Saturday, October 24, 2015
Friday, October 23, 2015
How street trees can save our cities
Introducing 'treeconomics': how street trees can save our cities
As a fight over 11 lime trees in Sheffield escalates, activists in cities all over the world are making the case for urban trees – to cut pollution, increase land value and even make you feel younger
Plane trees in London. In the last seven years, the city has planted 20,000 trees. Photograph: Alamy
Guardian Cities is supported by:About this content
Patrick Barkham
@patrick_barkham
Saturday 15 August 2015 08.00 BSTLast modified on Saturday 15 August 201508.43 BST
Rustlings Road is aptly named. The street in Sheffield is lined with mature lime trees. Their whispering leaves are brilliant green in spring, then cast cool, dappled shade in summer and turn bright yellow in the autumn. But Sheffieldcity council wants to prune the street, and a dispute about 11 lime trees has turned into a citywide campaign, with more than 10,000 people urging the council to halt its roadside felling. I has also sparked a broader debate about what 36,000 street trees bring to a place that claims to be the most wooded industrial city in western Europe.
This tussle shows how urban trees are both treasured and in jeopardy like never before – beset by disease and spurious insurance claims, and too readily felled by cash-strapped local authorities which only see their potential cost rather than their contribution to climate, public health and even the wealth of a city. Ever since Roger Ulrich discovered in 1984 that hospital patients appear to recover more quickly from surgery in rooms with green views, a growing body of scientific evidence has demonstrated the health – and wealth – benefits of trees in cities.
In Toronto, researchers recently found that people living on tree-lined streetsreported health benefits equivalent to being seven years younger or receiving a $10,000 salary rise. As well as studies revealing benefits from everything from improved mental health to reduced asthma, US scientists have even identified a correlation between an increase in tree-canopy cover and fewer low-weight births. And economic studies show what any estate agent swears by: leafy streets sell houses. Street trees in Portland, Oregon, yielded an increase in house pricesof $1.35bn, potentially increasing annual property tax revenues by $15.3m
Despite compelling scientific support for urban greenery, the trees on British streets are imperilled by the lack of any government department or national body to look after them (unlike government-owned woodlands, which are managed by the Forestry Commission). Urban trees stand at the mercy of cash-strapped local councils and a hotchpotch of agencies, from housing associations to highway authorities, who may overlook their true value. But as Sheffield residents mount a desperate defence of their mature street trees, some councils and planners seem to have grasped the value of their urban forest.
In Brighton, tree experts from across Europe gathered last month and called for World Heritage Status to be given to one of the city’s less feted attractions – its unique population of mature elm trees, which survived the Dutch elm disease that destroyed most of the species in the 1970s. London mayor Boris Johnson has planted 20,000 street trees in seven years, but this achievement – praised by tree experts – is dwarfed by Toronto’s mayor John Tory, who has planted 40,000 trees since his election victory last December and has promised 3.8m over the next decade.
City trees are now being mapped with new accuracy, showing the abundance of different species that line avenues everywhere from New York and Washington to the London borough of Southwark.
The location of street trees on public land managed by Southwark council. Photograph: OpenStreetMap
In London, an innovative survey will reveal the economic value of the capital’s “urban forest” – its estimated 8m trees. A suite of open-source software developed in the US called i-Tree maps city trees and calculates the financial value of the “ecosystem services” they provide. While street trees are a visible green stamp on a city, 70% of the “urban forest” is found in private gardens and places such as railway embankments, cemeteries and golf courses. i-Tree measures them all and, crucially, calculates tree canopy cover. It’s all then given a hard-headed financial value based on the carbon they store, the air pollution they remove, the rainwater they hold (allowing it to be re-evaporated by the sun rather than disappearing into drains and sewers) and how they ameliorate extreme temperatures. Trees that are close to buildings reduce air conditioning in summer, and even heating bills in winter – small effects that become extremely valuable in a big city.
The software has been deployed in European cities including Edinburgh, Barcelona and Strasbourg. Torbay in Devon was the first British council to trial it: the English Riviera resort famed for its palms discovered that its trees (mostly ash) stored 98,000 tonnes of carbon and removed 50 tonnes of air pollution each year - the equivalent of taking 52,000 family cars off the road. i-Tree showed that Torbay trees’ carbon storage was worth £1.5m, their pollution removal £1.3m, and the cost to replace them would be £280m. These facts helped the council’s tree officer win more funding for planting and maintaining its trees.
Urban trees stand at the mercy of cash-strapped local councils... who may overlook their true value
Jake Tibbetts, a committee member of the London Tree Officers’ Association, has led i-Tree surveys across London, using volunteers to reduce costs (a survey typically costs £30,000–£50,000 according to Treeconomics, the social enterprise that brought i-Tree to Britain). “One of the good things about trees is that people are passionate about them. If we were surveying street lamps and bollards it would be a lot harder to find volunteers,” says Tibbetts. He was surprised by what the surveys revealed: one of the commonest trees in central London is actually the apple tree, hidden in gardens.
