There is more carbon stored in the soil than in the atmosphere. Probably more carbon there than in all life! Yet, how much do we know about it? Just as the world of gut flora has opened up recently, so more knowledge of soil is bursting on the scene. Important information.
Rather than write a summary of these stimulating broadcasts I invite you to go to the source material. So, when you are seeking stimulation head for this podcast.
Want to help the Earth? And your garden? Well, I’m following their advice: I’m adding as much organic matter to my soil as possible.
On land, they are everywhere – the teeming hordes of life. So, their biology and lifestyles must be a big evolutionary success. In the UK we have over 22 000 species of insects in all manner of shapes and sizes. They range from the inquisitive dragonflies, through the singing grasshoppers with world record legs, to the fluttering butterflies, annoying flies destined to die in inaccessible light fittings and helpful bees. We see them scurrying behind the loo (silverfish), biting our bodies (lice and fleas), gobbling our crops (aphids) and pollinating our runner beans (bumblebees). Thunderbugs might live in the soil, but seem to enjoy dying inside framed pictures, scale insects hardly ever move. Some insects walk on water (water scorpion), nibble us as we sleep (bed bugs) and delight us with their nocturnal visits (moths).
Like the spiders and crabs, insects have a chitin skeleton on their outside. Chitin, a tough polymer, glucose-amine chemical, is slightly flexible yet inhibits any increase in size. So, insects, to grow, need to regularly shed their outer chitin layer, grow rapidly in size by inflating themselves, and then the new outer layer hardens. Just as we attach muscles to our rigid bones, insects attach theirs to their exoskeleton. But, as the new external skeleton only slowly hardens they will be unable to move to escape predation when they grow.
While growth is an issue with a chitin shell, it is a versatile material and can be formed into strong, light and flexible wings, leg joints to allow movement and mouthparts to chomp food.
Water loss is always a problem for terrestrial animals and plants. Chitin can be made waterproof, yet that will inhibit breathing (gas exchange). So, many land insects have breathing holes (spiracles) in their outer layer that are linked to air-carrying tubes (trachea) that penetrate all the internal organs. (When dissecting a locust under water, to support delicate body organs, these silver-looking air-filled tubes are easily seen.) Breathing movements of a locust’s upper and lower abdomen are easily viewed as they concertina to pump air around their bodies.
Aquatic insects will often employ gills, linked to trachea, to exchange gases with the water. The gills are thin enough to allow gases to pass through them, although this is less efficient than having open spiracles.
Oxygen, from the moving air, is used in cellular respiration – the release of energy from organic materials. (Carbon dioxide is a waste product and will flow out via the trachea.) With small body volumes any heat generated is easily lost, so insects are mostly working at the same temperature as the local environment – they are said to be cold-blooded and will be less active on cool days or out of the sunshine. This makes them vulnerable to predation.
With breathing tubes, insect blood does not usually carry oxygen, so they have no red blood cells with haemoglobin. And, with a low metabolism, insects do not need blood to remain in high-pressure blood vessels – it often slowly flows in spaces between body cells. Nor does the blood carry waste chemicals to kidneys – they do not exist as separate organs, but waste is passed out by a tubular system.
I once kept locusts for laboratory experiments and was horrified how younger animals would eat the old animals while the latter was still alive. An extreme example of recycling. We also had some reptiles and amphibians which were fed on house crickets. Some of the small insects escaped, set up home in the heating and ventilation pipes and sang to us until they ran out of food. In a similar vein, our garter snakes went walk about in the open-plan laboratories to the consternation of the chemists! But, ending on a happy note, my then president of the Biology Society (Clare Doswell) was unhappy at introducing Marwell Zoo’s snakes at a meeting. I asked another student, unknown then to her, Chris Wilmarsh to aid her – they were later married.
Some facts about insect diversity.
Silverfish are Bristletails and are considered to be primitive insects. They lack wings and rush around our homes at night seeking out food – including paper, flakes of human skin and even shampoo.
I call Thrips, Thunder-bugs, and they annoy me considerably when digging on a hot day. Yuk! They occur in soil and tend to be sap-suckers when not attacking me for a drink. Some can cause considerable economic damage to crops.
There are 500 species of Bird Lice in the UK. I clean out our bird boxes each winter to reduce their impact, as some can over-winter and will await new nesting arrivals in the spring.
While I attempt to control lice numbers, I protect Lacewings. These delicate-looking insects have long green bodies and oval wings … and their young eat aphids / green and black flies. Amazingly, lacewing larvae lack a functioning anus, and so they store up their undigested food until they moult for the last time and gain an anus – finally relieving themselves of a comparative big dollop of poo expelled with anal gases! Lacewing females are said to lay around 300 eggs, with each larva consuming up to 10 000 aphids. If you grow vegetables – look after your lacewings. We find hibernating lacewings (and ladybirds) hiding in small cavities in the autumn. Many survive but need capturing to allow them to escape in the spring.
Wild lions in the UK? Yes, antlions. This is an organism not regularly spotted in Britain until the 1990s, when a pair were observed on an RSPB reserve in Suffolk. The mature animal resembles a dragonfly; however, the grub has an over-sized set of pincer-like jaws and settles at the bottom of a sandy conical pit. It conceals itself with only its jaws visible. Unwary insects, that might tumble into this sandy trap, do not survive the event. Even a rapid exit up the side is ineffective as the young antlion throws sand to stop the escape. Want to see one? Visit Wells-next-the-Sea in Norfolk or Minsmere in Suffolk.
I come across young caddisflies during riverfly sampling. There can be dozens in a capture, and they are mostly hidden away inside a sandy or vegetarian case stuck together with a glue. Other types are caseless but live underwater in webs or hidden between river gravel. When mature the adults look like moths with wings covered in short hairs rather than scales.
Grasshoppers were the sound of summer holidays when I was a kid … 60 years ago, sadly. Their high-pitched stridulations now mostly evade me, yet small ones enjoy our wild meadows all through July and August. Their slower-moving friends, the green crickets, can be spotted on potted plants all summer and happily pose for photographs.
The Emerald Damselflies are often called the ‘Spreadwings’, as they habitually perch with their wings open in a delta position. There are five European species, including the Common Emerald (Lestes spoons), Willow Emerald (Chalcolestes viridis), Scarce Emerald (Lestes dryas), Southern Emerald (Lestes barbarus) and Winter Damselfly (Sympecma fascia). The Common Emerald is our only native species, but in recent years, thanks to global warming, the Willow, Scarce and Southern species have been gradually colonising our shores.
The very first record of the Willow Emerald Damselfly was way back in 1979, when a dead one was found in East Sussex, near Pevensey. In 1992 an exuvia was discovered at Cliffe Marshes in Kent, and a female was found on the Suffolk coast in 2007. From this it is reasonable to assume that at least some small, if isolated, colonies were slowly being established in the South-East of the country.
The numbers reached a tipping point in 2009 when around 400 were reported from 35 sites in east Suffolk, north Essex and south Norfolk. Proof that they were breeding here was that among these were a number of teneral, or immature, individuals which must have hatched out in this country. The damselfly rapidly began to increase its territory. By 2012 it was well established in North Kent, and by 2015 had colonised Cambridgeshire, Herefordshire and West Sussex. More recently it was discovered in Yateley in the North-East corner of Hampshire. In Andover, as 2020 came and went, our eyes were out and searching, but none were found and there were no sightings any closer.
This was about to change thanks to a local birder, by the name of Brian Cartwright, whose habitual haunt is the local Anton Lake. He frequently sends photos he has taken through to me, particularly of Odonata. On the 14th September, he sent through a dozen or so photos and the set included this:
Needless to say this invoked much excitement, but despite regularly searching of the area of the Lake where he had found it, no further sightings were made. However, as this year’s season approached the hunt was well and truly on.
Willow Emeralds are late emergers. They are a species of standing water, of ponds and lakes, ideally with healthy reed beds. In late summer and early autumn the females inject their eggs into the bark of the slender, young twigs of trees that reach out to overhang the water. The insect is not as fussy as its name implies and will use a variety trees and bushes, including Alder, Ash, Elder, Birch and even Hawthorn, but its preference for Willow very obviously gives the common name of the insect. When laid the eggs do not immediately hatch, instead entering a period of arrested development known as diapause. It is important that they are not laid too early otherwise the warm weather of late summer will stop this happening and they will hatch. If they do the nymphs are vulnerable to the coldness of the water of the lake or pond over winter. There is also the very real possibility that the protolarva would fall onto bare ground revealed by the water of lake or pond drying up during the summer. Come spring the eggs hatch and the protolarvae drop into the water. Here they will undertake their first moult and start eating, hunting voraciously, and growing rapidly to emerge as adults around 3 months later. They often fly away from their birthing pond or lake, to become sexually mature, before returning to ensure the next generation. Their normal flight period is from early August through to late September, or even early October.
And so it was that on August 5th I was wandering along the bank of a small private lake, set just away from the River Anton, when this landed beside me:
This is another male Willow Emerald, and the pose I’ve caught makes the delta position of the wings very clear. Our rather more native Common Emerald rests with the wings in the same delta position, as mentioned it is also a ‘Spreadwing’ species, but the two are easily told apart. Here is a male Common Emerald for comparison:
The first difference, obviously not evident in the photographs but very much in the flesh, is that the Willow Emerald is a larger insect. However, the first characteristic that will catch the eye is the colour of the pterostigma. These are the spots towards the end of the wings. Notice that on the Common Emerald they are very dark, almost black, while on the Willow Emerald they are a pale buff, almost a cream. You will also notice there is a lot of blue pruinescence on the Common while there is none on the Willow. Another identifier, although rather less obvious and requiring a decent photo to spot, is that, viewed from the side, on the Willow Emerald the pale underside colour extends a ‘spur’ into the darker colour above:
Willow Emeralds exhibit rather different behaviour to other Damselflies. Most Damselflies are fairly sociable, often being present in large numbers together. Even when preferring to keep their distance from others there is rarely any confrontation. Willows, on the other hand, act much more like the Skimmer Dragonflies, with males selecting a territory. Here they will perch, often on the end of a prominent twig or branch, and drive away other males even as they search for a female.
