Saturday 29 September 2012

Boars on the fairway - part 1


        Wild boars get bad press.
    In April 2009 the Standard described a nasty attack. A 77-year-old man was hospitalised after a boar pinned him to the ground and bit him in the groin, it said.
    According to the paper the boar got stuck in a fence earlier at a nearby house, a fairly common occurrence here. The pig freed itself after a struggle and shot off along a drainage ditch until it was blocked by a dead end that it was forced to high jump out of. It then ran up a hill, away from the village, but an outdoor rest area was in its path, where a group of pensioners were playing cards. It charged towards one man who fended it off with a bicycle, and then turned on another. The second man fought the animal off with a stick and held it at bay for a minute until the boar knocked him to the ground and sank its teeth into his groin. 
    A boar charging towards a group of men sounds unusual. Was that the full story? I checked with CT Shek at AFCD and this is what he told me:
    “In the past five years, only three incidents of minor injury of people caused by wild pigs have been reported and the most recent case was an elderly man slightly bitten by a wild pig when he was chasing the animal in his village in April 2009.”
    Shek's version of events was a lot milder than reported, casting blame also on the actions of a man who was going against AFCD advice to leave wild animals well alone. But of course “beast mauls man in groin” makes for a better story than “man chasing boar slightly injured.”
     Nine times out of ten the boar will come off worse in an encounter with a human, and yet we remain scared of them, because they look damn scary. In fact, when a hundred and fifty kilogram pig crashes out of the undergrowth to run wild in the streets, it is scary. You don't want to get in its way, especially when it is frightened, and if you can see it, it will be frightened. 
    But there are hardly ever any unprovoked attacks by boars. They have an unfortunate habit of crashing into us by accident, and that can lead to an entanglement, a panicked charge and a nasty nip. But that’s no more of an attack than a bird crashing through the window of an apartment, and smashing up ornaments in a panicked bid to escape.
    Compare the three minor boar injuries in a five year period with Hong Kong road accident statistics 2008 - 2013: more than 85,000 people injured, nearly 12,000 seriously, 636 people killed
   Now take a closer look at official boar data.
   446 “cases” were reported to AFCD in 2010, of which 40 percent were regarded as mere sightings or duplicates. 268 were considered “potential nuisance cases,” and of those 96 cases were judged to merit hunting operations. The numbers were lower in 2013, but still 56 wild pigs were shot that year after 260 “cases” were reported, that’s more than one boar execution a week.
    We can safely conclude that cars are much more dangerous than boars, but while we seem to accept a high level of deadly collateral damage from drivers, we have a very low tolerance for even slightly leery wild pigs.
    Recent incidents include a boar shot by a policeman with a hand gun on a housing estate after a tranquiliser dart failed. Another was shot after a five-hour rampage in a village house ended with the boar locked into a storage room, repeatedly charging the walls and door. 
    One died after police cordoned-off a neighbourhood of North Point district following the early morning discovery of a pair of sleeping hogs. The pigs stampeded after an officer tried to shoot one with a dart gun and missed. 
     Boars with their heads rammed into roadside crash barriers are not exactly a common sight, but they’re not far off a yearly occurrence. Usually firemen cut them free, but not all of them make it through the ordeal after sustaining self-inflicted injuries from a frantic struggle to prise free.
   
Boar in mainland China meeting the same fate as many
of its cousins in Hong Kong
 Considering the hazards, it is a wonder the animals come so close to the human environment, but they always have.
    Wild Boars are the largest truly wild, land animals that live and breed in Hong Kong. Feral cattle are larger but they are basically domestic animals left alone for several generations after economic changes made them redundant. We've got feral dogs too, but they are also the descendants of pets gone astray. 
    A proper wild boar is a beast born in the forests, from stock never domesticated by humans. They're often referred to as the ancestors of domestic pigs but they’re more like their wild, never domesticated cousins. The two forms of swine are the same species sharing the same Latin name sus scrofa. There are different breeds of pig, just as there are different breeds of dog, ranging from your pink cuddly porkies to the low slung pied-coated pot bellies, but they’re all sus scrofa and they all had ancestors that looked as ragged and wily as a Hong Kong boar.
    Wild boars should also not be mistaken for feral pigs, often hunted in North America and Australia, the descendants of domesticated pigs that have escaped from farms or been let loose for sport. If these variations are all the same species you might wander what is the point of distinguishing between them, but there are differences.
    Recent research in domestication of wild animals suggests genetic roots at the start of the process that brought a select group of species closer to humans. Boars, wolves and cats are thought to have all undergone a similar process. One theory is that a mutation of DNA prevented some individuals from being afraid of humans, and that gave them the willingness to take greater risks while scavenging on the waste by-products of settlements.  There was something about human habitations they liked, most probably food and a degree of security from other predators. They followed us from a distance, the bravest coming closer and getting more food, while risking spears and other ways in which humans could suddenly turn on them.
    As the most human-friendly animals interbred they passed on the genes that brought them closer to us. They were in effect breeding a domesticated strain of themselves. There were physical as well as behavioural changes. Their coats became less shaggy and ears flopped down, as did their tails. The process in pigs was likely accelerated around 10,000 years ago when humans took note, actively encouraged the relationship, and then started selectively breeding for the traits most useful to us. Docility and meatiness being two qualities sought in pigs, while cats for example were probably selected more for rat-catching skills, and the wolf-dogs fanned out into all sorts of services.
    The wild ones in the meantime stayed clear. They didn’t trust us. They chose a different path through the forest, but still on the fringes of the world we built. It is the descendants of the wild strain that appear out of Hong Kong’s woodlands to charge into the oncoming traffic, and get trapped in concrete drainage ditches.
    Like macaques, boars live in matriarchal family groups. Boar groups are called sounders, with up to 20 individuals. They sleep together in tightly packed rows, in territory marked by trees rubbed with their mud-caked bodies. Females with young aggressively defend their patch from any threats including hikers on the wrong path. Adolescent males get kicked out of sounders when they mature, to become solitary foragers, mostly avoiding each other’s company, until mating season, when violent showdowns are unavoidable for access to females. 
    Wild boars in Hong Kong are part of an ancient stock of primeval fauna that survived the territory’s centuries of deforestation, according to a study by the Wildlife Conservation Foundation. They are on an elite list of only nine species considered aboriginal, including esoteric specialists like the Chinese pangolin and the crab-eating mongoose. Their numbers had dropped by mid 20th century for them to be rated a rarity in the 1950s, but they survived the lean years to gain current official status as “very common and widespread.” There is not an official count of the animals, but they were the fourth most often spotted species in the 2002 -- 2006 camera trap survey, after porcupines, muntjack deer and Indian civets.
    A decade ago on Lamma Island there were no reports of wild boar, but slowly sightings became more common. It’s believed the first returnees swam across the channel from Hong Kong island, successfully negotiating one of the busiest shipping channels in the world. I came across one at rubbish bins about 200 m from my flat. A huge black pig had come down a steep wooded hill and was poking its snout in plastic bags, it stared me out for a second and then backed off into the woods. It waited for me to pass and then came out again, not concerned that I was still lingering to watch, having deduced that I had got to the side I wanted to be on. Since then I’ve seen the aftermath every few days, plastic bags torn open and dragged in to the forest, the access path worn into a muddy channel of churned soil.
   