Tibbets says: “i-Tree is a real opportunity to finally put a valuation on London’s tree resource and financial value is something that everybody can understand.” The survey isn’t truly comprehensive – it doesn’t calculate mental or physical health benefits, for instance, or the cultural value of trees – but Tibbetts is hopeful it will raise awareness of the “significant threat” to London’s urban forest. “Insurance claims [for roots causing building subsidence or uneven pavements that lead to accidents] are a large financial risk for local authorities, but for urban forests the main threat is development and complacency,” he says. “We believe we come from a green and pleasant land with lots of trees – when developers remove two trees, we think there are lots more.”
FacebookTwitterPinterest Street trees planted by Washington DC’s District Urban Forest Administation.
London’s i-Tree results will be published this autumn, and will prove that the capital’s trees are a multimillion-pound piece of infrastructure, but they will also show that the city has a problem – its dependance on London plane trees. These majestic giants give great pleasure to visitors to Westminster and the City and perform a vital practical role, too. Tibbetts recorded the temperature on London streets during the recent heatwave, and found that temperatures were 10C lower under the shade of grand planes than in the open street. “That’s going to be really important when temperatures increase with climate change,” says Tibbetts. “Trees are a low-cost way to make the city a comfortable place to live and work.”
According to Kenton Rogers of Treeconomics, no more than 10% of trees on one street should be of the same species. A Treeconomics survey found that 30% of all trees in London Victoria’s business improvement district were London planes, and because they are so big, they perform 60% of the ecosystem services in Victoria. “With climate change and the globalisation of pests and diseases,London is a bit more vulnerable than somewhere with a more diverse treescape,” says Rogers.
Disease is perhaps the most terrifying threat to London planes. A wilt disease has struck thousands of mature trees in France, and has now spread as far north as Lille. If it crosses the Channel, it would change the capital perhaps as dramatically as the blitz. But if it doesn’t, ageing plane trees will still have to be replaced. Rogers’ study of Victoria found that most were being substituted with species that won’t grow as large, and will never perform the valuable services that big planes do.
FacebookTwitterPinterest Plane trees might be London’s most famous tree, but the city’s most common species is the apple tree, mainly hidden in gardens. Photograph: Robert Hardi/REX Shutterstock/Robert Hardi/REX Shutterstock
Keith Sacre of Barcham Trees, the largest container tree nursery in Europe, supplying more than 60,000 each year, says the standard street trees they sell to London boroughs are 3.5m high with a 14cm girth. He calculates that to replicate the leaf area of just one mature plane tree on the Embankment, 60 new trees would have to be planted. “One-for-one replacement is mad,” he says. “Planting has got to be slow, steady, planned and resourced. There has to be a long-term commitment to recognising trees as the asset that they are.”
Unfortunately, the replacement of mature trees with dainty ornamental species is a trend across many cities, creating “lollipop landscapes” according to Mark Johnston, author of Trees in Towns and Cities. “Local authorities are cutting back on their spending on tree maintenance and management so tree officers are reluctant to put in large trees. They’ll put in little lollipop trees that don’t contribute much to the landscape or deliver much in terms of ecosystem services.”
Authorities put in little 'lollipop trees' that don’t contribute much to the landscapeIan Rotherham
Terry Fox, cabinet member for the environment and transport at Sheffield city council, says it is a “myth” that removing mature trees is the cheapest option. The council says cannot reveal the comparative cost of removal and maintenance because it simply pays an annual charge for all services delivered under the contract, of which tree maintenance is one. “Sheffield is the greenest city in the UK, with more than two million trees – four for every person. This is something we are all very proud of. To help preserve our green status we have also, this year alone, planted 50,000 trees, creating 17 new woodlands,” says Fox in a statement. “The removal of any tree is always a last resort and we look at all viable options before removal is considered.”
In 2007, a survey suggested that 75% of Sheffield’s roadside trees were approaching the end of their natural life. The council’s tree-management policy is to remove and replace roadside trees that are dangerous, dead, dying, diseasedand damaging to the road or pavement, or cause “discrimination”. By this, the council means where roots damage pavements and potentially obstruct disabled or partially sighted residents. On Rustlings Road, however, campaigners filmed two mobility scooters travelling side-by-side, safely passing along the pavement below the “discriminatory” trees earmarked for destruction. “We’ve got a couple of “Ds” as well”, says local resident Louise Wilcockson. “We think the council’s response is disproportionate and they can use some professional discretion over the ‘dangerous’ trees.”
