12-15-18 The secret site in England where beavers control the landscape
I have gone back in time to a landscape not seen in this part of the world for the best part of 500 years. All around me are signs of intensive engineering – not by humans, but by beavers. Mark Elliott at the Devon Wildlife Trust is showing me round 2.8 hectares of wetland on the edge of Dartmoor, UK. In 2011 the trust released a pair of Eurasian beavers here. “They’re really busy at the moment,” he says. Before the release, the area was a scrubby woodland with a small stream running through it. “It wasn’t much good for anything else,” says landowner John Morgan. But the beavers quickly got busy, building a lodge, deepening the pond around it and damming the headwaters of the stream. Elliot and his colleagues collated the results of the beaver introduction earlier this year, including the huge improvement they’ve had on flood management. On the surrounding countryside, rain (of which there is a lot) runs quickly off the land, surging into rivers and causing flash floods. But on beaver territory the water is now held up in the ponds and flows out at a much more leisurely pace. “It takes days or weeks,” says Richard Brazier at the University of Exeter, one of the project’s lead scientists. Even during a downpour the outward flow of water barely rises above baseline. Hardly anybody lives around here so flooding isn’t an issue. But elsewhere it is a serious and growing menace. The UK has earmarked £2.5 billion a year to upgrade its flood defences. Judging from the research done here, beavers could be part of the solution. The team have kept the location of the project secret to avoid people interfering. Some people are just keen to see the beavers for themselves, but others may wish to sabotage the trial because they oppose the reintroduction of a “nuisance” species. Beavers are known as ecosystem engineers. I can see that every inch of the site has signs of ceaseless beavering: felled trees, gnawed stumps, chewed logs and sticks stripped of bark. The stream has been turned into a series of 13 large pools held back by dams made of sticks, mud and grass. The oldest dam resembles a Neolithic earthwork, several metres across and grassed over. It holds a serious amount of water with over a million litres behind dams on the site.
12-14-18 Endangered northern bettongs aren’t picky truffle eaters
The marsupials’ varied diet could help safeguard some of Australia’s fungi and forests. A small endangered marsupial with a taste for truffles may be a linchpin in one kind of Australian forest — and the evidence is in the animal’s poop. Northern bettongs feast on truffles, the meaty, spore-producing parts of certain fungi. Plenty of animals eat a selection of these subterranean orbs from time to time. But analyses of the scat from northern bettongs (Bettongia tropica) reveal that the marsupials eat truffles from a wider diversity of fungi species than other critters, including some that no other animals appear to favor, researchers report November 22 in Molecular Ecology. That’s an important role because these truffle-producing fungi form beneficial relationships with tree roots, helping trees pull nutrients and moisture from soil. “There's been a whole raft of published studies showing that those fungi give plants an edge,” says Andrew Claridge, an ecologist for the New South Wales National Parks and Wildlife Service in Queanbeyan who wasn’t part of the study. Australia’s eucalyptus forests host hundreds, or possibly even thousands, of truffle fungi species, says study coauthor Susan Nuske, an ecologist at the Swedish University of Agricultural Sciences in Umeå. Different species seem to be specialized to associate with particular trees or perform certain roles, so maintaining that diversity is key. By spreading truffles’ spores via scat, bettongs help keep the fungal community diverse and, by extension, the forest healthy, say Nuske and her colleagues.
12-14-18 Counting the breaths of wild porpoises reveal their revved-up metabolism
In Danish waters, these small cetaceans have metabolic rates more than double those of humans. By counting harbor porpoise breaths, researchers have come up with a new way to judge the animals’ hard-to-measure metabolism. The trick shows that the animals can burn energy more than twice as fast as humans. Researchers analyzed the several thousand puff-huff respiratory sounds recorded per day from each of 13 harbor porpoises swimming freely in Danish waters. Including just everyday staying-alive body processes plus hunting and other activities, the animals’ average total energy use ranged from 7.8 to 31 megajoules per day, researchers report December 6 in the Journal of Experimental Biology. The five adult porpoises (Phocoena phocoena) studied averaged 21.7 megajoules per day. A typical human weighing about as much as a full-grown porpoise, however, needs only about seven to nine megajoules of energy daily, says study coauthor Peter Teglberg Madsen, an eco-physiologist at Aarhus University in Denmark. Madsen says the animals’ high energy needs in the chilly waters close to Danish shores leave him “somewhat worried.” Harbor porpoises there depend on small fish, even down to pinkie finger–sized ones. But to survive with such a high metabolic rate on small prey demands steady hunting. And Madsen fears that increasing human disruptions in the ocean are making that difficult for the ocean mammals (SN: 2/13/18).
