The great outdoors: getting children back to nature

With Christmas just around the corner it seems like a good time to look at the benefits of persuading children to swap their hi-tech electronic gadgets for the wonders of the great outdoors. The recently-slated Toys 'R' Us television advert that promotes their plastic junk at the expensive of a 'dull and boring' nature field trip only highlights a trend that as the rural population decreases, natural phenomena such as animals, weather and good, clean soil are deemed solely of interest to farmers. Some years ago, a London acquaintance who teaches English at a senior school reported that during a woodland walk - to explore nature poetry rather than nature itself - several of her female teenage students cried due to getting mud on their shoes. Just how distanced are children becoming from the world beyond their front door!

A sense of scale: humans against California redwoods

The last few decades have seen a move away from the outdoor adventures that typified my childhood: catching butterflies; building woodland dens; even exploring a derelict house. Instead, sitting in front of computers, TVs and games consoles has become prevalent, sometimes all at once. Not that this has gone unnoticed, as discussed in Richard Louv's best-selling Last Child in the Woods: Saving Our Children From Nature-Deficit Disorder. Although the phenomenon is common across the developed world, some countries fare better than others. For example, recent reports suggest New Zealand children (feeling a bit smug at this point) spend rather more time outdoors than their Australian, American or British counterparts. However, I'm sure there's room for improvement just about everywhere. There are many reasons behind the stay-at-home trend in addition to the obvious delights of being cosily tucked up with digital devices, but I believe it is more important to explore the effects this is having on our children:

1. The most obvious problem caused by a shortage of physical activity outdoors - which after all is free, compared to the indoor play centres often used for children's parties - is the lack of opportunity to develop coordination and motor skills beyond the mouse or joystick. Since we've experienced a generation-on-generation increase in the number of calories, sugar and fat in our diet, then clearly there should also be an increased amount of time spent burning this off. Obviously this hasn't happened, and various groups such as the International Association for the Study of Obesity have tracked the post-war growth in overweight children. If you haven't seen any of the resulting graphs, they make for troubled reading...
2. But it isn't just physical health that is affected. As a species, we are still coming to terms with urban living and the psychological problems of existence in near-identical cuboids in residential estates frequently bereft of greenery. The World Health Organization's definition of health includes mental well-being, which can incorporate the notion that regular playing outdoors confers benefits on children. I don't consider this as just referring to strenuous exercise: exploring the randomness of nature - from building sand castles to snowball fights - as well as the simple joys of experiencing weather at first hand, are also important. As if to confirm the problems that a lack of balance in indoor/outdoor activities can lead to, a work colleague recently informed me that his twenty-year-old son, a business degree student, was reduced to tears when he was unable to log on to his online gaming account for a few days. Oh, for an adequate sense of perspective!
3. Does the changing emphasis from natural to man-made environments mean are we losing a vital part of our humanity? Or are we seeing a new form of evolution for our species? The differences between nature and artifice are profound, from the seemingly (although only from our viewpoint) haphazardness of the former to the non-messy convenience sought as a given via the latter. Even a basic understanding of processes from food at its source might be useful as an educative tool to engender empathy for a planet we are so rapidly despoiling. It's very easy for children to overlook the natural wonders that still exist in even the most densely populated of nations when they primarily associate the rural environment with the exotic non-developed locales usually favoured by natural history documentary programme makers.
   
   Viewing nature at second hand is no substitute for - literally - getting your fingers dirty, whether it is planting flowers or foodstuffs, or simply scrabbling over muddy terrain. A 2010 survey conducted in the UK indicated that between one quarter and one half of British children lack basic knowledge concerning familiar native and introduced species such as horse chestnut trees and grey squirrels. Not that I'm convinced an appreciation of the facts might lead to more environmental awareness; after all, how many times has the 'closer to nature' sustainability of pre-industrial societies been shown to be a myth? But considering for example the enormous amount of bought food that is thrown away uneaten (perhaps reaching over 40% in the USA) surely any understanding of the complex cycles within the far from limitless ecosystem may engender some changes in attitude towards reduce, reuse and recycle? As evolutionary biologist Stephen Jay Gould once said, we will not fight to save what we do not love.
4. Further to the last point, knowledge as a safety net might come in handy, should the need arise. There's an old adage that even the most 'civilised' of societies is only nine missed meals away from anarchy, as the citizens of New Orleans learnt all too well in the wake of Hurricane Katrina in 2005. Considering just how much food manufacturers rely on oil for everything from transport to packaging (did you know North Sea prawns are flown on a 12,000 mile round trip to be cleaned and de-shelled?) it doesn't just have to be a natural disaster to generate such chaos. In October 2011 a leak in the Maui gas pipeline here in New Zealand led for a few days to empty bread shelves nationwide, highlighting the fragility of our infrastructure.
   