Green city: share your photos and stories of urban trees
Sheffield city council has now established a “tree forum” for experts and residents to discuss plans for a city tree strategy next March. “We’re delighted, but how many trees will be cut down before then?” says Wilcockson, who is sceptical about the forum. As Fox puts it in his statement, it is “to enable the public to better understand our approach to managing the city’s street trees”. He confirms that the council is still planning to remove the 11 limes on Rustlings Road, and will replace these and plant nine additional trees on the street.
“This is not a parochial issue, it’s a huge issue about privatising local authority services,” says Rotherham, who has been contacted by residents in Birmingham, Southampton and Leicester also concerned about councils removing mature trees. “In Sheffield, the cost is [to] the tree resource, the value of Sheffield PLC, and the local people who are really, really upset. We shouldn’t belittle that - we know that trees make people happier and healthier.”
Follow Guardian Cities on Twitter and Facebook and join the discussion
Topics
Trees and forests
Local government
Wildlife
Sheffield
London
Guardian Cities is supported by:About this content
Patrick Barkham
@patrick_barkham
Saturday 15 August 2015 08.00 BSTLast modified on Saturday 15 August 201508.43 BST
Rustlings Road is aptly named. The street in Sheffield is lined with mature lime trees. Their whispering leaves are brilliant green in spring, then cast cool, dappled shade in summer and turn bright yellow in the autumn. But Sheffieldcity council wants to prune the street, and a dispute about 11 lime trees has turned into a citywide campaign, with more than 10,000 people urging the council to halt its roadside felling. I has also sparked a broader debate about what 36,000 street trees bring to a place that claims to be the most wooded industrial city in western Europe.
This tussle shows how urban trees are both treasured and in jeopardy like never before – beset by disease and spurious insurance claims, and too readily felled by cash-strapped local authorities which only see their potential cost rather than their contribution to climate, public health and even the wealth of a city. Ever since Roger Ulrich discovered in 1984 that hospital patients appear to recover more quickly from surgery in rooms with green views, a growing body of scientific evidence has demonstrated the health – and wealth – benefits of trees in cities.
In Toronto, researchers recently found that people living on tree-lined streetsreported health benefits equivalent to being seven years younger or receiving a $10,000 salary rise. As well as studies revealing benefits from everything from improved mental health to reduced asthma, US scientists have even identified a correlation between an increase in tree-canopy cover and fewer low-weight births. And economic studies show what any estate agent swears by: leafy streets sell houses. Street trees in Portland, Oregon, yielded an increase in house pricesof $1.35bn, potentially increasing annual property tax revenues by $15.3m
.
FacebookTwitterPinterest Lime tree roots forcing up tarmac. The proposal to fell 11 of them on Rustling Road has sparked a major dispute. Photograph: AlamyDespite compelling scientific support for urban greenery, the trees on British streets are imperilled by the lack of any government department or national body to look after them (unlike government-owned woodlands, which are managed by the Forestry Commission). Urban trees stand at the mercy of cash-strapped local councils and a hotchpotch of agencies, from housing associations to highway authorities, who may overlook their true value. But as Sheffield residents mount a desperate defence of their mature street trees, some councils and planners seem to have grasped the value of their urban forest.
In Brighton, tree experts from across Europe gathered last month and called for World Heritage Status to be given to one of the city’s less feted attractions – its unique population of mature elm trees, which survived the Dutch elm disease that destroyed most of the species in the 1970s. London mayor Boris Johnson has planted 20,000 street trees in seven years, but this achievement – praised by tree experts – is dwarfed by Toronto’s mayor John Tory, who has planted 40,000 trees since his election victory last December and has promised 3.8m over the next decade.
City trees are now being mapped with new accuracy, showing the abundance of different species that line avenues everywhere from New York and Washington to the London borough of Southwark.
In London, an innovative survey will reveal the economic value of the capital’s “urban forest” – its estimated 8m trees. A suite of open-source software developed in the US called i-Tree maps city trees and calculates the financial value of the “ecosystem services” they provide. While street trees are a visible green stamp on a city, 70% of the “urban forest” is found in private gardens and places such as railway embankments, cemeteries and golf courses. i-Tree measures them all and, crucially, calculates tree canopy cover. It’s all then given a hard-headed financial value based on the carbon they store, the air pollution they remove, the rainwater they hold (allowing it to be re-evaporated by the sun rather than disappearing into drains and sewers) and how they ameliorate extreme temperatures. Trees that are close to buildings reduce air conditioning in summer, and even heating bills in winter – small effects that become extremely valuable in a big city.
The software has been deployed in European cities including Edinburgh, Barcelona and Strasbourg. Torbay in Devon was the first British council to trial it: the English Riviera resort famed for its palms discovered that its trees (mostly ash) stored 98,000 tonnes of carbon and removed 50 tonnes of air pollution each year - the equivalent of taking 52,000 family cars off the road. i-Tree showed that Torbay trees’ carbon storage was worth £1.5m, their pollution removal £1.3m, and the cost to replace them would be £280m. These facts helped the council’s tree officer win more funding for planting and maintaining its trees.
