Innholdsfortegnelse for August 2020 i BBC Wildlife Magazine

1 | SPIDER CRAB Shell suits People on a beach seldom realise there’s a carnival of life within a stone skim of the shore. What biologists refer to as the lower intertidal zone is only exposed at the very lowest tides, perhaps once or twice a year, and attracts creatures you’d think stay in much deeper water. At various times, this bustling world is visited by mackerel, catsharks, rays, flatfish, octopuses, lobsters, sea squirts and much else besides. Some are here to feed, others to mate or lay eggs, but spider crabs come to moult. Common spider crabs dwarf the greenish-brown shore crabs familiar from rock pools, with a red body just about big enough to cover a dinner plate, and spindly legs that span up to half a metre.…

“This report says we are late to the party and we need to get on with it.” The Government has signalled its intention to pursue a radical new approach to the conservation of England’s sea and coastal areas, with the publication of a report into Highly Protected Marine Areas (HPMAs). For the first time, ministers will consider banning almost everything from extractive mineral industries to commercial and recreational fishing from large areas of Britain’s territorial waters to permit their ecological recovery. HPMAs are also being touted as critical carbon sinks to offset the impacts of climate change. “Global marine sediment carbon stocks can be equal in size or greater than terrestrial carbon stocks such as forests,” the report states. “With greater protection, the ecosystems’ ability to provide carbon sequestration will…

WHAT IS IT? If any plant could be described as more than the sum of its parts, this new species of helmet orchid is surely it. The parts in question comprise one fingernail-sized leaf and a single bloom. But what exquisite parts they are, and how well they suit each other – this is beauty pared down to its bare essentials. WHERE IS IT? Helmet orchids are pollinated by fungus gnats, which mistake the flower for a mushroom and transfer pollen as they rummage around for a suitable egg-laying site. This latest addition to the group grows on forest floors in the Philippines. FIND OUT MORE Phytotaxa bit.ly/2BUJIVW…

There’s a wild animal market called Oluwo on the outskirts of Lagos in Nigeria that’s been called a “nuclear bomb waiting to happen”. The quantity and diversity of species on sale and the unsanitary conditions are both factors that could release a mushrooming radiation of a novel, potentially lethal virus resulting in the next global pandemic, the remark suggests. If you’re not too squeamish, a number of videos online reveal its brutal reality. In the opening shot of one film, you see civets – incorrectly called “bushdogs” – and tiny forest antelopes known as duikers, and when the stallholder is interviewed she claims to also sell “pangolins, bush rats and all sorts of animal”. Later we see monstrous cane rats – known as grasscutters – resembling baby hippos, and genets,…

The still night air echoed with a faint murmur, a sound resembling a hint of thunder that rolled across the savannah, building to a crescendo as the lion drew closer. Scarface turned his head to the wind, his right eye staring blindly into the darkness, his magnificent mane of chocolate-brown hair encircling his muscular neck. His flanks heaved with each grunting roar, his barrel chest forcing air from deep within his body to produce an explosion of sound. He stopped, listening intently. Five kilometres away in the Musiara Marsh, he could hear the faint sounds of his pride-mates, as each added their voice to the wind. Sometimes the pride males turn and run, sometimes they stand and fight, and the ensuing battles are brutal. This encounter near the Marsh in…

The cuckoo female will spend the spring laying up to 26 eggs in various nests. It’s a sunny spring day in the Sobarriba, a plateau 950m above sea level in northern Spain, and a warm breeze is carrying a faint smell of wild thyme and lavender, which grow in the hedgerows and meadows of this low-intensity agricultural landscape. For nearly 10 minutes, we have been observing a great spotted cuckoo female perching on a branch of a tall poplar tree, just a couple of meters away from a carrion crow nest that we need to check for new eggs. The crow female is sitting on the nest, in an incubating posture, ignoring the cuckoo, though she must have seen it. We have never witnessed an active defence by breeding crows…

