5-28-21 Drones and live-streams: How tech is changing conservation
Drones, satellites and laser sensors. It sounds like the tech of an action-packed spy thriller. Not things you might typically associate with protecting animals. According to a report by the World Wildlife Fund for Nature (WWF), the planet's wildlife population has plummeted by 68% since 1970, with threats including things like poaching and loss of habitat. But around the world, animal conservation has now evolved so it's not just rangers and anti-poaching groups monitoring the wildlife of our world. So just how is technology helping to modernise animal conservation? The most recent eye-catching example of technological innovation can be found in the Balule Nature Reserve in South Africa, part of the huge Kruger National Park. Camera phones mounted in protective cases streamed images of animals to people worldwide. Thousands, sat comfortably at home, became virtual rangers with this anti-poaching pilot project, Wildlife Watch, by Balule, Samsung and Africam. Viewers were able to report suspicious activity - things like seeing fence lines cut or hearing gunshots - and alert rangers to the possibility of poachers and trapped animals needing rescue. For Leitah Mkhabela, a member of the park's all-female anti-poaching unit known as The Black Mambas, creative use of technology can make a big difference. "The live-stream is a great tool that helps us monitor even more areas in real time. The public helps us with watching and listening for anything suspicious," the 28-year-old tells Radio 1 Newsbeat. She describes one such incident. "People saw something, suspected it and then reported it. When we went, a lion was freezing and the first line of the fence was broken." "Once poachers become aware that there could be more cameras in the bushes, they'll be worried as we have so many eyes monitoring. "It will definitely help chase them out." And this live-stream isn't the only innovation.
5-27-21 Monkeys can change their accent to communicate with another species
Have you ever adopted a local accent so people can understand you better? Some tamarin monkeys in the Amazon rainforest do something similar if they share living space with a closely related species. Red-handed tamarins seem to have changed their calls to sound more like those of pied tamarins, so that the two species can warn each other away from their respective territories. Tamarins use long, high-pitched whistles to alert other individuals to their presence and deter them from getting too close. “Nobody wants to get into a fight. You scream and shout a bit first to warn each other,” says Jacob Dunn at the University of Cambridge, who was involved in the research. “It’s a means of maintaining space between groups.” Pied tamarins (Saguinus bicolor) have a pure-sounding note, while in most of the Amazon, the calls of red-handed tamarins (Saguinus midas) are similar but span a wider frequency range. Tainara Sobroza at the National Institute of Amazonian Research in Manaus, Brazil, wondered if the two species’ calls would sound even more similar in the patch of forest where they overlap. Her team recorded calls from the monkeys at 15 sites that were either in overlapping habitat or in places where only one species lived. In the shared territory, although the pied tamarins hadn’t changed their calls, the red-handed tamarins had shifted to a slightly purer whistle, a difference that could be measured when the sounds were translated into a spectrogram, a visual representation of sound. “It is like an accent because they’re giving the same message, but saying it in a slightly different way,” says Dunn. The change in calls is seen only among tamarins living in pristine old-growth forest, not in places where trees have previously been cut down and the regrowing vegetation is less mature, with fewer thick tree trunks, and so transmits sound differently.
5-26-21 Pesticide-resistant blood-sucking lice threaten wild and farmed fish
Efforts to rid fish farms of blood-sucking aquatic lice by using chemical pesticides have ended up giving the pests increasing resistance, leading to widespread infestations in the north-eastern Atlantic Ocean. Somewhat like ticks on land animals, salt-water-living salmon lice (Lepeophtheirus salmonis) hook on the skin of salmonids (mainly salmon and sea trout), feeding on their blood and mucus and creating sores that can get infected and even cause death. In natural conditions, lice numbers drop over winter as trout return to fresh water and salmon disperse into the cold ocean waters. But intense fish farming has provided the parasites abundant, year-round hosts which allow them not only to thrive in winter, but also to mutate rapidly to avoid pesticides. “They have a short generation time and high numbers,” says Helene Børretzen Fjørtoft at the Norwegian University of Science and Technology in Aalesund. “It’s like with covid-19 – more hosts facilitates more pathogens or parasites, which in turn increases the chance of mutations.” Now these mutating lice have spread their resistant genes from Scandinavia to Greenland, and even up into Iceland where farmers don’t use chemical pesticides. To trace the effects of organophosphates and pyrethroids – chemicals commonly used to control salmon lice in the past two decades –Fjørtoft and her colleagues ran genetic analyses on about 2000 lice collected from farmed and wild fish across the northern Atlantic between 2000 and 2017. Looking for specific genes associated with resistance to each chemical, they were able to map out how quickly lice populations mutated – usually within a few years – to survive pesticide treatment. They found that more than 50 per cent of the lice sampled around fish-farming regions were resistant to both chemicals, says Fjørtoft. In some areas, they had a hard time finding any lice that hadn’t mutated towards resistance to at least one chemical.
5-26-21 Scottish blue tits mostly survive on food from garden bird feeders
Garden bird feed is the most common food source found in a sample of blue tit faeces collected across Scotland. Garden bird feed is the most common food source found in a sample of blue tit faeces collected across Scotland. Bird feeding is a common pastime and often encouraged by many conservation organisations. Jack Shutt at Manchester Metropolitan University, UK, and his colleagues have investigated how popular garden bird feed is among blue tits (Cyanistes caeruleus) in Scotland. They analysed 793 samples of blue tit faeces, collected from nest boxes at 39 points along a 220-kilometre-long study area running from Edinburgh to Dornoch, a town in the Highlands of Scotland. Using DNA analysis, they first confirmed the faeces were from blue tits and then worked out what the birds were eating. They found 53 per cent of the samples contained DNA evidence of garden bird feed, with peanuts in 49 per cent of samples – the single most common food. In comparison, the most common natural prey found in the faeces was the moth Argyresthia goedartella, in 34 per cent of samples. The study suggests that the quantity of bird feed detected in faeces decreases as the distance from houses with feeders increases. But the researchers still found bird feed in birds that live far away from urban areas – the furthest they detected bird feed in faeces was 1.4 kilometres away from the nearest house. It seems that blue tits go to surprising lengths to access feeders if they live in remote areas, says Kate Plummer at the British Trust for Ornithology, who wasn’t involved in the study. “We collected samples from urbanised areas like Edinburgh, Perth and Inverness, which are quite big cities, but also through the middle of Cairngorms national park, which has almost no population at all,” says Shutt.
5-26-21 Tasmanian devils born on Australian mainland after 3,000 years
Tasmanian devils have been born on the Australian mainland for the first time in thousands of years. Conservationists introduced the species back into a sanctuary north of Sydney in late 2020. Now, around 3,000 years after the marsupials vanished from the mainland, the first joeys have been born in the wild.
5-25-21 Gray wolves scare deer from roads, reducing dangerous collisions
In Wisconsin counties with wolves, deer-car accidents dropped, saving millions of dollars. Gray wolves help keep North America’s deer populations in check, and by doing so, may provide an added benefit for people: curbing deer-vehicle collisions. In Wisconsin counties where wolf populations returned, the number of such collisions dropped in each area by 24 percent on average, scientists report online May 24 in the Proceedings of the National Academy of Sciences. Economist Jennifer Raynor and colleagues analyzed data on wolf populations, deer populations and deer-vehicle collisions for 63 counties in Wisconsin from 1988 to 2010. In the 29 counties that had wolves, the predators thinning deer populations contributed about a 6 percent reduction in deer-vehicle collisions. The rest of the decrease, the team proposes, was due to the wolves’ presence near roads, which they use as travel corridors, creating a so-called “landscape of fear” that keeps deer away. That suggests that recreational hunters wouldn’t replicate wolves’ impact by simply culling the same number of deer, the researchers say. The average drop of 38 deer-vehicle collisions per year in counties with wolves translates to an estimated $10.9 million in savings each year across the state, the team found. For comparison, the state paid about $3 million over the last 35 years to compensate for wolf damages. There may be other economic benefits not measured by the study such as reductions in damage to agriculture by deer and in Lyme disease frequency, says Raynor of Wesleyan University in Middletown, Conn (SN: 11/15/18). “The most interesting thing to me about choosing Wisconsin as a case study is that this is a human-dominated landscape,” Raynor says. Similar analyses could guide management decisions where potential wolf habitats overlap with heavily populated areas, such as in the northeastern United States, she and colleagues propose.
5-22-21 Salmonella: CDC urges Americans not to kiss chickens amid outbreak
The US Centers for Disease Control and Prevention (CDC) has urged people to refrain from kissing live poultry amid an outbreak of salmonella. The CDC and public health officials are investigating salmonella outbreaks after 163 people were reported ill in 43 states. The infections have been linked to contact with backyard poultry. "Don't kiss or snuggle the birds, as this can spread germs to your mouth and make you sick," the health agency said. It warned that poultry, like chicken and ducks, can carry salmonella germs even if they look healthy and clean, and these germs can easily spread in areas where they live and roam. Infection can cause fever, diarrhoea, stomach pain and vomiting. Most people recover without treatment, but more severe cases can cause death. According to the CDC, one-third of the people reported ill in the recent outbreaks have been under the age of five. Some 34 people have been taken to hospital since mid-February, but no deaths have been reported. The CDC's advice also includes washing hands after coming into contact with poultry, and preventing children from touching the birds. It estimates that salmonella bacteria - which can be found in raw or undercooked meat, eggs or other food products - causes about 1.35 million infections in the US every year, and 420 deaths. The CDC is the US public agency in charge of issuing health advice; last week for example, it changed the guidance on face masks, saying that people who had been fully vaccinated against Covid-19 no longer needed them in most places.