Urban trees stand at the mercy of cash-strapped local councils... who may overlook their true value
Jake Tibbetts, a committee member of the London Tree Officers’ Association, has led i-Tree surveys across London, using volunteers to reduce costs (a survey typically costs £30,000–£50,000 according to Treeconomics, the social enterprise that brought i-Tree to Britain). “One of the good things about trees is that people are passionate about them. If we were surveying street lamps and bollards it would be a lot harder to find volunteers,” says Tibbetts. He was surprised by what the surveys revealed: one of the commonest trees in central London is actually the apple tree, hidden in gardens.
Tibbets says: “i-Tree is a real opportunity to finally put a valuation on London’s tree resource and financial value is something that everybody can understand.” The survey isn’t truly comprehensive – it doesn’t calculate mental or physical health benefits, for instance, or the cultural value of trees – but Tibbetts is hopeful it will raise awareness of the “significant threat” to London’s urban forest. “Insurance claims [for roots causing building subsidence or uneven pavements that lead to accidents] are a large financial risk for local authorities, but for urban forests the main threat is development and complacency,” he says. “We believe we come from a green and pleasant land with lots of trees – when developers remove two trees, we think there are lots more.”
London’s i-Tree results will be published this autumn, and will prove that the capital’s trees are a multimillion-pound piece of infrastructure, but they will also show that the city has a problem – its dependance on London plane trees. These majestic giants give great pleasure to visitors to Westminster and the City and perform a vital practical role, too. Tibbetts recorded the temperature on London streets during the recent heatwave, and found that temperatures were 10C lower under the shade of grand planes than in the open street. “That’s going to be really important when temperatures increase with climate change,” says Tibbetts. “Trees are a low-cost way to make the city a comfortable place to live and work.”
According to Kenton Rogers of Treeconomics, no more than 10% of trees on one street should be of the same species. A Treeconomics survey found that 30% of all trees in London Victoria’s business improvement district were London planes, and because they are so big, they perform 60% of the ecosystem services in Victoria. “With climate change and the globalisation of pests and diseases,London is a bit more vulnerable than somewhere with a more diverse treescape,” says Rogers.
Disease is perhaps the most terrifying threat to London planes. A wilt disease has struck thousands of mature trees in France, and has now spread as far north as Lille. If it crosses the Channel, it would change the capital perhaps as dramatically as the blitz. But if it doesn’t, ageing plane trees will still have to be replaced. Rogers’ study of Victoria found that most were being substituted with species that won’t grow as large, and will never perform the valuable services that big planes do.
Keith Sacre of Barcham Trees, the largest container tree nursery in Europe, supplying more than 60,000 each year, says the standard street trees they sell to London boroughs are 3.5m high with a 14cm girth. He calculates that to replicate the leaf area of just one mature plane tree on the Embankment, 60 new trees would have to be planted. “One-for-one replacement is mad,” he says. “Planting has got to be slow, steady, planned and resourced. There has to be a long-term commitment to recognising trees as the asset that they are.”
Unfortunately, the replacement of mature trees with dainty ornamental species is a trend across many cities, creating “lollipop landscapes” according to Mark Johnston, author of Trees in Towns and Cities. “Local authorities are cutting back on their spending on tree maintenance and management so tree officers are reluctant to put in large trees. They’ll put in little lollipop trees that don’t contribute much to the landscape or deliver much in terms of ecosystem services.”
Authorities put in little 'lollipop trees' that don’t contribute much to the landscapeIan Rotherham
This, say residents of Sheffield, is exactly what is happening in their city. Ian Rotherham, professor of environmental geography at Sheffield Hallam, says the removal of street trees is the consequence of nearly a decade of austerity. “Big metropolitan districts have been seriously disadvantaged by the coalition and the current government reducing the amount of money they get per capita. The solution to really severe cuts has been public-private partnerships,” he argues. In Sheffield, the council signed a 25-year PFI contract with Amey in 2012 to manage and improve its roads, including greenery. Rotherham and other campaigners argue that Amey’s removal of mature urban trees is because it’s the cheapest option, minimising expensive pruning costs and damage to pavements. But requests for information about the costs of tree removal have been frustrated by “commercial confidentiality” cited by the council and its contractors. “Without any public consultation or awareness, we’ve somehow got locked into this situation where there’s a 25-year agreement about our green infrastructure in which local people have no say,” says Rotherham.