Healthy tropical reefs look like lush underwater gardens, covered in rainbow-hued hard and soft corals, with psychedelic fish flitting around. Corals get their colours from single-celled algae inside them, which contain photosynthetic pigments that harness the sun’s energy and thus provide food. What about the fishy multitudes? Some evolved colour as camouflage – for example, the pink pygmy seahorse hides in coral fans. Cleaner wrasse use their blue-and-yellow stripes to advertise their services to other fish. Meanwhile, fangtooth blennies deploy colour for deception – they mimic the cleaners, but rather than nibble parasites off visiting fish, take bites of skin instead. But when sea temperatures rise, this ecosystem’s vibrancy rapidly drains away. Heat-stressed corals eject their algae and lose colour, a phenomenon called coral bleaching.…

Northern cardinals are well known for their vibrant and alluring plumage, and are the official state bird in more US states (seven) than any other species. But how do these beauties, a common sight across the eastern USA, get their fabulous colours? Male cardinals are bright red, while females are paler brown, with red found only around their wings, tail and crest. Carotenoid pigments are responsible for the red coloration. These pigments are not produced automatically, but instead obtained through dietary sources, much as flamingos famously do. In the case of cardinals, they come from carotenoid-rich fruits, berries and seeds, and certain other plant parts. It has been suggested that the reddest males attract higher quality females and manage to pair up earlier in the season, while also obtaining higher-quality…

TV choice Weird and wonderful Delight in the differences of South America’s diverse wildlife. SOUTH AMERICA’S WEIRDEST ANIMALS NATIONAL GEOGRAPHIC WILD, FROM 2 AUGUST “Evolution is an eternal quest to find solutions to the ever-changing problem of survival and, every now and then, it coughs up quite the oddity,” says the narrator of this new three-part series. The programme gives us a quick-fire look at an eclectic mix of species: tapirs, who use their short, prehensile trunks as snorkels; scarab beetles who dine out on dung; and viscachas – rabbit-like rodents “tailor-made for living in the unforgiving Altiplano environment” – to name a few. Rather than taking an in-depth look at only a few species, a variety of interesting and unusual biology and ecology are given their five minutes of…

“There on the reef was a giant moray eel, scattering debris across the seabed.” I’d always considered moray eels faintly ridiculous. Sure, those gaping jaws and beady eyes are unnerving at first glance. But after a few underwater encounters, a moray guarding its patch of coral looks less like a threatening display, more like an awkward grin. I was on a night dive in the Red Sea, when my scuba buddy gestured with his torch beam to get my attention. There on the reef was a giant moray ripping into the coral, scattering debris across the seabed. It seemed to be looking for something but we couldn’t work out what. After a brief discussion employing a combination of recognised scuba hand signals and a few made up on the spot,…

Water crowfoot There are seven species of these beautiful white-flowered buttercups, which grow in still or running water. Some have both floating (laminar) leaves and submerged, thread-like (capillary) leaves. However, the classic chalk stream species, such as river water crowfoot and chalk stream water crowfoot, have just the submerged ones. Their large beds are a sign of a healthy watercourse. Watercress This salad section staple grows abundantly in the wild along many chalk streams. It’s distinctive for its sprawling, hollow stems, which bear the familiar glossy-green paired leaflets. Clusters of white flowers atop the stems are obvious during high summer. Grayling Fondly known as the ‘lady of the stream’, this silvery freshwater fish has a huge, multi-coloured, chequered dorsal fin – its most distinctive feature. The species prefers clean, fast-flowing…

While most animals are superficially symmetrical, there are almost always subtle differences between left and right: the arrangement of the internal organs; which hand one prefers to hold a pen with; the direction in which a shell coils. So when a rare left-handed snail popped up in a London garden, it gave scientists a unique opportunity to study the root of this mysterious phenomenon, with a lot of help from citizen scientists. “I’d never come across a left-coiling garden snail before,” says Angus Davison, a University of Nottingham biologist, who took custody of the London specimen. The majority of garden snails are right-handed, meaning their shells coil in a clockwise direction. Only about one in 40,000 snails are ‘lefties’. Part of the reason for their rarity is that the arrangement…

