[SCMP Column] Guardian of the Galaxy

August 12, 2017

My fascination with the challenge we face from invasive species was wrenched to a wholly stratospheric level last week when I learned that NASA is offering a salary of up to US$187,000 for a “planetary protection officer” tasked to protect the world from alien invasion.

I don’t know whether to be in awe at the mission, or appalled at the naivety. Given the marvellous job we have done here on earth protecting our various nations from animal, insect and plant invasions, I am intrigued to know what a single NASA employee is going to achieve.

And this ignores a single massive “Catch 22” at the heart of all efforts to prevent species invasion: that we human beings, now numbering more than 7 billion, are the single most significant invader worldwide, and are the principle vector for most other species invasions. If we are the policemen, who on earth (or across the universe) is going to police the policeman?

Even before reading about NASA’s hunt for a planetary protection officer, my interest in the problems of species invasion had been piqued over the past month by other factors. Last week travelling close to the awesome wildfires sweeping across the mountain forests of British Columbia, Canadian friends reminded me of the critical role played by north Asia’s Emerald Ash borer, which has eaten into and killed millions of Canada’s forest trees, leaving them tinder dry and vulnerable to any passing bolt of lightning.

That invariably led on to complaints and hand-wringing over a long list of invaders – from European green crabs and zebra mussels, to Gypsy Moths and Asian Longhorn beetles (which are jeopardising the Canadian maple syrup industry), to purple loosestrife marching across the countryside, and the delectably named “rock snot”, or didymo, whose slimy mats make rivers look horribly polluted.

And then in Japan there is the present scare over red fire ants, which originated in south America, but have managed massive incursions into the United States, Australia, China and Taiwan, attracting huge extermination and management programmes. In the US alone, officials say that fire ants cost the US economy about US$7bn a year in terms of damage, and control.

I remember writing just over a year ago about these venomous aggressors launching a reign of terror over large tracts of Hong Kong village land, but don’t so far see any big dollars being spent to purge them. It seems we in Hong Kong tend to “Keep Calm and Carry On” – unlike the Japanese who are seeking advice from New Zealand and Taiwan on eradication programmes including sniffer beagles and pesticide-laden drones.

So far, Japan’s invasive species spotters have found just 1,200 red fire ants (marching off container ships in Kobe, Tokyo and Osaka), so it is perhaps premature for Japanese to work up too much of a sweat. But given that the average red ant nest amounts to around 300,000 citizens, and that a queen can lay tens of thousands of eggs a day, perhaps vigilance is justified.

There really is not a territory anywhere in the world that does not have one or more invasive species to complain about. And one country’s furry friend is often demonised if it somehow finds itself playing away from home. New Zealand has long regretted importing deer and rabbits and dogs and cats (Maoris also apparently brought in cats). So too importing sparrows to eat insects and bring a bit of life to the empty hedgerows.

Germans have become very fed up with the racoons that stocked fur farms in the 1920s, and have now gone feral across the country. Americans wage war against a multitude of exotic invaders – from Burmese python which now regularly wrestle with alligators in Florida’s swamps, and Asian carp that first spread through the Mississippi, Iowa and Illinois river systems and have now invaded the Great Lakes; to starlings brought in by Shakespeare enthusiasts in the 1890s, and Asian citrus psyllids, which have infected citrus trees across the country and are threatening the country’s orange juice industry.

If you are in the UK, complaints commonly focus on grey squirrels, American mink and muntjac deer, and on rhododendron bushes that have run rampant in spectacular springtime colour across large parts of the British countryside, a legacy of Britain’s intrepid Victorian flower collectors. And then of course British country lovers recall wistfully the demise of elm trees, victim in the 1960s to attacks from elm bark beetle and an introduced European bark beetle.

Admirable though these xenophobic anti-immigrant efforts are, my sense is that many of these battles against foreign invaders, and the many billions of dollars spent (the US alone spends over US$130bn a year), are forlornly in vain. I am reminded by fellow SCMP columnist Jean-Pierre Lehman that it was Charles Darwin who observed that “it is not the strongest species that survive, nor the most intelligent, but the ones most responsive to change”.

We humans have performed quite well on this count, but set against most of our invasive species, we have much to learn – and perhaps much to fear. The Smithsonian Museum’s “BugInfo” site says there are around 900,000 insect species known to man, and a further 30m or so we have yet to discover. They estimate there are around 200m insects to every human, and around 40m ants per human – which is about 50,000 trillion for anyone with the patience to count all the noughts.

The Scientific American put it all into perspective a couple of months ago when a columnist calculated that there were more than 25m metric tonnes of spiders worldwide, which together eat about 700m tonnes of food a year. Given that the total weight of all the world’s humans is around 300m tonnes, he noted that spiders could eat the entire human population, and then still be hungry. Thank goodness they don’t find us tasty.

As for NASA’s planetary protection officer, I wish him or her well, but suspect that in our lifetimes, it is going to be the predator within rather than any mischievous inter-planetary predator harasses us. For now, I’ll keep watching out for fire ants – and hungry spiders.
David Dodwell researches and writes about global, regional and Hong Kong challenges from a Hong Kong point of view. Opinions expressed are entirely his own. 
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