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Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Monday, February 29, 2016

FEAR---"An unpleasant emotion caused by the belief that someone or something is dangerous, likely to cause pain or death",,,,,,,,,,,,,,,,,,,,"Fear causes a change in metabolic and organ functions and ultimately a change in behaviour, such as fleeing, hiding or freezing from perceived traumatic events",,,,,,,,,,,,,,,,,,,,,,,,It is heartening to know that THE LANDSCAPE OF FEAR PARADIGM as coined and explained by biologists John Laundre and Bill Ripple is being discussed as it relates to how forest regeneration, species diversity and optimum recognition of healthy ecosystems can be recognized by returning large carnivores to our open spaces ..................Below, our friend John Laundre expounds further on how critically important it is for trophic carnivores like Pumas and Wolves to be re-introduced to our eastern forests so as to once again make them fully functioning systems that benefit all life including our own

The lack of the landscape of fear in eastern forests

The recent article in the Washington Post by Sarah Kaplan (Dread is vanishing for the animal world. Here’s why that’s a bad thing, Morning Mix, February 24) highlighted a recently published scientific article demonstrating how fear of large predators can establish a “landscape of fear” in their prey, in this case a smaller, meso-predator, the raccoon. Because prey will be reluctant to go to areas where there is a high risk that they will be killed, fear can have profound effects on their behavior and spatial use of the landscape. The avoidance of high risk areas then cascades through to all levels of the ecosystem.

 As the originator of the ecological concept of the landscape of fear (, it is obviously satisfying to see experimental support of the model I proposed. However, beyond personal satisfaction, I find the results of this work to have tremendous implications to the whole Eastern forest ecosystem.

As the authors concluded and Ms Kaplan aptly pointed out, the lack of a landscape fear can have immense and ecologically harmful impacts across a whole ecosystem. And that is what is happening across the entire eastern forest. When white-tailed deer returned to the East in the late 20th century, they have returned to a landscape lacking the original large predators, wolves and cougars… a landscape lacking fear. As a consequence, deer have not only increased to excessive numbers but are free to roam around the landscape eating whatever they want, wherever they want, and whenever they want.

The ecological results of this uncontrolled herbivory by deer are being documented all across the East. Foresters complain deer are hindering reforestation by “vacuuming up” tree seedlings they plant. All across existing forests, the lack of survival of native tree seedling is halting the regeneration of these forests as old trees die.

 On the forest floor, the diversity of native flowering plants is decreasing, being replaced by invasive species unpalatable to deer. In particular, the ginseng industry is suffering as deer eat the emerging plants before humans can harvest them. Although not as well documented, the removal of ground cover plant species by deer is affecting the survival of ground nesting birds and may even be the cause of the decline in the New England cottontail rabbit.

More closer to us personally, excess numbers of deer give most of the eastern states the dubious honor of being the top states for deer-car collisions, resulting in thousands of injuries and an excess of 100 deaths per year. High rates of Lyme disease, requiring the association between ticks and deer can also likely be attributed to the uncontrolled deer numbers and movements across the landscape.

These and more demonstrate that the eastern ecosystems are declining under the sheer number and free movement of deer across a landscape lacking of fear. It is now accepted that to return a prey without its predator is an ecological blunder, a blunder that can only be rectified by the concurrent return of the predators, the return of the landscape of fear. This is why I and many others, in particular, the Cougar Rewilding Foundation (, have been calling for the reintroduction of cougars to the East.

 There is abundant habitat for cougars across much of the East and contrary to popular myths, cougars are not particularly dangerous. The now famous cougar, P22 in Southern California ( has amply demonstrated that cougars can easily live harmoniously within heavily populated areas.

The return of cougars would likely reduce the excessive number of deer somewhat but more importantly, they would keep the remaining deer in their ecological role by fear and prevent them from the massive destruction they are currently causing. Cougars would establish a landscape of fear that would create refuges in high risk areas for favored plant species of deer, maintaining forest diversity and allowing regeneration of the forest to occur.

 As cougars are most effective along forest edges in capturing their prey, deer might be more reluctant to use forest edges along highways, reducing deer-car collisions and saving lives.