FacebookTwitterPinterest ‘It’s a myth that removing mature trees is the cheapest option’ ... trees in the London borough of Barnet. Photograph: Karen RobinsonTerry Fox, cabinet member for the environment and transport at Sheffield city council, says it is a “myth” that removing mature trees is the cheapest option. The council says cannot reveal the comparative cost of removal and maintenance because it simply pays an annual charge for all services delivered under the contract, of which tree maintenance is one. “Sheffield is the greenest city in the UK, with more than two million trees – four for every person. This is something we are all very proud of. To help preserve our green status we have also, this year alone, planted 50,000 trees, creating 17 new woodlands,” says Fox in a statement. “The removal of any tree is always a last resort and we look at all viable options before removal is considered.”
In 2007, a survey suggested that 75% of Sheffield’s roadside trees were approaching the end of their natural life. The council’s tree-management policy is to remove and replace roadside trees that are dangerous, dead, dying, diseasedand damaging to the road or pavement, or cause “discrimination”. By this, the council means where roots damage pavements and potentially obstruct disabled or partially sighted residents. On Rustlings Road, however, campaigners filmed two mobility scooters travelling side-by-side, safely passing along the pavement below the “discriminatory” trees earmarked for destruction. “We’ve got a couple of “Ds” as well”, says local resident Louise Wilcockson. “We think the council’s response is disproportionate and they can use some professional discretion over the ‘dangerous’ trees.”
Sheffield city council has now established a “tree forum” for experts and residents to discuss plans for a city tree strategy next March. “We’re delighted, but how many trees will be cut down before then?” says Wilcockson, who is sceptical about the forum. As Fox puts it in his statement, it is “to enable the public to better understand our approach to managing the city’s street trees”. He confirms that the council is still planning to remove the 11 limes on Rustlings Road, and will replace these and plant nine additional trees on the street.
“This is not a parochial issue, it’s a huge issue about privatising local authority services,” says Rotherham, who has been contacted by residents in Birmingham, Southampton and Leicester also concerned about councils removing mature trees. “In Sheffield, the cost is [to] the tree resource, the value of Sheffield PLC, and the local people who are really, really upset. We shouldn’t belittle that - we know that trees make people happier and healthier.”
Follow Guardian Cities on Twitter and Facebook and join the discussion
Topics
Trees and forests
Local government
Wildlife
Sheffield
London
Thursday, October 22, 2015
The benefits of conserving nature
The staggeringly large benefits of conserving nature http://wpo.st/CwnQ0 @chriscmooney via @washingtonpost #conservation
Chris Mooney
@chriscmooney
Energy and environment writer at @washingtonpost, also tweeting at @postgreen.
Post Green
@postgreen
The Washington Post's environment, climate change, and energy coverage. Tweets by @chriscmooney.
Washington, D.C.
Joined April 2008
Energy and Environment
The staggeringly large benefits of conserving nature
By Chris Mooney July 13
This is the latest installment of a weekly column on energy and the environment — “Planetary.” This column will draw together major trends in this sphere and provide analysis and perspective that extend beyond our daily reporting.
In the past few weeks, as I’ve written about research showing that living near trees has demonstrable benefits to your health, and that nature walks might help battle depression, I’ve noticed a recurrent reaction from readers.
The top response seems to be some variant of, “duh, we knew that already.” In other words, a lot of people think it’s obvious that nature experiences are healthy and fulfilling.
[New research suggests nature walks are good for your brain]
And yet at the same time, these articles are being shared pretty widely. It seems the beneficial effect of nature is both something that we feel we already recognize — and yet also something we think others still need to know.
In a way, that’s not so surprising. The human connection to nature is ancient and, probably, part of the wiring of our brains. So in this sense, yes, it is obvious that greenery is good for us.
But it’s also indisputable that we don’t always act like we realize this. Across the globe, forests are burning or crashing down, species are vanishing, and the globe’s human population is more and more concentrated in urban areas and megacities. However much we appreciate nature, it isn’t enough to make us rein in other tendencies, especially economic imperatives, that ultimately fuel environmental and ecosystem destruction, as well as a disconnection from the natural world.
That’s a longstanding tension — but if there’s anything new to this dynamic of late, it’s a wave of science that is finally pinning down the true cost of damaging our natural surroundings — and the true benefits of preserving or expanding them. After all, it’s one thing to say you like the outdoors — who doesn’t? — and quite another to learn about findings like one reported last week: An increase of 11 trees on a city block is comparable, in terms of improved cardio-metabolic health, to raising people’s income by $20,000 or making them 1.4 years younger.
[Scientists have discovered that living near trees is good for your health]
Source: http://www.washingtonpost.com/news/energy-environment/wp/2015/07/13/were-finally-starting-to-realize-what-nature-is-really-worth/?postshare=8831436997694431
By Chris Mooney July 13
This is the latest installment of a weekly column on energy and the environment — “Planetary.” This column will draw together major trends in this sphere and provide analysis and perspective that extend beyond our daily reporting.