   A 2008 UK report concluded that British food retailers would exhaust their stocks in just three days in the event of a Hurricane Katrina-scale emergency, thus suggesting that those who follow chef and forager Hugh Fearnley-Whittingstall or adventurer/survivalist Bear Grylls will be the victors. I'm not suggesting children should be taught to distinguish edible from poisonous fungi but considering the potential dangers of even cultivated food crops (did you know that potatoes turning green may be a sign of the poison solanine?) any knowledge of foraging and food preparation may prove useful as well as fun.
5. Encouraging children to explore outside is as good a method as any to beget a new generation of biologists, ecologists and their ilk. Ironically, Toys 'R' Us list over 370 items in the science and discovery section of their online catalogue. Indeed, their advert includes several seconds' footage of a boy looking through the eyepiece of small reflecting telescope labelled 'science', although judging by the angle the telescope is pointing into the ground! As I've explored previously, doing practical science seems to be a far better way to introduce young children to the discipline than mere passive viewing or reading. It can also demonstrate that - with several exceptions such as high-energy physics - many of the basic structures of scientific procedure and knowledge are well within the grasp of non-scientists (perceptions are hard to shift: I recently heard a law graduate declare she wasn't sure she would be able to understand this blog, as science is of course 'very difficult'! )
   
   Each one of the above alone would be reason enough to encourage children to spend more time outside, but taken together they suggest that there is likely to be severe repercussions across many aspects of society if the adults of tomorrow don't get enough fresh air today. It may sound like something out of a Boys' Own Journal from the era of the British Empire, but there's something to be said for the simpler pleasures in life. I know I'd rather go for a forest walk or rock pooling than play Grand Theft Auto 5 any day...

Newton and Einstein: fundamental problems at the heart of science

As previously discussed, Arthur C. Clarke's First Law is as follows: "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." Now there have been many examples of prominent scientists who have been proved wrong but don't want to lose their pet idea - think astronomer Fred Hoyle and the Steady State Theory - or bizarrely negated their own hypothesis, such as natural selection's co-discoverer Alfred Russel Wallace and his supernatural explanation of the human mind.

But although with hindsight we can easily mock when pioneers have failed to capitalise on a theory that later proves canonical (assuming any theory except the second law of thermodynamics can ever be said to be the final word in the matter) there are some scientists who have followed profoundly unorthodox paths of thought. In fact, I would go so far as to as say that certain famous figures would find it almost impossible to maintain positions in major research institutes today. This might not matter if these were run-of-the-mill scientists, but I'm talking about two of the key notables of the discipline: Sir Isaac Newton and Albert Einstein.

The public perception of scientists has changed markedly over the past half century, from rational authority figures, via power-mad destroyers, to the uncertainties of today, when the often farcical arguments surrounding climate change have further undermined faith in scientific 'truth'. But the recognition of Newton and Einstein's achievements has never wavered, making them unassailable figures in the history of science. Indeed, if there were ever to be two undisputed champions of physics, or even for all of science - as chosen by contemporary scientists, let alone the public - this contrasting pair is likely to the among the most popular. Yet underneath their profound curiosity and dogged search for truth there are fundamental elements to their personal research that make the offbeat ideas of Wallace, Hoyle & co. appear mildly idiosyncratic.