These and many more safety and ecological reasons clearly justify the return of cougars to the East. They would be relatively good wildlife neighbors and provide valuable ecological benefits and services that would help restore the ecological health of eastern forests. This article reported in the Washington Post demonstrates that the science is solidly behind the need for cougars in the East. What is lacking is the social will to do the ecologically right thing, return cougars to the east where they belong.

Dr. John W. Laundré
Large predator ecologist/Assistant Director
James San Jacinto Natural Reserve
University of California Riverside
Riverside California

Sunday, February 28, 2016

The 12th consecutive year of studying Black Bears in northern Michigan by the Dept of Natural Resources is revealing that "“Black bears are doing very well"..............."Litter sizes seem to be a little bigger than they were 20 to 25 years ago and the fitness of the bears being trapped for study is robust...................Approximately 15,000 - 19,000 black bears (including cubs) roam the hardwood and conifer forests of northern Michigan................ About 90 percent of the bear live in the Upper Peninsula, while the remaining ten percent are mainly found in the northern Lower Peninsula...........While it is becoming increasingly common to see bear in the southern half of the Lower Peninsula, there is still no breeding population in the southern half of the state

Roscommon Forest Site of DNR Black Bear Project

Posted: Feb 23, 2016 3:16 PM PST

A very special project takes DNR crews deep into the forests of Northern Michigan in search of one of the state's largest carnivores -- black bears.
The DNR looks for hibernating bears to replace tracking collars and learn more about how they are doing in Northern Michigan this season.
It's all a part of the 12th Surrogate Sow Bear Monitoring Program.
Today, they visited Roscommon County to continue their bear tagging project.
"This is the twelfth consecutive year that we've been out, collaring black bears," says Mark Boersen, DNR wildlife biologist.
Searching for a large, furry, hibernating predator is not easy ...
It takes an air crew, then a ground crew, to help track them down.
"We have our pilot and another wildlife personnel check to get a general location and narrow it down for me so I know where to start and then we do ground-scouting, locate the den, GPS the den," Boersen says. “Permissions have to be sought from landowners when we are working on private property. We never trespass on private property. We also invite them along, too, if they choose to come along.”
But a bear's den can change locations depending on many factors, the DNR says.
This adds an additional hurdle for crews while they begin ground-tracking.
"Sometimes, they just simply find a location right out in the middle of the open," says Katie Keen, DNR wildlife technician. "It's hard to believe. Other times, they can be tucked in a little bit, maybe next to a root mass or a tree."
A VHF radio helps pinpoint the den of a large mother bear and her two cubs, the goal of this morning's search.

“We have a small radio-receiver box and a hand-held antenna that we can track her collar with," Boersen says. “It works very simply by you can point it in the direction of the collar and, if you are pointing at the collar, it gets louder.”
Keen says the female bear was first collared by Boersen and his team in 2013.
She says a lot can change in as much as a year's time.
“When we were here a year ago, she actually had newborn cubs and she had four, so when we are going to go in today, they will be yearlings, so they are a year older at this point," Keen said prior to tracking the bear. "They can be 50 to 70 pounds of fur, nails and teeth, but we’ll go in there and see how many she still has.”
With the radio's help, it didn't take long.
We waited behind while the group sedated the 234-lbs. mom.
"It really went almost textbook," Boersen says. "We were able to get the female sedated very quickly. [Three years ago,] we scouted her and found her actually in a ditch, covered in snow. It was far less elaborate than the den we saw today.”
The 45-minute process is that long for a good reason.
They check her oxygen, her weight, her blood, make sure she's top-notch health during the entire process.
“We look over her general health, we monitor her vitals while we are working on her, make sure she’s doing well," Boersen says. "Administer a variety of drugs, antibiotics. We keep her on oxygen throughout most of the work.”
Also, two yearlings are out here, running around but they will come back, according to the DNR.
They say silence is of the essence to make sure this job is done right.
"When all is said and done, she won't remember anything that happened to her," Boersen says.
In just around 45 minutes, mother is headed back to sleep for the winter.
With a fresh collar and important data learned...
"We can see how far they move, how many cubs they have, what kind of general health they are," Boersen says. "It's all very useful in assessing the overall population health."
Boersen says there are three main objectives to the Surrogate Sow Bear Monitoring Program.
“We keep a small number of females collared so we can use them as surrogate mothers if the DNR should come into possession of orphaned cubs," Boersen says. "Secondly, we use the reproductive data just to keep tabs on the black bear population. And finally, we use the project as a training tool so we can train other staff who maybe aren’t as familiar in handling techniques of black bears.”