AFCD
 The general belief is that the animals are fairing well in the territory, as they are reportedly doing so in many places around the globe, including Britain where they have been reintroduced, and Germany where recent invasions of the suburbs had led to calls for anti-pig fencing to be erected. Official sightings in Hong Kong climbed from 150 in 2006 to 446 in 2010. Mainland China also recorded a recent spike in the eastern provinces, including in the city of Hangzhou where swine were entering hospital dormitories and college kitchens. The total number in the province had risen five-fold in a decade according to the mainland press, to 150,000. The rise in eastern China has been blamed on the fall in natural predators such as wolves, as well as demographic changes emptying the countryside, as farmers head to cities for work
    



     
    

Sunday 23 September 2012

Monkey management in the urban jungle



You can see packs of wild monkeys marauding the forested hills of Kowloon and the New Territories, swinging and leaping through trees. They run around on reservoir service roads like ragged gangs of street urchins with dirty, urban-grey coats. They mark their territory with parcour skills any human practitioner could only dream of.
    I found them sheltering under tree leaves on a rainy afternoon, mothers picking fleas out of babies’ coats, juveniles shaking branches to pass the time, and fat patriarchs lazily slumped in branch nodes. They watched us, but left us unmolested.
    Their movements, their gaze, their fingers are all an uncanny reminder of ourselves. Like wild tribes of small hairy people, looking quizzically at us, unafraid, because they are used to us.
    Their dexterity is uncanny. They grab, prise, poke and pinch with gnarled fingers. Their short legs double as an extra pair of arms, the tail a fifth limb. Their faces are old, with deep wrinkles, giving a different meaning to the term old-world monkey used by zoologists to differentiate from American, or new-world, primates. But their large, intelligent eyes are young and bright. The babies and toddlers induce gushing empathy from people, they remind us of our own children.
    They are macaques, wild monkeys with a long history of interaction with humans. The species here are the rhesus, dominant with about two-thirds of the population, the others mostly being a hybrid of rhesus and long-tail macaques, also known as crab-eating macaques.
    The experts tell us that we're not looking at an indigenous population, despite records of passing naturalists in the 19th century who reported monkeys on all the islands that dot the territory. Deforestation during that century would have hit the original inhabitants hard, as would a rising human population uninhibited by hunting laws.
    The ancestors of the rhesus macaques were introduced to the woods surrounding the new Kowloon reservoir around the time of the first World War. Their task was to eat the poison-laced leaves of a plant that threatened to contaminate the city's drinking water.  
     
Source: Botanical.com
The strychnos is a formidable plant that exists around the world’s tropical belt and used by some Amazonian Indians for poison arrow tips. The synthesised version of the toxin, strychnine, has a long history as a tool of assassins and murderers, and was a particular favourite in the imagination of British crime writer Agatha Christie. The substance is notorious for delivering an agonising death by prolonged convulsions and violent muscle spasms. But macaques, though they are amongst our closest relatives, thrive on the leaves of the strychnos, so they got the job to patrol the reservoir and stayed ever since.
    The long-tails came after the second World War, originally with a passing circus troop, the story goes. The travelling show failed to get permission to take their monkeys to the next destination and they were forced to leave the macaques behind. These south-east Asian primates survived alongside the rhesus, and the two species went on to interbreed.
    Going by geographical spread, the rhesus macaques are the most successful monkey species in the world. Their natural range stretches from Afghanistan in the west to south east Asia, with close relatives such as the long-tails dotted all round the periphery. Japanese macaques live all through Honshu island, and are known to survive in the most northerly latitudes of all wild primates, famously getting by in winter by keeping warm in hot spring baths.
    In Hong Kong they are mostly based around Kamshan in Kowloon, as well as Lion Rock and Shing Mun country parks. The species is notably missing on Hong Kong island itself, though past records show previous populations.
    Studies from around 30 years ago found a much smaller population of monkeys than we have today. Researchers in 1981 counted 81 macaques, but toward the end of the decade the numbers dipped to 72. Urbanisation and the invasion of the countryside by leisure seekers were blamed for the falling monkey trend. But this conclusion was turned on its head in the following years. The 600 found in 1991 suggests that the previous count might not have been the full picture. The average ten percent annual rise tracked from then on showed a clear population growth. Monkeys were out-breeding the stress-laden people of Hong Kong, one newspaper reported.
    The animals are fabulously popular. Who doesn’t love a monkey, especially ones that have the cheek to beg for nuts? Monkey feeding became a popular Hong Kong pastime. Just outside of densely packed residential zones there are big swathes of greenery, fantastic woodlands that are good for monkeys, and easy for humans to reach. Over the past thirty years, since people discovered that leisure could actually be a part of a Hong Kong lifestyle, there has been a steady stream of city-folk going up the hills to feed wild monkeys.
Source: AFCD