Over the next few days I searched the other lakes around Andover for the species. I was lucky enough to see a mating pair at Charlton Lake, although not so lucky as to be able to get a photograph of them. On the 2nd of September, I saw my first one at Rooksbury and, on the same day, Brian sent through a photograph of a mating pair he had managed to capture at Anton:
Notice how much stubbier and blockier the female is in comparison to the rather slim male. This meant that I had now established that the species was present on all four of Andover’s local lakes. Unfortunately, I still hadn’t managed to get a shot of a female, the only ones I’d seen being involved in mating, either in tandem or in copula. This species usually oviposits when the male and female are linked up in tandem. At this point, it seemed that numbers were still good and I held out hope for finding and photographing a female myself, but as the end of September drew ever closer I realised that wish might not be granted.
Today, 30th September, I have finally admitted defeat. It’s possible that I might still come across the elusive female I seek, the species can be found into October, but there is a chill in the air and I don’t think I’m going to be that lucky … this year. But …. next year … when numbers should be higher …
Evolution is powerful. If you fail to fit in, something else will take your place, and freshwater is today only filled with the fittest of plants. Yet, those plants originated as marine organisms that migrated onto the then uncolonized land. Here the conditions were very different, and evolution forced them to support themselves, to cope with a drying atmosphere and obtain carbon dioxide, water, minerals needed for their biochemistry and sunlight energy. It took a long time … with steps via the liverworts, mosses, horsetails and ferns before the dominant flowering plants emerged.
Somewhere along this journey some species changed direction and moved back into water – fresh water. For, we are told, they did not arrive directly from a marine environment.
So, what makes freshwater Angiosperms so special?
These hydromorphs come in all shapes and sizes but have one feature in common – their roots and stems, and possibly other structures, are full of holes. A tissue type called aerenchyma. Air spaces are supported by the thinnest of internal ribs of small, water-filled cells. These gaps allow easier gas flows from the aerial parts down to the oxygen-needing roots, which sit in oxygen-deficient, anaerobic mud. The air provides buoyancy, so keeping the photosynthetic parts nearer the light.
A trick to show this aerenchyma is easy. Collect some aquatic plant, cut its flimsy stem at an angle and weigh it upside-down in a jam jar. When exposed to light the photosynthetic oxygen moves around the stem and will emerge as bubbles. You could collect these gases and, using a glowing splint of wood, by plunging it into the gas it will relight – a sure sign of oxygen. A similar experiment with a land plant will show little or no emerging gas.
Some plants evolved to dwell on the water surface. Duckweeds are a good example. They appear to have only one or a few airy, floating, leaves and trailing, fine roots. However, the most determined of you, in June or July, will collect some and see minute flowers. (Now, there is a challenge for you!)
What to do if you are totally emerged? There are no bees available to transport the pollen to a stigma. So, the Hornwort (Ceratophyllum demersum) bears small underwater flowers whose anthers detach and float to the surface, they burst open (dehisce) releasing heavy pollen that sinks down to pollinate receptive stigmas. Clever! The Canadian Pondweed, an introduced plant that is only female, has long, fine flower stems to thrust its flowers, in late summer, onto the water’s surface.
Plants rooted in the mud, yet with emergent leaves can suffer badly in a cold winter. The Water Soldier (Stratiotes aloides) lays down heavy calcium deposits in autumn, increasing its density – so it sinks to a less-stressful environment. It reverses the process in spring and again floats – an then produces its evil-smelling flowers that are fly pollinated.
Marestail, Hippuris vulgaris, is an emergent plant that many think is a horsetail. (Not so, as small green flowers can be spotted by those brave enough to wade out to view them in summer.) Here, the plant’s internal structures are quite different in the aerial and aquatic parts. Long, thin, transparent, underwater leaves are replaced by short, thick and stiff ones with both a thick, waterproof, cuticle and stomata. The plant is a great example of the requirements for both environments.
We have lilies in our eco-pond. Some are rooted in the mud, others free-floating with delicious small yellow flowers. Their ‘Big Brother’ lives in the Amazon with leaves 2m across and covered in vicious spines to attempt to eliminate consumption by fish. Our version is much tamer but with stomata only on its upper leaf surfaces.
When in Central East Africa I encountered Water Hyacinth. This, like Canadian Pondweed, is an introduced exotic that is toxic to local wildlife and has seized the opportunity to cover vast tracts of water. It blocks waterways, shades out underwater plants, increases transpiration and generates an environment that encourages luxuriant mosquito populations and plentiful bilharzia-carrying snails. Be careful what you put in your eco-pond … my Canadian Pondweed is a menace but controllable.
We set out to make our 1.25-acre garden wildlife friendly. It was one of the first in the UK to ‘hit the media’ – and that was 30 years ago, and it is 20 years since being on the BBC, The Garden magazine and other major outlets. We feel we were part of the original push towards a more wildlife-relaxed style that has taken off big time here. And, yes, we still consider it a correct decision.
The plot has relaxed shrub and herbaceous borders, many substantial trees, and meadows that are managed in different ways. Wild hedges border the garden and have been planted with natives and allowed to grow to flowering and fruiting, and seldom trimmed. A pond, almost dry now, has no fish and so is rich invertebrate biodiversity … although the young dragonflies and newts vacuum up our tadpoles.
With comparatively small meadows it is a challenge to suit the management to all life. So, we have concentrated on floral diversity, hoping that will lead to invertebrate richness. However, the meadows’ bareness in autumn may kill off some late-developing butterfly larvae and the seed heads are not available to the birds.
Our main lawn is not cut in April or May and is left as long as possible into June to allow the orchids to bloom. Wandering paths give it a sculptural feel and ensure visitors understand that growth is not just through neglect! It is a positive move, and the stunning floral display shows that. But, by June the sequence of: snowdrops, crocuses, wild daffodils, cowslips and primroses, and the final fling of bulbous buttercups with meadow saxifrage and orchids is over, and the area needs trimming for the grandchildren to access. We call this our Spring Meadow sequence.
Beyond is the Summer Meadow that is uncut until late summer, but in phases, and not at one go. The grasses grow taller here and ragwort, scabious and knapweeds are frequent. Without the June cut the semi-parasitic yellow rattle, often called the ‘meadow maker’, thrives and controls excessive grass growth until July, when the rattle seeds and dies. Crickets and grasshoppers enjoy this area, and marjoram’s nectar keeps the moths, butterflies and other invertebrates content.
However, our insect diversity is declining. We are a small plot surrounded by an over-grazed horse paddock, farmland and Harewood Forest. Bad weather years hit butterfly diversity and there are fewer opportunities for recolonisations.
We have a good range of mammals around. Deer sometimes penetrate the perimeter, foxes, stoats and weasels are occasional visitors, moles enjoy both the meadows and flower borders, long and short-tailed voles cling-on in the hedges, while our yellow-necked and woodmice visit the nut feeders. We currently appear to have three generations of dormice in the hedge, with the youngsters showing frustration in how to access the nuts initially. As I have said previously, I now think of the dormice as acting like small squirrels rather than mice. They are amazingly quick, agile and jump readily. Cut creatures!
We do have bats, but getting them to species level unconvinces me. But there are a minimum of three species from their feeding sounds and techniques.
Predatory birds are around much of the time. We have buzzards, red kites, kestrels and sparrow hawks. I have spotted a goshawk twice.
The swallows are still with us, hawking for flies, yet they will soon head south.
Now the meadows are fully cut, and the last flowers are offering pollen and nectar to flying insects. The compost bins are full and digesting the material that will be spread as a mulch in spring, while the pond had been dredged and excessive herbage removed. The garden is settling down, yet winter-green orchids such as pyramidals will soon be showing their leaves … a sign of things to come.
For those of us living in northwest Hampshire we are used to a chalky landscape cut through by clear rivers and streams. The river valleys are lush, alkaline and covered in the remains of C17, C18 and C19 water meadows (see article). So, my ecology group opted to visit South Dorset with its areas of dry sandy-gravelly soils yielding heathlands with distinctly different ecology.
The geology of the area means that the top layers of ‘soil’ are seldom soil at all. The water drains so easily that the plants live mostly in ultra-dry conditions and are xerophytes – plants with small, tough leaves and growing mostly to just centimetres in height. With their accumulation of energy, and so organic matter, so limited their substrate contains precious little humus and nutrient recycling is low. The open heaths are dominated by ling (Calluna vulgaris) with the driest places showing bell heather (Erica cinerea). The Dorset heath also occurs here (Erica cilliaris).
The odd thing is that rainfall, over the centuries, has washed many nutrients out of the top sandy layers and the iron is deposited as a water-impermeable iron pan … resulting in the lower areas being very wet indeed. Here, cross-leaved heath (Erica tetralix) dominates, and the environment is acidic.
Even if organic matter accumulates on the open heath it forms a thin layer and no subsoil develops.
With dry soils and few nutrients growth rates are minimal and food chains short and unusual. When I live-trapped for small mammals in these areas I found none. The food chain is mainly ling > small insects > lizards > smooth snake. Even adders struggle here and prefer to dwell around the local RSPB farm. Predatory birds have little to pluck from the ground and stick to the wooded zones and coastal marshes.
Gorse (Ulex europaeus) is a spiny plant that can dominate if grazing or burning does not occur. Growing to a couple of metres in height and with yellow blooms that, to me, have the aroma of coconut it provides above-ground nesting sites. At ground level, a more amenable plant is the dwarf gorse (Ulex minor) found on thinner soils and in more open locations.