In the past few weeks, as I’ve written about research showing that living near trees has demonstrable benefits to your health, and that nature walks might help battle depression, I’ve noticed a recurrent reaction from readers.
The top response seems to be some variant of, “duh, we knew that already.” In other words, a lot of people think it’s obvious that nature experiences are healthy and fulfilling.
[New research suggests nature walks are good for your brain]
And yet at the same time, these articles are being shared pretty widely. It seems the beneficial effect of nature is both something that we feel we already recognize — and yet also something we think others still need to know.
In a way, that’s not so surprising. The human connection to nature is ancient and, probably, part of the wiring of our brains. So in this sense, yes, it is obvious that greenery is good for us.
But it’s also indisputable that we don’t always act like we realize this. Across the globe, forests are burning or crashing down, species are vanishing, and the globe’s human population is more and more concentrated in urban areas and megacities. However much we appreciate nature, it isn’t enough to make us rein in other tendencies, especially economic imperatives, that ultimately fuel environmental and ecosystem destruction, as well as a disconnection from the natural world.
That’s a longstanding tension — but if there’s anything new to this dynamic of late, it’s a wave of science that is finally pinning down the true cost of damaging our natural surroundings — and the true benefits of preserving or expanding them. After all, it’s one thing to say you like the outdoors — who doesn’t? — and quite another to learn about findings like one reported last week: An increase of 11 trees on a city block is comparable, in terms of improved cardio-metabolic health, to raising people’s income by $20,000 or making them 1.4 years younger.
[Scientists have discovered that living near trees is good for your health]
Source: http://www.washingtonpost.com/news/energy-environment/wp/2015/07/13/were-finally-starting-to-realize-what-nature-is-really-worth/?postshare=8831436997694431
Tuesday, October 20, 2015
Why Killing a Bull Elephant With Big Tusks Hurts the Herd
Elephants
with large tusks, such as this one in Tanzania, are increasingly rare
because of heavy poaching, making them even more valuable to trophy
hunters. With elephant numbers in free-fall in many places, losing even
one big tusker is damaging to a herd.
Photograph by Mitsuaki Iwago, Minden Pictures/National Geographic
Why Killing a Bull Elephant With Big Tusks Hurts the Herd
Scientists say the loss of a mature bull elephant has a profound impact on the herd.
By now, news of the big bull elephant hunted
in Zimbabwe last week has made its way around the internet. The bull is
a “tusker”—an elephant genetically predisposed to being extra big, with
extra-large tusks.
His tusks are some of the biggest taken by a hunter in recent decades, according to commenters on an online forum where the photo
of the dead animal received fulsome praise from other hunters. The
tusks weighed in at 120 pounds and 122 pounds each, according to social
media posts.
The elephant was shot in a hunting concession in the Malipati region
of Zimbabwe, between Gonarezhou National Park and South Africa’s Kruger
National Park, which is home to many large bulls.
The shooting of this elephant is drawing the ire of conservationists
and scientists alike, who say that killing such an animal has
consequences both in terms of protecting the species and in promoting
cultural heritage.
Many hunters, on the other hand, argue that the elephant was either
past his breeding age or has passed on his genes enough times that he
has made a sufficient contribution to the gene pool.
“That’s nonsense,” said Joyce Poole, a researcher who has studied
elephant reproduction for decades. “That male they killed was in his
prime, and not only was he incredibly important to the females, he was
really important to other males as a leader in male society.”
“Old and experienced individuals are crucial,” said Vicki Fishlock,
the resident scientist at Amboseli Trust for Elephants, a research and
conservation organization in Kenya. “They are so much more than ‘a
breeder’—by the time these animals reach this size, they have been parts
of social networks for five or six decades and have accumulated social
and ecological experience that younger animals learn from.”
Experts place this elephant at around 50 years old. “Prime” breeding
age is considered mid-40s to around 50, and female elephants actually
prefer to mate with older, bigger bulls such as this one, research shows.
Plus, research
shows that younger male elephants can become aggressive when older
bulls aren’t around, much in the way juvenile delinquency in our own
cultures has been attributed to the absence of fathers, said Caitlin E.
O’Connell, a professor at the at the Stanford School of Medicine and an
elephant expert.
But there are very few bigger, older male African elephants left,
Poole said. Poachers have gotten many of them, which is why there’s now a
growing trend toward poaching even young elephants with small tusks.
And that’s part of the reason hunters have been celebrating this
particular kill. Getting to take home trophy tusks of this size has
become increasingly difficult. Nowadays, hunters say they’re excited for
anything bigger than 75 pounds. And while there have been a few big
elephants hunted in Zimbabwe this year, the average tusk size that hunters can expect is closer to 40 or 50 pounds, according to one website.