5-21-21 Urchin mobs team up to butcher sea stars that prey on them
The spiny invertebrates pin the sea stars’ arms in an overwhelming predator-prey role reversal. Sea urchins are underwater lawnmowers, their unabating, vegetarian appetites capable of altering whole nearshore ecosystems. But the spiny invertebrates will also sink their teeth into something a bit more challenging — and dangerous — new research suggests. In a first, researchers recently discovered urchins attacking and eating predatory sea stars. The observations flip a classic predator-prey script, researchers report in the June Ethology. In 2018, marine behavioral ecologist Jeff Clements and his colleagues were at the Kristineberg Marine Research Station in Fiskebäckskil, Sweden, studying common sun stars (Crossaster papposus). At one point, Clements wanted to separate one of the sun stars for a short while and needed aquarium space. He placed the starfish in a tank containing about 80 green sea urchins (Strongylocentrotus droebachiensis). “I thought, ‘Okay, there’s a bunch of sea urchins in there, these guys are predators of urchins, nothing’s gonna happen,’” recalls Clements, of Fisheries and Oceans Canada in Moncton. The urchins, he says, hadn’t eaten anything in two weeks. The next day, when Clements came into the lab, he couldn’t find the sun star. There was a pile of urchins on the side of the tank, with something red barely visible underneath. Clements pried the urchins off, revealing the victim. “The sea star was absolutely decimated,” he says. “The urchins had just ripped it apart.” Clements and his colleagues soon realized this behavior hadn’t been documented before, So, the team ran two trials, each with a single sun star in the urchin tank, recording how this “predator-prey role reversal” plays out. One urchin would approach the sun star, feeling around, eventually attaching to one of the sun star’s many arms. Other urchins would follow suit, covering the sun star’s arms. When the team removed the urchins after about an hour, they found the arm tips were chewed off, along with the eyes and other sensory organs positioned there.
5-21-21 Some bird embryos know to hide from predators even inside their eggs
The world is a dangerous place for young birds, but it seems that even as embryos, some can take measures to hide from hungry predators. Late in their embryonic development, many bird species will communicate with their parents through the eggshell by chirping. Kristal Kostoglou at Deakin University in Melbourne, Australia, wanted to know if these talkative embryos already have the predator-avoiding instincts of hatched chicks, which hide and fall silent when threatened. Kostoglou and her colleagues exposed the eggs of two Australian shorebird species – 56 red-capped plover (Charadrius ruficapillus) eggs and 299 masked lapwings (Vanellus miles) eggs – to different signals of a predator approaching, like predator calls, parental alarm calls, increased parent heart rate sounds or changes in light level from a parent bird moving off the nest. The team then recorded how often the embryos called under these conditions. The researchers didn’t find any effects from a change in light or heart rate, but the embryos of lapwings went from calling just over once per minute under white noise, to once over three minutes when exposed to the sounds of egg-eating little ravens (Corvus mellori), suggesting they were hushing up to avoid predators. The plovers’ call rate was about four times per minute under white noise, but dropped to twice per minute with the predator noises. Jose Noguera at the University of Vigo in Spain says these findings and earlier research on prenatal birds “clearly show that embryos are not passive agents to external cues”. Noguera says he is surprised that the embryos didn’t also call less in response to parental alarm calls. “Alarm calls may serve as a more reliable cue of predator presence, as some predators can be very silent,” he says.
5-21-21 Big cats seized from park belonging to Tiger King couple
Federal officials have seized 68 big cats from Jeff and Lauren Lowe, stars of the hit Netflix show Tiger King. On Thursday, the US Justice Department announced they had confiscated the exotic animals from the couple's Tiger King Park in Oklahoma. Officials have inspected the zoo three times since December 2020 and have issued multiple citations for failure to properly care for the animals. Seven lions, 46 tigers, 15 lion-tiger hybrids, and one jaguar were recovered. The Lowes are both accused of violating US laws on endangered species and animal welfare. During government inspections, they were repeatedly cited "for failing to provide the animals with adequate or timely veterinary care, appropriate nutrition, and shelter that protects them from inclement weather and is of sufficient size to allow them to engage in normal behaviour", according to a news release from the Justice Department. The couple were found to be in contempt after failing to follow court orders to hire a qualified veterinarian to ensure that the cats could receive levels of care required under the Animal Welfare Act. Many of the animals were found to have bone disorders due to calcium deficiency from eating boneless and ground meat, officials say. In a federal affidavit, officials said the Lowes harassed government workers during inspections, with Mrs Lowe at one point threatening to kill a wildlife official. "The statement was especially intimidating because their former Tiger King business partner is serving a prison sentence for hiring a hit man to assassinate a business rival in another state," the charging document states. Mr Lowe is the former business partner of Joe Exotic, star of the hit show. Exotic, real name Joseph Maldonado-Passage, is currently serving a 22-year sentence for his involvement in a contract killing plot and animal abuse.
5-20-21 Common swifts can fly more than 800 kilometres a day during migration
Small birds like swifts and swallows that migrate long distances have been predicted to travel up to 500 kilometres per day, but new evidence shows that one species of swift can cover far more ground than that. Small birds like swifts and swallows that migrate long distances have been predicted to travel up to 500 kilometres per day, but new evidence shows that one species of swift can cover far more ground than that. Susanne Åkesson and Giuseppe Bianco at Lund University in Sweden have shown that common swifts (Apus apus) can fly an average of 570 kilometres per day. The fastest swifts covered 832 kilometres a day. Swifts can fuel up on insects without landing, which allows them to remain in flight for about 10 months of the year. “They are very special birds. Thanks to their small size and also this fly-and-forage strategy, they can generate very high migration speeds over time,” says Åkesson. “For ordinary birds, like waders and ducks and songbirds, they need to be spending some time sitting on the ground foraging before they fly, but the swifts, they can feed a little bit every day and feed on the wing.” Åkesson and Bianco used geolocators to track the migration patterns of common swifts that breed in Sweden’s northern province of Lapland and migrate to areas south of the Sahara desert. The swifts leave Lapland each year around mid-August and return north at the end of May. The pair tracked 19 swifts in the autumn, when the migration included 20 flying days and 22 stopover days on average, and 20 swifts in the spring, which involved 15 travel days with five stopover days, on average. In the spring, “they have a chance to find very good tailwind conditions, especially at high altitudes”, says Åkesson. The ease of finding insects in the spring may also make it a shorter migration than the autumn trip. The pair’s analysis of weather along the migration route showed that the birds seemed to time their departure by anticipating future wind conditions. Åkesson says it’s not clear how the swifts do this, but previous studies have shown that birds are sensitive to air pressure changes.
5-19-21 Cicadas set to emerge in once in every 17-year event
This intricate image of a cicada shedding its skin in the US state of Maryland was taken by Carolyn Kaster. Trillions more will soon emerge across the country for a brooding event that occurs once every 17 years. THIS remarkable image shows just one of the trillions of cicadas starting to emerge in 15 US states after 17 years underground. Carolyn Kaster’s photo captures an adult insect shedding its old skin on the bark of an oak tree in Maryland, before it goes in search of a mate. More than 3000 cicada species have been described worldwide. Most have a yearly life cycle, but seven species in the US belonging to the Magicicada genus remain underground as nymphs for 13 or 17 years before emerging, a process called periodical brooding. The only other two species of cicada to do this are found in Fiji and India. This year, insects from a group called Brood X – which is made up of three species – will emerge in the eastern US in their trillions. It is one of 15 broods in the country, and last appeared in 2004 (see photo above). Cicadas from Brood X have already been spotted in Georgia, Maryland and Virginia. After mating, females lay their eggs in the stems of woody plants. Remaining underground for so long may make it harder for predators to remember where to find the insects, giving the next generation a survival advantage when they eventually emerge.
5-19-21 Spiders avoid surfaces that have previously been covered with ants
House-dwelling spiders avoid surfaces that certain aggressive ants have walked over, suggesting that there may be some sort of chemical the ants leave in their wake that could form the basis of an ecologically sound way to keep spiders out of people’s houses. Alongside his regular spider sex pheromone research, Andreas Fischer at Simon Fraser University in Vancouver, Canada, has been seeking practical ways to maintain healthy ecosystems while keeping arachnophobic humans comfortable in their own homes. He says commercial pesticides “kill everything”, disrupting ecosystem balances. Meanwhile, Fischer’s previous testing revealed that popular “natural” spider repellants like lemon zest and mint oil have little to no effect on spiders. Recently, Fischer realised other scientists were noting that where they found more ants, they found fewer spiders. Wondering if ants naturally repelled spiders through chemical traces, Fischer and his colleagues gathered workers from three different species of ant and females from four species of common North American house spider from their university campus and nearby areas. In each experiment they let ants of a particular species run around on filter paper in one part of a glass cage for 12 hours. To keep the experiment fair, the scientists weighed the ants – which varied significantly in body size – and used an equivalent mass of ants of a given species in each experiment. This meant one ant species was represented by 43 ants but another by just 3 ants. Then they removed the ants and put young female spiders, one at a time, into the cage and watched to see where they chose to settle after 24 hours. Most of the black widows (Latrodectus hesperus), false widows (Steatoda grossa) and hobo spiders (Eratigena agrestis) avoided the filter paper previously traversed by European fire ants (Myrmica rubra), says Fischer. A fourth species, the cross spider (Araneus diadematus), showed a similar trend, but it wasn’t as strong.