The star of the area, and a challenge to locate, is dodder (Cuscuta epithymum) – a parasitic climber without any hint of chlorophyll. It has thread-like red stems, no roots at maturity, and leaves reduced to useless scales. For nutrition it latches on to ling, extracting both water and organic materials. In September 2022, its white-pink flowers had gone, and its stems had been largely desiccated by the hot summer.
Adjacent to Coombe Heath is a small wetland whose pH surprised me in being near neutral and not around pH 4 as I had predicted. As it was not acidic it had many water invertebrates, including carnivorous water boatmen. The special organism was, however, raft spiders that patrol the water’s edges and consume small insects. Regrettably, they had seen us coming and had hidden.
However, the Arne RSPB nature reserve where we were based has one area to the east, that has sufficient soil quality for fields and woodland to have been developed. Here the ecology is quite different with oak, birch, sweet chestnut and Scots pine. It is probably an area long ago reclaimed from Poole Harbour and it has river deposits on its surface.
With better soils allowing a range of deciduous trees and shrubs to develop, and areas of modest farmland, the animal life is more diverse. We spotted small herds of (non-native) sika deer, grey squirrels and plenty of signs of rabbits.
Sika deer are Asian, yet thrive here, so need human control and their population is (sensibly) well down on previous years.
With the deer’s rut fast approaching, at least one male was in close consort with one herd of females, another building up its strength by feeding on the salt marsh.
Surrounding the area to the north, south and east are rivers and Poole Harbour. It is tidal and the exposed muddy fringes are rich in both algae (hence organic food) and invertebrates and they draw in predators. Waders, ducks and gulls are common. Egrets stalk the narrow inlets, terns surface dive for fish and there is an osprey nest – although its single chick was caught and killed by a goshawk.
In the distance, the view incorporates the chalk hillsides near Corfe and Corfe Castle itself.
Arne RSPB is part of The Purbeck Heaths National Nature Reserve that stretches from Wareham in the northwest down to Studland on the southeast coast. It comprises one of England’s largest wildlife-protected zone. Most of the fences have been removed to allow free movement of larger organisms and some semi-domesticated pigs have been released to break up some soils and to encourage annual plants to again flourish.
The name ‘heath’ is given to lowland areas dominated by heathers, more upland and wetter places are called moors. Heaths are an internationally very rare habitat and their wildlife is often endangered.
The place is not without serious challenges. My ecology group’s second day had to be scrapped as human activity (a BBQ) had burned out our sand dune study site and human pressure is strong, especially along the coast. Some newly acquired land had previously carried exotic conifers. While the large trees had been removed, a strong seed base remains and thousands of seedlings will need removal – a daunting task for volunteers.
Southern England, and much of Western Europe are having a hotter and drier summer than average. Rainfall for the year is well down and, with river levels dropping, local hosepipe and sprinkler bans are in place.
Our water is pumped out of our underlying chalk bedrock and, when extraction exceeds input, the springs dry and river flow decreases or stops. Water is a limited vital resource and costs – it needs pumping, possibly cleaning and treating with chlorine before we receive it.
I sample the local chalk river, the River Anton (a tributary of the famous River Test), for the river flies and other fauna to assess pollution and biodiversity levels. This data eventually adds to the mass of similar results across the UK that inform the Environment Agency of water issues. This activity is an example of Citizen Science, as we are semi-trained volunteers.
The River Anton is now down to 1/3 of its usual depth and drying up higher up its course. With flow rates down, water temperature increasing and depth impacting on fish and water mammals, it is a worry.
However, some self-centred individuals ignore the hosepipe-use ban. I have witnessed one who was sprayer-watering grass 24/7, only moving to overnight watering after a complaint. Now the water is switched on when it was dark and off when they appear in the morning. Eight hours – 1000s of litres of scarce water – on one small patch of grass. In my view, dreadful waste and contrary to the existing ban.
Our local water supplier, Southern Water, has been slow to react to my complaint, so I have resorted to alerting the local press – hence the headline. (They must have been desperate for copy!) Finally, with my complaints also going to a national water regulator, Southern Water has been forced to react.
So, I urge everyone to respond to environmental issues and fight for ‘what is right’.
The name John Lewis is synonymous with quality department stores in the UK. It has a subsidiary, Waitrose, that is its supermarket chain. However, unlike many similar companies, JL has other sides. It owns arable, dairy, mushroom and apple farms in Hampshire and its vineyards produce quality wines. Yet, there is more: it owns and manages a long section of the famous River Test, adjacent nature reserves, the Longstock Water Garden and the adjacent nursery and restaurant.
Longstock is a few miles south of Andover and north of Stockbridge, and the water garden sits on river gravels and alluvial soils. The site has been developed over around 100 years from gravel diggings and is beautifully maintained.
I will allow the photographs to tell the story of the place and its vegetation, yet it has its difficulties. The narrow access stream carries small amounts of silt which slowly fills up the waterways. So, occasionally the accumulated debris needs pumping out – not a mean task!
In 1998 our family spent some time exploring Kenya for the first time. Perhaps one of the most interesting journeys was to the far north-east of the country, to Lake Turkana, beyond the lands of the Samburu Tribe. It is remote, very remote and we drove for many hours seeing no other vehicles, and sometimes not even seeing the road – we just headed in the right direction across volcanic larva fields.
We had first spotted the area from a plane heading to Malawi. We had been in the cockpit when Annette asked, “What’s that lake?” The friendly pilot searched for an ancient atlas and responded, “Lake Rudolf”, as it was once called. Now it is now called Lake Turkana and is proudly the world capital for Nile crocodiles – over 14 000. , It is the world’s largest permanent desert lake and is semi-saline with no outlet to the sea and 1cm of evaporation daily. It, indeed, has had a third name, The Jade Sea. (See the book at the end.)
The rocks in the surrounding area are predominantly volcanic. The Central Island reserve is an active volcano, emitting vapour. Outcrops and rocky shores are found on the east and south shores of the lake, while dunes, spits and flats are on the west and north, at a lower elevation. It is very dry and conventional agriculture is utterly impossible.
On-shore and off-shore winds can be extremely strong, as the lake warms and cools more slowly than the land. Sudden, violent storms are frequent. Three rivers (the Omo, Turkwel and Kerio) flow into the lake, but lacking outflow, its only water loss is by evaporation. The lake’s volume and dimensions are variable. For example, its level fell by 10 m (33 ft) between 1975 and 1993. However, it now has increased in size by 10% and many surrounding areas have been flooded, with villages being isolated or destroyed.
A new dam is in prospect in neighbouring Sudan which will divert water to irrigation schemes. This will impact a tragically poor community even futher.
Our journey to Turkana, from Nairobi, took several days, first stopping at lake Baringo before hitting the wild, remote northern Kenyan country.
Maralal was dry, even though we arrived in August. The town was lively with proud and aloof people dressed often in red, stripped clothes. Most locals were reluctant to be photographed, but some Kenyan shillings turn a few peoples’ minds.
With desert-like vegetaion the countryside felt unproductive, although the acacia trees had fearful spines that even penetrated my shoes and the Landcruiser’s tyres. Ostriches, Grant’s gazelles and zebra were around, as were large bateleur eagles.
Eventually, the ‘road’ defeated the vehicle. Three attempts to drive up the stream bed’s side failed, until a winch (and shedding the human cargo) supplied enough pull to reach the top. At times the Landcruiser travelled at about 1kph for long periods.
Despite the remoteness, people were around. Camel herders and tribally-dressed men could be spotted sitting under bushes. Of volcanic cones there were dozens, with a count of 50 in one location.
As one could reasonably expect, camping was basic and had its interesting side. One night, at Baringo, we had hippos trotting and grunting past our tents, and near South Horr we had a fully dressed Samburu warrior, complete with spear, squatting outside the tent all night for our protection. (No loo trips that night!) The long-drop loos here were yet another experience, with their embedded wildlife interesting and very mobile. But, at our lake venue we had our own huts, complete with a 30cm lip in the entrance. Why? To stop Nile crocodiles wandering inside.
At our lakeside camp, we swam inside a crocodile-proof enclosure but other activity was impossible for us due to the heat.
Along the lake shore we encountered nomadic herdsmen with flocks of camels and goats, plus a few donkeys and, surprisingly, sheep.
A further issue on our exploration was that the Samburu and Rendille tribes were killing each other, each currently accusing the other of cattle rustling. This stopped us visiting the main settlement of Loyangalani.
We were picked up from our lake campsite and taken to the El Molo village. Spotting cormorants, shags, pelicans, white and goliath herons, Egyptian geese, plovers and African skimmers from the powered boat. Distant views were had of timid crocodiles, which are locally hunted for food. Around the settlement were grey-headed gulls, kori bustards, sand grouse and various hornbills.
The photographs give a feel for the village, but not the overriding smell of fish and a ground covered in fish scales. Inside, the hunts were basic with a bed, three stones to contain a wood fire (wood collected many kilometres away and carried back by the women) and a metal cooking pot. Clothes and other resources were virtually absent. There was a communally-owned maize grinding machine; the maize being donated by the USA.
Despite their basic construction, with a lack of rainfall the locals told us the buildings were long-lasting.
The tribal dead were ‘buried’ by placing stones over the body as digging was impossible.
The El Molo live in an impossibly remote location and their population was mainly found in two villages of 150 and 70 residents. The whole tribe is no greater than 1100, and its integrity is being diluted by marriage and its unique language is nearly extinct.
My Lonely Planet says of the Jade Sea – ‘Top the ridge here and therein is in front of you – The Jade Sea. It’s a breathtaking sight – vast and yet apparently totally barren. Youll see nothing living here except a few brave, stunted thorn trees. When you reach the lake shore, you’ll know why – it’s a soda lake and, at this end, highly saline.’ Of the El Molo village there is no mention.
See: Journey to the Jade Sea, by John Hillaby. This is only available second-hand and is historic, but recommended.