    The activity offers a counter-balance to Hong Kong life, normally seen as a joyless urban grind in the pursuit of money. Visiting monkeys in the woodlands provides access to wildlife and greenery, it is good for children and it is good for the elderly. Feeding them is even better, some people think, an act of benevolence with environmentalist overtones.
    But it doesn’t quite work like that. The macaques may appear to thrive, as their population growth suggests, but their decadent lifestyle is ultimately endangering their existence. Even world-famous primate expert Jane Goodall made comments about our humble troops. She noted they were eating junk food and getting obese. She strongly urged a feeding ban. 
    It isn’t just a matter of health. Human feeding of monkeys is turning them into fat, lazy thugs. Many of the primates have lost their natural fear of people and have become increasingly aggressive in the pursuit of food. In some cases monkeys that started life as beggars have turned into blatant muggers.  They are in danger of abandoning their natural foraging behaviour, in favour of free handouts from humans, or if that doesn’t work, daylight robbery. The very success of the strategy of scrounging off humans is endangering them on several levels, perhaps most crucially, by annoying their human hosts.
    Recent human-animal conflicts have included a 46-year old hiker who was hospitalised after falling 20 metres into a reservoir trying to flee a pack of macaques. She suffered head, arm and leg injuries as the wild animals lunged for a bag of nuts she happened to be carrying. Another woman ended up in hospital after being mugged for a box of egg tarts. Both cases beg the question, what were these people doing in well-known monkey territory visibly carrying food?
    The conflict goes both ways, though the level violence is one-sided. Monkeys have been stabbed to death by humans, they have been hunted, trapped and butchered. Evidence of monkey hunting has triggered rumours of an underground trade for the mainland wild meat market. A local newspaper reported the slaughter of 300 monkeys in 2009, according to a group of people who volunteered to protect monkeys. AFCD were unable to confirm the report, but the story reflects the concern that followed the known attacks.
    A feeding ban has been in place since 1997 and banners on footpaths near monkey troops clearly state that giving food to macaques can lead to a maximum 10,000 Hong Kong dollar fine. But some habits are nearly impossible to stamp out. AFCD told me in 2011 that they had fined 104 people for illegal feeding in the previous year. It seems like a high prosecution rate, but the number of people successfully charged is always going to be a fraction of the real number of offenders.
    I have seen people throwing cakes, biscuits and bread from car windows, and I’ve seen scattered fruit peelings, and other debris of human food on monkey paths. A quick search on YouTube reveals any number of fools filming themselves handing out sweets, pastries and bananas. Travellers’ blogs marvel at monkeys biting into cans of beer.
    The problem could be that AFCD are going too soft on the feeders. The average fine in 2010 came in at 567 Hong Kong dollars, less than 6 percent of the prohibitive 10,000 people are threatened with.
    More than 500 monkey nuisance cases were logged by AFCD in 2013, better than the 2006 peak of 1,400, but still a lot of complaints about monkeys behaving badly. This is no new problem around the world, especially with macaques which have a particularly long history of interaction with human society. A study in India found that almost half the rhesus macaque population lived in cities, towns and villages. Another 37 percent had regular contact with humans along roads and canal banks, leaving just 14 percent of them living completely apart from people. Given the close relationship that macaques have always had with humans we have to ask what we really mean by the natural environment of these species?
    
Credit: Saskia Dijk Uni of Kent
It isn’t easy to answer that, but in Hong Kong something had to be done to restore a more “natural” relationship between people and monkeys. So our solution was to put them on contraceptives.
    Experiments in monkey birth control started some 15 years ago when a batch of females were injected with a contraceptive called SpayVac, which produces antibodies that cause eggs to reject sperm. Elsewhere in the world the same stuff has been used on horses, deer, seals and wolves. But Hong Kong was the first to try it out on feral monkeys. It is a temporary measure allowing for normal sexual behaviour while providing sterility for 3 to 5 years. At the same time some males were permanently vasectomised with another type of injected contraceptive.
    Capturing animals for the scheme turned out to be more difficult than experts had estimated. The problem was that monkeys quickly learned that government agents were after them. Most capture methods could only be used a few times before the animals learned to avoid them. Sometimes an alfa male would recognise a cage, so he would police the trap and forbid young monkeys from entering. Other times the leaders directly attacked AFCD staff. Government capture methods included net-guns, cage traps, drugged food, live decoys, dart-guns, food traps, and snares. Before long the monkeys recognised individual AFCD staff and their vehicles. They would scatter their clan and scarper as soon as they spotted agents. Not suprisingly the capture stage took months longer than planned.
    Despite these teething problems, the contraceptive scheme has been viewed a success. After the initial trials by AFCD, the work was subcontracted to the private sector, including the Ocean Park Conservation Foundation. Ocean Park introduced another type of surgical vasectomy for females, rendering them permenantly sterile. 
Monkey examination: AFP

    I watched the capture and medical examination of a group under the direction of Italian vet Paulo Martelli.  Part of a troop had been lured into a large custom made walk-in cage left in place for long enough to allow the monkeys to become confident. For days feeders recognised and trusted by the macaques kept a fresh supply of food inside the cages, but little known to the primates, their suppliers were double-agents working for the government. They wait for a moment when the cage is at its fullest, then shut the doors by remote control while the unsuspecting animals feast on without a care. Once trapped, Martelli and team arrive, complete with vials of ketamine that knock the monkeys out. It is only then that the monkeys start to panic. The cages have moving parts that press macaques against the side where an anaethetist can get at a limb with a hypodermic needle.
     Knocked-out monkeys are dunked in disinfectant and laid out on a trolley in a field hospital quickly put together on-site by a team of experts, technicians and vetinary students. 
     “Between the uterus and the ovaries there are small tubes that we cut out in very precise keyhole surgery. We go in, remove two pieces of tube and come out. It takes a few minutes,” Martelli told me.
     Once the operation or examination is complete the animals are laid out in a recovery cage four or five at a time, which then opens into the main communal section as they shrug off their ketamine hangover. When they are all ready the doors of the main section are opened and the monkeys bolt for their lives. The dozen I saw shoot out of the trap could not have reached the tree tops faster if they had been able to fly. 
      The progamme is not about eliminating the population, it’s about making it possible for the wild animals to continue to co-exist with us in the city. As of 2014 about 2,700 individuals had undergone some form of contraceptive process and the current population is estimated to be around 2,000, distributed in 30 social groups. Numbers are down about 15 percent since 2009 and the birthrate has dropped by more than half, suggesting a continued reduction in the number of newborns in the coming years, according to CT Shek at AFCD.
     I asked him what the 'ideal' macaque population would be, but he replied that there is no set goal and complaints against the beasts would continue to be monitored. He emphasised that birth control was only part of the programme and public education was also necessary, to teach people how to co-exist with monkeys. And as Karthi Martelli, project manager with the Ocean Park conseration group, pointed out, “It really depends on what people can tolerate. Sometimes sighting a monkey is the reason for a person to call. This would be recorded as a nuisance complaint even if the monkey hasn’t done anything. I always tell people: mind your monkey manners. When you’re scared you do stupid things and people blame the monkeys. If you ignore the monkey and walk away they get bored too. They don’t plot to attack.”
    