While it's not the main objective, getting crews closer to black bears like the mother bear in Roscommon County helps future bear encounters.
“The training for our staff is very important up in Northern Michigan," Keen says. "We always have wild animals that can interact with kind of an urban or human interface, so this is great on-the-job training for our staff.”
Keen also says preparing for orphaned cubs also is easier by keeping tabs on bears in the wild.
“If we have an orphaned cub in the summertime, we will have female bear in the Northern Lower with that same age young," Keen says. "We can place that orphan cub with her and she will take in new cubs.”
As for the overall look at Northern Michigan's black bear population, Boersen says things look promising.
“Black bears in Northern Michigan are doing very well," Boersen says. "In many areas, we are seeing population expansion. We are seeing litter sizes that seem to be a little bigger than they were, say, 20 to 25 years ago and we are seeing, large healthy bears when we handle these bears.”

Saturday, February 27, 2016

"In North America the prevalence of Lyme disease has risen following forest fragmentation"..............."The ensuing reduction in mammal diversity has enabled the white-footed mouse – a prime carrier of the pathogen – to proliferate over new territories due to having fewer predators and competitors"............... "Ticks feeding on the mice can pass the disease to humans".............. "A similar situation exists in much of Asia with tick-borne encephalitis"................ "It's clear that the expansion and emergence of infectious diseases due to global deforestation is of pressing concern"................. "Scientists agree on the urgency of the case and acknowledge that the issue is not sufficiently understood"................."The value of intact forest to protect public health is certainly underappreciated"............... "Links between ecosystem changes and disease-spread are currently unrecognized"............"This is insidious to the extent that by the time we have an epidemic we often don't look far back enough to see the causal factors, we just look at the proximal issues such as changes in mosquito-control or human population migration".......... "In many cases, it really goes back to the ecosystems and what we're doing to them – new risk factors that may cause the emergence or resurgence in diseases"............. "Many of the irreversible changes we're doing to our landscape could lead to serious public-health threats"..................... "We must manage land-use more conscientiously and in a way that minimizes the unintended consequences"

Deforestation could fuel deadly spread of malaria, yellow fever and Lyme disease

David Hawkins
17th November, 2010

The economic and climate-related impacts of forest destruction are well known, but continued logging could unleash devastating new pandemics and spread fatal diseases into the human population, scientists tell the Ecologist

The costs of deforestation in terms of climate change, biodiversity and economics are well known. Rainforests are also reservoirs for possible drugs, many of which have not yet been explored. But alarming new scientific research is presenting another compelling case for the urgent need to stop destruction of the world's forests.
In a series of exclusive interviews, scientists have told the Ecologist that if we don't keep remaining forests intact there is a danger that some of the planet's most life-threatening diseases could spread on a dangerous and unmanageable scale. The experts also warn that there is a serious risk of unleashing pandemics of new viruses into the world's human population.

Continued deforestation has the potential to unleash
 devastating pandemics into
 human populations, scientists claim
Ravinder Sehgal, associate professor of biology at San Francisco State University, specialises in studying the effects of deforestation on African rainforest birds by mapping and modelling their diseases and blood parasites. But his research has huge potential relevance to human health.
'Non-migratory birds are a more natural system than humans, who move around a lot, so in looking at them we can determine how ecology affects the spread of disease a bit more easily,' he says. His work in Africa on species including the olive sunbird has revealed the effects of deforestation: 'We found different types of malaria in the same species of bird in deforested versus intact areas.'
The implications of this are clear, according to Sehgal: deforestation upsets the ecological balance, allowing diseases to move in unpredictable ways.
Spreading malaria
Africa has already witnessed an expansion of malaria's range. Dr Steve Lindsay, professor of public health entomology at the London School of Hygiene & Tropical Medicine, has nearly three decades of experience looking at vector-borne diseases throughout African and Asia. 
'Deforestation raises ground temperature, increasing the rate at which mosquitoes develop into adults, frequency of blood feeding, the rate at which parasites are acquired, and the development of the parasite within mosquitoes,' he says. These increased surface temperatures due to forest clearing have allowed malaria parasites to spread their range to higher elevations, with the disease now commonly encountered in the previously malaria-free highlands of East Africa. 'For every 1 per cent of reduction in forest cover there is an 8 per cent rise in malaria mosquito population.'
With disease, however, nothing is straightforward. Lindsay acknowledges that in much of southeast Asia malaria is passed on by a forest-dwelling mosquito, so deforestation there could actually reduce cases