Some coconut water and oil has been removed from supermarket shelves after it emerged the products were made using fruit picked by captive pig-tailed macaques. A PETA (People for the Ethical Treatment of Animals) Asia investigation revealed that monkeys in Thailand are being kept chained, abusively trained and forced to climb trees to pick coconuts that are used to make coconut milk, meat, flour, oil and other products. The animal rights group describes the primates as being treated like “coconut-picking machines” and says male monkeys are able to pick up to 1,000 coconuts a day. It has found eight farms where macaques were forced to pick coconuts for export around the world. “These curious, highly intelligent animals are denied psychological stimulation, companionship, freedom and everything else that would make their…

GERRIT VYN is a wildlife photographer and cinematographer for the Cornell Lab of Ornithology. See more of his work at gerritvynphoto.com…

Since 1980, Kenya has lost on average 70 per cent of its wildlife, due to the impacts of a burgeoning human population. The wildebeest migration – the spectacular movement of 1.3 million animals that circle the Mara Reserve and Serengeti National Park (in neighbouring Tanzania) in search of fresh grazing and water, alongside hundreds of thousands of zebras and Thomson’s gazelles – bears witness to those changes. The Mara occupies the northernmost zone of the migration loop, and in the past, approximately half of the wildebeest would push across its border, spending up to four months in the reserve (and the adjacent wildlife conservancies) during the dry months from July to October. Today, due to competition with livestock for grazing, fencing and the development of land for farming and settlements,…

In Europe, there are only two species of brood parasitic birds: the common, cuckoo – which is found throughout the Palearctic and parasitises a great number of different host species – and the great spotted cuckoo, which is found in Southern Europe and Africa. The great spotted cuckoo in Europe is specialised on corvids – magpies and carrion crows. Occasionally, it can lay eggs in nests of jackdaws and choughs. Other hosts, in its African range, are hole-nesting starlings, pied crows and black crows.…

Hoverflies may be renowned for it, but many other insects do it too, including bees, wasps, beetles and other types of fly, all of which land vertically on flowers, helicopter-style. But the best hoverfly hoverers are those that guard a 3D territory in mid-air. It might be a shaft of sunlight across a woodland path, a sheltered open space against a hedgerow, or a small forest clearing. The resident hoverfly will hang in the air, stock still, a few metres off the ground. Every now and again, it suddenly buzzes out sideways to inspect an intruder or check out a potential mate. The front of a male hoverfly’s head is virtually all eyes – two huge hemispheres that touch each other. This gives the insect all-round vision to monitor its…

In days gone by, the word ‘fish’ was pinned to virtually any creature that lurked beneath the waterline. Gradually, as people paid more attention to the biology of those animals, it became clear that some ‘fish’ belonged to other groups, such as reptiles or mammals. This left a motley collection of aquatic vertebrates, including sharks, stingrays, hagfish, sturgeon, lungfish, goldfish and tuna. They are all animals that (usually) breathe through gills, have bodies covered in scales (though not always) and limbs in the form of fins. The problem is that birds, frogs, lizards, turtles, mammals and all the other vertebrates evolved from fish ancestors. So, strictly speaking, those land-dwelling vertebrates should all be called fish, too. Generally, though, most ichthyologists are content to refer to the closely related gathering of…

1 WHAT MAKES ACORNS GO KNOBBLY? Knopper galls, as they’re known, are caused by the larvae of a tiny wasp, first recorded in Britain in the 1960s. It belongs to a famous family of master architects, the gall wasps, which are parasites whose larvae develop inside plants. There are thought to be around 90 species in Britain and nearly all of them use oaks, giving rise to a weird and wonderful range of galls. From ‘artichokes’ to ‘apples’, they’re found throughout the year. 2 BUT HOW DO GALLS FORM? We used to think trees formed them as damage limitation, but now know the wasp larvae are effectively hijackers. They seem to secrete chemicals that somehow manipulate their host oak tree into producing abnormal growth. This includes snug chambers…