12-12-18 Australia’s ‘marsupial lion’ was a meat-ripping, tree-climbing terror
The most detailed reconstruction yet of Australia’s extinct “marsupial lion” shows it was unlike any animal living today, shredding its prey like a Tasmanian devil, biting like a lion, and climbing like a koala. The first partial remains of the fearsome predator – which went extinct about 45,000 years ago – were discovered in Victoria in the 1850s. British naturalist Richard Owen named it Thylacoleo carnifex – meaning “meat-cutting marsupial lion” – based on its large blade-like teeth and cat-like skull. Other remains of T. carnifex were found in the 1960s and 70s, but it was only in 2002 that the first complete skeleton was discovered in a cave beneath the Nullarbor Plain in Western Australia. In 2005, another two mostly complete skeletons were found in a cave in Naracoorte, South Australia. Since then, Rod Wells at Flinders University and his colleagues have carefully studied the skeletons to better understand the mysterious creature. Their reconstruction shows that T. carnifex would have measured over a metre long and over half a metre tall while standing on all four feet, with a weight of about 100 kilograms. “It was probably the size of a big pig,” says Wells. Like other marsupials, it carried its young in a pouch. Comparisons with living Australian marsupials suggest that T. carnifex was most similar in appearance to the Tasmanian devil, but would have been about 10 times bigger. It had the same stiff back and strong, rigid tail that Tasmanian devils use for balance while tearing apart prey with their paws and teeth, says Wells.
12-12-18 Endangered relative of the hedgehog may be thriving in Vietnam
The Hainan gymnure is a bizarre, poorly understood hedgehog-like mammal, previously thought to live only on the island of Hainan off China’s southern coast. But recently, scientists found the mammal in Vietnam – hundreds of kilometres away – where it may actually be relatively common. Gymnures and moonrats are close relatives of the winsome spiky hedgehogs. But, lacking prickles, they resemble rats or opossums. They often reek strongly of garlic or ammonia due to their potent, territory-marking scent glands. Native to Southeast Asian forests, the animals are nocturnal and reclusive. The Hainan gymnure (Neohylomys hainanensis) is the most elusive of all. “In the world’s scientific collections, there are only a few specimens of N. hainanensis,” says Alexei Abramov, a zoologist at the Russian Academy of Sciences in Saint Petersburg and lead author on the study. “I know of ten specimens.” Earlier this year, Abramov and his colleagues conducted a small mammal biodiversity survey in Cao Bang Province in northern Vietnam. During this survey, the team obtained five gymnures from local villagers. After measurement of their physical features, the team identified the gymnures as the rare Hainan species, suggesting that the island dweller is more widespread than realised. “There’s been work done on the mammal fauna of Vietnam in the past, and these are apparently not particularly rare animals,” he says, offering that gymnure preference for earthworms and insects rather than typical bait may have kept them undetected. The gymnure’s presence in Vietnam also implies that Hainan and Vietnam were physically connected millennia ago, when glacial expansion lowered sea levels by 120 metres.