1) Sir Isaac Newton
While some historians have tried to pass off Newton's non-scientific work as typical of his age, his writings on alchemy, eschatology and the general occult are at least as numerable as those on physics. Some of the more recent examinations of his work have suggested that without these pseudo-scientific studies, Newton would not have gained the mind-set required to generate the scientific corpus he is renowned for. Although he claimed to have no need for hypotheses or 'occult qualities', preferring to examine natural phenomena in order to gain understanding, much of Newton's surviving notes suggest the very opposite. Whether he was using numerology to research the date of the end of the world, or alchemy to search for the Philosopher's Stone, the real Newton was clearly a many-faceted man. This led economist (and owner of some of Newton's papers) John Maynard Keynes to label him "the last of the magicians". Indeed, key aspects of Newton's personality appear entirely in tune with pseudo-science.

It is well known that Newton was a secretive man, given to hiding his discoveries for decades and not wanting to share his theories. Part of this was due to his wish to avoid having to waste time with the less intelligent (i.e. just about everybody else) and partly to his fear of plagiarism, frequently experiencing conflicts with contemporary natural philosophers. To some extent this unwillingness to publish only exacerbated the issue, such as when Leibniz published his version of calculus some years after Newton had completed his unpublicised 'fluxions'.

Today, establishing scientific priority relies upon prompt publication, but Newton's modus operandi was much closer to the technique of the alchemist. Far from being a non-systematic forerunner of chemistry, alchemy was a subjective discipline, couched in metaphor and the lost wisdom of 'ancient' sages (who, after Newton's time, were frequently discovered to be early Medieval or Ptolemaic Egyptian frauds). The purity of the practitioner was deemed fundamental to success and various pseudoscientific 'influences' could prevent repeatability of results.

In addition, such knowledge as could be discovered was only to be shared between a few chosen adepts, not disseminated to a wide audience for further examination and discussion. In personality then, Newton was far more like the pre-Enlightenment alchemist than many of his contemporaries. He believed in a sense of his own destiny: that he had been chosen by God to undertake the sacred duty of decoding now-hidden patterns in the universe and history. When Descartes postulated a 'clockwork universe', Newton opposed it on the grounds that it had no place for a constantly intervening deity. And surprising as it may seem, in that respect he had a lot in common with Einstein.

2) Albert Einstein
Einstein was in many ways a much more down-to-earth (and fully rounded human being) than Newton. Whereas the latter frequently neglected such basic human activities as food and sleep, Einstein indulged in pipe tobacco and playing the violin (shades of Sherlock Holmes, indeed!) However, he was just as much a determined thinker when it came to solving fundamental riddles of nature. A good anecdote, possibly true, tells of how whilst searching for a makeshift tool to straighten a bent paperclip, Einstein came across a box of new paperclips. Yet rather than use one of the new ones per se, he shaped it into the tool required to fix the original paperclip. When questioned, he replied that once had started a task it was difficult for him to curtail it.

But one of the oft-quoted phrases surrounding him is that Einstein would have been better off spending his last two or three decades fishing, rather than pursuing a unified field theory. The reason for this is that despite being a pioneer in the quantum theory of light, he could not accept some of the concepts of quantum mechanics, in particular that it was a fundamental theory based on probability rather than simply a starting point for some underlying aspect of nature as yet unknown.

Even today there are only interpretations of quantum mechanics, not a completely known explanation of what is occurring. However, Einstein considered these as more akin to philosophy rather than science and that following for example the Copenhagen interpretation prevented deeper thought into the true reality. Unfortunately, the majority of physicists got on the quantum mechanics bandwagon, leaving Einstein and a few colleagues to try to find holes in such strange predictions as entanglement, known by Einstein under the unflattering term of "spooky action at a distance".

Although it was only some decades after his death that such phenomena were experimentally proven, Einstein insisted that the non-common sense aspects of quantum mechanics only showed their incompleteness. So what lay at the heart of his fundamental objections to the theory? After all, his creative brilliance had shown itself in his discovery of the mechanism behind Newtonian gravitation, no mean feat for so bizarre a theory. But his glorious originality came at a price: as with many other scientists and natural philosophers, from Johannes Kepler via Newton to James Clerk Maxwell, Einstein sought answers that were aesthetically pleasing. In effect, the desire for truth was driven by a search for beautiful patterns. Like Newton, there is the concept of wanting to understand the mind of God, regardless of how different the two men's concept of a deity was (in Einstein's case, looking for the secrets of the 'old one').

