Tuesday 15 May 2018

Troublesome trawling: how New Zealand's fishing industry hid the truth about by-kill

I recently signed a petition to reduce by-kill in New Zealand waters by installing cameras on all commercial fishing vessels. Forest and Bird and World Wildlife Fund New Zealand are jointly campaigning for this monitoring, as only a small percentage of boats as yet have cameras. The previous New Zealand government agreed to the wider introduction, but Fisheries Minister Stuart Nash is considering reversing this due to industry pressure. Considering that the current administration is a coalition involving the Green Party, this seems highly ironic. Is this yet another nail in the coffin of New Zealand's tourist brand as 100% Pure?

Despite requests from the fishing industry not to release it to the public, on-board footage shows the extent of the by-kill. High numbers of rare and endangered species have been drowned in nets, from seabirds such as wandering albatross and yellow-eyed penguins/hoiho, to cetaceans (there are thought to be only fifty or so Māui's dolphin/popoto left), seals and sea lions.

Many of the cameras already installed on New Zealand boats failed in the first three months due to inadequate waterproofing; when allied with the fact that the supplier of the technology was an integrated part of the seafood industry, there's more than a whiff of something fishy going on. Although official statistics are often considered to be of dubious quality, Occam's razor can be used to decipher the by-kill figures as they have been reported in the past decade. Only three percent of New Zealand's set net boats are officially monitored, yet they account for the vast majority of the recorded by-kill. Given a choice between sheer coincidence (i.e. only monitored vessels are catching large numbers of non-target species) and severe under-reporting from unmonitored boats, it is obvious that the latter hypothesis follows the law of parsimony.

Sadly, widespread deception by New Zealand's fishing industry isn't something new. A third-party report involving undercover operatives stated that between 1950 and 2010 up to 2.7 times the official tonnage of fish was actually being caught, peaking in 1990. All this comes from an industry that is laden with checks and measures, not to mention sustainability certificates. Killing marine mammals within the country's Exclusive Economic Zone isn't just a minor inconvenience: since 1978 it's been illegal, with severe fines and even prison sentences for those convicted. Small wonder then that the majority of by-kill has been undeclared.

What is equally sad is the lack of interest from the New Zealand public in resolving the problems. After all, over ninety percent of the population are not vegetarian, so we must assume the vast majority enjoy seafood in their diet. The rapid replacement of over-fished sharks with Humboldt squid in the Sea of Cortez off Mexico's Pacific coast shows how the removal of a key species can severely affect food webs. If New Zealanders are to continue to enjoy eating fish with their chips, the sea needs better protection.

Over the past decade, other nations have shown commitment to reducing by-kill and lessening waste. In 2010 the British celebrity chef Hugh Fearnley-Whittingstall launched the Fish Fight campaign to stop the discard of about half of the European Union's catch (due to it being either undersized or from non-quota species). Immense public support over the subsequent four years led to phased changes in the European Union's Common Fisheries Policy, proof that citizen action can make fundamental improvements.

Incidentally, it wasn't even a case of division along party lines; I was living in the UK at the time and wrote to my Labour Member of Parliament, who replied in a typically circumlocutory fashion that she would look into the matter! Even the then Conservative Prime Minister David Cameron agreed that EU policy needed a radical overhaul, a rare instance of cross-party sense and sensibility over pride and prejudice.

So what solutions are there to reducing by-kill? After all, installing cameras would only be the first step in assessing the scale of the problem, not removing it. Since Australia started monitoring its long-line tuna fleet, there has been a whopping seven hundred percent increase in the reporting of seabird and marine mammal by-kill. Some seaboard states in the USA have already banned set netting, which is still in widespread use in New Zealand. Several areas around the New Zealand coast such as between Kaipara Harbour and Mokau already prohibit this method of fishing - in this case to protect the few remaining Māui's dolphin - so there are precedents.

In addition, there are programmes currently testing new technology that may provide the answer. In 2002 the now charitable trust Southern Seabird Solutions was created to reduce by-kill of albatross and other endangered pelagic species.  This alliance of fishing industry leaders, recreational fishers, researchers and government analysts are trialling wondrously-named devices such as the Brady Bird Baffler, Hook Pod, tori lines and warp scarers.