In the Amazon, the primary vector for malaria is a species of mosquito named Anopheles darlingi. Recorded at very low levels a few decades ago, and even absent from many areas, this mosquito has made a massive comeback in recent years, according to scientists. Jonathan Patz, professor of global environmental health at the University of Madison, Wisconsin, is a widely published member of the Intergovernmental Panel on Climate Change, with a special interest in ecology, land-use change and human health. He sees this upsurge as a direct result of deforestation: 'We don't yet know the mechanism, but the partially sunlit pools in deforested areas yield more mosquito larvae.' Logging and clearance are seen as creating an ideal habitat for malaria incubation.

Things don't necessarily get better over time. Patz says that 'the mosaic effect' of secondary, regrowth forest and abandoned land can be 'even worse' for malaria than recently deforested locations. Additionally, once malaria has been allowed to arise it is difficult to contain. 'Places that historically had been logged had a much higher incidence of malaria among people,' he says. When an area has been cleared of forest it can remain contagious for a long time.
Logging dangers
Yellow fever is another deadly disease whose complex ecology can be sent spiralling by deforestation. Usually, it is passed from monkey to monkey by mosquitoes in the high canopy. Logging can bring the monkeys closer to human habitation, and foresters into direct contact with the disease. Infected individuals from these fringe populations may then visit cities where the pathogens are picked up by the urban mosquito, Aedes aegypti, which also carries dengue fever. In this way new outbreaks can occur.

Along with deforestation, climate change and population movement, land-use change is capable of bringing diseases to new areas. In recent times the disease leishmaniasis (vectored by sandflies) has shifted its reservoir from wild animals to domestic dogs. Rice paddies in the Amazon have led to an increase in rodents, and so greater incidence of leptospirosis (Weil's disease). Professor Patz notes that large numbers of A. darlingi larvae are found in commercial fishponds. He claims that foregrounding strategies such as farming fish species that feed on mosquito larvae could be crucial methods of combating disease in these high-risk zones.

Lafcadio Cortesi, forests campaign director for Rainforest Action Network, recognises all this as a serious threat, and states that 'in terms of human productivity and quality of life, malaria is already having a huge effect'. This is an issue underexploited by environmental campaigners so far, and one that may become increasingly central. He brings in an ethical angle: 'The few elites mostly benefiting from logging activity aren't [yet] affected by the diseases they're helping to spread.'

New science of this type will be another powerful ally for those fighting for protection of the world's forests. We've heard of 'avoided deforestation', when forests are preserved on economic grounds, but what about the unreckonable savings of potentially 'avoided disease' made by keeping them intact?

HIV viruses
Regarding these multifarious costs, Matthew Lebreton, director of the Central Africa Ecology Program for the Global Viral Forecasting Initiative (GVFI), wonders of HIV/AIDS: 'If we were doing the same work we are today in these African villages, 50, 80 or 100 years ago, what could have been done to prevent the disease or reduce its impact?' He warns: 'We are seeing new viruses in the same family as HIV crossing over into populations now.'

Headed by the dynamic scientist Nathan Wolfe, GVFI places itself 'at the interface of potentially dangerous diseases and human populations'. Monitoring diseases in places such as forest edges and regularly testing the blood of people there, while looking out for new illnesses, Matthew Lebreton and his team have a wealth of on-the-ground experience. Populations in these areas have a higher risk of contracting zoonoses (diseases that can pass from animals to humans – swine flu, avian flu and SARS being famous examples) that could then escalate. This kind of cutting-edge research is crucial for future health worldwide.

'The only way to really prevent pandemics is through education, addressing how to change behaviour and avoid risks,' Lebreton explains. Putting a name and a place to a virus – where it was discovered and in what animal or person – helps people in rural communities visualise these pathogens as real threats. 'Globally, vital to the process of prevention will be finding out new ways of making very targeted interventions related to particular species or particular behaviours to stop transmission,' he says. He cites ebola outbreaks after people have retrieved dead animals from the forest, or blood contact following hunting, as examples.