There is an article about the El Molo in the Guardian. See website for 1st February 2022/
Annette and I embarked on a two-week exploration of the coastline at the start of June. Our first stop was just west of Newport at the Tredegar House caravan site. This allowed easy access to The Newport Wetlands which are partly managed by the RSPB and dominated by present and past electricity generation.
As is often the situation in the UK, the site is reclaimed from industry. Any elevated sites (and there are many) have been built up with coal ash from the adjacent, but defunct, coal-fired power station. Even the wetland ponds were once slurry pits; despite that, they hold some interesting wildlife.
Reedbeds, grassy wetlands and estuarine habitats are here. There are 16 species of dragonfly, rare bees and an abundance of butterfly and day-flying moths, while stoats and weasels are often encountered … but not for us. Water shrews are here, too, but are mostly nocturnal and always challenging to spot.
The RSPB staff mainly deal with school groups, yet are a fund of knowledge and we were pointed to a huge heap of reed-cuttings just 100m from the entrance. Several large grass snakes were basking there despite the cool summer conditions. Most likely, the pile would serve as an incubation pile for their leathery eggs. Yet not all the snakes have it so easy, one went, with considerable difficulty, down the throat of a grey heron!
With only one hide and limited access to the waterways, the animal wildlife has the place to itself. With it being summer, waterfowl were in low numbers, but grebes, moorhens and mute swans were easily seen. A single male marsh harrier quartered the extensive reedbeds, and buntings and warblers played us their songs. Bearded tits are common here.
Even before we passed the entrance there were orchids on display: bee and southern marsh orchids being common. Overall, there are five orchid species here.
Overall, an interesting location but hardly worth a full journey in summer. As a local excursion, it offers plenty.
We headed west.
The Gower Peninsular is spectacular scenery. It is a chunk of limestone dumped onto the bottom of Wales, just west of Swansea. About 70 square miles (180 km2) in area, Gower is known for its coastline, popular with walkers and outdoor enthusiasts, especially surfers. It was the UK’s first AONB (Area of Outstanding Natural Beauty), which gives it mild planning protection.
The north-coast is estuarine and is dominated by salt marsh and cockle beds, with plant-rich sand dunes in the south-west. The south coast is a delightful combination of rocky bays, sandy beaches and sand dunes. The east is a conurbation and we failed to sample it.
Inland are stone-walled small fields, some dating back to Medieval times, and open common land. Stone-built castles abound here.
Woodland is limited, and those open are infested with dog walkers who seem unable to control their barking and unpleasant hounds. Grab a heavy stick if you wish … we were attacked by three dogs and were shaken by the experience.
The best wildlife locations: Cym Ivy sand dunes near Llanmadoc (Britannia Inn for an evening meal is worth exploring) – look out for marsh helleborines in the wet areas and sea holly near the coast; Worms Head for nesting seabirds, kestrels and coughs. Oxwich National Nature Reserve offers yellow rattle and several orchids, plus a healthy adder population. Oxwich Wood, just south of the village, is a woodland I’d love to own. It is rich in ferns and its slope gives it a challenging format.
For a spectacular hay meadow visit the wonderful Welsh Botanic Gardens. We encountered thousands of greater butterfly, spotted and southern marsh orchids. A stunning site overall as they have incorporated wild planting whenever possible. A real must-visit in June.
However, the Llanelli Wetlands, Wildfowl and Wetlands Organisation, was too much a smelly zoo for us. Perhaps it would offer more in winter when the migration of northern bird species would add some attraction.
There are three basic feather types: 1) The PRIMARY FEATHERS which provide the left in flying, 2) CONTOUR FEATHERS that often have a more downy lower part and 3) DOWN FEATHERS that are for controlling body temperature – the bird’s underwear!
Down feathers can be plucked in birds such as the wider to provide insulation within the nest. Some of these feathers break off at the tip to yield a fine powder – especially in herons.
Some parts of a bird’s body may lack feathers. The brood pouch being an example.
Obviously, feathers are not randomly spread over a bird’s body. Each type grows in specific locations.
There are feather types intermediate between contour and down feathers.
Each feather can be moved separately by muscles within the skin, even though the feather is dead at maturity.
Feathers are unique to birds, each consisting of a tapering shaft (Rachis) bearing a flexible vane on each side. The short basal part of the feather (Calamus) is round in section and is almost hollow. During growth, it has a blood supply but that is sealed off at maturity, leaving a non-metabolising structure. It is dead.
Feather numbers vary from just under 1000 in some hummingbirds, to over 25 000 in wintering swans. In most birds the feathers contribute 15 to 20% body weight.
Feathers often change colour by abrasion, with the ends being rubbed off during use. The change from winter to summer plumage is said to be often achieved in this way rather than growing new feathers which would be resource demanding.
Feather colours are produced by a combination of relatively few pigments – melanins, which the bird manufactures, and carotenoids giving the yellows and reds. The latter are from the diet. Of course, flamingoes lose their pink colour when deprived of their natural placktonic diet.
Additional colours by microscopic prisms of wax (sort of!) which refract light and generate the colours on birds such as the UK kingfisher.
Birds usually moult their feathers once a year. Golden eagles keep some of their feathers for two years.
The wish bone is equivalent to our collar bones, the clavicle.
Penguins swim with their wings, so have a keel.
Having lost their fore-limbs to flight evolution has given birds many more neck bones – 11 to 25. This gives them a flexible neck capable of reaching most parts of the body.
Remember: you can access any of over 150 articles from ARTICLES above,
David Beeson, May 2022
While nearly everyone you meet on a nature exploration can identify most of the birds they encounter, few know much about how they work. This article is an introduction to some aspects of their physiology.
For those who require more detail, you should obtain: Handbook of Bird Biology (Cornell Lab of Ornithology) and see the chapter on Physiology.
Supplying oxygen to flight muscles
Flight is a high energy-demanding activity. Birds use the energy in wind to reduce this requirement, yet even getting off the ground can be difficult … as I found out attempting the high jump at school!
Human ventilation works by drawing oxygen-rich air into the lungs using the diaphragm and inter-rib muscles. This air goes into the small sac-like alveoli of the lungs, where oxygen is exchanged for carbon dioxide. Expiration expells that air back into the environment. Of the 20% oxygen in the incoming air only around 4% is taken up by the lungs; an efficiency of around 20%. Now, when I achieved that percentage in examinations I was not proud! This method is insufficient for a high-energy demand such as flight.
The human gas exchange system is in Diagram B below. (Blue is air, red blood.)
In A, the bird lung, there is no mixing of input and output gases, and that is much more efficient, so much more suited to an aerial life-style.
Birds avoid the mixing problem by moving air through their lungs in one direction via a series of 7 to 9 air sacs, connected by loopy tubes. Birds take oxygen into their body tissues when they breathe in and when they breathe out. So, for every bird breath, humans would need to take two. Effectively, air flows continuously through a bird’s lungs, while in the human it pulsates.
Birds do not have a diaphragm and the lungs do not flex as in humans. Instead, the air sacs change volume and act as bellows, and these sacs are spread around the body. The whole body cavity, not just the pleural (lung) cavity, changes in volume during breathing.
Bird lungs and air sacs occupy twice the comparative body volume in birds to humans, while their lung is smaller. The reasons are clear: flying is very oxygen demanding, they have a higher body temperature (42 compared to 37 Celsius) and need to fly above ground level where the percentage of oxygen is reduced.
To cope with the high oxygen demands of flight the heart rate needs also to be enhanced, so birds typically have larger hearts than mammals of similar sizes, and they also have much higher heart rates with resting heart rates generally sitting between 150-350 beats per minutes for a medium-sized bird. (Humans 60 – 70bpm). The capacity for lung O2 diffusion is also greater in birds because of the exceptional thinness and large surface area of the gas exchange tissue. Nevertheless, the diffusion barrier appears to be mechanically stronger in birds than in mammals, so pulmonary blood flow and pressure can increase without causing stress failure.
So, with a one-way airflow, high volume of blood arriving at the thin gas exchange surfaces and high heart rate (8 times higher during flight) the natural flow of oxygen from the incoming air by diffusion is high. Coupled with this, avian blood has a greater capacity to take up and deliver oxygen to the body tissues.
Interestingly, birds with long necks have to take deeper breathers than those with shorter necks, as there will be more ‘dead space’ of air that does not reach the lung’s gas exchange surfaces.
Yet there is even more efficiency in the system. Avian muscle fibres are smaller than those of mammals, ensuring the easier movement of gases into and out of those highly metabolic tissues. And their nervous system is less vulnerable to high carbon dioxide levels. All of this allows the system to cope with the demands of their lifestyle.
Surface area to volume
Organisms gain or lose heat from their outer surfaces. They can, if it is kept moist, use their outer surface for the exchange of gases.
Imagine cubical animals:
1 x 1 x 1 Small organism
2 x 2 x 2
10 x 10 x 10 Larger organism
Surface area to volume ratio
6 : 1
3 : 1
0.6 : 1
Easy exchange of gases over their comparatively large surface, BUT easy heat gain or loss.
Gas exchange through the surface will be difficult BUT heat loss or gain is less significant. Needs a gas exchange organ – lung.
Effect of size on an organism’s metabolism
As organisms increase in size they need specialised organs (internal and moist) to take up and release waste gases, but heat control is easier.
Smaller organisms have a comparatively large surface area to volume, so gas exchange is easier. Yet, small warm-blooded organisms are in danger of losing too much heat as there is little body volume to generate heat through their metabolism.
Consider a minute aquatic organism such as Amoeba. From the data above one can suspect that diffusion through its surface could supply sufficient exchange of gases (O2 and CO2). It is unconcerned, mostly, by gain and loss of heat. However, a small bird living in a cool or cold environment, not exchanging gases through its outer layer, is in trouble because of potential heat loss with its comparatively large surface area when compared to a much bigger bird. Hence why small hummingbirds must hibernate at night. (But not larger birds). With such losses of heat, the energy intake of a small bird needs to be much greater (for each unit of weight) than a larger animal. Little birds seldom ‘enjoy’ cold climates and may force some to migrate.