Tusk size is, in part, genetic. While the bull killed last week
surely has mated many times, the genes for big tusks are already on the
decline, meaning the genetic contribution of every elephant is
important. Elephants are now evolving to have smaller tusks because poaching and hunting has removed many big-tusked elephants from the gene pool.
Protections for Cultural Icons?
Aside from the biological impacts of removing a large-tusked male
from the breeding population, conservationists and even some hunters
have raised ethical and cultural concerns.
On the hunting forum accuratereloading.com,
one commenter, identified as Mike, said, “Shooting an elephant like
that is kind of like shooting the last tasmanian devil. This elephant
will not be replaced for a long time given the terrible state of African
elephants.”
Louis Muller, the chairman of the Zimbabwe Professional Hunters and Guides Association, told The Telegraph
that big elephants could benefit from the extra protection afforded by a
tracking collar. “‘We have suggested before to all concerned parties
that each elephant area should collar a few with biggest tusks, so that
we do not shoot them...Nobody responded to our suggestion last year. We
believe this might now be taken seriously.’”
Elephants as big as the Zimbabwe bull are iconic, and
conservationists have suggested that village communities would benefit
more from the tourism money the magnificent animals could bring than
from trophy hunting fees.
Hunting “is legal, but the thing is, the ethics [are] out the
window,” Johnny Rodrigues, the head of the Zimbabwe Conservation Task
Force, told BBC World Service.
“When you see an elephant like that, which you haven’t seen for years,
you should actually put a collar on it and use it as a marketing tool
because not everywhere in the world can you find an animal like that.”
Besides, elephants are feeling creatures, and that needs to be
considered, Joyce Poole said. They’re long-lived, intelligent, and
social. They’re self-aware animals that think about the future, think
about the past, that are aware of death. This elephant had friends who
cared about him, and it will make a difference to their lives that he’s
gone.”
To companions of all ages,” added Vicki Fishlock, “the loss of these individuals makes a profound difference.”
Elephants
tusk size has shrunk by half during the past 150 years. Here, a worker
carries a tusk to auction in Mombasa, Kenya, in 1969.
Photograph by Bruce Dale, National Geographic
What We Know About the Hunt
The identity of the hunter, a German, has not been made public.
Take Aim Safaris, a company owned by Carl Knight that offers elephant
hunts in the Gonarezhou region, where the bull was shot, was originally
given credit
for the hunt. Its website—now down for “scheduled maintenance”—featured
a photo of the dead elephant. According to the website, Take Aim
Safaris charges a $20,000 trophy fee for elephant with tusks of 90
pounds or more.
The hunt was led by a well-known professional hunter named Nixon Dzingai, who did not respond to emails or calls.
What’s In a Name?
There was originally some speculation that the elephant could have been Nkombo,
a tusker from Kruger National Park, but Nkombo was seen a few days
before the hunt more than 70 miles south, and it’s improbable he could
have traveled so far so fast. Besides, people who have tracked and
photographed Nkombo say he rarely strays far.
Hunters who saw the photo of the dead bull immediately worried that
he may have had a name. When people found out the lion killed in
Zimbabwe over the summer had a name, Cecil, it ignited a media storm.
“Really hope this elephant did not had [sic] a name,” said one
commenter on the hunting forum. (Read this, and other hunters’ reactions
to the kill here). Research shows that humans are more apt to sympathize with animals that share traits with us, such as intelligence, emotion—and names.
Conservationists in the Gonarezhou area have said that this elephant
hasn’t been sighted before, so it’s possible that he’d wandered up from
Kruger .
Regardless of opinions on sports hunting, the industry needs to
restrict hunting of elephants with tusks over a certain size, said
Caitlin O’Connell, who believes hunting has an economic role in Africa.
“There need to be checks and balances. There were no checks and balances
here here. This was a fluke event that someone should have stopped. It
should have been a huge gift to the country that he...was there.”
This story was produced by National
Geographic’s Special Investigations Unit, which focuses on wildlife
crime and is made possible by a grant from the BAND Foundation.
Thursday, October 8, 2015
MAGIC 3D
Before the National Park Service, Yellowstone was guarded by the cavalry
Before the National Park Service, Yellowstone was guarded by the cavalry http://smithmag.co/WhdUNM
http://smithmag.co/WhdUNM
FROGS FACE MASS EXTINCTION
Things aren’t looking good for reptiles and amphibians lately, especially frogs. John Alroy at Macquarie University in Australia published a study last month examining recent extinctions for the two groups of animals, and the results are alarming. “About 200 frog extinctions have occurred and hundreds more [frog species] will be lost over the next century, so we are on pace to create a mass extinction,” according to the study.
“It is hard to know how many species have gone extinct so far because it is difficult to prove that something not seen recently is really gone forever,” says the paper’s summary. Alroy was inspired to conduct the study because he couldn’t find any research on the total number of species that have gone extinct. But by using what he calls a “new, highly conservative statistical method,” he was able to infer the number of extinct amphibian and reptile species across the world.