5-19-21 European fire ant chemicals may send spiders scurrying away
But don’t go adding the invasive, biting insects to your home as an arachnid repellent. To make a spider flee, bring on the fire ants. Or rather, just their chemical signals. Some spiders common in North American homes avoid building their webs in chambers that recently housed European fire ants, researchers report May 19 in Royal Society Open Science. The ants probably left behind chemical traces, the researchers say. That could signal danger to the arachnids because ants sometimes feast on spiders. The reaction hints that the insects might be a source of natural spider-repelling chemicals. “A lot of people are afraid of spiders, and there’s nothing on the market that is reliable that keeps the spiders away,” says Andreas Fischer, an arachnologist at Simon Fraser University in Burnaby, Canada. Fischer and his colleagues housed false black widow spiders (Steatoda grossa) in a glass container with three connected chambers. The arachnids were less likely to settle down in empty compartments that had once contained European fire ants (Myrmica rubra), an invasive species in North America. Other spider species — black widow (Latrodectus hesperus), cross (Araneus diadematus) and hobo (Eratigena agrestis) — also had an aversion to the former fire ant chambers. The finding is exciting but not ready for real-world use, Fischer says. “I really hope that people don’t go out there and get European fire ants into their garden to get rid of spiders.” The ants are aggressive, “horrendous pests” with stinging bites and are tough to get rid of. Another type of fire ant (Solenopsis invicta) native to South America is among the costliest invasive species in the world (SN: 3/31/21). The team plans to pinpoint what chemical spooks the spiders and figure out if it can be made in the lab. Then the researchers will make sure the potential spider repellent is not toxic or a homing beacon for ants.
5-18-21 Science with Sam: Why do cats go crazy for catnip?
Catnip turns fearsome felines into drooling balls of fluff. But how? This week, Science with Sam explains why cats love catnip. If your cat turns from an elegant hunter into a drooling ball of fluff at the merest whiff of catnip then you might be curious to know how such a nondescript plant has the power to cripple such a ferocious beast. Seventy per cent of domestic cats are susceptible to catnip, and so are big cats such as lions, but how did this plant evolve to hold such sway over our pets, and what exactly is it doing to them? This week, Science with Sam explains why cats love catnip. Cats are fearsome predators. Fast, stealthy, ruthless. Why aren’t you stalking your prey like an assassin? Stay focused! Oh no. This cat is broken. What’s done this to you? A herb?! Why does this nondescript plant drive this ferocious carnivore crazy? Are you high? I need some answers. Catnip comes from the plant Nepeta cataria, a herbaceous member of the mint family native to Europe and Asia. When cats get a whiff of it, they seem compelled to sniff, lick and chew its flowers and leaves, rub their faces and bodies on the plant, roll around, shake their heads and drool. Not all cats are affected, though. Kittens are immune to its allure and thanks to a genetic variation, 7 out of 10 adult cats find it irresistible, but the rest aren’t really bothered. The chemical responsible for messing with cats’ heads is called nepetalactone. It produces its effect through smell alone: the molecule doesn’t have to be ingested or reach the brain for it to send cats wild. This frenzy of excitement usually lasts around 15 minutes. After that, they become immune to its effects for around an hour. It might look like the cats are getting stoned, or having some kind of drug trip. We can’t actually tell what the cats are experiencing, but we do know that smelling catnip triggers the release of beta-endorphins, natural opioid chemicals produced in the body.
5-18-21 Female mice that lose a male partner are wary of taking a new one
Female mice who mate for life seem to take longer to get over the loss of their partner than male mice. The females are slower to begin a sexual relationship with a new partner – perhaps because life experience has taught them to be sceptical that a new male will stick around and help care for pups. California mice (Peromyscus californicus) are monogamous rodents that form lifelong relationships with a partner, sharing a home and parenting duties. But if the partner dies or disappears, the bereaved mouse often finds a new life partner and reproduces. Amber Valentino at Saint Joseph’s University in Pennsylvania and her colleagues discovered that this process happens more quickly if the bereaved mouse is male. A bereaved female might be “choosier” and so take longer to find a new partner, says Valentino. The scientists speculate that this may be because the loss of a first mate leaves a female questioning the reliability of a new one. “They need that extra paternal component, a male who will be there and who will actively engage in the successful rearing of offspring,” says Valentino. “So we suspect their decision to go ahead and have pups with another male takes longer based on the previous experiences they have faced.” Valentino and her colleagues examined the birth records of 59 California mice couples in their laboratories in which one was a virgin and the other had lost a partner within the preceding 24 hours (usually because the partner mouse had died of natural causes). The team found that approximately 85 per cent of these mice couples had a litter of pups. This is about the same success rate as the researchers reported from a connected experiment involving 525 virgin-virgin mouse couples, says Valentino. However, the pups typically came sooner when it was the male getting a new partner, she says. In fact, bereaved males entered a sexual relationship with a virgin female just as fast as they did with their first partner, with pups being born on average 55 days after the first meeting.
5-18-21 More than a billion sparrows in the world, study finds
There are at least 50 billion individual wild birds in the world, according to a new estimate. House sparrows alone make up about 1.6 billion of these. And three other species - European starlings, barn swallows and ring-billed gulls - also have populations exceeding one billion birds. However, most bird species are rare, with about one-in-ten species down to fewer than 5,000 individuals, say the authors. This "snapshot" of the global bird population will help in conservation efforts to save birds from extinction, says a team at the University of New South Wales in Sydney, Australia. "We spend a lot of time and money counting our own species, but we really need to think about how we count the biodiversity that we share the planet with," study researcher Dr Corey Callaghan told BBC News. Counting the number of birds in the world is a complex task, with no definitive answers. Past rough estimates have come up with 200 to 400 billion individual birds drawn from 10,000 to 13,000 bird species. The Australian researchers analysed 9,700 species of living birds (excluding all domestic birds) using data recorded by birdwatchers on the online database, ebird, over the past decade. They refined the data using modelling and information from experts on the ground to come up with what they say is a more accurate estimate. The study, published in the Proceedings of the National Academy of Sciences, suggests most birds are found in the northern hemisphere: in Europe, northern Asia, northern Africa, parts of the Arabian Peninsula, and North America. In contrast, very few birds are found in Madagascar and the Antarctic. "The citizen science data will play a fundamental role in the future in biodiversity monitoring," said Dr Callaghan.
5-17-21 There are 50 billion wild birds on Earth – but four species dominate
Earth is home to around 50 billion wild birds according to a new global estimate, but most species are very rare and only a handful number in the billions. Just four undomesticated species are in the club of those with a billion-plus individuals, with house sparrows (Passer domesticus) the most abundant, followed by European starlings (Sturnus vulgaris), ring-billed gulls (Larus delawarensis) and barn swallows (Hirundo rustica). By contrast, 1180 species number fewer than 5000 birds each. “One of the takeaways is mother nature just loves rare species. It’s what some refer to as hyper dominance, which has been found in Amazonia tree flora and other plant groups. It’s not terribly surprising, but it’s good to have the data,” says Corey Callaghan at the University of New South Wales, Australia, who led the research. The estimate of around six wild birds for every human on the planet is the first since researchers arrived at a global figure of 200 to 400 billion undomesticated birds 24 years ago. The big gap between the studies isn’t due to a dramatic decline in bird numbers, but is explained by a more sophisticated method that used data for more species. Callaghan and his colleagues took citizen science data on bird sightings from the online database eBird to build a model that estimated global numbers for species. To ensure it was working well, they cross-checked the results for 724 species with other rigorous data sources on well-studied birds. The model was then extrapolated out to 9700 species, arriving at a median of 50 billion wild birds globally. The citizen science sightings underpinning the research are both its strength and weakness, says Richard Gregory at UK charity the Royal Society for the Protection of Birds. eBird has far less data on birds in the tropics than in temperature regions, he says. For instance, the red-billed quelea is sometimes regarded as the most numerous undomesticated bird on the planet, but in the new analysis its population is estimated at just 95 million.