Since Hong Kong's pioneering venture into wild monkey birth control other authorities have followed suit in macaque havens including Malaysia, Singapore and India. But human involvement with the species goes much deeper than the micro-management of feral populations trialed here.
    Scientific experiments on the species, who share 93 percent of our genes, have bound these animals to our fate for decades already, and the relationship continues. It is ironic that while Hong Kong is a testing ground on the use of contraceptives to control feral macaques, the same species has been used to test the effectiveness and safety of human contraceptives. But contraceptives are the tip of the iceberg when it comes to macaque contributions to science.
    Rhesus macaques define our blood types from before we are born. The Rhesus factor is an indicator of how likely it is that the immune system of a pregnant mother will attack the blood group of her unborn child. The name rhesus stuck because the phenomenon was understood after experiments with blood from the rhesus macaque.
    Other than that the species have been test subjects for research on polio, malaria, neurology, obesity, HIV, and dementia, to list a selection of recent studies. They have also made contributions to psychology, sociology, bio-warfare and thought controlled prosthetics.
    The species was the first primate to achieve space flight, reaching orbit well before Yuri Gagarin’s 1961 mark, though admittedly under human direction and without consent. It was also the second primate to have its gene sequence completely de-coded, following the publication of the human genome in 2001. Comparison showed a 93 percent identity between us and rhesus macaques, who we last shared a common ancestor with 25-million-years ago. The chimpanzee genome was completed two years later in 2005, showing a last common ancestor with humans just 6-million-years ago, and a 98 percent match with our DNA. Referring back to the macaque genome sheds light on how humans and chimps evolved separately. In particular it shows which genes humans gained, or even which ones we lost to make us human.
    Scientific interest in macaques has generated a lucrative trade that continues today. In the 1960s India exported up to 50,000 macaques a year, mostly for biological research. The trade was so large that it threatened wild populations of the monkey species and the country banned exports in 1978. Soon after that China established macaque breeding programmes to plug the gap in the market, fuelled mostly by the demands of pharmaceutical companies in the US and Europe. Now with 23 established breeding centres, China is the world’s biggest supplier of rhesus and long-tailed macaques for experiments, according to a paper published by Conservation International. There is a good argument that a country like China that tolerates little dissent is convenient to western drug companies for locating breeding centres for lab-monkeys, away from the scrutiny of animal rights campaigners.
    The lab-monkey trade received a boost in 2004 after the passage of 'project bioshield' into United States’ law. The bill provided a 5.6 billion dollar budget for research to bolster defenses against biological attacks by terrorists.  Its passage was helped by a massive political boost from the September 2001 terrorist attacks on American soil.
    The hijackings on that day killed all passengers and crew of four domestic flights and some 3,000 people on the ground in New York’s World Trade Centre towers. Those events led to strong demand that security weaknesses should be fixed, and the political pressure to pour cash into solutions. People needed to feel safe, and one area of vulnerability was seen in the threat of bio-terrorism.
    Even under normal conditions biological warfare has sinister overtones, but when an anthrax attack disseminated through the US postal system only weeks after the 9/11 hijackings, people were terrified. Five people died and 17 people sickened in the worst biological attack in US history. 
     
Photo: AP
In a truly baffling turn of events we now know that the only official suspect in the case remains a disgruntled FBI specialist in germ warfare who committed suicide before he was brought to trial. And in the attacks, he used anthrax spores developed in a US government lab. But despite the bizare homegrown source of the attack, the political will to act against germ warfare had already been unleashed. So US lawmakers made billions of dollars available to pharmaceutical companies offering solutions against the external bio-terrorist threat. Suddenly drug firms needed monkeys to test antidotes to anthrax, botulism and nerve gas.  After all, you can’t test the effects of bio-warfare on human volunteers.
    One species in particular – long-tailed macaques – came into demand, with devastating consequences on populations close to Hong Kong, according to a 2008 article published by Conservation International for the IUCN.
    Cambodia’s long-tailed population has been decimated in the wild since 2003, mostly for export to China and the US, argued researcher Ardith Eudey in the paper. Although China’s breeding centres supply the legal trade in macaques, demand outstripped supply for several years. And Eudey argued that wild animals caught in Cambodia were being laundered into the market through legitimate fronts. The process appears to start in farms that have special licences to breed from captured animals. The resulting offspring from these breeding centres are legally traded for export, but they help to mask the underground trade in animals caught in the wild.
    Live macaques are caught in rainforests, often by felling trees to isolate them, and then passed on to the international market with forged CITES documents, transiting through Vietnam and China. In 2007 the US officially imported about 24,000 long-tailed macaques, 7,000 more than just three years earlier. US buyers paid an average of $1,475 per monkey in 2008, while suppliers at the other end of the chain earned about 55 dollars for each macaque. In 2012 official data showed about 15,000 imports to the US, with 56 percent of them coming from China and 8 percent from Cambodia.
    Recognising the pressure that long-tailed macaques came under after India’s ban on exporting rhesus macaques, there are calls to re-evaluate the ‘least concern’ status of the species under IUCN listings. Eudey said that the Cambodian population of wild macaques had become virtually extinct, forcing traders to look wider for supply. In 2007 Malaysia lifted a ban on the export of macaques, after law makers argued that controls were needed on the exploding urban population. Hong Kong’s population has never been large enough for any serious consideration to exploit for profit, but considering that some new monkey breeding centres have been set up with Hong Kong investment, the idea must have at least crossed some minds.
    Here there is official will to protect and preserve the macaque population, even if the ideal demographic hasn’t yet been decided. The contractive programme is seen as a successful management plan, with broad approval from conservationists and animal rights groups. There are many good reasons to preserve the feral beasts, not least because they are incredibly clever, with powers of intellect that sometimes reach mythological proportions.
    Never mind the odd individual monkey that can learn how to open car doors or unscrew water bottle tops. One troop of gifted macaques has been trained to shoot AK-47s at US soldiers. So said The People’s Daily, the official newspaper of China’s ruling communist party. The story appeared online on June 28, 2010 and accompanying photos were even highlighted in the editor’s picks. It claimed that Taliban warlords had trained macaques to use Kalashnikovs, Bren light machine guns and trench grenades. They learned to spot US soldiers by their uniform, and shoot at them. It was an instructive story, not so much about the genius of monkeys, of which it revealed nothing, but about the stupidity that official state media is capable of falling to. Experts universally derided the claims, saying it was impossible to teach monkey's to use AK-47s against “enemy” combatants.
    In man’s world, full of violence and lies, it’s no wonder that monkeys sometimes run scared. With dwindling forest populations, thousands of brethren kidnapped for the lucrative lab-monkey trade, and well meaning vets lining up to castrate them, there may well be reason for a monkey to make a bid for freedom. And that’s exactly what one Hong Kong macaque did some years back, though he was probably running in the wrong direction. 
    A two-day chase started when someone spotted a wild primate at the Tsim Sha Tsui ferry pier at the end of Kowloon’s “Golden mile” shopping district. He was separated from the normal wild monkey zone by about four kilometres of densely rammed shopping malls, thundering bus-lanes, and jammed housing blocks. Police and government vets pursued the monkey for ten hours that hot July day, until the feral beast slipped from their sights as darkness set in. Officials spotted the animal early the next day, but again lost sight of it near the waterfront tourist spot after five hours. 
    The next sighting puzzled the vets, police and government agents who were frantically looking for the wild interloper. It appeared on the other side of Victoria harbour, near the Wan Chai ferry pier. It may have stowed away on a Star Ferry, or found its way across the harbour tunnel, perhaps hitching a ride on a truck. Or did it even swim? No one knows, but the animal continued to evade capture on Hong Kong side. It crashed through the hurly burley of Wan Chai’s red light district, and into Causeway Bay’s throng of shoppers. Dozens of officials chased the beast, through backstreets, into malls and even inside shops, as word spread among a growing crowd of spectators and supporters.
    By the time the plucky beast was finally brought down by tranquilliser dart it had well and truly earned Hong Kong celebrity status.       