12-11-18 The beauty of the Christmas Bird Count
Counting birds for science is one of the most fulfilling ways to end the year. The ash tree I'm anchored to is laced with poison ivy vines, one as thick as my arm. The childhood adage, don't be a dope, don't touch the rope, is loud in my mind because although I'm no "dope" I'm definitely touching the rope — the ash is the only thing keeping me from falling into the icy creek below. I embrace the ash with my left arm and through a layer of fresh snow, I dig in and plant myself. With my right hand I bring binoculars to my eyes and scan the plowed cornfield beyond the creek for movement. I'm looking for a flock of Horned Larks, small little brown birds with two tufts of feathers on either side of their head that resemble horns. Against a backdrop of tilled earth they are cryptic but, lucky for me, it snowed last night and not much can stay hidden on the field. My desire to find a flock of larks sprouts from a kernel of hope that a Lapland Longspur might be embedded among them, or maybe a Snow Bunting. Both birds are as exquisite-looking as they sound. The longspur is sparrow-like, but fairer, with a sweet round face. The bunting is white and in its winter plumage its cheeks are decked out in chic buff-colored feathers. The cornfield is empty. There are no chattering larks, no longspurs mixed in, and there are certainly no buntings. The field is host only to a rolling wind that carries with it a chill of -10 degrees Fahrenheit and the smell of Christmas in the country — a peppery mix of soot, smoke, and decay. My eyes sting. It's been a while since I've blinked. I let my binoculars hang at my side for a moment. It's the last day of the year and I'm looking for birds in subzero temperatures. Of course, I am. It's the annual Christmas Bird Count. The bird count is important to me — I've done it every year for the past four years. Nothing can stop me, not the cold, rain, the flu, or even poison ivy. Birders — don't call us birdwatchers — are a robust and growing group of professionals, enthusiasts, students, and everything in between. In the U.S. we are 45 million strong and along with other wildlife-lovers and conservationists, we contributed close to $80 billion to the U.S. economy in 2016. The data collected by citizen scientists like me during the Christmas Bird Count helps ornithologists, biologists, environmental scientists, analysts, and others understand species diversity, movement, and dispersal. The information also helps them gauge how birds are surviving a warming planet. Spoiler alert: It's not going well for coastal species. A bunch of other species are in decline, too.
12-10-18 City living makes urban male frogs far more attractive to females
Male frogs that live in cities make more complex mating calls than their forest-dwelling cousins, and that makes them much more attractive to female frogs. As animals move into urban environments, they face different pressures from natural selection, resulting in rapid evolution of different behaviours. Previous research has found that birds, frogs and grasshoppers sing or call differently in noisy urban areas, but few studies have addressed in detail how this affects their needs to attract a mate and avoid predators and parasites. Male túngara frogs gather at night in puddles to call and attract females. The main part of their call, the “whine”, sounds like a sci-fi laser beam, but some add elements called “chucks”, which sound like very short duck quacks. However, making a more elaborate call raises the risk of attack by bats or biting midges. Wouter Halfwerk of the Free University Amsterdam and colleagues recorded males in urban and forest locations in Panama. The urban males called more often and made more complex sounds than the forest males, with more and louder chucks. These complex calls proved to be irresistible to females. When the researchers played recordings of an urban male and a forest male from two speakers, three quarters of the females approached the one playing the urban call. To explain why a different call evolved in the city, the researchers tried playing the same recorded call from a speaker in different locations. At urban sites, the calls attracted fewer female frogs, bats and midges. This suggests that in cities, the pressure to attract mates is stronger and the pressure to avoid predators and parasites is lower.
12-10-18 Amount of deep life on Earth quantified
Scientists have estimated the total amount of life on Earth that exists below ground - and it is vast. You would need a microscope to see this subterranean biosphere, however. It is made up mostly of microbes, such as bacteria and their evolutionary cousins, the archaea. Nonetheless, it represents a lot of carbon - about 15 to 23 billion tonnes of it. That is hundreds of times more carbon than is woven into all the humans on the planet. "Something like 70% of the total number of microbes on Earth are below our feet," said Karen Lloyd from the University of Tennessee at Knoxville, US. "So, this changes our perception of where we find life on Earth, from mostly on the surface in things like trees and whales and dolphins, to most of it actually being underground," she told BBC News. PROF Lloyd is part of the Deep Carbon Observatory (DCO) project, a near-decade long effort to identify how the ubiquitous element is cycled through the Earth system. The consortium is reporting its latest discoveries here at the American Geophysical Union (AGU) annual Fall Meeting in Washington DC. The mass numbers it quotes can only be a rough estimate. They are derived from multiple studies that have dug or drilled several kilometres into the crust, both on the continents and at sea. Scientists will routinely pull up rock and other sediment samples and count the number living cells in a given volume. The DCO teams have taken these inventories and used models to construct a broader picture of Earth's total biomass.
12-7-18 The bluebirds’ best friend.