Feathers are vital not only to aid flight but also for thermoregulation. They may need to trap insulatory air to reduce heat loss or gain. So, not all feathers are flight feathers, some are ‘down’ feathers, and their percentage and orientation will vary with environmental conditions. Maintaining feathers in optimal condition is a vital activity.
The figures usually quoted for the energy content of fats (lipids) and carbohydrates is 38KJ to 17KJ a gramme. A gramme of fat contains about twice the energy than carbohydrate. If birds need to have high energy stores, e.g. for migration, it is better to use fats. Migratory geese have higher fat stores than chickens (non-migratory) and will need to use it in energy release during migration.
Fats may be great energy stores, yet they metabolically need more oxygen than carbohydrates, and with high-flying migratory birds, this introduces a new problem. At high altitudes air pressure is lower, so lift is less. Hence greater flapping is needed at a time when oxygen levels are lower than at ground level. Under such conditions, birds risk going anaerobic with carbon dioxide levels causing body stress or death. Flying high may reduce air resistance and allows the chance to use back winds to aid you, but other negative factors come into play.
Birds, such as the high-flying, migrating Bar-headed Geese, take much deeper breaths and have larger lungs to cope with the low oxygen levels. Additionally, like high-living mammals, they possess blood haemoglobin that takes up oxygen more readily than a non-migratory species. Also, the goose heart’s left ventricle is more enriched with blood vessels to reduce the chance of it being oxygen-deficient. There are cellular modifications too to make oxygen usage more efficient.
Of course, we all know that the muscles of birds use one of two systems. Explosive muscles work mainly anaerobically (white meat), while slowly working muscles use oxygen (red meat). Red meat contains the fixed oxygen-holding pigment myoglobin which is absent in white meat.
The explosive-functioning muscles are to fly from predators, yet they soon become oxygen-deficient and exhausted. This is ideal for wild chickens and turkeys that are ground-dwelling and burst upwards but coast down to a safer location. Their leg muscles are functioning much of the time so will be red meat. However, those explosive muscles are not the correct design for migratory birds and they need slower but longer-lasting red muscle.
Birds are wonderful examples of how evolution adapts a basic animal design to many different niches – environmental options.
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The placing of organisms into groups some people think is a rather boring topic. I agree; yet understanding some aspects of classification makes life and studying organisms easier and rewarding.
Organisms in any group have features in common and possibly a common ancestor. I’m in a group: I follow Southampton Football Club and that is the common feature of Saints Supporters (as we are called). My ancestory was being brought up near the city of Southampton.
The PLANT KINGDOM has sub-sections (Divisions): liverworts, club mosses, hornworts, ferns, ginkgos, cycads, conifers and flowering plants (monocotyledonous and dicotyledonous groups).
(Sadly, not all botanists agree how to subdivide the plant kingdom … which makes it near impossible for everyone else.) (NOTE, if you are studying botany at degree level, stick to whatever system your professors says! She / he will be marking your examination scripts!)
Here, we will look only at the flowering plants and their FAMILIES.
When ‘in the field’ I often need to identify a plant. With most ID books using the plant family (rather than flower colour or plant size or habitat) to organise their system, knowing the family saves much effort.
Many people become confused with plant families. And, it is understandable as seldom is it explained.
The flowering plants – the Angiosperms.
These are plants that flower and have seeds produced in fruits. The seed being an immature plant consisting of a minute root, shoot, stem and one or two seed leaves – cotyledons. A fruit is produced from the ovary of the plant*. (Gymnosperms have seeds, but they are not contained within an ovary – gymnosperm = naked seeds …. as they are found on the surface of an open cone, so naked.)
[*What is the true definition of a fruit? A fruit is a mature, ripened ovary, along with the contents of the ovary.]
In my opinion, there are two sub-groups of the Angiosperms – the monocotyledonous plants (monocots) with one cotyledon in the seed, and the dicotyledonous plants (dicots for short) with two.
Monocots usually have leaf veins that run parallel and flower petals / sepals in multiples of threes.
Dicots have netted leaves and flower sepals / petals in combinations of four or five.
Plant families are decided on their flower structure. Size is of no consequence. Flower colour is of no consequence. Members of a plant family may be trees, shrubs or herbaceous, it makes no difference – it is flower structure that is crucial.
So, which floral features are important?
The number of floral parts i.e. how many petals or sepals?
Are the sepals coloured and look like the petals?
Do the petals all join to form a corolla?
Is the ovary above the junction of petals meet with the flower stem (superior ovary) or below it (inferior ovary)?
How many flowers are there on a flower stem and how are they organised?
Firstly, recall that flowers are in layers. The bottom layer comprises the sepals; next petals, then stamens and carpels at the top. They all join to the receptacle that sits atop the flower stalk. The receptacle can surround the carpels.
For example, the Orchid Family.
They all have parallel leaf veins, so are monocots and seeds have a single cotyledon. There are no dicot orchids.
Floral parts (sepals and petals) are in threes, but in a specific arrangement. The three sepals are at the top and sides. Two petals form a hood, while a large petal flows down at the front. That package is only found in the orchids.
Even parasitic orchids, with no green parts and brown flowers, have that structure.
UK wild orchids and exotic orchids from Costa Rica have the same structure.
Now perhaps go to your plant ID book, your flora, and skip through the pages to see the different plant families and seek out their characteristics (Often stated in the introduction to that family).
I do not know all the families … in fact, not even near! But, the more often I ID a plant the more families I start to understand.
Remember: eBay offers secondhand botany books at almost zero cost. They do not go out of date easily. That’s where my uni-level books come from.
I grew up not far from The Forest, as we called it. It was only later, when I had travelled the World, did I understand just how special it is. Lowland heath, its ecological label, is rare … really rare, so its plants and animals are treasures. It was first a royal hunting estate, after 1066, and its resident villagers were dispersed. Yet, with poor, sandy and gravel soils it must have been hard work to eke out a living there. Today, the surrounding population, within an hour’s drive, is large – Bournemouth and Poole, Eastleigh and Romsey, Southampton, Fareham, Gosport and Portsmouth. Their residents flock to this open space and many have loose dogs that are the curse of wildlife and wild areas. Even the dog poo is changing the ecology with extra nitrogen and an acidification of the pH.
Belatedly, the authorities are finally closing car parks and restricting ad-hoc parking along roads and lanes. ‘Full’ signs are needed on some days.
Annette and I took our caravan to near Brockenhurst, having booked our spot nine months ago. Once there we walk and gently explore, yet this time it was for me to lead a field trip.
I lead a U3A group called Flora and Fauna, and we aim to generate data for conservation organisations. This time, however, it was just a learning exercise.
The first location was the Reptile Centre, which was opened specially for us, and the lead forester taught the group about the UK’s reptiles (see the previous article). The ultra-rate Smooth Snake was the star, and we saw the adders, slow worms and green lizards. Later in the day, a mature male adder wandered across our routeway to re-enforce its design and beauty.
The Oak Inn at Bank delighted our hunger at lunch, before we headed into the mature forestry areas for woodland ecology.
Finally, a line transect was completed from wet heath to dry heath, looking only at three heathers: cross-leaved heath, ling and bell heather. The % cover, just to the nearest 10%, was recorded along a 90m line. The data clearly showed the plants’ niches. Cross-leaved heath is a damp-lover, bell heather only lives in the dryest locations and ling is the one that is tolerant of both conditions.
Our next excursion is to record orchids and butterflies for a conservation group and the UK Army on Salisbury Plain.
Beneath our feet is an ecosystem so astonishing that it tests the limits of our imagination. It’s as diverse as a rainforest or a coral reef. We depend on it for 99% of our food, yet we scarcely know it. Soil.
Under one square metre of undisturbed ground in the Earth’s mid-latitudes (which include the UK) there might live several hundred thousand small animals. Roughly 90% of the species to which they belong have yet to be named. One gram of this soil – less than a teaspoonful – contains around a kilometre of fungal filaments.
When I first examined a lump of soil with a powerful lens, I could scarcely believe what I was seeing. As soon as I found the focal length, it burst into life. I immediately saw springtails – tiny animals similar to insects – in dozens of shapes and sizes. Round, crabby mites were everywhere: in some soils there are half a million in every square metre.
Then I began to see creatures I had never encountered before. What I took to be a tiny white centipede turned out, when I looked it up, to be a different life form altogether, called a symphylid. I spotted something that might have stepped out of a Japanese anime: long and low, with two fine antennae at the front and two at the back, poised and sprung like a virile dragon or a flying horse. It was a bristletail, or dipluran.
As I worked my way through the lump, again and again I found animals whose existence, despite my degree in zoology and a lifetime immersed in natural history, had been unknown to me. After two hours examining a kilogram of soil, I realised I had seen more of the major branches of the animal kingdom than I would on a week’s safari in the Serengeti.
But even more arresting than soil’s diversity and abundance is the question of what it actually is. Most people see it as a dull mass of ground-up rock and dead plants. But it turns out to be a biological structure, built by living creatures to secure their survival, like a wasps’ nest or a beaver dam. Microbes make cements out of carbon, with which they stick mineral particles together, creating pores and passages through which water, oxygen and nutrients pass. The tiny clumps they build become the blocks the animals in the soil use to construct bigger labyrinths.
Soil is fractally scaled, which means its structure is consistent, regardless of magnification. Bacteria, fungi, plants and soil animals, working unconsciously together, build an immeasurably intricate, endlessly ramifying architecture that, like Dust in a Philip Pullman novel, organises itself spontaneously into coherent worlds. This biological structure helps to explain soil’s resistance to droughts and floods: if it were just a heap of matter, it would be swept away.