By believing that at the heart of reality there is a beautiful truth, did Einstein hamper his ability to come to terms with such ugly and unsatisfying concepts as the statistical nature of the sub-atomic world? In this respect he seems old-fashioned, even quaint, by the exacting standards required - at least theoretically - in contemporary research institutes. Critical thinking unhampered by aesthetic considerations has long been shown a myth when it comes to scientific insights, but did Einstein take the latter too far in his inability to accept the most important physics developed during the second half of his life? In some respects, his work after the mid-1920s is seemingly as anachronistic as Newton's pseudo-scientific interests.

As a result of even these minimal sketches, it is difficult to believe that Newton would ever have gained an important academic post if he were alive today, whilst Einstein, certainly in the latter half of his life would probably have been relegated to a minor research laboratory at best. So although they may be giants in the scientific pantheon, it is an irony that neither would have gained such acceptance by the establishment had they been alive today. If there's a moral to be drawn here, presumably it is that even great scientists are just as much a product of their time as any other human being, even if they occasionally see further than us intellectual dwarves.

School sci-tech fairs: saviours of the future?

It's frequently said that a picture is worth a thousand words, but could it be true that hands-on experiments are worth even more when it comes to engaging children in science? As the current Google / iPad / your-designation-of-choice generation is being bombarded from the egg onwards with immense amounts of audio-visual noise, how will they get the opportunity to learn that science can be both rewarding and comprehensible when textbooks seem so dull by comparison with their otherwise digitally-enhanced lives?

The infant school my daughters attend recently held a science and technology exhibition based on the curriculum studied during the last term. An associated open evening (colloquially labelled a 'Sci-tech fair') showed that parents too could delight in simple hands-on demonstrations as well as gain an appreciation of the science that their five- to eleven-year olds practice.

In addition to the experiments, both the long-term projects undertaken over several months and those carried out on the night, the entries for a science-themed photographic competition gave interesting insights into the mentality of pre-teens today. All the submissions included a brief explanatory statement and ranged from reportage to self-organised experimentation. One entry that I can only assume was entirely the child's own work especially caught my eye: a photograph of their pet dog standing in front of half a dozen identically-sized sheets of paper, on each of which was a same-sized mound of the dog's favourite food. The sheets of paper were each a different colour, the hypothesis being whether the dog's choice of food was influenced by the colour it was placed upon.  I say it was probably the child's work since I assume most adults know that dogs do not see as wide a variety of colours as humans, being largely restricted to the blues and yellows. But what a fantastic piece of work from a circa ten year old, nonetheless!

Apart from highlighting the enormous changes in science education - chiefly for the better, in my opinion - since my UK school days in the 1970s and 80s, the exhibition suggested that there is an innate wealth of enthusiasm at least for the practice of science, if not for the underlying theories.  If only more people could have access to such events, perhaps the notion that science largely consists of dry abstractions and higher mathematics would be dispelled. After all, if children in their first year of school can practice scientific methodology, from hypothesis via experimentation to conclusion, it can't be all that difficult, can it?

Each experiment in the sci-tech exhibition was beautifully described, following the structure of an aim or hypothesis, an experimental procedure, and then the results and conclusions; in effect, the fundamentals of the scientific method. Themes varied widely, from wave action to solar power (miniature cells being used to drive fans in scale model houses), animal husbandry to biological growth and decay. One of my favourite experiments involved the use of Mentos (mints, if you don't know the brand) to produce miniature geysers when added to various soft drinks. Much to the children's surprise the least favoured contender of the half dozen tried, Diet Coke, won outright, producing a rush of foam over five metres high. The reasons behind this result can be found on the Science Kids website, from which several of the term's projects were taken. The site looks to be a fantastic resource for both teachers and enthusiastic parents who want to the entire family pursue out-of-school science. I'll no doubt be exploring it in detail over the coming year...

Having dabbled in the world of commercially-available science-themed toys the description of how to make your own volcanic eruption experiment on the Science Kids site led my daughters and I to spend a happy Sunday afternoon creating red and yellow lava flows in the garden, courtesy of some familiar ingredients such as sodium bicarbonate and citric acid. They may not have learnt the exact nature of volcanism, but certainly understood something about creating chemical reactions.