Al Larson is the bluebirds’ best friend. Since 1978, the 96-year-old former sawmill worker has built and maintained some 350 nest boxes across southern Idaho for western and mountain bluebirds, helping the species rebound from near-extinction. He started nest building to keep himself busy in retirement, and now checks in on the rustic abodes every nine days, banding any residents. This year, he’s banded more than 900 bluebirds. “I got carried away,” Larson said. “I kept adding more boxes, and these birds responded.”
12-6-18 Here’s how geckos (almost) walk on water
High-speed video reveals the physics of how the animals move almost as fast in water as on land. Add water aerobics to the list of the agile gecko’s athletic accomplishments. In addition to sticking to smooth walls and swinging from leaves, geckos can skitter along the surface of water. By slapping the water with all four limbs to create air bubbles and exploiting the surface tension of water, the reptiles can travel at speeds close to what they can achieve on land, according to a new analysis of high-speed video footage described December 6 in Current Biology. In the world of water walkers, geckos occupy an awkward intermediate turf, says study coauthor Jasmine Nirody, a biophysicist at Rockefeller University in New York City and Oxford University. Small insects like water striders use surface tension, created by water molecules sticking together, to stay afloat. Bigger animals like basilisk lizards slap the surface of the water, creating air pockets around their feet that reduce drag and keep the lizards mostly above the water’s surface. But an animal needs to be fairly large to generate enough force to hold itself out of the water using that strategy. “Geckos fall smack-dab in the middle” size-wise, Nirody says. “They shouldn't really be able to do this at all.” And yet, when her colleague Ardian Jusufi of the Max Planck Institute for Intelligent Systems in Stuttgart, Germany, was vacationing in Singapore, he noticed small geckos skittering across the surface of puddles. Back in the lab, the team filmed eight flat-tailed house geckos (Hemidactylus platyurus) crossing a tank of water, then slowed the footage to get a closer look at the action.
12-6-18 Geckos sprint across water on air bubbles they make with their legs
Flat-tailed house geckos can skitter across the surface of water – and now we know how they do it. They keep their upper body in the air by slapping hard on the water and creating pockets of air that help them stay afloat. Though they can swim, running across water is a useful way for them to escape quickly when they are threatened. Jasmine Nirody at The Rockefeller University in New York and her team investigated how geckos cross water after her colleague visited Singapore during monsoon season and saw the behaviour in the wild. “To us this was really shocking because when you think about the things that walk on water, you think of these really small insects that can walk using surface tension. Or large bipedal basilisk lizards that generate so much force on the water that they can support their body weight,” she says. “These guys lie smack dab in the middle.” They took high-speed video of 8 geckos doing 63 runs across a 35-centimetre-long basin filled with water. They found that geckos keep their heads 13.4 millimetres above the surface, on average, while their tails remain in contact with the water. The geckos whirl their front legs in a circle – a little like the way a cartoon character might run. Part of this circle passes through the air and part of it under the water, which helps creates an air pocket that holds the gecko up. They then cycle their back legs to produce forward motion. “They are partially hydroplaning,” Nirody says. The team also found that geckos can lift up to 72 per cent of their body length out of the water, and that they have superhydrophobic skin that repels water. Both of these factors help reduce drag.
12-6-18 Parrots are clever because their brains evolved the same way as ours
Parrots are intelligent birds capable of complex cognition, and it turns out that the genes that play a role in their brain development are similar to those that evolved to give humans large brains. “It’s a surprise in the sense that these animals are so different from humans, but it’s also satisfying in that you might predict that since they evolved similar traits, they have some similar mechanisms,” says Claudio Mello at the Oregon Health & Science University. Parrots can produce complex vocalisations and they’re highly social, a lot like humans. To learn more how these birds’ brains develop, Mello and his team compared the genome of the blue-fronted Amazon parrot with that of 30 other birds. They found that regions of the parrot genome that regulate when and how genes for brain development are turned on are the same as those found in humans. These so-called ultra-conserved elements evolved in both species at different times, but with similar results. “These define how the brain grows and how many cells are built,” Mello says. “Humans ended up with bigger brains and more brain cells and more cognitive traits – including language – than primates. Parrots have bigger brains than other birds and more communication skills, and they have similar conserved elements that set them apart.” Mello says that when these regulatory regions of the genome are disrupted in humans, they are known to be associated with cognitive disabilities such as autism, developmental delays and language deficits. The team also found 344 genes associated with parrot lifespan. Parrots live far longer than would be expected based on their body size and metabolism, some even lasting into their 80s. The genes Mello and his team found that are associated with parrot lifespan support DNA damage repair, slow down cell death due to stress, and limit cell overgrowth and cancers.