It also reveals why soil can break down so quickly when it’s farmed. Under certain conditions, when farmers apply nitrogen fertiliser, the microbes respond by burning through the carbon: in other words, the cement that holds their catacombs together. The pores cave in. The passages collapse. The soil becomes sodden, airless and compacted.
But none of the above captures the true wonder of soil. Let’s start with something that flips our understanding of how we survive. Plants release into the soil between 11% and 40% of all the sugars they make through photosynthesis. They don’t leak them accidentally. They deliberately pump them into the ground. Stranger still, before releasing them, they turn some of these sugars into compounds of tremendous complexity.
Making such chemicals requires energy and resources, so this looks like pouring money down the drain. Why do they do it? The answer unlocks the gate to a secret garden.
Soil is full of bacteria. Its earthy scent is the smell of the compounds they produce. In most corners, most of the time, they wait, in suspended animation, for the messages that will wake them. These messages are the chemicals the plant releases. They are so complex because the plant seeks not to alert bacteria in general, but the particular bacteria that promote its growth. Plants use a sophisticated chemical language that only the microbes to whom they wish to speak can understand.
When a plant root pushes into a lump of soil and starts releasing its messages, it triggers an explosion of activity. The bacteria responding to its call consume the sugars the plant feeds them and proliferate to form some of the densest microbial communities on Earth. There can be a billion bacteria in a single gram of the rhizosphere; they unlock the nutrients on which the plant depends and produce growth hormones and other chemicals that help it grow. The plant’s vocabulary changes from place to place and time to time, depending on what it needs. If it’s starved of certain nutrients, or the soil is too dry or salty, it calls out to the bacteria species that can help.
Take a step back and you will see something that transforms our understanding of life on Earth. The rhizosphere lies outside the plant, but it functions as if it were part of the whole. It could be seen as the plant’s external gut. The similarities between the rhizosphere and the human gut, where bacteria also live in astonishing numbers, are uncanny. In both systems, microbes break down organic material into the simpler compounds the plant or person can absorb. Though there are more than 1,000 phyla (major groups) of bacteria, the same four dominate both the rhizosphere and the guts of mammals.
Just as human breast milk contains sugars called oligosaccharides, whose purpose is to feed not the baby but the bacteria in the baby’s gut, young plants release large quantities of sucrose into the soil, to feed and develop their new microbiomes. Just as the bacteria that live in our guts outcompete and attack invading pathogens, the friendly microbes in the rhizosphere create a defensive ring around the root. Just as bacteria in the colon educate our immune cells and send chemical messages that trigger our body’s defensive systems, the plant’s immune system is trained and primed by bacteria in the rhizosphere.
Soil might not be as beautiful to the eye as a rainforest or a coral reef, but once you begin to understand it, it is as beautiful to the mind. Upon this understanding our survival might hang.
Unless something changes, all this is likely to get worse – much worse. In principle, there is plenty of food, even for a rising population. But roughly half the calories farmers grow are now fed to livestock, and the demand for animal products is rising fast. Without a radical change in the way we eat, by 2050 the world will need to grow around 50% more grain. How could we do it without wiping out much of the rest of life on Earth?
It’s not just the quantity of production that’s at risk, but also its quality. A combination of higher temperatures and higher concentrations of CO2 reduces the level of minerals, protein and B vitamins that crops contain. Already, zinc deficiency alone afflicts more than a billion people. Though we seldom discuss it, one paper describes the falling concentrations of nutrients as “existential threats”.
We might barely detect the loss of a soil’s resilience until, when drought strikes, fertile lands turn to dustbowls
Some crop scientists believe we can counter these trends by raising yields in places that remain productive. But their hopes rely on unrealistic assumptions. The most important of these is sufficient water. The anticipated growth in crop yields would require 146% more fresh water than is used today. Just one problem: that water doesn’t exist.
Over the past 100 years, our use of water has increased six-fold. Irrigating crops consumes 70% of the water we withdraw from rivers, lakes and aquifers. Already, 4 billion people suffer from water scarcity for at least one month a year and 33 major cities, including São Paulo, Cape Town, Los Angeles and Chennai, are threatened by extreme water stress. As groundwater is depleted, farmers have begun to rely more heavily on meltwater from glaciers and snowpacks. But these, too, are shrinking.
A likely flashpoint is the valley of the Indus, whose water is used by three nuclear powers (India, Pakistan and China) and several unstable regions. Already, 95% of the river’s flow is extracted. As the economy and the population grow, by 2025 demand for water in the catchment is expected to be 44% greater than supply. But one of the reasons why farming there has been able to intensify and cities to grow is that, as a result of global heating, glaciers in the Hindu Kush and the Himalayas have been melting faster than they’ve been accumulating, so more water has been flowing down the rivers. This can’t last. By the end of the century, between one- and two-thirds of the ice mass is likely to have disappeared. It is hard to see this ending well.
And all this is before we come to the soil, the thin cushion between rock and air on which human life depends, which we treat like dirt. While there are international treaties on telecommunication, civil aviation, investment guarantees, intellectual property, psychotropic substances and doping in sport, there is no global treaty on soil. The notion that this complex and scarcely understood system can withstand all we throw at it and continue to support us could be the most dangerous of all our beliefs.
Soil degradation is bad enough in rich nations, where the ground is often left bare and exposed to winter rain, compacted and wrecked by overfertilisation and pesticides that rip through its foodwebs. But it tends to be even worse in poorer nations, partly because extreme rainfall, cyclones and hurricanes can tear bare earth from the land, and partly because hungry people are often driven to cultivate steep slopes. In some countries, mostly in Central America, tropical Africa and south-east Asia, more than 70% of the arable land is now suffering severe erosion, gravely threatening future production.
Climate breakdown, which will cause more intense droughts and storms, exacerbates the threat. The loss of a soil’s resilience can happen incrementally and subtly. We might scarcely detect it until a shock pushes the complex underground system past its tipping point. When severe drought strikes, the erosion rate of degraded soil can rise 6,000-fold. In other words, the soil collapses. Fertile lands turn to dustbowls.
Some people have responded to these threats by calling for the relocalisation and de-intensification of farming. I understand their concerns. But their vision is mathematically impossible.
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A study in the journal Nature Food found the average minimum distance at which the world’s people can be fed is 2,200km. In other words, this is the shortest possible average journey that our food must travel if we are not to starve. For those who depend on wheat and similar cereals, it’s 3,800km. A quarter of the global population that consumes these crops needs food grown at least 5,200km away.
Why? Because most of the world’s people live in big cities or populous valleys, whose hinterland is too small (and often too dry, hot or cold) to feed them. Much of the world’s food has to be grown in vast, lightly habited lands – the Canadian prairies, the US plains, wide tracts in Russia and Ukraine, the Brazilian interior – and shipped to tight, densely populated places.
As for reducing the intensity of farming, what this means is using more land to produce the same amount of food. Land use is arguably the most important of all environmental issues. The more land farming occupies, the less is available for forests and wetlands, savannahs and wild grasslands, and the greater is the loss of wildlife and the rate of extinction. All farming, however kind and careful, involves a radical simplification of natural ecosystems.
Environmental campaigners rail against urban sprawl: the profligate use of land for housing and infrastructure. But agricultural sprawl – using large amounts of land to produce small amounts of food – has transformed much greater areas. While 1% of the world’s land is used for buildings and infrastructure, crops occupy 12% and grazing, the most extensive kind of farming, uses 28%. Only 15% of land, by contrast, is protected for nature. Yet the meat and milk from animals that rely solely on grazing provide just 1% of the world’s protein.
One paper looked at what would happen if everyone in the US followed the advice of celebrity chefs and switched from grain-fed to pasture-fed beef. It found that, because they grow more slowly on grass, the number of cattle would have to rise by 30%, while the land area used to feed them would rise by 270%. Even if the US felled all its forests, drained its wetlands, watered its deserts and annulled its national parks, it would still need to import most of its beef.
Only when livestock are extremely sparse is animal farming compatible with rich, functional ecosystems. For example, the Knepp Wildland project in West Sussex, where small herds of cattle and pigs roam freely across a large estate, is often cited as a way to reconcile meat and wildlife. But while it’s an excellent example of rewilding, it’s a terrible example of food production.
If this system were to be rolled out across 10% of the UK’s farmland and if, as its champions propose, we obtained our meat this way, it would furnish each person here with 420 grams of meat a year, enough for around three meals. We could eat a prime steak roughly once every three years. If all the farmland in the UK were to be managed this way, it would provide us with 75kcal a day (one 30th of our requirement) in meat, and nothing else.
Of course, this is not how it would be distributed. The very rich would eat meat every week, other people not at all. Those who say we should buy only meat like this, who often use the slogan “less and better”, present an exclusive product as if it were available to everyone.
Campaigners, chefs and food writers rail against intensive farming and the harm it does to us and the world. But the problem is not the adjective: it’s the noun. The destruction of Earth systems is caused not by intensive farming or extensive farming, but a disastrous combination of the two.
So what can we do? Part of the answer is to take as much food production out of farming as we can. As luck would have it, the enabling technology has arrived just as we need it. Precision fermentation, producing protein and fat in breweries from soil bacteria, fed on water, hydrogen, CO2 and minerals, has the potential to replace all livestock farming, all soya farming and plenty of vegetable oil production, while massively reducing land use and other environmental impacts.
But this remarkable good fortune is threatened by intellectual property rights: it could easily be captured by the same corporations that now monopolise the global grain and meat trade. We should fiercely resist this: patents should be weak and anti-trust laws strong. Ideally, this farm-free food should be open source.
Then we could relocalise production: the new fermentation technologies could be used by local businesses to serve local markets. As some of the world’s poorest nations are rich in sunlight, they could make good use of a technology that relies on green hydrogen. Microbial production horrifies some of those who demand food sovereignty and food justice. But it could deliver both more effectively than farming does.
Such technologies grant us, for the first time since the Neolithic period, the opportunity to transform not only our food system but our entire relationship with the living world. Vast tracts of land can be released from both intensive and extensive farming. The age of extinction could be replaced by an age of regenesis.