Elsewhere, nocturnal experiments have been conducted using acoustic pingers to deter dolphins, although the results to date aren't especially promising. Equally dubious is the amended trawl net design for squid fishing vessels that incorporates the Sea Lion Exclusion Device (SLED); only today, it was reported that a juvenile sea lion had been found dead in such a net. Clearly, STEM ingenuity is being brought into play, but it will require further development and widespread introduction of the best solutions without industry interference in order to minimalise by-kill.

There are also some simple changes of practice that don't require equipment, only for the boat crews to be more aware of wildlife and act accordingly. Such procedures include moving away from areas with marine mammals present, not dumping offal, recovering lost gear, and changing the operating depth and retrieval speed of nets.

As usual, the financial considerations have taken precedence over the ecological ones. New Zealand has a comparatively small economy and as seafood is the nation's fifth largest export earner - over one billion dollars annually - it is hardly surprising that successive governments have tended to side with industry rather than environmentalists. However, could it be that there is now enough apprehension about the general state of the oceans to overhaul the sector's laissez faire practice? After all, in 2007 a fishing ban in New Zealand waters was placed on orange roughy, whose rapid decline caused huge concern.

There are of course plenty of other environmental issues affecting marine life: plastic pollution (including microbeads); increasing temperature and acidity, the latter especially drastic for shellfish; offshore algal blooms due to agricultural nutrient run-off; and numerous problems created by the oil and gas industry, from spillages to the far less reported exploratory air guns that impact cetacean behaviour.

The longer I've been writing this blog the more I'm convinced that science cannot be considered independent of the wider society in which it exists. Social, political and religious pressures and viewpoints can all adversely affect both what research is funded, what the time constraints are and how the results are presented or even skewed in favour of a particular outcome.

In the case outlined above, government ministries hid evidence to protect short-term industry profits at the expense of long-term environmental degradation - and of course the increase in public spending the latter will require for mitigation. New Zealand's precious dairy sector is already taking a pounding for the problems it has knowingly generated, so no doubt the fishing industry is keen to avoid a similar fate.

By allowing such sectors to regulate and police themselves and thus avoid public transparency, the entire nation suffers in the long run. We don't know what the decline or disappearance of populations of for example wandering albatross and Māui's dolphins might have on the (dis)appearance of snapper or blue cod at the dinner table, but as the alarming loss of Mediterranean and Californian anchovies and sardines suggests, negative cascades in the food chain can occur with extreme rapidity. Natural selection is a wonderful method of evolution but we are pushing it to the limit if we expect it to cope with the radical changes we are making to the environment at such a high speed. By-kill is something we can reduce, but only if industry and governments give science and the public a 'fair go'. Now isn't that something New Zealanders are supposed to be good at?

Saturday 14 April 2018

Avian Einsteins: are some bird species as clever as primates?


One of the strangest examples of animal behaviour I've ever seen in real life took place in my neighbourhood last year, with what for all intents and purposes appeared to be a vigil or wake. Half a dozen Common myna birds (Acridotheres tristis) were gathered in a circle around a dead or dying member of their species, making the occasional muted noise. Unfortunately I was rushing to get to work and didn't stop to take a photograph, which was a shame as the birds ignored me even when I passed within a few metres of them.

Even though the street was a cul-de-sac, I couldn't help thinking that sitting in the road was not the safest place for the birds to congregate, considering that they could have stayed close by on the grass verge; instead their proximity to the central, non-moving individual seemed to override their concerns for personal safety. 

Some biologists have suggested that this behaviour, mostly known from corvids (that is, the crow family) is due to the birds' instinctive need to advertise the area to others as particularly dangerous. Although there are plenty of cats in my neighbourhood this idea doesn't seem to make sense, at least in this particular instance. There were several trees that would have served as convenient perching locations for the myna birds, who weren't nearly as loud as they usually are.

Without getting too anthropomorphic about it, they were a lot less garrulous than normal, implying a sombre occasion. Far from providing warnings about the locality, the birds were extremely quiet for a gathering of this size; I should know, as myna birds are probably the third or fourth most common species in my garden and their routine screeches and squawks are far from subtle, to say the least. 

So is it possible that despite one of their number no longer moving or making sounds, its fellow birds understood that this inanimate object was one of their kind?  I've occasionally found dead birds of other species such as goldfinches, song thrushes and blackbirds in my garden and none have been the subject of similar behaviour. As an amateur scientist - or indeed anyone with curiosity might do - I researched the subject and found that crows are well known for gathering around bodies of the same species while magpies (another corvid) have even been reported as covering up dead fellows with twigs and the like. Are these reports all April Fool jokes or are some species of Aves unsung geniuses?