12-5-18 Pea aphid youngsters use piggyback rides to escape a crisis
Hitching a ride on reluctant adults helps babies survive after fleeing a grazing animal. First it’s mammal bad breath. Then it’s babies pestering for piggyback rides. A near-death experience is tough on pea aphids. When warm, moist breath signals that some cow or other giant is about to chomp into foliage, tiny green aphids feeding on that foliage drop toward the ground by the hundreds (SN Online: 8/10/10). “It literally rains aphids,” says ecologist Moshe Gish, who in 2010 described the breath cue. Now Gish and Moshe Inbar, both at the University of Haifa in Israel, describe what pea aphids (Acyrthosiphon pisum) do after they hit the ground. There’s “a climbing frenzy,” Gish says. “Frantic” newborns scramble onto adults for a piggyback ride to safety. Open ground may be a better bet than certain death in cow cud. But exposure still brings risks from other predators as well as dehydration or even starvation if the aphids can’t find another plant to suck sap from. In a lab setup, hitchhiking got very young aphids safely across open ground about four times faster than scrabbling to safety on their own, the researchers found. These newborn aphids, not even 12 hours old, were not just seeking some object to clamber onto. They soon lost interest if presented with beads or dead adults but held on to live grown-up aphids in motion, the researchers report December 6 in Frontiers in Zoology. When catching a ride, kinship didn’t seem to matter. Closely related or not, most adults resisted vigorously, bobbing heads or rears up and down. Some just lowered that head or rear and waited. In the end, only about 5 percent of youngsters got their much sought-after piggyback ride.
12-5-18 Rats and pigeons 'replace iconic species'
The modification of land for farming and building cities is favouring the same species everywhere, according to a new study. Animals like rats and pigeons are taking over from less common ones, which can survive only in certain habitats, say scientists. Researchers looked at 20,000 animals and plants in 81 countries. They found that species occupying a large area tend to increase in places where humans use the land. However, fauna and flora that occupies a small area is lost. "We show around the world that when humans modify habitats, these unique species are consistently lost and are replaced by species that are found everywhere, such as pigeons in cities and rats in farmland," said Dr Tim Newbold, a research fellow at University College London. Rats, mice, sparrows and pigeons are examples of species with wide ranges that do well when natural habitats are replaced with farmland and cities, he said. However, the "narrow-ranged losers" include animals and plants which may have great cultural value, such as rhinos and tigers. Co-researcher, Prof Andy Purvis of the Natural History Museum, London, compared the changes in biodiversity to what is happening on the British high street."As small, independent retailers are going out of business, large chains dominate," he said. "It makes all towns look the same, and it's less easy to tell where you are. Likewise, people are affecting nature everywhere they go, and everywhere there are localised species which are struggling to make a living." (Webmaster's comment: A perfect example of evolution at work.)
12-5-18 Ash dieback: ash woodlands 'may flourish once again'
Scientists say there is hope that some ash forests will be able to survive a devastating tree disease. Surveys around Europe reveal mortality rates from ash dieback as high as 70% in woodlands and 85% in plantations. A previous study found almost all ash trees could be wiped out. The disease has swept across Europe over the past 20 years, causing widespread damage to woodlands. In many cases the fungus will eventually kill infected plants. "Although the numbers seem grim, the percentage of trees that are still alive is encouraging from a long-term perspective," said Prof Richard Buggs, of Royal Botanic Gardens Kew and Queen Mary University of London. "If this survival is due to heritable resistance, then conservation policies targeting breeding programs or natural selection may allow ash populations to flourish once again." The researchers pulled together surveys of ash dieback across Europe, including England, Ukraine, Scandinavia and the Baltic States. They found that even in forests that had been exposed to the disease for 20 years, not all trees were lost. "Although we may witness terrible devastation of ash woodlands in Europe, our grandchildren may see viable ash populations," said the researchers. There is typically a delay of 10 years from the disease entering the country to the widespread death of ash trees. This means that in the UK, the full extent of ash dieback will not become clear until 2022.