Read more: http://www.canberratimes.com.au/environment/animals/frogs-face-mass-extinction-macquarie-university-report-20151005-gk1e29.html#ixzz3o3ABi5mL
Mass extinction: The global frog population is under threat. Photo: Brian Gratwicke
Read more: http://www.canberratimes.com.au/environment/animals/frogs-face-mass-extinction-macquarie-university-report-20151005-gk1e29.html#ixzz3o3ABi5mL
Alroy chose to study reptiles and amphibians partly because “there was a large amount of global data available for these groups, and partly because of a growing concern in the scientific community over the health of frog populations, which are thought to be in a state of decline in many places,” says the Washington Post.
Alroy also looked at salamanders, snakes and lizards, but “he found that frogs seemed to be the most vulnerable to extinction—the results suggested that more than 3 percent of all frog species have disappeared, largely since the 1970s,” according to the Washington Post.
The findings are especially alarming because the research method known as a Bayesian approach is “highly conservative,” meaning that the estimated number of past and future frog extinctions could, in fact, be even higher.
“Consistent with previous results, frog losses are heavy in Latin America, which has been greatly affected by the pathogenic chytrid fungus Batrachochytrium dendrobatidis,” says the paper. “Extinction rates are now four orders-of-magnitude higher than background, and at least another 6.9 percent of all frog species may be lost within the next century, even if there is no acceleration in the growth of environmental threats.” That means that reptiles and amphibians are going extinct at 10,000 times the rate of other organisms.
“Thus, the data suggest that a runaway train of extinction is now likely to produce what would be seen as a global mass extinction on the ultimately more important landscape of geological time,” Alroy writes in the paper. It’s not surprising that frogs are especially vulnerable, though. “They’re seen as a ‘canary in the coal mine’ group because they seem to suffer large population losses more easily than other groups,” Alroy said. “What was surprising was the geographic pattern of frog extinctions.”
Many have documented the frog losses in Central America, but Alroy found large losses in places such as Brazil, Madagascar and New Guinea—“places where there are not well-documented population losses due to anything,” Alroy said. “I think there are mass extinctions happening in the tropics that are largely undocumented.”
As for what’s causing the mass extinctions, Alroy cautions against pointing the finger solely atclimate change. “There’s a tendency in the literature to focus very strongly on the potential future impacts of climate change, specifically,” Alroy said. And while climate change is likely to be an important factor in the coming years, “this paper suggests that in the absence of really severe climate change we’ve already seen the beginning of a major mass extinction.”
“I’m not saying we should stop looking at climate change,” he added. “I’m saying there should be additional focus on other causal factors like habitat destruction and invasive species in particular. So I’m hoping this paper will encourage more research of that kind.”
..............................................
Frogs face mass extinction with new research showing hundreds of species have been lost over three decades due to factors such as pollution and habitat destruction.
If extinction rates continue unabated, hundreds more frog species could be lost within the next century.
John Alroy, study author and associate professor at Macquarie University's Department of Biological Sciences, analysed international data on the decline in frog populations for his research, to be published in Proceedings of the National Academy of Sciences of the USA on Tuesday.
Dr Alroy found 200 of the world's 6355 known frog species died out in a 30-year period from the 1960s to the 1990s.
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"That's pretty bad because if you project that forward for the next couple of centuries you end up with a percentage which would resemble a mass extinction," he said.
Even if there is no increase in environmental threats, Dr Alroy's conservative estimate is that another 6.9 per cent of species will die out in the next hundred years.
"Everything is getting worse for frogs," he said.
While global warming might be contributing to the decline in frog populations, Dr Alroy said that the majority of species had been lost to due to other factors.
"The losses are coming from the introduction of invasive species, the spread of a fungus called BD (Batrachochytrium dendrobatidis), habitat destruction and, potentially, pollution," he said.
The largest loss of species has occurred in Central America and Brazil, where populations have been devastated by the BD fungus.
Dr Alroy also noted significant declines in frog species in Papua New Guinea, which could be attributed to deforestation.
Populations remain largely unaffected in Europe, the US, South East Asia and the African mainland but Dr Alroy found 11 per cent of frogs on Madagascar had become extinct.
Many of Australia's 230 frog species are under threat with data from the Department of Environment showing four have died out, including the southern gastric-brooding frog, the northern gastric-brooding frog, the Mount Glorious torrent frog and the sharp-snouted torrent frog.
"Australia is not too bad," Dr Alroy said. "Only a a handful have become extinct but there are a number which are under threat and that's a cause for concern."
Read more: http://www.canberratimes.com.au/environment/animals/frogs-face-mass-extinction-macquarie-university-report-20151005-gk1e29.html#ixzz3o3BOrZvI
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