Further enquiry led me to discover that the corvid family, which includes ravens and jays, is the pinnacle of avian intelligence, closely followed by parrots. I initially thought that my observations of the myna bird, a member of the Sturnidae family, constituted something new, until I read a 2014 report from the School of Biological Sciences in Malaysia stating that laboratory testing proved them to be better at counting food items than House crows (Corvus splendens). In certain situations then, myna birds are up there with the brainiest of their kind.

In January this year I received another surprise on reading that the three most common avian raptors in northern Australia's tropical savannas - the Brown falcon (Falco berigora), the Black kite (Milvus migrans) and the Whistling kite (Haliastur sphenurus) - have been reported as deliberately spreading bush fires. It appears that after lightning has started a wild fire, the birds pick up burning twigs in their beaks or claws and drop them on untouched forest or grassland some tens of metres away. This then causes prey items such as lizards, snakes, rodents and amphibians to flee the new fire zone, only to be picked off by the waiting raptors.

Although birds of prey in North and South America, West African and Papua New Guinea are known to hunt on the edges of wild fires, the ingenuity of their Australian counterparts is without precedent.  What's more, they appear to have been using this behaviour for thousands of years, since it is clearly recorded in local Aboriginal legends concerning 'fire hawks'; only until now, white settlers have ignored the stories due to their implausibility.

Intelligent corvids

A 2016 report by the U.S. National Academy of Sciences has uncovered biological evidence to support advanced avian intelligence. Although their brains are a lot smaller than mammals, especially primates, this is obviously due to the overall diminutive size of the animals themselves. The brain mass to body mass ratio of some bird families is far larger than expected for an animal of that size, approximating that of the most intelligent mammals.

Although bird brains have a somewhat different structure to mammalian brains, the corresponding higher-functioning regions are both comparatively large and have a neuron density double that of primate equivalents. Therefore it appears corvids and some other birds have undergone parallel evolution that has maximised their cognition.

Birds are good at far more than just adapting to new conditions and environments, with the most social (as opposed to solitary) species leading the way in problem solving and abstract thinking. Here are few more examples that prove their cognition can go far beyond basic instinct:
  1. Self-recognition: Eurasian magpies (Pica pica) pass the mirror test, meaning they can recognise their reflection as themselves rather than as another member of their species. 
  2. Tool usage: various birds use twigs and cactus spines to extract insects, much as chimpanzees insert sticks into termite mounds.  
  3. Deception: Woodhouse's scrub jays (Aphelocoma woodhouseii) have been observed moving food caches to deceive onlookers and keep the food to themselves.
  4. Planning: Crows have used multi-step planning in tests to retrieve progressively longer sticks with which to reach food. This ability isn't new either, since the 1st century Roman polymath Pliny the Elder observed corvids undertaking similar behaviour to that described in Aesop's fable The Crow and the Pitcher.
  5. Exploiting artificial environments: The kea (Nestor notabilis), New Zealand's alpine parrot, has learnt to unzip rucksack pockets to obtain food. Despite being unlike anything in nature, some bird species understand man-made objects.
When I was a child, the term 'bird brain' was employed for derogatory purposes while 'talking' caged birds such as cockatiels, budgies and parakeets were thought of as just mimics without any understanding of what they were saying. This continuation of the Western tradition that humanity is the pinnacle of creation, far superior to all other lifeforms, is now under serious attack. Our prejudices have caused us to ignore the evidence right under our noses, but as per my post on animals that farm, we humans have very few unique traits left. Avian intelligence is undoubtedly different from ours, but perhaps less so than that of dolphins, whose watery environment means they are unlikely to ever be tool makers.

Another issue is that compared to say mammals, there is a far smaller variety of bird forms; even such specialised species as penguins, ostrich and kiwi don't stray far from the generic Aves design, meaning we tend to associate bird intelligence with the most ubiquitous - and comparatively slow-witted - urban species such as house sparrows and feral pigeons.

Beginning in the 1970s, researchers have explored the sometimes controversial notion that if the dinosaurs hadn't died out at the end of the Cretaceous, a small- to medium-sized carnivore such as Troodon would have eventually evolved into a reptile with human-level intelligence. Crows and their kind may not have a primate-sized brain, but these dinosaur descendants are evidently far superior to the dim stereotype we usually assign to them. They may be small, but clearly in this case, size doesn't seem to matter: our feathered friends are capable of far greater mental activity than their songs, squawks and screeches imply.