12-4-18 Saving the last West African giraffes in Niger
For almost 50 years, the highly threatened West African giraffe has been absent from Niger's Gadabedji Biosphere Reserve. Illegal hunting, climate change and habitat loss have all contributed to the population's decline. An ambitious conservation initiative has now re-introduced eight giraffes into the reserve, in the first conservation effort of its kind for the West African subspecies. Under the initiative, spearheaded by the Nigerien authorities, the eight giraffes were captured in the country's Giraffe Zone, a government-defined region approximately 60km (37 miles) south-east of the capital, Niamey. Until this move, the world's last West African giraffes had only been found in and near this Giraffe Zone. There, West African giraffes share their habitat with local communities, and compete with them for space and natural resources. The animals face a number of threats, including human population growth, hunting and agricultural encroachment. Giraffes have now started to migrate out of the Giraffe Zone as a result of the growing population of both humans and giraffes themselves. As a result, the animals have come into conflict with humans who are not used to their presence, and also stray into restive areas on the border with Mali. After the eight giraffes were captured, they were secured with ropes and herded into trailers. They were then put in a holding pen for more than three weeks to prepare them for the long journey to come. The population of giraffes has dwindled across Africa over the past 30 years, according to the Giraffe Conservation Foundation (GCF). In West Africa, the regional subspecies was once common in many countries, including Nigeria, Mali, Mauritania and Senegal, but now only exists in Niger. In the mid-1990s there were only 49 West African giraffes left in the wild. As a result, the subspecies was listed as endangered on the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species in 2008.
12-4-18 World's strangest sharks and rays 'on brink of extinction'
Some of the world's most unusual sharks and rays are on the brink of extinction because of threats such as commercial fishing, scientists have said. A shark that uses its tail to stun prey and a ray half the length of a bus are on the list of 50 species. The scientists say sharks have a bad image and people do not understand how important and threatened they are. And losing even one of these "living fossils" would wipe out millions of years of evolutionary history. "The biggest myth around sharks is definitely the perception that they are dangerous, that they are man-eating machines - they're not," marine biologist Fran Cabada told BBC News. "There have been some negative interactions recorded but they are very infrequent and they're not intentional." This is the first time sharks, rays and chimeras (fish with cartilage in place of bones) have been assessed for the Edge (Evolutionarily Distinct and Globally Endangered) of Existence programme. Most sharks are at the top of the food chain, which makes them crucial to the health of the oceans. Losing them would have a big impact on other fish populations and, ultimately, human livelihoods. "They have very few relatives on the tree of life, so they are very unique and losing them will actually represent a big, big loss," said Fran Cabada. The assessment found fishing, both targeted and accidental, was to blame for the steep decline in many of these populations, together with habitat loss due to coastal development, degradation of mangrove forests, water pollution and trawling. "The Edge sharks and rays list comprises some of the most interesting and unique fish we have on this planet," said Dr Matthew Gollock, of ZSL. "The modern extinction of a single species from this list would cause the loss of millions of years of evolutionary history."
12-4-18 Rebel honeybee workers lay eggs when their queen is away
The rebel workers are also more likely to infiltrate other colonies to have offspring. Even honeybee queens have rebellious kids. In a colony of European honeybees (Apis mellifera), only the queen lays eggs that hatch into female workers who maintain the hive and nurse the young. But at times a colony experiences periods of queenlessness, when the old queen has left and a new one isn’t ready. Some of the queen’s left-behind worker daughters seize this chance to lay their own eggs — and sometimes in an entirely new colony, finds a study published online October 31 in Ecology and Evolution. The workers’ opportunistic egg-laying behavior was discovered in 2012 by researchers led by evolutionary biologist Karolina Kuszewska of Jagiellonian University in Kraków, Poland. With no queen around to release chemicals that stunt workers’ ovarian growth, these “rebel workers” can lay eggs. Since rebel workers still do not mate as a queen bee would, they produce only sons that live only to mate. A departed queen’s replacement comes from a group of daughters born to fight one another until one survivor becomes the new queen. Rebel workers are also more adventurous than normal worker bees, the new study shows. When the researchers tracked bees that were raised without queens, 21 to 39 percent of rebel workers flew to one of dozens of other colonies, compared with 3 to 8 percent of normal workers. No surprise: Those rebel workers were also more likely to infiltrate colonies that had no queen.