5-17-21 Hermit crabs choose by colour when selecting a new shell for a home
Hermit crabs prefer to occupy darker-coloured seashells, especially if they are living in a dark and gloomy environment. These tiny crabs often swap shells as they try to find their ideal home. Research has previously shown that hermit crabs on the hunt for a new shell consider its size, condition and shape – features that vary depending on the species of animal to which the shell originally belonged. To see if colour is also on their list, James Rimmer at the University of St Andrews, UK, and his colleagues painted empty common periwinkle (Littorina littorea) shells either solid black or solid white. Then they collected wild, adult common hermit crabs (Pagurus bernhardus) from the coast of Fife in Scotland. In their first experiment, the researchers removed 67 crabs from their current shells and put each one in a well-lit tank with two black and two white shells. Then they repeated the experiment with another 60 naked crabs, this time with the tank in total darkness. In the light, two thirds of the crabs grabbed the darker shells, says Rimmer. But in the dark, when the crabs couldn’t see the colours, they selected randomly, with a 50/50 split between the black and white shells. Encouraged by these results, the researchers placed 96 naked crabs – 12 at a time – in a larger, well-lit tank with either a black or a white background, along with 20 black and 20 white shells. The crabs had 24 hours to pick and choose. Then the experiment was run again with another 96 crabs, using red and yellow shells and backgrounds instead. With ample time to try out different shells and reconsider their choices, at the end of the day, the 192 crabs showed an overall preference for the darker-coloured shells (those that were either black or red), says Rimmer. This was particularly true when the background was black or red, with only around 25 per cent of crabs opting for a light-coloured shell.
5-17-21 On the hunt for platypus DNA in Australia's waterways
“Platypus and fish are all shedding DNA into the water – it can be skin cells, hair cells, scales,” says ecologist Josh Griffiths. “A lot of it is actually urine and faeces – which, next time you’re swimming in the river, is probably not a great picture.” There are a few chuckles from the dozen or so members of the Moorabool Catchment Landcare Group, who have joined Griffiths at a park in Ballan, a town in Victoria, Australia, located 78 kilometres north-west of Melbourne. Griffiths works for EnviroDNA, a company that detects DNA from environmental samples in order to monitor populations of animals in particular locations. In partnership with Odonata, a biodiversity non-profit, the team is hoping to map the whereabouts of platypuses in Victorian waterways. Group members have volunteered their Saturday morning to join the search. Expecting dreary weather, everyone is dressed accordingly – rain jackets and wellies abound – but it turns out to be a brilliant autumn morning. In the trees surrounding us, crows caw as Griffiths explains the programme for the day and gives a short safety briefing. “Look out for snakes and stings— so typical outdoor issues,” he says, and because we are all Australian, nobody bats an eyelid. Our job today is to take samples from the Moorabool river, which is flowing at around 10 per cent of its usual volume. There are 18 sampling sites in total. People are assigned three or four sites each and given printed satellite maps with marked locations as well as testing kits in bright blue fabric lunchboxes. Though most of us are wearing waterproof shoes, we are told not to get into the water if possible. This is partly to avoid disturbing sediment in the water, which can clog up the fine sampling filter, and partly to avoid contaminating the water with anything that may be on our boots, like dog faeces.
5-17-21 Australia crocodile: Skull identified as part of new extinct species
An eight-million-year-old crocodile skull discovered in central Australia is now believed to be part of an extinct species new to scientists. The skull had been found about 200km (125 miles) from Alice Springs, in the Northern Territory (NT), in 2009. It was thought to belong to a known reptile of the Baru genus but that has now been updated with new study. The species is expected to be named in 2022, and there is a Baru exhibition in the NT. Dr Adam Yates, senior curator of Earth Sciences at the Museum and Art Gallery of the Northern Territory, said the skull was found at the Alcoota fossil site in central Australia. Dr Yates told the BBC the skull was by far the best specimen of a Baru crocodile yet found. "It tells us about a new species that we didn't realise was inhabiting central Australia. It's somewhat surprising to imagine that central Australia had rivers to support crocodiles," he said. "It's one more thread in the tapestry in understanding the way Australian fauna has evolved over time." Dr Yates said that while it was known that the Baru genus roamed this part of the country many millions of years ago, the ancient skull discovered at Alcoota was from "an undescribed species of crocodile. It belongs to a species that has not yet been given a scientific name, it is distinctly different from its closest relatives". He said crocodiles today are from a "completely different branch of the crocodile family tree". The new, extinct species had a number of anatomical differences from other crocodiles. "It is the most heavily robust member of the genus Baru. It has particularly large teeth… so it has a lower number of teeth," Dr Yates said. "This was a crocodile that was attacking big prey. Big megafauna." The Baru is part of an exhibit at the Museum and Art Gallery of the Northern Territory and the new species was first reported by ABC News. The 2009 skull is not part of the exhibit but there is a reconstructed, 3D-printed skeleton of the crocodile on display.
5-16-21 The mid-air walkways saving endangered animals
Conservationists have come up with an ingenious way to help an endangered species – the Javan slow loris. They've built a network of mid-air walkways to help them move between treetops, across land that has been cleared for growing crops. And the farmers who own the land are keen to co-operate because the walkways have another special feature that makes their lives easier too.
5-16-21 The essential fly
When entomologist Jonathan Finch turns his dust-caked car off the highway and onto the old wartime airstrip at Manbulloo, he knows what awaits him at the other end: 65,000 blooming mango trees, an indescribably horrible smell, and the unmistakable buzz of excited blowflies. These days, the old airstrip is the access road to the vast Manbulloo mango farm — 4 square kilometers of orchards near the town of Katherine in Australia's Northern Territory. "It's a beautiful place — remote, peaceful and blissfully shady beneath the trees," Finch says. "But the smell is unbelievable. You just can't get it off you." Although we are talking on the phone, I get the impression he's grinning. The loathsome odor, it turns out, is one he created himself. And it's vital to his research into the pollinating prowess of flies. Most of us don't much like flies. Finch, though, is a big fan. He's part of a team investigating the role that flies play in pollinating crops and whether, like honeybees, they might be managed to improve yields. He's traveled from Western Sydney University on the other side of the continent to test a widely held belief among mango growers: If you leave out rotting carcasses, flies will come, and more flies mean more mangoes. Mango growers realized way back that flies are important pollinators. "Some encourage flies by hanging large barrels from their trees and putting roadkill in them," Finch says. "Other guys bring in a ton of fish and dump it in a heap in the middle of the orchard." The farmers are convinced that the pungent bait makes a difference, and the biology of blowflies suggests that it might. Yet there's no scientific proof that it does. Blowflies are drawn to the smell of rotting flesh because they mate and lay their eggs on corpses and carcasses. They also forage among flowers to fill up on energy-boosting nectar and protein-rich pollen, transporting pollen from one flower to another in the process. So it seems fair to assume that extra flies will pollinate more flowers and the trees will bear more fruit. But do they? To find out, Finch and his colleagues have coopted the Manbulloo farmers' bait barrels and filled them with a mix of fish and chicken. With the temperature hovering around 30ºC (85ºF), the scent of decay soon wafts through the trees and the team can put the idea to the test. Flies generally get a bad rap. People associate them with dirt, disease and death. "No one except entomologists really likes flies," Finch says. Yet there's good reason why we should cherish, encourage, even nurture them: Our future food supply could depend on it. The past few years have seen growing recognition that flies make up a large proportion of wild pollinators — but also that we know little about that side of their lives. Which sorts of fly pollinate what? How effective are they at delivering pollen where it's needed? Which flies might we harness to boost future harvests — and how to go about it? With insect populations plummeting and honeybees under pressure from multiple threats, including varroa mites and colony collapse disorder, entomologists and pollination specialists are urgently trying to get some answers. Animals are responsible for pollinating around 76 percent of crop plants, including a large number of globally important ones. Birds, bats, and other small mammals do their bit, but insects do much more — pollinating flowers of many fruits, vegetables, and nuts, from almonds to avocados, mangoes and melons, cocoa and coconuts, as well as crops grown to provide seed for future vegetable harvests. In a recent analysis for the Annual Review of Entomology, Australia-based biologist Romina Rader and colleagues from Australia, New Zealand, and the U.S. calculated that the world's 105 most widely planted food crops that benefit from insect pollination are worth some $800 billion a year.
5-15-21 The U.S.’s first open-air genetically modified mosquitoes have taken flight
After long debate, Oxitec pits a GM mosquito against a Florida invasive species spreading Zika and dengue. The first genetically modified mosquitoes that will be allowed to fly free outdoors in the United States have started reaching the age for mating in the Florida Keys. In a test of the biotech company Oxitec’s GM male mosquitoes for pest control, these Aedes aegypti started growing from tiny eggs set out in toaster-sized, hexagonal boxes on suburban private properties in late April. On May 12, experiment monitors confirmed that males had matured enough to start flying off on their own to court American female mosquitoes. This short-term Florida experiment marks the first outdoor test in the United States of a strain of GM male mosquitoes as a highly targeted pest control strategy. This strain is engineered to shrink local populations of Ae. aegypti, a mosquito species that spreads dengue and Zika (SN: 7/29/16). That could start happening now that the GM mosquitoes have reached mating age because their genetics makes them such terrible choices as dads. The mosquitoes now waving distinctively masculine (extra fluffy) antennae in Florida carry genetic add-ons that block development in females. No female larvae should survive to adulthood in the wild, says molecular biologist Nathan Rose, Oxitec’s chief of regulatory affairs. Half the released males’ sons, however, will carry dad’s daughter-killing trait. The sons of the bad dads can go on to trick a new generation of females into unwise mating decisions and doomed daughters (SN: 1/8/09). The trait is not designed to last in an area’s mosquitoes, though. The genetics just follow the same old rules of natural inheritance that mosquitoes and people follow: Traits pass to some offspring and not others. Only half a bad dad’s sons will carry the daughter-killing trait. The others will sire normal mosquito families.
