary of these animals. The black rhino can gallop at 50 km per hour and easily smash their way through thorn brush. The threat it faces is well known. Rhinos are hunted for their horns. This slaughter has been unsustainable. By the late 90s, only one unfenced population of more than 100 animals existed (Namibia).[1]

White Rhino picture- via

So what in a nutshell has gone wrong?
Well, we've gambled nearly everything on one premise. That is if the trade in rhino horn is illegal, then demand will disappear. This premise has driven conservation policy decade after decade. And it ultimately it has failed. The loss of the western black rhino emphasises this.

Another measure of how badly the policy has failed is the price of rhino horn. Rhino horn has reputed values of between $40-60,000 per kilogram. In the period 1982-86 the average price of African horn was $538 per kilogram.[2] An adult rhino can have horn weighing up to 5 kg (albeit average weights are lower). In short, no collapse in horn-prices has been observed. Rather rhino horn has become one of the most expensive wildlife products on the planet (in comparison, a tiger is worth about $US50,000 in the black market).

A dead rhino in effect, is worth over $US250,000 to the poaching syndicate that is trafficking it. It's difficult to see how this is acting as much of a deterrent to poachers. The current prices are sufficiently high that killing dehorned rhinos still makes economic sense. There is enough horn left in the stump to make the effort worthwhile.

Demand in Asia has remained stubbornly high. This is despite anti-consumption campaigns. This is despite law enforcement. This is despite attempts at suasion. China banned the trade in rhino horn in 1993, and at the same time purged mention of rhino-horn medicine in TCM guides. Demand for rhino horn is based on three main uses. The first is in the Middle- East where they're used as jambiyyas- a type of dagger handle. The second is in China and Vietnam where it is used as an ingredient for traditional medicines (as a cardiotonic or antipyretic)[2]. The third and emerging use is as a reputed anti-cancer agent.

It is worth repeating that rhino horn is not used as an aphrodisiac. There is no research in TCM that supports it having this trait. Its use as a cure for impotence is not mentioned in any TCM texts. Middle-aged men who encounter problems getting a hard-on are not the cause of the rhino's demise.

One suspects that if we had been using legal trade over the last 30 years and had achieved this outcome, conservationists would be clamouring for a change in policy. Instead, the loss of the Western black rhino is unlikely to alter the situation at all. Many conservationists will continue championing the current strategy of banning trade and relying on law enforcement to save the rhino.

We are now trying to confront sophisticated crime networks, who are better equipped than many of the local enforcement agencies. The demand in Asia is indifferent to Western concern and it has been unaffected by anti-consumption campaigns. It is hard to see that the current plan to save rhino numbers has a realistic chance of succeeding. It is perhaps time, to be debating other options.

[1] Cunningham, C., and Berger, J. (1997). Horn of Darkness: Rhinos on the Edge. Oxford University press.
[2] Mainka, S.A. and Mills, J. (1995). Wildlife and Traditional Chinese Medicine- Supply and Demand for Wildlife Species. Journal of Zoo and Wildlife Medicine 26(2): 193-200.

Some photography thoughts Brendan Moyle Nov 08

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Well it's a challenge when mired in grading to think about blog posts. Or photography. Mostly coffee seems to be near the top of my wish list…

Well, I've done a major revamp of my photography website, so if crocodiles are your thing, stop by and let me know how it looks. If that doesn't appeal there are also fluffy ducklings. Mostly I've gone from having a light background to dark to hopefully, make the photos look more appealing.

I'm still dabbling with the NEX-5 mirrorless camera. I'm finding the system to be very appealing. The combination of compactness and image quality is a potent mix.

Nonetheless, I won't be selling my SLR gear for a number of reasons. I take a lot of macro photographs and a lot of wildlife. The flash system of the NEX-5 is rather inadequate for macro photography. It's a bit of a shame as the manual focusing system is very very good. The wildlife and bird photography- well, the NEX system lacks the long telephotos for this kind of work and the autofocus system is just too slow.

Customising the white-balance on the NEX-5 Brendan Moyle Nov 05

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I put together a quick 2 minute clip using a webcam on how to set a custom white-balance with the Nex-5.

While I've used a purpose white-card for calibrating, there are lots of other things that can be used instead. Ideally the subject needs to be exposed to the same sort of light as the light falling on the card.