Have fun making your own miniature volcano!

Although these hands-on procedures are considerably more interesting than the dull-as-dishwater investigations I undertook at senior school, the idea of children's participation in experiments is nothing new. The Royal Institution in London has been holding its annual Christmas Lecture series since 1825, with audience members frequently invited to aid the speaker. Although I've never attended myself, I remember viewing some of the televised lectures, with excited children aiding and abetting in the - at times - explosive demonstrations. The lecturers over the past few decades have included some of the great names in science popularisation, from Sir David Attenborough to Richard Dawkins, Carl Sagan to Marcus du Sautoy. Anyone care to bet how long it will be before Brian Cox does a series (if he can find time in his busy media schedule, that is)?

Getting to grips with the scientific method via experimental procedures is a great start for children: it may give them the confidence to think critically and question givens; after all, how many people - even students at top universities - still think the seasons are caused by solar proximity? If that's a bit of a tall order, perhaps hands-on experimenting might help children to appreciate that many scientific concepts are not divorced from everyday experience but with a little knowledge can be seen all around us.

Of course it's far more difficult to maintain interest in science during adolescence, but New Zealand secondary schools aren't left out thanks to the National School Science and Technology Awards and the National Institute of Water and Atmospheric Research (NIWA)-sponsored regional Science and Technology Fairs. It's one thing to give scholarships to scientifically-gifted - or at least keen - children, but quite another to offer a wider audience the opportunities these programmes offer. All in all, it's most encouraging. I even have the sneaky suspicion that had such inspiration been available when I was at school, I might have eschewed the arts for a career in a scientific discipline - at least one with minimal complex mathematics, that is!

Going, going, gone: how do you decide which endangered species are worth saving?

My elder daughter recently adopted a Sumatran tiger. Not literally of course, but an Auckland Zoo package bought as a birthday present, with the tiger chosen above the seven other species on offer because - at least according to my daughter's claim - it was the most endangered one. In fact, the estimate for the number of Sumatran tigers left in the wild varies between four hundred and seven hundred individuals, so the lack of accuracy is only countered by the fact that both extremes are so low. With countless other species similarly close to the edge, if not worse off, a key question has arisen in recent years: are some species more worthy of conserving than others?

Presumably the choice on offer in the zoo's Adopt an Animal programme is intended to increase awareness of the plight of these particular animals. But can there be many people at least in the developed world who are not aware of some of the ever-increasing roster of endangered species? Indeed, there are now widespread claims that we may be living through a mass extinction event, the sixth known. Interestingly, it's only been in the last few years that some sort of quantitative definition of a mass extinction has gained popularity over the earlier, somewhat vague ‘one hundred to a thousand times the background rate' designation, with a rapid (at least on a geological timescale) 75% loss of species deemed the minimum number. However, this figure appears somewhat arbitrary, yet is quoted in various general readership articles as the number of species currently headed for extinction! Evolutionary biologist Richard Dawkins has much to say on the subject of fundamentally meaningless statistics: for example, how is 74% so much less worthy of the term ‘mass extinction' than a mere one per cent more? Granted, there may just be too many unknowns for a consensus in expert opinion, but deciding on a one per cent cut-off line for such an event is surely creating a label for its own sake, useful for lazy journalists but little else.

The International Union for Conservation of Nature (IUCN) Red List makes for depressing reading, with around 7000 species listed between the three worst categories: critically endangered; extinct in the wild; and species that have recently become totally extinct. Even worse, it appears to be out of date, if the example of the Yangtze River dolphin is anything to go by. It appears on the first of these lists, as opposed to the third, where most experts agree it should now sit. The fact that no single organisation seems to have enough resources to compile definitive current data doesn't help. After all, if you cannot identify the species most in need, how do governments and agencies decide which ones to save (and, unfortunately, which to doom to near-future extinction)?

The environmental movement of the past half century has long capitalised on photogenic ‘poster' species such as whales, apes and the giant panda, which add a wow factor that has had the side-effect of concentrating much of the funding on them. This has regrettably deprived many less aesthetic species of publicity, and probably in the case of some species such as the Yangtze River dolphin, their existence.