5-15-21 Cranes: Flying giant returning to Ireland after 300 years
A giant bird that has been part of Irish folklore and was often kept as a pet in medieval times could be returning to the island after an absence of more than 300 years. A pair of cranes are nesting on a rewetted peat bog in the Republic of Ireland's midlands. It is hoped they could be the first of the species to breed in Ireland for centuries. The cranes are on land owned by former peat producer Bord na Móna. The location is to remain confidential to protect the birds. In January, Bord na Móna ceased peat harvesting for good and has been rehabilitating thousands of hectares of boglands, rewetting the drained sites. The company's lead ecologist, Mark McCorry, said the return of the nesting pair of cranes was very significant. "While we have these birds coming to Ireland during the winter, we generally haven't seen them in the breeding season," he said. "So last year, when they were discovered, they were the first pair that were in a nest during the breeding season. "So it's really a great indication that they look like they're ready to re-colonise Ireland again. "It's a very iconic species in Ireland, it's very associated with folklore as well - there's lots of stories around it." Mr McCorry said he was "reasonably optimistic" that the birds would successfully breed. "They failed last year, but they did produce eggs. Obviously we didn't confirm any young, but that's not uncommon for cranes," he said. "Generally these birds, when they pair up and they're young, it takes them a few years, or a few goes, before they become successful breeders." However, Mr McCorry said there is also the possibility that the species has already begun to re-establish itself in Ireland, as a juvenile crane was spotted at an estuary in County Dublin last autumn. "It would be suspected that if it was a juvenile crane, it bred somewhere in Ireland," Mr McCorry said. "So it's not beyond the bounds of possibility that this pair of cranes are not the only pair now in Ireland.
5-14-21 Elephants are dying in droves in Botswana. Scientists don’t know why
Thirty-nine elephants have died as neighboring Zimbabwe nails a fresh killer pathogen. Die-offs of African elephants have once again erupted in Botswana. In just the first three months of 2021, 39 have succumbed. The mysterious deaths occurred in the Moremi Game Reserve, in the northern part of the country, nearly 100 kilometers from a region of the Okavango Delta, where about 350 African elephants died during May and June in 2020. Puzzled scientists have been calling for thorough investigations as the government sends mixed messages on the cause of death. Anthrax and bacterial infections had been ruled out in the new deaths and “further laboratory analysis is ongoing,” Botswana’s Department of Wildlife and National Parks reported in a March 24 news release. However, the 39 recent deaths were linked, based on preliminary results, to the same cyanobacteria toxins blamed for last year’s mass die-off, said Philda Kereng, Botswana’s Minister of Environment, Natural Resources Conservation and Tourism, in a March 30 state television address. Remote sensing of areas of last year’s mass die-off supports the cyanobacteria theory. From March through July 2020, cyanobacteria abundance increased continuously as water sources were shrinking, researchers report online May 28 in the Innovation. With climate change, bodies of water get warmer and toxic cyanobacteria thrive. Other evidence points to a pathogen as well. “The 2021 elephant mortalities are again specific to elephants, as was the case in 2020,” says Shahan Azeem, a veterinary scientist at the University of Veterinary and Animal Sciences in Lahore, Pakistan. If anthrax were to blame, other animals would have been affected, but they were not. And there would have been the telltale signs of bleeding on the carcasses, which was not the case. Poaching was also ruled out, because the elephants’ bodies were intact with their tusks. An investigation of the larger 2020 die-off suggests that a pathogen may have been the cause, Azeem and colleagues reported online August 5, 2020, in the African Journal of Wildlife Research.
5-14-21 Native oysters reintroduced into Firth of Clyde
Oysters have been reintroduced to the Firth of Clyde as part of a restoration project to bring them back from the brink of extinction. Some 1,300 native oysters have been suspended below pontoons in Largs Yacht Haven and Fairlie Quay Marina. The native oyster (Ostrea edulis) is a marine bivalve mollusc found in Scotland mainly on the west and north coasts. Populations have declined 95% since the 1800s. The oysters have been impacted by pollution, climate change and shellfish harvesting. This means the benefits that the native oyster provides to the ocean - including each oyster filtering 200 litres of water each day and acting as an important habitat for marine wildlife - have been lost. Scientists hope they will reproduce in the Firth of Clyde and lead to millions of larvae being released into the sea in the months ahead. The 1,300 oysters are housed in nurseries, which create a micro-habitat where they can reproduce - much like a maternity ward to the next generation of oysters. A total of 4,000 native oysters have been placed in the waters around Great Britain as part of the three-year Wild Oysters Project. The others have been deployed into nurseries underneath marina pontoons in Tyne and Wear in England and in Conwy Bay in Wales. The project is a partnership between the Zoological Society of London, Blue Marine Foundation (BLUE) and British Marine, with £1.8m funding from the Postcode Dream Trust. Celine Gamble, of the Zoological Society of London, said there was "just a handful" of known oyster populations left across the 4000 sq km sea area of the Clyde. She told Radio Scotland: "Oysters are known as little superheroes of the sea. "Although they're small in size, they're capable of making some huge changes in our marine environment." Ms Gamble said the project would restore oyster reefs, and provide an "abundant and healthy eco system that can support other marine wildlife".
5-13-21 Deep-sea snailfish repairs its DNA to survive 7 km below the surface
With pressure pushing down on it, a deep-sea fish has evolved a catalogue of adaptations to help it survive in the crushing depths of the Pacific Ocean. The fish has extra genes for repairing its DNA and for making a chemical that stabilises essential proteins. It has also lost many of the genes that underpin the sense of smell, perhaps because it has a limited diet. The fish was collected in 2017, when the Chinese submersible Jiaolong descended into the Yap Trench in the western Pacific Ocean. At a depth of 6903 metres, the submersible caught two fish belonging to a previously unknown species. They were snailfish, a little-studied group of fish whose members live at a huge range of depths. Snailfish look a bit like tadpoles, and don’t have scales: their bodies are jelly-like. Because the new species was found in the hadal zone, which begins at 6000 metres below sea level, it has been tentatively called Yap hadal snailfish. At such depths, there is no sunlight, the water is cold, food is scarce and the pressure is intense. To find out how the Yap hadal snailfish survives, researchers led by Xinhua Chen at Fujian Agriculture and Forestry University in Fuzhou, China, have now sequenced its genome. They found that the snailfish genome has extra copies of genes involved in DNA repair, including eight copies of a gene called rad51. Some DNA repair genes also contained mutations that would alter the proteins they coded for – although it is unclear at the moment if or how this is a helpful adaptation for life at depth. The snailfish also had five copies of a gene called fmo3, which is crucial for the production of trimethylamine N-oxide (TMAO): a chemical that stabilises proteins and may protect them from becoming damaged by the intense pressure. In line with this, the snailfish’s muscle tissue had elevated levels of TMAO, compared with zebrafish that live in shallower waters.
5-13-21 'Cocaine of the sea' threatens critically endangered vaquita
The vaquita marina is found only in Mexico. It is the most critically endangered sea mammal on the planet, its survival threatened by a deadly clash of interests between fishing and conservation. Scientists estimate there may be fewer than a dozen left in the wild. Jacques Cousteau, the marine explorer, called the Sea of Cortéz, also known as the Gulf of California, "the world's aquarium". One of its treasures is a silvery-coloured porpoise with wide, panda eyes. But the vaquita's days may be numbered because of illegal fishing for another protected species: totoaba. Totoaba, a fish that can grow as large as a vaquita, was a food source before it was placed on Mexico's endangered list. "We used to catch it in the 60s and 70s," remembers Ramón Franco Díaz, president of a fishing federation in the coastal town of San Felipe, on the peninsula of Baja California. "Then the Chinese came with their suitcases full of dollars, and bought our consciences." They arrived wanting the totoaba's swim bladder, an organ that helps the fish stay buoyant. In China it is highly prized for its perceived - though unproven - medicinal properties. According to the Earth League International NGO, 10-year-old dried swim bladders can sell for $85,000 (£60,000) a kilo in China. The fishermen of San Felipe make only a tiny fraction but in a poor community, business has boomed for the "cocaine of the sea". "The illegal fishermen - the criminal elements - are so strong that in the plain light of day you see them with their illegal nets and totoaba," says Mr Franco Díaz. Every afternoon during the season, a stream of pick-up trucks towing fishing boats reverses down the concrete slipway of the town's public beach and into the sea. These craft are mostly unlicensed, and their crew use nets that can kill the vaquita. "Gillnets might be hundreds of metres long and 10 metres high," says Valeria Towns, who works with a Mexican NGO, Museo de la Ballena. "They become a wall under water."