Monday 10 September 2012

Giant spiders and the quest for bio-steel -- part 2

Credit: V&A
Spider sex may interest some specialists, but knowledge of spiders in the wider public mostly reduces down to two basic facts. They are scary, and they make webs. We've covered scary. Now it's time to look at their silk. Hong Kong's nephilas represent the most awesome web spinners in the spider world. Any footpath that falls out of use in spring will be festooned with golden orb webs very quickly, as I discovered on a hike on Lantau when I fell off the beaten path. As I followed the trail deeper into the hill side, the spider webs were cast closer to the ground, forcing me to duck lower. Each one inhabited by a dangling nephila, ready to sink her fangs into anything vaguely edible, like a human ear or a blindly placed finger. When webs hung too low I had to bash them with sticks, and I felt the surprising drag of the silk. 
    A nephila has six spinnerets at the end of its abdomen, which work to spin one of the strongest materials in the natural world. Protein molecules in liquid form are physically rearranged into a line of silk and squeezed out through tiny tubes. Seven different types of spider silk have been identified, each with a different quality to serve specific functions. These include strong radial spokes to support the main frame of the web, sticky orb lines to trap prey, draglines used during construction of the web, silk to entrap and wrap around struggling prey, soft lining material for egg sacks. 
    This versatile material is pound for pound five times stronger than steel, and three times stronger than Kevlar, the stuff of body armour and spaceships, according to online journal Chemical and Engineering News. Spiders spin it out in fine lines a tenth of the width of human hair, but a single strand can stop a speeding bee in mid flight.  A typical hiker is probably several thousand times bigger than a golden orb web spider but anyone who has bashed through a web can testify to the power of those microscopic spindles.  
    I once jumped through a web on a run. I took a short cut on a path that had been unused for some time because large bin bags obstructed the end of it. I accelerated to get a run-up to launch over the bags, only to fly face first into an enormous web. There was a large ripping sound, like wrenching fresh Velcro. Then a yell from me, followed by loud swearing. My first thought was to make sure the animal that wove the net was nowhere near my body. 
    I accelerated like Usain Bolt out of the starting block, and slapped myself raw. I never met the artisan but her silk wrapped me with an unnerving power, I was still peeling it off a mile down the road. 
    Spider silk clearly is something special and people around the world have made use of its properties for generations. It has been woven into nets to snare birds or clumped together into sticky balls to catch jumping fish. People have used it for bandages, stuffed into wounds to stem bleeding. A friend who grew up in Guangdong province told me how in childhood he would create a loop from reedy wood and scoop up a web into a ready made net. He used these to catch cicadas, which he would stuff with corn kernals, bake and eat. 
Spider inspired securitybot: reuters

    Today's materials scientists have said that finding a reliable source of the stuff is the “holy grail” of the textiles industry. It's not just the strength that is sought, it's also the flexibility of the line, being able to stretch to 40 percent of its length. On top of that, made from water and proteins, the stuff is a completely biodegradable natural material, a huge advantage over its polluting artificial rival, Kevlar, synthesized from nasty sulphuric acid. 
    Among the products lined up are lightweight body armour, parachutes, airbags, surgical sutures, artificial tendons, and even braking cables for fighter jets landing on aircraft carriers. But so far the quest to mass produce this wonder material to its full strength has remained elusive.
    The most obvious approach would be farming. Silk worm farming has gone on for centuries, making a huge cultural impact across the world. A quick count of nephilas on a Hong Kong hike would tell you that these awesome spiders are thriving. So how hard would it be to farm them? The answer so far is impossible. 
    The root of the problem lies in the very nature of spiders. They are cannibals and they do not cohabit. They instinctively know this from the moment they are born, their first task in life being to get away from their siblings as quickly as possible, before they get eaten, or they have to eat a brother or sister.  
    I had a demonstration of this one night when a huntsman egg sack burst open on my ceiling. I first noticed it when I switched on the light and looked up to see tiny specks spreading above me in all directions. Some spread horizontally while others were absailing downwards on tiny thread, like minute secret service assassins. There was a neat geometric pattern as the hundreds of spiderlings kept up a radiating equidistance from each other. My girlfriend was not amused, and I’m afraid that generation didn’t make it past nature’s first line of selective pressures, though I secretly hoped that one or two might have escaped to live well in a more welcoming home. 
    Farming requires cohabitation, and that doesn’t work for species that have a tendency to eat each other. But this didn’t stop an inspired French missionary in Madagascar from reviving a traditional nephila silk spinning machine in the 1880s. Father Jacob Paul Camboue, apparently turned to local folklore to create a device that could harness 24 spiders side-by-side in separate match-box pens. Their silk was "milked" by a hand driven winding crank, and woven into a workable thread. There is a record of a “complete set of bed hangings” made from spider silk, exhibited at the Paris Expo in 1898, although it isn’t known what happened to the sample set. 
    Some years back a group of textile experts fascinated by the qualities of spider silk built a replica of Comboue’s invention. Their painstaking work over four years produced an11ft by 4ft golden tapestry, manufactured from an estimated 1 million golden orb web spiders caught in the wild by 70 collectors.  The project leaders having thus demonstrated the impracticality of extracting silk at the rate of one ounce per 14,000 spiders bestowed the exquisite cloth to the American Museum of Natural History in New York in 2009     
     Now there is one major avenue of hope for those seeking the “holy grail” of spider silk, and that is in genetics. 
    Canadian start-up Nexia Biotechnologies, with an initial investment of $2.5 million, took up the quest for “biosteel” during the 1990s. Silk wasn’t the first product the firm focused on, but soon after spider DNA had been isolated, the enterprising laboratory turned its attention on the promise of manufacturing the world’s strongest natural material. They had strong backing from both the US and the Canadian defence agencies, keen to find a reliable source for future lightweight body armour, amongst other potential military uses.
    The big excitement came in 2000 when the company presented the world's first goats genetically modified with spider genes, irresistibly nicknamed the spider-goats. Goats may seem a strange choice, but they have the advantage of being compatible for farming, fast breeding and cheap. The technical reason for making spider-goats was that the mammary glands of goats are remarkably similar in structure to the silk producing glands in spiders, according to the scientists involved. 
    But in addition, the spider-goat was a marketing dream. It had to be, the juxtaposition of the dark mysterious arachnid with the thoroughly domesticated and humble goat had both comic and sinister overtones.  It already had a superhero precedent in spider man, which only fueled the incredible claims being made for the end product such as the inch thick cable that could suspend a jumbo jet. When the company floated on the stock market in December of the same year, the initial public offering fetched $42.4 million, one of the biggest hauls for a Canadian biotech IPO.
    The initial transgenic pair were, surprisingly, both males. But that worked, as they were able to successfully pass on their designer genes to new generations. The future looked good, too good to be true, and indeed there was a hitch.
A goat