I read the absorbing piece by Helen Pilcher with great interest (Adapt or die, April 2020), until I came to the phrase ‘Scientists estimate that dozens of species go extinct every day’. Really? That would be a minimum of 9,000 a year, which I simply don’t believe. A trawl of the internet gives the rather precise figure of 137 species becoming extinct each day, so 50,000 a year. These exaggerated claims do wildlife conservation no favours, because the figures are never backed up with evidence. What I want to know is what has gone extinct in the last 70 years? I think I would remember the flagship species that have gone forever. But perhaps it’s my natural optimism that believes some individuals may still survive. Hilary Bradt, via email Helen…

Why are you championing the leopard seal? They have a reputation as one of Antarctica’s most formidable creatures, but there is still so much we don’t know about these solitary animals. Getting the opportunity to spend some time with multiple leopard seals in their natural environment – in February 2020, with G Adventures – was a lifelong dream come true. I saw them hunt, haul out on icebergs, interact with other leopard seals, ambush gentoo penguins… and puncture our Zodiac! What do we know about leopard seals? “They are excellent at stalking prey, hiding behind icebergs before they attack.” They play an important role in the ecosystem and are opportunistic feeders: their diet includes cephalopods, penguins, seals and krill. As well as sharp canines and incisors, the species has tricuspid…

Oh, a deer Introduced to the UK from the Mediterranean (on more than one occasion), fallow deer were historically kept in the deer parks of Britain’s gentry. Eventually, they escaped such confines and grew in number. You may spot them in broadleaf or coniferous woodland as well as on open agricultural land. Now numerous and widespread across England and Wales, they certainly seem to have made themselves at home here. Look closely This leaf-tailed gecko blends in beautifully with its background of tree bark. Found (though perhaps only by the eagle-eyed) in Madagascar, these arboreal reptiles rely on their coloration and jagged outline – created by flaps of skin – to avoid ending up as lunch for the local owls, rats and snakes. Like other gecko species, these lizards have…

Domestic cats and house mice go together like, well… Tom and Jerry. And now, biologists have found that these archetypal arch enemies have an intimate evolutionary history going back many thousands of years. It is pretty well established that the house mouse – one of the most successful invasive species on the planet – originated in southern Asia when humans started adopting sedentary agricultural cultures reliant on the storage of grains. The suspicion has long been that the domestication of the African wild cat was driven by humans’ need to protect their precious larders from the rapacious rodents. An international team of scientists has now used genetic and archaeological evidence to provide some firm evidence for that theory. They’ve shown that, as the mice have spread to human settlements around…

BY JULY, 770,000 people had signed a petition calling for a law requiring all new-build housing to include hedgehog-friendly fence holes, but demonstrating that they make a difference has been difficult. The theory behind the petition, launched in October 2018 by conservationist Hugh Warwick, is simple. As garden boundaries fragment available habitat for hedgehogs, which roam large areas, the CD-sized gaps represent a neat solution. “Anecdotally, I have plenty of stories about hedgehogs using these holes,” says Warwick. “We know it works, but we can’t yet prove it!” The problem, as Professor Fiona Mathews of the Mammal Society points out, is that there are no published studies. To rectify this, the People’s Trust for Endangered Species and British Hedgehog Preservation Society are helping fund new research at the University of…

There is something unsettling about the term ‘invasive non-native species’, as though there is something sinister going on, and these plants and animals have somehow sneaked into the country while we were looking the other way. But often, nothing could be further from the truth. Not only have we held the door open for them, we’ve thrown them a lavish welcome party. Plants in particular were often brought in as exotic curiosities by those lovers of the strange – the Victorians. Many still brighten our gardens quite happily, but some have taken to their new home rather too well. Don’t be fooled by these pretty flowers. In their own land, where they evolved, natural enemies keep their numbers in check. But in the UK, they have no such adversaries. Inside…

If you have ever marvelled at dragonflies zooming over a pond, with their sensational acceleration, handbrake turns, vertical ascents, loop-the-loops and screeching stops, you’re not the only one. Nature’s most ancient and finest aviators – they can even fly backwards – are the inspiration for engineers perfecting the latest generation of tiny drones, which like the insects boast four independently mobile, flapping wings. When it comes to drone technology, it seems that the sky’s the limit (battery life permitting). Unmanned aerial vehicles (UAVs), or drones as they are invariably known outside the industry, are having a moment. The Civil Aviation Authority (CAA) estimated that 1.5 million were bought as Christmas presents in Britain in 2017, since then sales figures have only gone one way. Then there are the squadrons of…