5-12-21 'Whale sharks gulp down air to float vertically while feeding
Whale sharks are the world’s largest living fish, measuring up to 18 metres long, but somehow they can suspend themselves in an upright position despite having a body density that is greater than that of seawater. A study of captive whale sharks suggests this may be due to air they take in as they feed at the water’s surface. Scientists have previously observed whale sharks (Rhincodon typus) feeding vertically in the wild. Although they often use slow fin movements to hold themselves in place while feeding on plankton at the surface, the sharks occasionally remain completely still without sinking or tipping sideways, says Taketeru Tomita at the Okinawa Churashima Foundation Research Center in Japan. He and his team found that the whale sharks in their aquarium didn’t have to move all the time to stay upright. Fascinated, they then realised that the animals would suck in air from the surface while taking in prey. When they stopped sucking in air, they would sink. To understand how the air helps them float, the researchers calculated estimates for body volume, mass and density for two sharks. They then equipped one shark with underwater ultrasound equipment, which detected air in its gill cavities when it was feeding vertically, but not at other times. Using this data, they created a mathematical model to determine how much air the whale shark would need to stay vertically afloat and immobile, based on its dimensions. Their calculations revealed that, in theory, around 0.2 cubic metres of air would provide the necessary buoyancy for each of their study sharks, says Tomita. Considering the size of the sharks’ mouths, the researchers say the animals could easily suck in that much air each time they reach the surface. Becoming buoyant might not be the main reason why whale sharks suck in air – although it could be a useful side effect, says Tomita. “We suspect that water suctioning at the surface is an efficient way to gather food floating on the surface layer of the water, but we do not completely understand this mechanism.”
5-12-21 Cats must be microchipped under animal care plan
Microchipping pet cats will become compulsory under a wide-ranging new animal welfare plan. Environment Secretary George Eustice told the BBC the policy would be monitored by vets and enforced in the same way as it is for dogs, which he said has led to over 90% compliance. The plan will also formally recognise the sentience of many animals. But Mr Eustice said this measure was aimed at pets and livestock, rather than wild animals. The government's Action Plan for Animal Welfare also includes measures to ban exporting live animals for slaughter, the keeping of primates as pets and importing hunting trophies. There may also be changes to the ways that animals can be confined - such as the practice of keeping them in cages. However, there is no plan to require imports to meet the same welfare standards as in the UK, which the National Farmers' Union (NFU) described as "hypocrisy". The plan will also see remote-controlled training collars for dogs outlawed and the government says it will look at banning the sale of foie gras - a food made from the livers of force-fed ducks or geese. Speaking on BBC Breakfast, Mr Eustice said that compulsory microchipping for cats would resemble the current rules for dogs, where vets advise pet owners whose animals do not have a microchip to get one, and "if they ignore it, there is an enforcement process". Dog owners can be fined £500 under the existing law. Lianna Angliss at Hopefield Animal Sanctuary said that as well as helping to reunite lost cats with their owners, compulsory microchipping could help animal sanctuaries trace people who abandon their pets. The environment secretary also told BBC Radio 4's Today programme that the recognition of animal sentience would give the UK an equivalent to a declaration that already applies in the European Union.
5-11-21 Rare video of giant squid reveals it stalks jellyfish in deep water
In the first footage of its kind, researchers have filmed a giant squid stalking an electronic decoy jellyfish (E-Jelly) before striking it with lightning-quick speed. “It comes right in, shoots its arms out [and] wraps its arms around the E-Jelly,” says Nathan Robinson at the Oceanographic Foundation in Valencia, Spain. Giant squid (Architeuthis dux) patrol the waters in search of prey, such as jellyfish, deep in the so-called twilight zone, and they are famously elusive. The E-Jelly is part of an elaborate device designed specifically to capture footage of them. These squid have eyes the size of dinner plates, says Robinson, and they are very sensitive to the lights that humans typically use when descending into deep water. But Robinson’s colleague Edith Widder at the Ocean Research & Conservation Association in Florida and her team developed a device that uses red light, which the squid can’t see as well, to illuminate the field in the camera. The E-Jelly looks like a drink coaster with coloured lights around the edge that mimic those of bioluminescent jellyfish that the squid can see. It acts as bait for squid that prey on these jellies, sitting right in front of a camera. The team took the set-up to waters about 160 kilometres south of Mobile, Alabama, capturing the first known footage of giant squid in the Gulf of Mexico, in June 2019. Giant squid can be up to 40 metres long, though this individual was only about 6 metres long including its tentacles and arms. Previously, researchers believed these giants hunted by ambush to conserve energy in the relatively barren depths of the twilight zone between 400 metres and 1000 metres in depth. But this video shows the squid actively stalking and striking at its presumed prey, the E-Jelly. The discovery suggests that giant squid survive deep under the surface by being efficient hunters rather than waiting in ambush for opportunities to pass them.
5-11-21 Houston suspect arrested as pet tiger remains on the loose
A murder suspect in Texas who was out on bail has been taken back into custody after neighbours called the police to alert them to a pet tiger wandering around a Houston neighbourhood. When officers arrived on Sunday, the man put the Bengal tiger in an SUV, and drove off, police said. Victor Hugo Cuevas, 26, now faces a separate charge of evading arrest, police said. The tiger is still on the loose. Footage shared on social media appeared to show a tiger on the leafy suburban streets. Houston Police confirmed that Mr Cuevas had been arrested for evading arrest - but added that they did not know where the tiger was. Police Commander Ron Borza told reporters on Monday that the main concern had been finding both Mr Cuevas and the animal: "We have plenty of places we can take that tiger and keep it safe, and give it a home for the rest of its life. "A lot of time, people get desperate and do silly things. We want to get him and get the tiger to a safe place." Mr Cuevas' lawyer, Michael Elliott, said his client was not the owner of the tiger or taking care of the animal. He said his client was not guilty of any crime. Tigers are not allowed within Houston city limits unless the handler, such as a zoo, is licensed to have exotic animals, police said. Mr Borza said residents should not have such animals because they can be unpredictable. "If that tiger was to get out and start doing some damage yesterday [on Sunday], I'm sure one of these citizens would have shot the tiger. We have plenty of neighbours out here with guns, and we don't want to see that. "It's not the animal's fault. It's the breeder's fault. It's unacceptable," he said. (Webmaster's comment: This man is insane. Tigers see most humans as food!)
5-11-21 Scientists remotely controlled the social behavior of mice with light
The new devices allow complex wireless control of mouse brain activity. With the help of headsets and backpacks on mice, scientists are using light to switch nerve cells on and off in the rodents’ brains to probe the animals’ social behavior, a new study shows. These remote control experiments are revealing new insights on the neural circuitry underlying social interactions, supporting previous work suggesting minds in sync are more cooperative, researchers report online May 10 in Nature Neuroscience. The new devices rely on optogenetics, a technique in which researchers use bursts of light to activate or suppress the brain nerve cells, or neurons, often using tailored viruses to genetically modify cells so they respond to illumination (SN: 1/15/10). Scientists have used optogenetics to probe neural circuits in mice and other lab animals to yield insights on how they might work in humans (SN: 10/22/19). Optogenetic devices often feed light to neurons via fiber-optic cables, but such tethers can interfere with natural behaviors and social interactions. While scientists recently developed implantable wireless optogenetic devices, these depend on relatively simple remote controls or limited sets of preprogrammed instructions. These new fully implantable optogenetic arrays for mice and rats can enable more sophisticated research. Specifically, the researchers can adjust each device’s programming during the course of experiments, “so you can target what an animal does in a much more complex way,” says Genia Kozorovitskiy, a neurobiologist at Northwestern University in Evanston, Ill. These head-mounted and back-mounted devices are battery-free, wirelessly powered by the same high-frequency radio waves used to remotely control the intensity, duration and timing of the light pulses. The prototypes also allow scientists to simultaneously control four different neural circuits in an animal, thanks to LEDs that emit four hues — blue, green, yellow and red — instead of just one.
5-10-21 Taller and prettier plants are more likely to be studied by botanists
Plants that are taller and more attractive are more likely to be studied by botanists, suggests an analysis of research conducted over the past 45 years. Martino Adamo at the University of Turin in Italy and his colleagues analysed 280 scientific papers published between 1975 and 2020 that mention one or more of a selection of 113 small flowering plant species typical of the south-western Alps in Europe. Using a statistical model, they found that the physical appearance of a plant – its colour, the size of its flowers and the height of its stems – was the most important factor in explaining research interest amongst botanists, trumping ecological importance, rarity and abundance. Plants with blue flowers received the most attention. “Blue plants, such as Gentiana ligustica, in particular were really well studied,” says Adamo. Plants with white and red flowers were also significantly more researched than plants with brown and green flowers, which stand out the least from their background. “Looking at our model, plants taller than the average height in their habitat are more likely to be studied as well,” says Adamo. He and his team suggest that taller plants may have been more frequently examined because they are more accessible to researchers – they wouldn’t have to stoop to the ground to inspect the plant’s leaves, for instance. This may introduce a bias to botanical studies, as researchers are more likely to examine one type of plant than another, says Diego Fontaneto at Italy’s National Research Council. Adamo and his team hope to use these findings to inform better policies and conservation efforts aimed at avoiding the neglect of particular plants in the Alps. Although the analysis was only done on Alpine flora, the researchers are interested in investigating whether this pattern is seen in other ecosystems across the world.