    Three or four years down the line mass production still hadn’t started.  Despite the promise offered by similar mammary and silk producing glands, the spider goats didn't actually spin webs from their teats. Instead the silk proteins needed to be filtered out of the milk and purified into a white powder before being spun into thread. What is more goat silk was found to be only one-third of the strength of spider silk.
    A couple of years later, side-by-side with the the US Army, Nexia announced a welcome breakthrough in silk production, although cows had taken the place of goats, by providing the cells that became the source material for the production of artificial silk. With or without goats, there was, once again, great excitement about medical sutures, biodegradable fishing lines and soft body armour. It looked like commercial viability was on the horizon.
    But the next big announcement from Nexia came in 2004 and it went in a surprisingly different direction. It had nothing to do with spider goats or biosteel. Instead, working with the US Army’s Institute for Chemical Defense the company announced that transgenic goats had been successfully involved in experiments to protect animals from the effects of nerve gas. There were no super tough lightweight materials, no biodegradable suspension bridge cables, or even environmentally friendly fishing lines. Just a mysterious product called protexia, that could one day help soldiers withstand a chemical attack. 
    Two years later, Nexia had gone bust, and a herd of 40 unemployed “Franken-goats” were left on a farm in Canada. 
    Nexia failed, but the quest for artificial spider-silk is far from over. The University of Wyoming bought the goats in 2007, brought them to the United States, and continued to research ways of making spider silk a commercial viability.  The academic institution entered into a commercial deal with another biotech firm with a big idea, Kraig Labs. 
    Kraig announced in September 2010 that they had successfully engineered silk worms to carry spider genes. A product that doesn’t quite have the intrigue value of spider-goats, yet seems so inherently commonsensical that you can’t help but wonder why it took ten years to get from goats to silk worms. Initial results were promising with the relatively farmable silk worms producing spider enhanced high-grade silk. But the thread whilst doubling on the strength of un-tampered silk, hadn’t attained the power of spider thread. 
    The company has tinkered away at the quest over the years and continues to make promising announcements. To date it has created about 20 different types of spider silk fibers, with its lead product known as “monster silk,” a combination of spider and silkworm proteins and “significantly stronger and more flexible than commercial grade silk.” 
    But still that is not the elusive spider-strength threads of tomorrow’s body armor, bionic tendons and and suspension-bridge cables. 

    And so while humans may have invented nuclear power, genetic engineering and brain surgery, we still haven’t worked out how to mass-produce spider thread, a material so desirable that the strongest armies in the world have invested millions to crack its code. The holy grail remains unclaimed, for now.
Spider spinnerets. Credit: MicroAngela
     








    
    
   