A British farmer’s revolutionary model of horticulture looks like magic, but is the result of years of meticulous experiments
Of course, we would still need to produce cereals, roots, fruit and vegetables. So how do we do it safely and productively? The answer might lie in our new understanding of the soil.
On a farm in south Oxfordshire, techniques developed by a vegetable grower called Iain Tolhurst – Tolly – seem to have anticipated recent discoveries by soil scientists.
Tolly is a big, tough-looking man in his late 60s, with etched and weathered skin, a broad, heavy jaw, long blond hair, one gold earring, hands grained with earth and oil. He started farming without training or instruction, without land or any means to buy it. After a string of misadventures, he managed to lease seven hectares (17.3 acres) of very poor land at a reduced rent, 34 years ago.
“No conventional grower would even look at this ground,” he told me. “It’s 40% stone. They’d call it building rubble. It isn’t even classed as arable: an agronomist would say it’s only good for grass or trees. But over the past 12 months, we harvested 120 tonnes of vegetables and fruit.”
Astonishingly, for these 34 years Tolly has been farming this rubble without pesticides, herbicides, mineral treatments, animal manure or any other kind of fertiliser. He has pioneered a way of growing that he calls “stockfree organic”. This means he uses no livestock or livestock products at any point in the farming cycle, yet he also uses no artificial inputs.
Until he proved the model, this was thought to be a formula for sucking the fertility out of the land. Vegetables in particular are considered hungry crops, which require plenty of extra nutrients to grow. Yet Tolly, while adding none, has raised his yields until they’ve hit the lower bound of what intensive growers achieve with artificial fertilisers on good land: a feat widely considered impossible. Remarkably, the fertility of his soil has climbed steadily.
On my first visit, one June, I was struck by the great range and health of Tolly’s crops. One plot was a blue haze of onion plants, another a patchwork of sea greens: young cauliflower plants, several kinds of cabbage and kale. There were rows of rainbow chard with gold, green, white and crimson stems. Broad bean pods had begun to sprout from tight pillars of flower. His potatoes were in full bloom, nightshade sinister, stamens like yellow stings. Courgettes extruded rudely behind their trumpet flowers. There were carrots, tomatoes, peppers, beans of all kinds, herbs, parsnips, celeriac, cucumbers, lettuces. He raises 100 varieties of vegetables, which he sells in his farm shop and to subscribers to his veg box.
Separating the plots were untended banks, in which scientists studying his farm have found 75 species of wildflowers. These banks are an essential component of his system, harbouring the insect predators that control crop pests. Though he uses no pesticides, none of the vegetable plants I saw showed signs of significant insect damage: the leaves were dark and wide, with scarcely a hole or a spot.
Almost single-handedly, through trial and error, Tolly has developed a new and revolutionary model of horticulture. At first it looks like magic. In reality, it’s the result of many years of meticulous experiments.
Two of his innovations appear to be crucial. The first, as he puts it, is to “make the system watertight”: preventing rain from washing through the soil, taking the nutrients with it. What this means is ensuring the land is almost never left bare. Beneath his vegetables grows an understorey of “green manure”, plants that cover the soil. Under the leaves of his pumpkins, I could see thousands of tiny seedlings: the “weeds” he had deliberately sown. When the crops are harvested, the green manure fills the gap and soon becomes a thicket of colour: blue chicory flowers, crimson clover, yellow melilot and trefoil, mauve Phacelia, pink sainfoin.
“There’s green manure under the green manure,” Tolly told me. “As soon as we cut the bigger plants, it comes into flower, and the bees go crazy.”
Some of the plants in his mix put down deep roots that draw nutrients from the subsoil. Every so often, Tolly runs a mower over them, chopping them into a coarse straw. Earthworms pull this down and incorporate it into the ground. “The idea is to let the plants put back at least as much carbon and minerals as we take out.”
Tolly tells me that “the green manure ties up nutrients, fixes nitrogen, adds carbon and enhances the diversity of the soil. The more plant species you sow, the more bacteria and fungi you encourage. Every plant has its own associations. Roots are the glue that holds and builds the soil biology.”
The other crucial innovation is to scatter over the green manure an average of one millimetre a year of chipped and composted wood, produced from his own trees or delivered by a local tree surgeon. This tiny amendment appears to make a massive difference. In the five years after he started adding woodchip, his yields roughly doubled. As Tolly explains: “It isn’t fertiliser; it’s an inoculant that stimulates microbes. The carbon in the wood encourages the bacteria and fungi that bring the soil back to life.” Tolly believes he’s adding enough carbon to help the microbes build the soil, but not so much that they lock up nitrogen, which is what happens if you give them more than they need.
What Tolly appears to be doing is strengthening and diversifying the relationships in the rhizosphere – the plant’s external gut. By keeping roots in the soil, raising the number of plant species and adding just the right amount of carbon, he seems to have encouraged bacteria to build their catacombs in his stony ground, improving the soil’s structure and helping his plants to grow.
Tolly’s success forces us to consider what fertility means. It’s not just about the amount of nutrients the soil contains. It’s also a function of whether they’re available to plants at the right moments, and safely immobilised when plants don’t need them. In a healthy soil, crops can regulate their relationships with bacteria in the rhizosphere, ensuring that nutrients are unlocked only when they’re required. In other words, fertility is a property of a functioning ecosystem. Farm science has devoted plenty of attention to soil chemistry. But the more we understand, the more important the biology appears to be.
Can Tolly’s system be replicated? So far the results are inconclusive. But if we can discover how to mediate and enhance the relationship between crop plants and bacteria and fungi in a wide range of soils and climates, it should be possible to raise yields while reducing inputs. Our growing understanding of soil ecology could catalyse a greener revolution.
I believe we could combine this approach with another suite of innovations, by a non-profit organisation in Salina, Kansas, called the Land Institute. It’s seeking to develop perennial grain crops to replace the annual plants from which we obtain the great majority of our food. Annuals are plants that die after a single growing season. Perennials survive from one year to the next.
Large areas dominated by annuals are rare in nature. They tend to colonise ground in the wake of catastrophe: a fire, flood, landslide or volcanic eruption that exposes bare rock or soil. In cultivating annuals, we must keep the land in a catastrophic state. If we grew perennial grain crops, we would be less reliant on smashing living systems apart to produce our food.
For 40 years, the Land Institute has been scouring the world for perennial species that could replace the annuals we grow. Already, working with Fengyi Hu and his team at Yunnan University in China, it has developed a perennial rice with yields that match, and in some cases exceed, those of modern annual breeds. Farmers are queueing up for seed. While annual rice farming can cause devastating erosion, the long roots of the perennial varieties bind and protect the soil. Some perennial rice crops have now been harvested six times without replanting.
Perennials are their own green manures. The longer they grow, the stronger their relationships with microbes that fix nitrogen from the air and release other minerals. One estimate suggests that perennial systems hold five times as much of the water that falls on the ground as annual crops do.
The Land Institute is developing promising lines of perennial wheat, oil crops and other grains. The deep roots and tough structures of perennial plants could help them to withstand climate chaos. The perennial sunflowers the institute is breeding have sailed through two severe droughts, one of which entirely destroyed the annual sunflowers grown alongside them.
While no solution is a panacea, I believe that some of the components of a new global food system – one that is more resilient, more distributed, more diverse and more sustainable – are falling into place. If it happens, it will be built on our new knowledge of the most neglected of major ecosystems: the soil. It could resolve the greatest of all dilemmas: how to feed ourselves without destroying the living systems on which we depend. The future is underground.
George Monbiot will discuss Regenesis at a Guardian Live event in London on Monday 30 May. Book tickets to join the event in person, or via the livestreamhere.
Regenesis: Feeding the World Without Devouring the Planet by George Monbiot is published by Penguin Books at £20 on 26 May. To support the Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.
I’ve always been a fan of the underdog. If some creature is being ‘got at’ then I’m prepared to put in some effort to attempt to right-the-wrong. That was how it was when I started working with the Mammal Society and then the Otter Trust to stop the hunting of the animal with dogs, the use of traps by waterkeepers and to reverse the trend to extinction that was happening in the 1970s. Human aggression, water pollution and a total disregard of the environment was where I started. And it worked! I set up a nationwide Otter Conference in 1976 and that helped push the survival of the otter in the correct direction.
Now, snakes need some support. Their numbers are declining, and their habitat often so divided that genetic flow is impossible, and inbreeding depression a possibility. I did watch adders a few years back and have carried out some very basic research, and the creatures are unaggressive when left alone. Only considerable human or dog aggression causes them to respond negatively. So, if you go out looking for and at snakes you can proceed without fear of being bitten.
The UK has three snake species: the Adder (Viper), Grass Snake and Smooth Snake. All are said to be declining and the smooth snake is already rare. The frequent heathland fires are a negative influence too.
The snakes have their own niches, which largely fail to overlap. The smooth snake are heathland specialists, grass snakes are wetland creatures and the adder a grassland and wood pasture animal over much of its range. Yes, that is an simplification and I have seen adders on heathland at Pullborough Brooks and a grass snake in my, edge of woodland, grassy garden … but it is a fair reflection.
Why the decline? Well, many reasons.
Firstly, people seem to dislike them. A colleague at work played golf and happily said he killed any snakes he saw with a golf club. No reason really. He was not threatened or, worse, attacked. Just fancied killing them.
Two, their habitat has been lost to farming, golf courses or housing / industry.
Three, dogs, whose numbers seem to increase exponentially, disturb the animals and inhibit hunting and mating.
Four, men with guns. A friend was filming adders for the BBC and all the animals he captured had shotgun pellets embedded in them. The lead shot would, of course, kill them immediately or poison them over a short time.