Pointing out something else easily forgotten, Lebreton says: 'Animals are just as much victims of disease as we are, and finding starting points of those viruses is extremely important. It's really significant for conservation to figure out what risks those animals have in the long term.'
Chimpanzees and (already-endangered) gorillas have suffered tremendously from ebola in Central Africa. GVFI is keen to dovetail the interests of human health with conservation. Bushmeat-hunting is already illegal in many places, and when people are aware of the risks of diseases such as ebola they are less likely to target primates.

Lebreton adds: 'There is an enormous number of viruses in wild animals already that we know very little about.' Understanding this diversity is a significant part of forest ecology, as deforestation can have complex and subtle effects. 'There are a few species, such as bats, that tend to be more susceptible to disease when their habitat it threatened or when they're put under stress. Then they are more likely to become infectious,' he says. At the same time, forest fragmentation can cause population bottlenecks, with the resulting inbreeding making animals weaker and in more danger of contracting and carrying diseases.

There is a human correlation to this, too, as Ravinder Sehgal suggests: 'People living with HIV/AIDS in these deforested areas might be more likely to get some of these new pathogens. It is tremendously complicated what's going to happen in Africa with the interactions between different diseases and deforestation. I imagine that immuno-compromised populations are breeding-grounds for new pathogens, because if a virus gets into a person with HIV/AIDS it's more likely and more able to mutate and survive in that person. So a person with HIV/AIDS is like a mixing ground, where these pathogens can potentially evolve and become more pathogenic and spread to other people.'

Sehgal also points to new research into something known as the 'dilution effect': 'Species-rich communities can potentially snuff out transmission of pathogens, such as parasites, by "wasted" transmissions to hosts who are unable to pass the parasite on to the next life stage.' This is another way in which biodiversity offers us a hidden and vital service. The enormous harmful effect of deforestation only hastens the demise of such natural systems, increasing the chance of diseases leaking out.
Lack of understanding
It might sound as though these threats are particular to the tropics, but deforestation in temperate zones can have serious consequences as well. In North America the prevalence of Lyme disease has risen following forest fragmentation. The ensuing reduction in mammal diversity has enabled the white-footed mouse – a prime carrier of the pathogen – to proliferate over new territories due to having fewer predators and competitors. Ticks feeding on the mice can pass the disease to humans. A similar situation exists in much of Asia with tick-borne encephalitis.
It's clear that the expansion and emergence of infectious diseases due to global deforestation is of pressing concern. Scientists agree on the urgency of the case and acknowledge that the issue is not" sufficiently understood.

Patz complains: 'These studies have not been well funded; the value of intact forest to protect public health is certainly underappreciated, and policymakers need to take this into account. Links between ecosystem changes and disease-spread are currently unrecognised, and this is insidious to the extent that by the time we have an epidemic we often don't look far back enough to see the causal factors, we just look at the proximal issues such as changes in mosquito-control or human population migration. In many cases it really goes back to the ecosystems and what we're doing to them – new risk factors that may cause the emergence or resurgence in diseases. Many of the irreversible changes we're doing to our landscape could lead to serious public-health threats. We must manage land-use more conscientiously and in a way that minimises the unintended consequences.'

In North Amrica during the 16th, 17th, 18th, 19th and 20th centruries what diseases manifested themselves in humans as we cut down the forests and Prairies............."(When we look at) The Roman Empire (which) once stretched from Scotland to Africa and lasted for more than 400 years, no one (seems to) knows exactly why (it) collapsed"..........."(One key) contributing factor may have been malaria"............ "A mass grave of babies from that era, excavated in the 1990s, found, through DNA analysis, that many of them had died from malaria".......... "Some researchers speculate that the malaria outbreak may have been exacerbated by deforestation in Rome’s surrounding Tiber River Valley to supply timber to the growing city"............."(It is more critical than ever) to recognize and understand (the) connections(between deforestation and human disease) and (we must) teach people that keeping nature intact has protective effects".............. "And where people do cut down forests or build roads, numerous steps can be taken to lessen the chance of mosquito-borne disease outbreaks — education campaigns, more clinics, health training, and medical monitoring"