There are strong arguments both for and against the continuation of this policy, although things have recently got slightly better as regards recognition for non-figurehead species. Late last year the BBC television series Dara O Briain's Science Club made a foray into this area with the question - covered at the programme's usual break-neck speed -  are pandas worth all the money spent on them? Palaeontologist Richard Fortey and zoologist Lucy Cooke presented arguments seemingly against the high level of resources accorded the giant panda. Indeed, the latter emphasised the decline of one third of amphibian species worldwide. The time has finally come to appreciate that non-cute species deserve much greater attention than hitherto gained. To this end, the decidedly unpleasing looks of the deep-sea blobfish have recently seen it voted World's Ugliest Animal in a concerted effort to improve awareness of all the species that are least likely to appear on any fundraising poster.

So considering how many species, including plants and fungi, are currently endangered, is it worth spending millions of dollars each year to preserve, say, giant pandas? After all, aren't the latter just a wee bit useless? With a diet that is 99% bamboo and a seeming lack of reproductive drive, couldn't they be viewed as an over-specialised, evolutionary dead end, doomed regardless of loss of habitat and poaching? However, it isn't as simple as that. The popular description isn't completely accurate, with panda libido in captivity seemingly less than in the wild, although admittedly females are apparently only able to conceive for a few days each year. Even so, is it worthwhile to spend millions on captive breeding programmes (involving artificial insemination) for these cute creatures when the money could be split amongst many other species?

Awww, cute...but is it worth it?

One of the key arguments in favour of figurehead species is that the publicity gained is then disseminated to other species in the same habitat, such as by keeping those environments as free of development as possible.  Preservation of entire ecosystems is a major element to the notion that for purely selfish reasons we should maintain as much biodiversity as possible. This is in order to preserve unique genomes that may one day prove useful in agriculture or as pharmaceuticals. After all, only about 5% of plant species have so far been studied for their medicinal properties, whilst the DNA of many species remains almost entirely unexamined. A good case can be seen with the Pacific yew, a conifer in severe decline that proved to be the source of an important chemotherapy drug. In a similar vein, loss of one species may cause the rise of another that is rather less neutral from a human viewpoint, whether it is an agricultural pest or a dangerous predator such as the aggressive Humboldt squid, which has largely superseded over-fished sharks around the Mexican Pacific coast.

So even without invoking a moral argument, there are plenty of good reasons why preserving as many types of organisms as possible may be important to our future.  Whether this can be achieved most efficiently via publicity-raising poster species is more difficult to ascertain. There are claims that we should support evolutionary-distinct species or those with a definitively viable breeding/cultivatable population, but this is hampered by the lack of detailed information mentioned above. For example, several population bottlenecks in the history of cheetahs have reduced their genetic diversity to such an extent that even a relatively comfortable population size - at least compared to some endangered species - is no guarantee of future salvation. In other words, the minimum viable population for a species is probably unique for each.

In addition, there aren't complete lists of members in each ecosystem for even relatively large creatures: it was only last month that the Olinguito, a Central American omnivorous mammal new to science, was formally described. With this lack of definitive information, it's little wonder there is a multitude of problems concerning even knowing where to begin conservation measures. Of course, spending funds on this sort of research, which has no immediate benefit to endangered species, would presumably take crucial funding away from vital preservation measures in the here and now. But since the research hasn't been done many factors remain little more than guestimates, thus creating a vicious circle as to which species require the most support.

This doesn't of course mean that dedicated ecologists are likely to be swayed from their labours of love by any amount of hard data. Whether the enormous efforts to save those species with miniscule populations is worthwhile in the long run remains to be seen. New Zealand's flightless parrot the kakapo, with less than one hundred breeding individuals left, is a prominent example. There are now so few that almost every bird has been named; but would it have been better to try saving multiple species with more likelihood of long-term survival? It's difficult to attempt objectivity when you are fighting for the survival of creatures that have been anthropomorphised even to the minimum level of naming them. Then again, it's often been the devotion of small groups of committed conservationists that pioneered the techniques now widespread, including the methods for publicising the plight of endangered species.