Sunday 9 September 2012

Giant spiders and the quest for bio-steel - part 1


     
There is something completely alien about the gigantic golden orb web spider that appears in Hong Kong’s woodlands each summer.  Size plays a role in forming an other-worldly impression. Made up of eight metallic legs splaying out of a chunky five-centimetre body, it would cover a good adult hand. But it’s not just the shocking dimensions. It’s the shiny robotic body parts, like a Kevlar exoskeleton created by NASA, with tribal yellow markings, painted on as toxic warnings to stay clear. A closer look reveals dangling palps that scoop liquefied prey into its mouth. But unless you’ve got too close you won’t see the real weapons she keeps tucked up until a victim is within grasp. The fangs open sideways and slam shut to pierce prey in a paralysing grip. If you’re getting that perspective you’re probably a moth or a cicada living the final moments of your brief life, you may catch a glimpse of eight beady eyes looking into the depth of your dying arthropod soul.
     Perhaps the almost-as-large huntsman spiders that often cohabit with unsuspecting Hong Kongers are just as alien. They also have eight eyes and eight legs. But they have something pet-like that makes them easier to relate to.  They’ve got visibly furry bodies like ours, almost mammalian, and they like living inside flats, like us. Not so with the golden orb webs, these have no interest in the cosy world of domesticated man, they are forest dwellers. They would thrive just as well in a post-apocalyptic world purged of humanity. The huntsmans would probably do alright too, but surely they would miss the undersides of our sofas and the shiny roundness of our bath tubs. The golden orb webs wouldn’t even notice we had gone.  
Same species, Singapore.
Credit: Joseph KH Koh
    On any hike in summer you would have to be blind to miss the golden orb web spiders, and if you were blind there would be in danger of walking into one of their webs. They build the world’s biggest, spanning up to two metres across. As their name suggests, they have a golden tint to them, almost sparkling when sunlight hits at the right angle. These webs are not hidden out of sight deep in the forest, they are cast wide across open space, exploiting all the likely insect flyways. The spider sits near the middle, dark and angular, irresistibly drawing your gaze, almost evil.  The highly visible golden orb web, also known as the large woodland spider is part of the large nephila family of arachnids, nephila pilipes in Hong Kong. They don’t hide, they are avoided. Even wild animals are scared of nephila. In Hong Kong birds and bats have been ensnared in their silk. Stuck, entangled and certainly doomed in the world’s strongest webs.  
Credit: Les Martin
    The question is whether the giant spiders eat these larger animals. Nephila have the poison to paralyse, the silk to wrap and the enzymes to digest flesh, but birds and mammals are unlikely to be their intended target. Photographs of an Australian nephila cousin wrapping a trapped bird, and apparently chewing on it, emerged in a Queensland newspaper a few years ago. Experts confirmed that a golden orb web making food parcels out of bird flesh was nothing new. But even the strongest silk in the world gets badly damaged by the death throws of a bird, and so it seems that nephila generally prefer to avoid bird strikes.  They are known to build barrier nets in front of their main webs, decorated with discarded body parts of more manageable prey, as well as leaves and twigs, to create a visible warning -- spider here, might kill, stay away.  Such acts imply intelligence, so does the casting of nets on lampposts. 
    I saw the webs on several lampposts that lined a coastal hike to a small hamlet. Along a kilometre stretch the posts were evenly placed every 100 metres or so, nephila webs fixed on each crook, formed between vertical poles and the arms that reached over the footpath. It was a woody rural walk, but the tops of the lamp posts were several metres away from the edge of the vegetation. At dusk the advantage of such strategic web placing was obvious, as insects swarmed the orange glow a few centimetres from fat spiders. But how does the spider “know” that would be good place to build? Its behaviour seems to imply calculation, including the observation of insect behaviour, and a consideration of the inverted L shape of the lamppost forming the perfect frame for a web. Do they think, like we do?  
    Before we fall too far down an anthropomorphic road to confusion, it’s as well to remind ourselves that spiders are nothing like us, at all. Like insects they are arthropods, and so any genes we share with them are buried deep in our DNA archives, hundreds of millions of years old. We branched off from their family even before the backbone was invented. Spiders offer a thoroughly alternative model of life that may as well have come from outer-space when we look at some of the basic details.  
    They have two main sections to their body, a front end that holds eyes and mouth, and a back end that they excrete from. So far so good, but as noted before, they have eight eyes. Try drawing an eight-eyed animal, and see if you can possibly avoid it looking alien. Unlikely. But the eyes are not even that good at seeing. Orb weaving spiders sense the world through vibrations and chemistry. Hairs on their legs are finely tuned to detect and interpret movement on their web, which itself becomes an external sensory organ. And the tips of their legs are equiped with probes that can detect chemical changes, such as vital information that a female nearby might just accept insemination without necessarily eating its suitor.  
Credit: visual dictionary online
    The front end of the body, considered a fused head and thorax, is where the legs radiate from. That would be like your arms and legs sticking out from your neck, or dangling below your chin, all four pairs.  The back end, called the abdomen, contains the heart, as well as primitive lungs, made from evolved gills, indicating a "recent" previous aquatic existance. Air also enters the body through a kind of straw lodged near the anus. There are no veins or arteries, blood floods the body, swamping the organs, all contained in the waxy exoskeleton the spider sheds as it grows. 
    Compared to spiders, even civet cats with their feral ways are our close kin.  But if the basic anatomy of a spider confounds the expectations of a normal person, such as the average hiker on Hong Kong’s hills, their feeding habits are likely to upset the squeamish. 
    All spiders are predators and most of them are venomous, though only a small number are harmful to humans. Depending on the species, the venom falls into two large groups, the neurotoxins which mess with the nervous system, and the necrotics which cause cells around the bite area to die off.  Commercial interest in extracting or synthesising spider poisons focus on pesticides and drugs for cardiac patients.
    Nephilia are equipped with a neurotoxin that befuddles brain signals in the victim. The spider pumps the poison into the body of its prey, usually an insect, through hypodermic fangs, paralysing the victim though not necessarily killing. It then tightly wraps the insect up in silk to thwart any chance of escape when the poison wears off. Once secured, the spider liquifies the insect with digestive enzymes, sucking it dry until the husk of an exoskeleton is all that's left. 
    As devastating as this may be to a small animal, to humans the effect of a bite has been compared to a wasp or bee sting. In any case in Hong Kong it's not a common occurrence, as despite the menacing look of a golden orb web, the spider is a reluctant biter of people, unlikely to sink its fangs into you unless provoked. 
    The work of hunting and securing food is done by large female Nephila, but theives are never far away, including mite-sized kleptoparasites called argyrodes, and Nephila males lurking in the corner of the web trying to survive long enough to mate. Argyrode spiders wait until a meal has been wrapped, taking advantage of nephila's tendency to store food for some time before tucking in. The thieving spider ingeniously fools the nephila's sensitive trip-wires by securing the food with external drag lines, and methodically cutting the web around it without giving away any movement. With the final snip the contraband is transfered to the argyrode's silk line and pulled clear from the unsuspected giant at the centre of  the web. 
    The males of the species can also be mistaken for parasites. They are tiny compared to the females. Most casual viewers do not notice the reddish 5 to 10 mm bodied boy-spiders lurking in the corners of a massive web. Like argyrodes, they also steal from the female, but who can blame them, they have to stay alive long enough to fulfill the task of mating.  Female spiders are known for eating anything that gets within grabbing distance, so life is precarious for the spindly males. Males of some spider species use elaborate dance moves in the lead up to mating, to persuade the female not to eat them. The ritual is like a password to prove he is of the same species.  One wrong step and the female will take him for a pretender, which she will have to kill and consume. 
    Nephila males take a different approach that helps to explain the sexual dimorphism of the species. They go for stealth, by sneaking up on the female while she’s feeding, climbing onto her gigantic abdomen, and inseminating her before she notices. Spider sex is a strange methodical act where the male uses his dangling mouth palps to carefully place little packages of sperm in her genital openings. Having done this the male will soon shrivel and die. The female will have about a month left to feed, climb down to the ground, make a silk lined egg chamber, lay her fertilised eggs and then die. 
    It’s usually around March that the first nephila webs of the year appear in Hong Kong forests. They start off a modest 50 or 60 centimetres across, policed near the centre by an unassuming 2 centimetre female. It is hard to believe that she’ll turn into the giant arachnid of nightmares within months. 