5-7-21 Grand Canyon lottery to kill bison gathers 45,000 entries
Over 45,000 people have applied to cull bison in the Grand Canyon after the US National Park Service (NPS) requested volunteers to help with overpopulation. The famed national park in Arizona is seeking 12 "skilled volunteers" to reduce the herd, which has grown large enough to cause environmental damage. The event is not being classified as a "hunt", as hunting is forbidden in US national parks. Some environmentalists have warned the move could set a dangerous precedent. The lottery opened on Monday and closed after 48 hours with 45,040 applicants. An initial 25 names will be selected. After being vetted by park officials for skills including marksmanship, 12 people will be given the opportunity to kill a bison in the park's North Rim area. Volunteers are permitted to bring a support crew along, according to the NPS rules. Bison can weigh over 2,000lbs (900kg), but the sharp-shooters must carry out any meat on foot without the help of motorised transport or pack animals. The event will take place in rugged, rocky and sometimes snowy terrain, with elevations exceeding 8,000ft (2,440m). Officials say the pilot programme is required after the herd rapidly grew to 600 bison in recent years. The NPS hopes to bring the herd residing on the North Rim down to about 200 in order to reduce trampling of Native American archaeological sites, soil erosion and water contamination. Before being hunted to near-extinction in the 19th Century, bison (which are also known in the US as buffalo) roamed across much of the continent. An estimated 30 to 60 million bison were reduced to only about 400 by the late 1800s. But environmentalists say there is little evidence that the Grand Canyon was ever part of their historic range. According to historians, the North Rim herd was introduced to the area after a frontiersman's failed attempt to interbreed bison with cattle in the early 1900s.(Webmaster's comment: These are 45,000 very sick people!)
5-7-21 US Navy is developing drones to exterminate birds' eggs near airfields
A new US Navy autonomous drone will seek out and locate birds’ nests near airfields, armed with a device to prevent their eggs from hatching. Bird strikes are a serious risk to aircraft, and the US Pentagon spends around $50 million a year managing birds around airfields. Oiling is a process that involves coating eggs with food-grade oil and blocking pores in the shells to deprive embryos of oxygen. When carried out correctly, it is considered to be a humane way to prevent embryos from developing by the Human Society of the United States, and doesn’t drive parent birds to start a new nest or lay more eggs. The method can selectively reduce populations of ground-nesting birds while protecting threatened and endangered species. Drones have previously been used to locate birds’ nests that could then be treated by human operators, but many of these nests are in inaccessible places including cliff faces, towers or other infrastructure. Hitron Technologies in Lexington, Kentucky, is developing the Intelligent Remote Egg-Oiling System (IREOS) for the US Navy, in collaboration with the University of South Carolina. IREOS is a commercial quadcopter equipped with real-time nest detection based on deep learning, a form of machine learning inspired by the brain, and an egg-oiling device. IREOS autonomously manoeuvres around obstacles, such as power lines and antennas, while finding nests and eggs. Once a nest is located, a human operator then confirms whether to go ahead with oiling. IREOS should be able to tackle multiple nests in a 20-to-30-minute session on one battery charge. The IREOS prototype is currently carrying out flight tests in a controlled environment. Later field testing may require permits from the US Fish and Wildlife Service.
5-7-21 Rare fish set for return to River Severn breeding grounds
One of the UK's rarest fish is getting a chance to return to its historical breeding grounds on the River Severn. The little-known twaite shad, a member of the herring family, was once common in British waters with thousands of the fish migrating upstream in spring. Numbers dwindled after weirs constructed in the 19th Century posed barriers to migratory fish. A conservation project is trying to unlock the river for fish by creating routes around several weirs. It is hoped the move will benefit a host of species including salmon, lamprey and eels. This month could see the return of the twaite shad to stretches of the river north of Worcester. Volunteers are being sought to listen out for the distinctive splashing sounds the fish make when they breed at night. Jason Leach, programme director at the Canal & River Trust, said: "It's never too late to give nature the chance to recover. "Our project's night-time riverside spawning vigils are a fitting way to begin recording the recovery of the fish affected so badly when our predecessors inadvertently caused a big problem for migratory fish by the building of the weirs. "We hope lots of volunteers will be inspired to join us to witness and record the spring shad-spawning phenomenon." The Unlocking The Severn project by the Canal & River Trust, Severn Rivers Trust, Environment Agency and Natural England is in the process of reopening 150 miles (241km) of the river for the fish. Two specially constructed passes beside Victorian-era weirs at Diglis and Bevere, near Worcester, have been completed. A study by Swansea University estimates that 99% of the UK's rivers are fragmented by barriers such as weirs, dams, hydropower structures and culverts. The high number of barriers make it difficult for migratory fish to complete their journeys to reproduce and find food.
5-6-21 Many US cities will lose nearly all ash trees by 2060
An invasive pest called the emerald ash borer (Agrilus planipennis) will kill up to 99 per cent of the ash trees on the streets of many US cities by 2060, according to modelling by Emma Hudgins at McGill University in Canada and colleagues. Invasive pests and diseases, such as Dutch elm disease, have had a devastating impact on some types of tree in many places around the world. Hudgins has previously found that despite the different nature of these pests, it is relatively simple to model their spread because they are being carried around by people – in firewood, for instance. “Humans are doing the transport of these species,” she says. Hudgins’ team has now applied this finding to model how the spread of the pests already present in the US will affect street trees in cities. The researchers found the emerald ash borer is set to have the biggest impact. This Asian insect, first detected in in the US in 2002, attacks all native ash tree species. It is poised to wipe out most ashes in forests and will hit cities hard too. Some, including New York, Chicago, Cleveland and Philadelphia could lose 99 per cent of their ash trees, the model suggests. That means the loss of the many benefits of urban trees until replacements grow. Greener cities are good for people’s mental well-being, Hudgins says, and trees provide habitat for animals, too. They also cool places in summer, improving the health of those who can’t afford air conditioning and reducing the bills of those who can. Clearing dead ash trees could cost each city up to $13 million, the team forecast. “If they fall on someone that’s a huge liability,” Hudgins says. Cities replanting trees or planting new ones should plant a diverse mix of pest-resistant species, she says, rather than having streets lined with genetically identical trees.
5-6-21 Income inequality 'drives global wildlife trade'
More than 420 million wild animals have been traded in 226 nations over two decades, according to new figures. Researchers say income inequality is driving the trade and suggest high-income countries should pay poorer ones to conserve wildlife. The international trade in animals and plants stands as one of the biggest threats to endangered species. The analysis shows wild animals are mostly moved from low-income countries to rich developed nations. For instance, wild frogs are traded between Madagascar and the US, and wild fish exported from Thailand to Hong Kong. Researchers argue that the lack of socioeconomic incentives in current multi-national agreements may be limiting the potential to crackdown on harmful trade. Jia Huan Liew of the University of Hong Kong, who led the study, said countries supplying the most wildlife products should be given financial incentives to reduce trade over a set time period. "At the end of this period, the exporting country will receive a pre-agreed sum if the target is met," he told BBC News. "Funding would ideally be drawn from wealthy countries, given their commitment to the UN Sustainable Development Goals (SDG), and the fact that they play a disproportionately large role in the global wildlife market." The researchers believe the pandemic could lead to a decline in international wildlife trade, due to a number of factors including bans on wildlife consumption in China. They say this should be viewed as the foundation for change. "To avoid returning to business as usual, we should take advantage of the public's awareness of the possible consequences of consuming wildlife products to reduce demand, and make the Chinese ban on wildlife consumption permanent," Dr Liew said. The study, published in Science Advances, found that between 1998 and 2018, the global trade network was more extensive among pairs of nations with greater wealth divides. The largest exporters of wildlife products were Indonesia, Jamaica and Honduras, while the US was the biggest importer, with France and Italy a distant second and third.
5-5-21 The platypus: What nature’s weirdest mammal says about our origins
Platypuses glow in UV light, produce venom and lay eggs. Yet despite their oddities, their newly sequenced genome illuminates the evolution of mammals. WHEN news reached London of a mole-like animal with webbed feet and a duck’s bill, many people thought it was a hoax. It was the late 18th century, Britain had just begun colonising Australia and the strange creature had been spotted by no less a figure than David Collins, founder of New South Wales. However, when zoologist George Shaw at the British Museum examined sketches and specimens of the animal, he was sceptical. “It naturally excites the idea of some deceptive preparation by artificial means,” he wrote. Attitudes changed as more specimens arrived. In 1799, Shaw was the first to scientifically describe the creature, giving it the name Platypus anatinus, meaning “flat-footed duck”. It was later referred to as the “paradoxical bird-snout” before being officially renamed Ornithorhynchus anatinus, meaning “duck-like bird snout”. Today, most people just call it the platypus. It took more than 80 years just to work out how this animal fits into the tree of life. Since then, biologists have gone even further and found that it possesses a range of features that mean it is among the most unusual creatures on Earth. But it isn’t simply an oddity. As a mammal that shares many characteristics with birds and reptiles, the platypus holds the key to unlocking some fundamental evolutionary mysteries. Now, geneticists have mapped its entire genome and are starting to understand how it came to be so strange – and what it can tell us about the origins of all mammals, including us. Even today, it turns out, the platypus has the ability to surprise. The platypus is one of just five remaining species from an ancient group of mammals called monotremes that lay eggs rather than giving birth to live young, as other mammals do. The other extant monotremes, the four species of echidna, are equally strange. Found only in waterways across Tasmania and eastern Australia, platypuses are nocturnal and grow to about half a metre long. They may look like a mash-up of various animals, but, ecologically, they make sense. “They are exquisitely adapted to what they do,” says biologist Jonathan Losos at Washington University in St Louis, Missouri. Their webbed feet, sprawled body and dense, waterproof fur are perfect for their semi-aquatic lifestyle. Their claws make them efficient diggers: they excavate tunnels around 5 metres long in riverbanks in which to live. And platypuses’ distinctive, duck-like bills allow them to search for crustaceans and insects while swimming underwater with their eyes, ears and noses shut. “It has this amazing electroreception sense in its bill that can detect the muscular activity of its prey, even slight muscle twitches,” says Losos.