So it doesn't look like there are any easy answers in what has to be, if it is to succeed, a rapidly developing field. After all, it's only been a century since we stopped wiping out species for fun in the name of sport. Unlike the Higgs Bosun, some of the subjects involved in this area - the species themselves - aren't going to be hanging around for solutions at some indeterminate point in the future. As Gandhi put succinctly: "Earth provides enough to satisfy every man's needs, but not every man's greed." The problem is knowing where to begin on the mammoth task of fixing a planet-wide ecosystem. All I can say is good luck, because like it or not, we're all participants in this one!

Birds, bugs and butterflies: attracting nature to your garden

For many years I've tried to attract wildlife to my garden; perhaps there's something extremely relaxing about watching other components of the biosphere go about their business. Even the closest I lived to the heart of London, a largely overgrown garden provided a haven for all sorts of creatures from tiny wrens via boisterous squirrels to the odd, slightly mangy fox. Although I've discussed the behavioural changes seemingly present in urban animals I thought it would be worth exploring the pros and cons of attracting various critters to your garden.

As a child our family supported winter visitors, usually with bread crusts for birds and cow's milk - for some unknown reason - for hedgehogs. I've since learnt that the latter is a very poor choice as hedgehog food, so where the idea came from I don't know. Mind you, much bacon rind is probably too salty for birds, so I wonder how many animals we killed with our kindness! If you want to feed hedgehogs, cat and dog food is apparently among the suitable alternatives. Not that these days we put anything out for the hedgehogs that occasionally appear in our garden, often disappearing behind the wood pile at night when I'm out at the telescope (and startling me with their sudden snuffling). The reason isn't due to being anti-hedgehog, but the food would most likely attract other, less welcome rodents such as rats and mice.

Interestingly, hedgehogs are amongst the survivors brought to New Zealand by acclimatisation societies in the Nineteenth Century, along with many European bird species that also congregate in our garden: sparrows, blackbirds, starlings, song thrushes and various finches. As a side note, it would be interesting to tabulate these against the many imported species that didn't survive their first year in the New Zealand wild, such as robins and emus; clearly, there's some unknown adaption criteria going on here.

One problem I frequently faced in the UK but don't any more is the seemingly inexhaustible ingenuity of squirrels in getting to the content of bird feeders, as described in the post above. However, possums imported from Australia fulfil a similar, if nocturnal role in New Zealand, and are a major pest for numerous reasons. Again, keeping bird food for only birds is a primary consideration. Not that birds don't show cunning when it comes to getting at food: I remember visiting the Zealandia eco-sanctuary near Wellington many years ago and seeing the kaka bush parrot feeding from mini bins opened via foot pedal - that's the parrot's foot, not a human one.

Back to now. So why attract wild animals to your garden? Usually it's a two-way gain - humans watch the antics for minimal expenditure and the fauna get food, shelter or even a bath. It offers children a close up view of nature and the realisation that you don't have to go to zoos and wildlife parks for the experience: nature is all around us. It also introduces them to the diversity of the local biosphere as opposed to just the typical, ‘grand' fauna such as African savannah species or large sharks and rays that are kept in zoos and aquaria. To this end, the UK's Royal Society for the Protection of Birds (RSPB) organised the Big Wild Sleepout last weekend, the idea being to camp in your own garden or at an organised event in order to hear and possibly even see the nocturnal creatures we don't usually come into contact with. I only tend to be outside at night if I'm at the telescope, and must confess to frequently hearing the unmistakeable cry of the morepork, New Zealand's only native owl, but have yet to see one.

Talking of owls, birds are the obvious favourite to attract to your property, since it's easy for them to get around and escape from predators such as domestic cats. According to the RSPB over half of UK adults have fed garden birds. In recent years organisations have started to take advantage of all this previously unrecorded observational data by encouraging the public to submit sighting reports for collation. These projects range from observing familiar creatures such as butterflies and ladybirds, to tracking the growth of invasive species such as New Zealand stick insects in the UK's South West. The RSPB, which is a veteran of collecting such data, utilised a weekend in January this year for their Big Garden Birdwatch, the world's largest wildlife survey.