WILDLIFE SURVEYS Drones have proved ideal for monitoring inaccessible seabird and sealion colonies, and for locating herds of herbivores in remote wilderness areas (oryx antelopes in Namibia, for example). In a Welsh conifer plantation, thermal-imaging drones were used to detect nesting nightjars, picking out their 40°C bodies against the colder ground – these birds are nocturnal, well camouflaged and easily disturbed, so notoriously tricky to study by traditional methods. In Sumatra and Borneo, thermal-equipped drones have counted orangutans and proboscis monkeys scattered through the forest canopy. RESEEDING HABITATS An Oxford start-up has used drones to sow grasses and trees over old Australian coal mines, and replace mangroves in Myanmar. After aerial surveys to locate suitable sites, biodegradable seed bombs were fired from mid-air. Theoretically, a team of two operators can…

It is time to wake up and smell the grass – to recognise that Britain is slumped, somewhat obliviously, in a blurry, lime-green hangover that’s been going on for so long that we no longer seem to recognise what’s not natural and normal. Protests this year have prompted concern, by scientists and campaigners, about how Britain cares for its half a million hectares of urban green land, and what we perceive as ‘nature’. With Britain having lost about 97 per cent – three million hectares – of its wildflower-rich grasslands since the 1940s, our closely strimmed parks, greens, school fields, university lawns, squares, landscaped grounds and sports fields could offer alternative refuge to declining wildlife. We have more than 84,000 hectares of publicly accessible urban green space, and 62,000 parks…

The Mara Triangle encompasses the area of the Maasai Mara National Reserve that lies west of the Mara River – about a third of the total protected area. It has been managed by the non-profit Mara Conservancy since 2001, with great success. Anti-poaching efforts are stringent (to date, rangers have arrested some 4,500 poachers and removed more than 56,000 wire snares); the impacts of tourism are mitigated by, for instance, limiting vehicles to five at off-road sightings; roads and ranger stations are spotlessly maintained; and relationships with local communities have been strengthened. maratriangle.org…

Children often question if you’ll get two worms by chopping one in half. It’s true that an earthworm’s brain and other vital organs are all at the head end, so if it is cut in two behind the swollen ‘saddle’ region, the front half of the worm may regenerate a tail. But the rear half will die. More primitive flatworms ( below ) have simpler anatomies, however. Splitting in two is how some of these species reproduce, and therefore dividing them can result in a pair of clones. Tiny marine flatworms are reportedly able to recover from strategically placed partial cuts, producing a two-headed (or two-tailed) worm. A Harvard University study of the snazzily named three-banded panther worm revealed last year that it can regenerate within eight days of being…

Spring in temperate climates is a carnival of colour. As days lengthen and temperatures rise, the electric-green of fresh foliage transforms the dull landscapes of winter. Yet several months later, those bright leaves have turned dark green, giving woods a duller appearance. Spring foliage is a magnet for a multitude of caterpillars and other insect larvae, which can’t wait to get their jaws on the soft and supple, cellulose-rich leaves. So, to repel this army of leaf-munchers, plants defend themselves by producing dark tannins. These bitter-tasting chemicals are a natural pest control. They become activated when the leaf is eaten, and are capable of damaging the mouth and stomach proteins of attacking insects. As summer wears on, the leaves get ever darker and more distasteful as tannins build up to…

Woodland wonders The Isle of Wight is a stronghold for red squirrels, with the Solent keeping the greys at bay. I grew up spending many a day playing in a wood attached to my grandparents’ property, with wildlife close at hand. Many years later, this acted as the catalyst that led to me becoming a wildlife photographer. This photograph was taken from a portable hide, in that same woods as I used to frequent – a wonderful, secluded location where I can sit and watch many species at close quarters. Stuart Shore, Ryde 1 Right place, right time During a family holiday at Zimbabwe’s Hwange National Park, we were sitting in a Land Rover near a water hole when a Bradfields hornbill came to settle on a log close by.…