12-2-18 The Ugandan love of grasshoppers - and how to harvest them
It is grasshopper season in Uganda, where they are seen as a nutritious delicacy - either boiled or deep-fried. They are so popular that some are worried about declining harvests, as the BBC's Patience Atuhaire reports. It is dusk. Rusty oil barrels are lined up in rows. Wooden scaffolding holds up unpainted iron sheets. The blindingly bright lights are rigged up as if for a sports stadium. But the four young men are not preparing to play football, they are here to catch grasshoppers. At this time of year, during the rainy season, the scene is repeated in many towns across the country. "When the season starts, we watch the cycle of the moon, and prepare. [They tend to come out at full moon]. We also keep hoping for rain. The larger numbers appear when it has rained," says Quraish Katongole, one of Uganda's most experienced grasshopper trappers. He is the chairman of a group that coordinates the grasshopper trade around the country. As his workers set up the last of the barrels at a trapping site here on the edge of Masaka town, he heads off to supervise work at other locations. As it grows darker, the slim-bodied nocturnal insects start to swarm around the lights. Most of them are green, but there are sprinklings of ashy-brown and golden-brown. The trappers burn fresh grass and the rising smoke makes the insects dizzy. The grasshoppers smash against the iron sheets, falling straight into the drums. It sounds like fat raindrops on a tin roof. And as the numbers increase, it becomes a steady downpour. Women, schoolgirls still in their uniforms, even children, scour the bushes surrounding the traps, picking up the escapees that have avoided the barrels, before they can burrow further into the greenery.
12-1-18 Nation's botanical treasure troves 'under huge threat'
A million plants from every corner of the globe are tucked away inside the cabinets that line the walls. It's a scientific collection that goes back centuries, gathered by the likes of Carl Linnaeus, the "father of taxonomy", and Charles Darwin. They could have had no inkling that pressed, dried collections of plants would have modern uses in assessing extinction risks. Estimates suggest one in five of the world's plant species is threatened. Collections of pressed, dried plants are an important "living" resource, say scientists. "People think of Herbaria as being dead, old plants and not relevant," says Kathy Willis, Professor of Biodiversity at the University of Oxford. "It's living in the sense that the information it has is as relevant, if not more relevant, to society presently than it was in the past." A wealth of botanical treasures can be found at the Oxford University Herbaria, from the bark and seeds of rare African trees to plants collected at the height of the Irish potato famine. Some are mounted on medieval wallpaper; others bear the signature of famous plant collectors and scientists. Each specimen has a story to tell; speaking not just of history but of science. As permanent scientific records of where plants have existed on the planet at a specific time, they can be used to investigate and record plant evolution and diversity. The UK is a powerhouse where Herbaria are concerned, holding about 20 million of the 300 million specimens worldwide. However, the collections are largely tucked away in cupboards, rather than digitised and available to all.
12-1-18 TEDWomen: Vibrations offer new way to track elephants
Researchers have come up with a new way of tracking elephants, via the vibrations that the animals make. Scientists Dr Beth Mortimer and Prof Tarje Nissen-Meyer discovered that elephants generate vibrations through their normal movements and through vocalisations, known as "rumbles". These can be measured by techniques usually used for studying earthquakes. The Oxford academics spoke about their research at the TEDWomen conference currently under way in California. They explained how they measured the seismic waves that could travel nearly four miles through the ground. They recorded the vibrations generated by wild elephants in Kenya while walking and calling, using instruments known as geophones. Seismological modelling software that incorporates the local geological information was combined with computer algorithms to produce accurate estimates of the seismic waves produced by elephants. They filmed the animals during recordings and later synchronised the two to allow them to visually confirm that the vibrations originated from elephants. They found that other noise and soil type affected their ability to distinguish the patterns over long distances. Vibrations travel farther through sand than through hard rock and also when little other noise is present to interfere. Finding out what elephants are doing, even when they are some distance away, could help fight poaching in real time as well as offering insights into their behaviour, they said. Their findings were published in a paper for journal Current Biology earlier this year. Save The Elephants' chief executive, Frank Pope said of the research: "Legends and folklore have long spoken about the way elephants cannot only communicate across long distances, but also detect other events that shake the ground like far-off thunder.