Five, pheasants (Asian birds) and chickens eat young reptiles and soon eliminate them. The Netherlands bans pheasants to preserve their reptiles. If the UK stopped pheasant rearing the snakes would fair much better. An RSPB reserve in west Wales had a healthy snake population until a pheasant shoot started – the snakes are now all gone.
The Adder or Viper.
Vipera berus, the adder is one of our three native snake species. It is most often seen on heaths and grassy coastal areas. Undisturbed grassy areas are great locations. However, its secretive nature and camouflaged markings mean it often goes unnoticed. Whilst it has a large range across the UK, recent declines, especially in central England, mean it is of major conservation concern. The adder is the UK’s only venomous snake. Though potentially serious, adder bites to humans or dogs are very rarely fatal. There are only around ten recorded cases of death from adder bite in the last 100 years, and most bites occur when the snake has been disturbed or deliberately antagonised.’ ARC.
The animal is found across England, Wales and Scotland but you will need to work hard to find them in many locations. In my own area, north-west Hampshire they have been hugely impacted by pheasant breeding. Even gamekeepers tell me that their snakes have vanished. I would struggle to find one within 20 miles, although I know of many locations where they have been previously. However, Martin Down NNR is a good location.
The distinct black and white colour of the typical male can be much darker – the black adder. The females are usually slightly larger and have an olive / brown / copper complexion.
Adders are not easy to see in the wild as they merge well with their background, are often coiled to conserve warmth and seldom are seen moving. The animals coil and uncoil, round their body or flatten it depending on the weather conditions. I have read reports of their climbing bushes to gain the early or late sunlight, yet I have never witnessed that.
I have seen adders as early as February 14th in the New Forest, and some reports indicate they can be active all winter in mild locations.
I associate male adders in combat / dancing at the same time as the early purple orchids are in flower – April or May. Why? Well, I was lying down photographing said orchid when an adder pair started their combat dance alongside me! I have lived to tell the tale.
The dance is a combat of strength with the animals loosely intertwined and moving. They are then oblivious of all around them. The winner will hold that key territory and will mate with the local female.
Female adders breed annually in warm locations and less frequently in colder areas. Their eggs are incubated internally, and you are seen from late summer. The babies are worm-like and vulnerable to avian predation.
Lifespan is said to be up to ten years.
My filming friend was lying down in his home adder pit when a female evaded his cycle clips – employed to stop access to his trousers. The female spent several hours basking on his bum but inside his trousers!
Prey animals are poisoned by injection and then followed until they are immobile and then swallowed whole. Mice, voles and lizards are suitable foods. Hunting may occur at night.
The venom of young adders is stronger than that of adults.
Where to look? Undisturbed grassland fringes and especially grassy areas near heathland. Purbeck is an excellent location.
When to look? When you can see a shadow there will be active snakes. However, they are best viewed early April or May and in the early morning.
How to look? Walk very slowly. They will not hear quiet conversation yet will feel footfall if it is heavy.
Snakes, including adders, are important parts of the ecosystem. Unless actively disturbed they avoid humans and dogs.
The Grass Snake, Natrix helvetica
The UK’s longest snake at nearly a metre.
Grass snakes are found throughout England and Wales and are most likely seen in wet locations. Around Andover the River Test is a good location and especially the Longstock Water Gardens (John Lewis). There are also reports of these animals from Stoke and along the A303. The Salisbury Water Meadows was a good site and I have spotted them swimming in the River Avon.
Feeding primarily on fish and amphibians, grass snakes can occasionally venture into garden ponds in the summer months, particularly in rural or semi-rural parts of the south. They are not to be feared.
Grass snakes are non-venomous and are extremely timid, moving off quickly when disturbed. If cornered they can feign death, and if handled frequently, produce a foul-smelling excretion. This excretion happened to me as I saved a large animal from my polecat’s attention. My hand and clothes stank for a week, but I soon released the grass snake unharmed.
Grass snakes are Britain’s only egg-laying snake. Females lay eggs in June or July, normally in rotting vegetation (including garden compost heaps) which acts as an incubator. The eggs hatch into miniature versions of the adults in the late summer months.
All snakes are protected by law. Observe them and leave them alone.
The Smooth Snake, Coronella austriaca
I have not seen one actively in the wild. It is a rare animal and a heathland specialist. They also are infrequent baskers, so attempting to spot one is an unrewarding task!
Smooth snakes usually emerge from hibernation in April-early May. They are non-venomous and feed mainly on common lizards, slow-worms and small mammals (especially shrews and nestling rodents), which are captured and constricted in the coils of its body. Live young, which look very similar to the adults, are born in September. Smooth snakes are long-lived and females tend not to breed every year. The smooth snake is a secretive animal and when it basks in the sun it does so entwined amongst the stems of heather plants, where it is superbly camouflaged.
As with all UK snakes, the best location to view them is at The Reptile Centre in the New Forest. There you should see all the types in their large outdoor enclosures.
We have Palmate Newts, Lissotriton helveticus, in and around our pond. These are amphibians and are rather like lizards in appearance, but with moist, unscally skins. They are often missed by gardeners as they keep a low profile, especially in weedy ponds.
They are not organisms I associate with rivers, although their distant cousins, frogs, will spawn in the shallow and current-free areas. But it could be I’m just not seeing them. You may know otherwise.
Newts are not active in the colder months, and I first see them when our frog tadpoles first appear – in mid-March. And the newts then hoover-up tadpoles at a rapid rate, and I currently can see zero tadpoles despite having around 30-spawn masses in February. Happy and well-fed newts, I think.
Our newts are Palmates, and that is not what one might suspect as they are said to prefer acidic, fish-free ponds.
“Telling smooth newts apart from palmate newts can be trying. Both are brown in colour, with a yellow/orange underbelly, and both species rarely exceed 10cm. The best way to tell females apart is the fact that the throat of the smooth newt is spotted and that of the palmate newt is plain pink or yellow. The male, in breeding condition, is easy to tell apart from the smooth newt. Palmate newt males have a filament at the tip of the tail and black webbing on the back feet, neither of which are present in smooth newts.” Amphibian and Reptile Conservation website.
Our newts have the black webbing, yet the water is distinctly alkaline as the pond is ‘topped up’ with calcium-rich tap water in spring and summer, although overwinter the rainwater will make the water mildly acidic. However, the original newts were transported here from elsewhere, which could have had naturally acidic water. Regardless, they have survived with us for over thirty years.
In the pond, they move around in groups, often a female with two accompanying males. Often the males advance and tail waft hormones (pheromones) to stimulate the female to mate. The females annually lay over 150 eggs, each individually wrapped in water plants. These eggs are 1.3–1.8 mm in diameter (2.2–3 mm with capsule). Surviving eggs hatch to form (my expression) minute newtlets with feathery external gills. There can be a surprisingly large number of newtlets if you investigate a weedy area with a fine net. The external gills are lost before the young emerge onto land and then they breathe through their moist skin and roof of the mouth.
Some publications suggest Palmate Newts are nocturnal – not here! They are very active even in bright sunlight. The species competes badly when fish are present.
You should spot the adult newts all summer, yet they move onto land in late summer and can occasionally be found in damp situations. Over winter they hibernate.
Smooth and Great Crested Newts are also found in the UK.
Website revamp is on its way! Easier searching for articles soon.
Spring in the mid-uplands of Crete is the main time for seeing the flowers on wild orchids. The mild winters, hot summers with winds often coming from the Sahara and the calcareous soils all add to making this a favourable environment. This last winter the rain and snow exceeded expectations, so has encouraged vegetative growth.
You will look in vain for woodland orchids in most places, as there is little woodland, so it is in the open maquis (called phrygana in Crete) that one explores. The three genera you would probably spot are Orchis, Ophrys and Serapias. All these are also found in the UK, but Serapias is an occasional migrant especially to the south-west.
Orchids are short-lived perennial plants that generally grow from a pair of tubers. Here, at Forest Edge, few survive more than a couple of years in a flowering state.
They are monocotyledonous, with parallel veins on their strap-like leaves, a cluster of flowers on the flower stalk, have colourful bracts and a package of six tepals (petal-like sepals and petals) and their pollen is produced in pollinia. Because their flowers are so different the group attracts more attention than perhaps they deserve, however they can be extraordinarily attractive, and their looking like wild insects to encourage copulation and hence pollen dispersal is an added human attraction. The Ophrys genera’s flowers appear insect-like and are still evolving, so crosses are common and that also generates interest. One is never quite sure what any plant’s flowers will look like – they change colours and patterns. I have a Military x Monkey orchid cross in my garden that is about to flower.
The problems in Crete for the orchids, and flora in general, are the sheep and goat herds plus the ploughing up of orchid-rich areas. Perhaps understandably, the struggling locals gain nothing from their wild orchids and care little. Ditto the authorities, although we have travelled to Crete twice because of them – and that is good income. I have heard it said that the plains above Spili have some conservation protection, yet it is not obvious.
Where and when to visit?
April and early May are the best time. Location – the ‘orchid superhighway’ is on the road between Spili and the Amari Valley. However, you will find orchids elsewhere when animal flocks are not present. Try the Minoan site near Armeni or near Moni Arkadiou. In the east Plakia and the wonderful Katharo (above Kritsa) have proven good sites.
Botanists from far and wide are attracted to the Spili area and human trampling is an issue. The area needs wardening. It will not happen! We encountered numerous goat and sheep flocks crisscrossing the area, trampled plants and orchid sites ploughed.
As I said above, ophrys orchids can be very variable and happily cross with other species, so putting an absolute name to any given plant is problematic. Our local guide said we had also seen Ophrys herae and kedra, but my photographs are not clear enough to decide. Barlinia robertiana and Ophrys apifera were at the Minoan site and not photographed this time.
For Annette and myself, being in wild places with the sights and sounds of wildlife is a pleasure in itself. Putting names to plants is okay, but not majorly important to us. The ecology is important, yet deciding why that orchid thrives there and not just over there is quite beyond me!
And, yes, my camera needs changing. Not the best images.