5-5-21 Ant species given first gender-neutral scientific name
A newly discovered species of ant from Ecuador has been named with the suffix “-they”, rather than a traditional gendered Latin suffix, to celebrate gender diversity. The ant was discovered by Philipp Hoenle at the Technical University of Darmstadt, Germany, in 2018. He sent a photograph to taxonomic expert Douglas Booher at Yale University, who recognised it as a new species in the genus Strumigenys. In contrast to traditional species-naming practices, which only recognise one of two distinct genders with the suffixes “-ae” for women and “-i” for men, Booher suggested using the gender non-binary identifier “they” instead, naming the ant Strumigenys ayersthey after artist and human rights activist Jeremy Ayers. Ayers was a protégé of Andy Warhol in the 1970s under the pseudonym of Silva Thinn. He died in 2016. “He identified as a gay man outside of his Warhol character, but I’m naming it after him with the suffix added to include all non-binary people for his activism,” says Booher. Booher also asked Michael Stipe, the lead singer of the band R.E.M. and a mutual friend with Ayers, to join him in writing the etymology section of the paper outlining the new species. According to Booher, there are 853 species in the Strumigenys genus, but the new ant was immediately identifiable as unique. “It’s very different from any ant in the genus,” he says. “There’s a lot of convergent evolution, so a lot of species in different countries look alike but aren’t related. So it was a special ant and I was waiting for something like this to represent gender diversity and biological diversity.” Asked whether he will use the -they suffix to name future new species, Booher says he will use a female, male or non-binary suffix depending on the wishes of the person the species is named after.
5-5-21 Floating googly eyes on a stick scare seabirds away from fishing nets
Buoys fitted with cartoon-like eyes act in a similar way to scarecrows, keeping seabirds safely away from areas of the sea where they might get caught in fishing nets. An estimated 400,000 diving birds drown each year when they become entangled in vertically oriented gill nets that hang down in water between floats or buoys. In a bid to reduce deaths, a team of bird conservation researchers led by Yann Rouxel at the BirdLife International Marine Programme in Glasgow, UK, has developed and tested a method of turning the buoys into marine scarecrows. Researchers previously hoped that LED lighting would alert seabirds to the nearly transparent nets, but the birds got tangled up and drowned anyway, says Rouxel. Then he and his team noticed that digital, moving eyes on the screens surrounding airport runways successfully keep birds away from planes. Rouxel and his colleagues decided to adapt the concept for use by the fishing industry, with a device that needs no electricity to run and is both lightweight and inexpensive. Based on previous studies about seabird vision and what changes their flight patterns and brain activity, the researchers created a Looming-Eyes Buoy (LEB) prototype out of carbon and steel. It features a panel that rotates in the wind like a weather vane. On one side of the panel, the researchers added a small pair of eyes; on the opposite side, they added a larger pair of eyes, so that as the device spins it gives the impression of a strange creature that is appearing, or looming, in the field of vision. “The wind changes a lot, so that creates a looming-eye movement that is hard to predict and could keep the birds from habituating [getting used to the threat] too quickly,” says Rouxel. This sort of looming phenomenon has been shown to trigger “collision neurons” in bird brains that prevent them from running into objects or each other, he says.
5-4-21 A species of yeast produces near-identical clones when it has sex
A species of yeast has weird sex. While most organisms use sex to reshuffle their genes and create offspring that are genetically different from their parents, this one goes to extreme lengths to avoid recombining its DNA. The yeast, called Saccharomycodes ludwigii, illustrates a problem that all sexually reproducing species face: while sex has evolutionary benefits, it also has costs. In some circumstances, reshuffling genes can produce individuals that can’t survive, so it is better not to do it too much. “This species is an extreme case,” says Michael Knop at Heidelberg University in Germany. Knop and his colleagues have spent more than a decade studying S. ludwigii. Like other yeasts, it is a single-celled fungus and can reproduce sexually. They do this through a process called meiosis: a yeast species starts out with two copies of every chromosome, and therefore two copies of every gene. Each “adult” cell then shuffles genes between its chromosomes through a process called recombination, before producing daughter cells that carry just one copy of each chromosome. Because of the recombination, the chromosomes that these daughter cells carry are genetically distinct from those present in the adult – and so when two such daughter cells fuse together to form offspring with two copies of every chromosome, these offspring will also be genetically distinct from the original adults. But this isn’t the case in S. ludwigii. Knop and his team found that this yeast hardly ever performs recombination. They sequenced parent and offspring yeast and couldn’t find any pieces of chromosome that had been swapped. This result held true when the researchers examined 10 different strains of the species, suggesting that it has behaved this way for a long time. It isn’t that S. ludwigii can’t perform recombination – the researchers found that it still has the majority of the genes required to do so.
5-3-21 Bats don’t have to learn the speed of sound – they’re born knowing it
Bats are born knowing the speed of sound. This may not be shocking, as they rely on echolocation to find food and avoid crashing into trees in the dark. But unlike birds that learn their songs, or lions that learn to hunt, bats seem to be born knowing how to echolocate. Bats make high-pitched calls that reflect off distant objects, and then they translate the time until the echo returns into some measure of distance. Depending on air temperature, sound can move faster or slower, and it is a reasonable expectation that bats would accommodate for this. To see whether bats can adjust their echolocation to accommodate changes in the speed of sound, Eran Amichai and Yossi Yovel at Tel Aviv University in Israel trained eight adult Kuhl’s pipistrelle bats (Pipistrellus kuhlii) to fly to a perch within a chamber pumped full of oxygen and helium. Because helium is less dense than other atmospheric gases, sound travels faster through it. The helium interfered with the bats’ echolocation timing and caused them to aim short of the perch. At first, this was expected, but the adult bats never learned to adjust. “We were surprised by the results. Honestly, we didn’t trust them at first,” says Amichai, now at Dartmouth College in New Hampshire. Amichai and Yovel then tried the experiment with pups instead of adults. They hand-reared 11 bats, raising half of them from birth in the helium-enriched chamber. When the bats were old enough to fly, Amichai trained the pups to fly to the perch like the adults. Still, despite the environment the pups were raised in, neither group could accurately sense the distance to the perch in the helium environment. Both experiments indicate that bats have a rigid, innate reference for the speed of sound. The team says they expect this to be the same in all bats, as the brain structures involved in echolocation are similar across species.
5-3-21 Nanoscale nutrients can protect plants from fungal diseases
Tuning the chemistries of nanomaterials changes the plants’ response levels to fungal pathogens. Chances are, most — if not all — of the produce in your kitchen is threatened by fungal diseases. The threat looms large for food staples of the world such as rice, wheat, potatoes and maize (SN: 9/22/05). Pathogenic fungi are also coming for our coffee, sugarcane, bananas and other economically important crops. Annually, fungal diseases destroy a third of all harvests and pose a dire threat to global food security. To stop the spread of fungal diseases, farmers fumigate the soil with toxic chemicals that lay waste to the land, sparing not even the beneficial microbes teeming in the earth. Or they ply plants with fungicides. But fungicide use is effective only in the short run — until the pathogenic fungi evolve resistance against these synthetic chemicals. Now, a new idea is taking root: Help plants stand their ground by giving them the tools to fight their own battles. A team led by Jason White, an environmental toxicologist at the Connecticut Agricultural Experiment Station in New Haven, is fortifying crops with nutrients fashioned into nanosized packages, which boost plants’ innate immunity against pathogenic fungi more efficiently than traditional plant feeding. Over the past few years, the researchers have devised various nanonutrient concoctions that boost the fungal resistance of soybeans, tomatoes, watermelons and, recently, eggplants, as reported in the April Plant Disease. The concept “tackles the challenge at the origin rather than trying to put a Band-Aid on the [problem],” says Leanne Gilbertson, an environmental engineer at the University of Pittsburgh who was not involved in the research. White’s strategy provides plants with the nutrients they need to trigger enzyme production to guard against pathogenic attack. Without any synthetic chemicals introduced, the strategy sidesteps any opportunity for malignant fungi to develop resistances, she says.