Saturday 8 September 2012

Creationist's nightmare - part 2

Borrowed from visitbalionline.com
 Mudskippers are an obvious and clear example of evolution in action, as they daily play out the prehistoric drama of life pushing beyond its oceanic nursery. It is no simple matter that animals that evolved for millions of years under water, made their way on to land. That’s one of the reasons that evolutionary biologists are drawn to mudskippers. When fish broke the water barrier they triggered an explosion of vertebrate diversity that flowered into amphibians, reptiles, birds and mammals, including us. So the big question when we’re looking at the mudskippers on the shores of Lantau, is: are we staring at one of our most important ancestors? 
    Unfortunately the answer is no. 
    So called “bony fishes” split into to two major branches more than 400 million years ago. The “ ray-finned bony fishes” and the “lobe-finned bony fishes” evolved completely separately. Living examples of the “ray-fins” include most of the commonly known fish such as carp, pufferfish and mudskippers. “Lobe-fins” alive today are more obscure, but they include lungfish, which have much more sophisticated air breathing adaptations than mudskippers, and coelacanths which were once thought to be extinct, until one turned up in a fisherman’s by-catch. It was the lobe-finned fishes that first crutch-walked and skipped out of the ocean, developed limbs, and walked off into the forest as tetrapods ñ or four-footed animals. They gave rise to all the other vertebrates including geckos, snakes, eagles, civet cats and monkeys.
    So “our” ancestors left the ocean independently of mudskippers. 
    But thanks to convergent evolution, we might well see in a mudskipper an animal remarkably similar to a human ancestor. And for that same reason, we can learn a lot about life from mudskippers. 
    Convergent evolution comes about when species that don’t share a “recent” ancestor independently evolve similar solutions to common environmental pressures. Their whole form could be similar to each other, or they might have similar body parts. Dolphins, for example have a similar shape to sharks, including fin or flipper swimming aids, and torpedo bodies to cut through the water. But sharks are fish whose ancestors never left the water, and dolphins are mammals whose ancestors walked on land on all fours. As predecessors of dolphins gradually adapted to life in the oceans, their legs dropped off, and they slowly evolved to resemble sharks.
http://bio-ditrl.sunsite.ualberta.ca/detail/?P_MNO=1800

    Elsewhere bats and birds independently evolved wings, as did moths. And bats developed sonar to catch moths long before humans developed radar on the same principles to guide fighter jets in warfare. And humans were playing a game of catch-up with moths when they created radar-evading stealth fighters. 
     Gadgets are worth mentioning because they show that our solutions to the restrictions of the environment are limited to certain choices by the universal laws of physics and chemistry. These same laws force convergence on animals that adapt to similar environments.
    The mudskipper’s constant companion on the mudflats is the fiddler crab, abundant in Hong Kong in the same places the skippers skip. They are popular attractions with their massively distorted single giant claw that they wave to show-off in the tidal zone. The fiddlers are invertebrates, no closer related to mudskippers than we are to shrimp. But the eyes of these two unrelated species sit in equivalent positions on their bodies, prominently atop the highest points.  On mudskippers they bulge above the crown of their heads, and on the crabs they wave high on stalks. The forces that pushed these eyes upwards are the same for both species, the need to see what’s happening above the water while their bodies are protectively hidden. The top position gives them the information they need before they venture out of the water. Watch the tide suck out of a mud flat and you’ll see beady eyes appear first, species indistinguishable until bodies emerge creeping and crawling, like a creationists’ nightmare.
AFCD

    But creationists are adept at wriggling out of a tight spot. “Of course these animals are similarly adapted to the environment, God made them that way so they can live there,” they’ll say, perhaps even suggesting that God may as well have saved time by using similar design solutions for the eyes of both species. There are no “transition” species in the eyes of creationists, because the so called transitionals just happen to be the animals that are perfectly crafted for the environment that God put them in, of course.
    The creationists live in a strange timeless world, where the present always has been and will continue to be, until the apocalypse. I much prefer seeing mutability in a fish that walks on land, a reminder of the fact that life changes, and we’re all just passing through. A mudskipper can inspire awe about the ancient origins of life, and optimism, for the constant search for better environments, and new modes of existence.
    Though, for some, they just inspire lunch.
    When I first learned about these excellent fish, I assumed that they wouldn’t taste good, otherwise I would have been offered one on a plate at some point in my life, surely. But I was wrong, there is a little-known niche for mudskipper-eaters across the tropics from West Africa to southeast Asia, and beyond the tropics to Japan, where the most northerly representatives of the family are eaten as a specialty on the island of Kyushu. Depending on local tastes the fish can be roasted, boiled, or eaten raw. In Yemen the fish are dried, pulverised, and dissolved in hot water and honey.
    Like a lot of traditional foods, Mudskippers are also prescribed for medicine. And as with much traditional medicine, there’s often some vaguely described link to sexual performance. From the honey flavoured beverage in Yemen, to Papua New Guinnea and China, people have ingested mudskippers in the belief that their sex lives would improve. Though I haven't seen a convincing theory of how walking fish can help out in the bedroom.
    I found one account from Malaysia about a man who swallows five live mudskippers a day, to prop up his apparently flagging libido. He said he had learned the secret from his father who had 16 children, which he took as evidence that there was something in it.
    But when you look at the huge range of animals, in whole or in parts, that have been passed off as tonics for boosting carnal desire and performance, it’s difficult to find a common link between them. Usually it is little more than suggestive shapes, and admittedly mudskippers do look like wet willies with fat heads sometimes. The idea that eating things that look like willies boosts the libido seems ridiculously simplistic, but I guess it is also testimony to the eternal human capacity for optimism.
    But swallowing mudskippers live could be a big mistake, especially if they’re taken from the wrong place. Although the fish are regarded as edible, with no particular toxins associated under normal conditions, they can absorb and accumulate pollutants from the environment. Because of this they are recognised by environmentalists as useful “biomonitors” for poisons that wash into the inter-tidal zone. Studies in Hong Kong in the Mai po marshes have shown worrying effects from two polluted streams, the Yuen Long creek and the Shenzhen river, that pour into brackish marshland of the Deep Bay estuary. Mudskippers have been found to be amongst the most contaminated species on the mudflats, recording high concentrations of heavy metals and insecticides.  This is disturbing, both for any human tempted to snack on the amphibious morsel, and for the thousands of hungry birds that fly in from distant breeding grounds, to shelter and fatten up in the renowned wetland sanctuary.

    Concern about a toxin build-up in mudskippers is not just a matter of being sentimental about some endearingly eccentric fish with chubby cheeks. As so-called “biomonitors” they indicate the state of health of the wider ecosystem, connecting aquatic life to the terrestrial. Finding a bunch of them along Hong Kong’s shoreline is a good sign for that particular locality, even if pollutants can be measured.  It shows that there is still enough life in the zone to keep the skippers alive, from various nutritious algae, to aquatic snails, little crustaceans, and small fishes. And as long as the skippers are fattening on that salty soup of flora and fauna, bigger predators remain attracted to the shoreline. These include other fish that catch the skippers in high tide, as well as terrestrial beasts such as snakes, lizards and of course beautiful shorebirds such as storks and pelicans. And as long as these keep coming, local mongoose and leopard cats have something to hang about for, as well as apex predators from afar such as raptors from Siberia and central Asia.