Following the State of Nature report released in May this year, it sounds like this sort of project hasn't come a moment too soon. The new assessment was compiled by twenty-five British wildlife organisations including the RSPB and makes for a sobering conclusion. It found that 60% of the 3,148 UK species under assessment have declined over the last half century, with slightly over 10% deemed under threat of extinction in the UK. It's impossible to know if the situation is similar in other nations, but such worrying statistics suggest that any help given by the public to aid biodiversity can only be for the better. But as per the hedgehogs and milk example, what other pitfalls are there to befriending fauna?

It is fairly widely known that common foodstuffs such as salted peanuts and desiccated coconut should not be given to birds, but how many people remember to soak white bread before putting it out so that it doesn't swell inside the animals' stomachs? Although you can buy purpose-made bird seed mixtures it is cheaper - and frequently better - if possible to grow a bird-friendly garden yourself. It depends on what species live locally, but some birds like open lawn for insect feeding, others prefer overgrown areas (the goldfinches in my garden are very keen on the latter) whilst other species prefer fruit or nectar direct from the tree or bush.

It isn't just birds either: as a child I remember a buddleia bush that attracted at least four species of butterfly whilst here in New Zealand a swan plant (a type of milkweed) plays host to dozens of monarch butterfly caterpillars over the summer. In addition, praying mantises lay their egg sacks on just about any vertical surface in our garden, masonry or timber, so spring sees a profusion of baby mantises heading for undergrowth. The trick is to keep them away from the swan plant; otherwise the caterpillars tend to disappear in their early stages at the expense of the mantises...

In contrast to planting your own, commercial ready-made food mixtures may have large carbon footprints or be grown in developing nations that could better use the land and effort for growing their own food. In addition, messy eaters will cause seeds to drop onto the ground where sterilised seeds can choke native growth and the non-sterilised ones germinate: we once even had a hemp plant that grew several metres in a month or so from some spilt seed!

Therefore having plants or garden layouts that provide food for birds can be as good as leaving out scraps or purpose-bought food. I suppose the main difference with the latter two is that you can place them where you like for ease of viewing. After all, watching birds eat is the primary attraction. Although you can buy bird feeders I prefer to make my own, with a variety of success rates depending on the design. The most popular to date has proved to be table hung from a cherry tree, with half apples spiked on nails attracting a regular stream of silvereyes. Here in New Zealand you can even feed nectar eaters such as tuis via an old wine bottle containing sugar solution.

One important issue is when you should feed wildlife. The best time of year is obviously winter, when natural foodstuffs are least available. As a general rule, it's probably best to stop feeding once chicks arrive, so that both they and their parents don't start relying on human support. However, in addition to providing food you can also create habitats suitable for assorted wildlife from mammals to invertebrates. As a boy I made a nesting box for a Cub Scout badge, but it was never inhabited, probably being located in too low and too busy a position for birds to consider safe. Today you can buy all sorts of homes and feeders suitable for different species and climates so there's no shortage of easy options. The RSPB recently started supplying a free guide to building animal homes in your garden, ranging from bird box to hedgehog shelter. I can even claim success with my homemade weta motel (current resident: one female tree weta), although it took some time to gain any inhabitants other than numerous, small cockroaches. Note the weta legs poking out of the hole below!

Most of these are generally great aids to wildlife and observing wildlife, although I find the idea of building small ponds not particularly attractive since any standing water in my gardens usually attracts biting insects to lay their eggs in it. When I lived in East London any empty plant pot that collected rainwater swarmed with wriggling mosquito larvae in next to no time. Not nice!

The one thing about this sort of amateur interaction with biology is that you can do as much or little as you like as quickly or slowly as you like, but you are bound to get some form of success. Having said that, there are still plenty of species I'd like to spot in my garden. I have a large pile of volcanic stone that would look good in a far corner of the back garden as a potential lizard home; friends down the road are lucky enough to have skinks and geckos around their grounds. I'm also ever hopeful of various sections of rotting timber serving as home to peripatus -  a.k.a. velvet worm - an ancient form of life that lies somewhere between worms and arthropods. Although I've definitely seen some small white things that might just possibly be very young ones...