23 FEB 2016: REPORT

How Forest Loss Is Leading
To a Rise in Human Disease

A growing body of scientific evidence shows that the felling of tropical forests creates optimal conditions for the spread of mosquito-borne scourges, including malaria and dengue. Primates and other animals are also spreading disease from cleared forests to people.

by jim robbins

In Borneo, an island shared by Indonesia and Malaysia, some of the world’s oldest tropical forests are being cut down and replaced with oil palm plantations at a breakneck pace. Wiping forests high in biodiversity off the land for monoculture plantations causes numerous environmental problems, from the destruction of wildlife habitat to the rapid release of stored carbon, which contributes to global warming. 

But deforestation is having another worrisome effect: an increase in the spread of life-threatening diseases such as malaria and dengue fever. For a host of ecological reasons, the loss of forest can act as an incubator for insect-borne and other infectious diseases that afflict humans. The most recent example came to light this month in the Journal of Emerging Infectious Diseases, with researchers documenting a steep rise in human malaria cases in a region of Malaysian Borneo undergoing rapid deforestation. 

An area of forest in Indonesia that was cleared to make way for an oil palm plantation.

This form of the disease was once found mainly in primates called macaques, and scientists from the London School of Tropical Medicine and Hygiene wondered why there was a sudden spike in human cases. Studying satellite maps of where forest was being cut down and where it was left standing, the researchers compared the patchwork to the locations of recent malaria outbreaks. They realized the primates were concentrating in the remaining fragments of forest habitat, possibly increasing disease transmission among their own populations. Then, as humans worked on the new palm plantations, near the recently created forest edges, mosquitoes that thrived in this new habitat carried the disease from macaques to people. 

Such phenomena are not uncommon. "In years when there is a lot of land clearance you get a spike in leptospirosis [a potentially fatal bacterial disease] cases, and in malaria and dengue," says Peter Daszak, the president of Ecohealth Alliance, which is part of a global effort to understand and ameliorate these dynamics. "Deforestation creates ideal habitat for some diseases." 

The Borneo malaria study is the latest piece of a growing body of scientific evidence showing how cutting down large swaths of forests is a major factor in a serious human health problem — the outbreak of some of the world’s most serious infectious diseases that emerge from wildlife and insects in forests. Some 60 percent of the diseases that affect people spend part of their life cycle in wild and domestic animals. 

The research work is urgent — land development is rapidly taking place across regions with high biodiversity, and the greater the number of species, the greater the number of diseases, scientists say. They are deeply concerned that the next global pandemic could come out of the forest and spread quickly around the world, as was the case with SARS and Ebola, which both emerged from wild animals. 

Mosquitoes are not the only carriers of pathogens from the wild to humans. Bats, primates, and even snails can carry disease, and transmission dynamics change for all of these species following forest clearing, often creating a much greater threat to people. 

Throughout human history pathogens have emerged from forests. The Zika virus, for example, which is believed to be causing microencephaly, or smaller than normal heads, in newborns in Latin America, emerged from the Zika forest of Uganda in the 1940s. 
The risk of disease outbreaks can be greatly magnified after forests are cleared for agriculture and roads.
Dengue, Chikungunya, yellow fever, and some other mosquito-borne pathogens likely also came out of the forests of Africa. 

Forests contain numerous pathogens that have been passed back and forth between mosquitoes and mammals for ages. Because they evolved together, these viruses often cause few or no symptoms in their hosts, providing “a protective effect from a homegrown infection,” says Richard Pollack of the T.H. Chan School Public Health at Harvard. But humans often have no such protection. 

What research is demonstrating is that because of a complex chain of ecological changes, the risk of disease outbreaks, especially those carried by some mosquitoes, can be greatly magnified after forests are cleared for agriculture and roads. 

A flood of sunlight pouring onto the once-shady forest floor, for example, increases water temperatures, which can aid mosquito breeding, explained Amy Vittor, an assistant professor of medicine at the University of Florida. She is an expert in the ecology of deforestation and malaria, which is where this dynamic is best understood. 

Deforestation creates other conditions conducive to mosquito breeding. Leaves that once made streams and ponds high in tannins disappear, which lowers the acidity and makes the water more turbid, both of which favor the breeding of some species of mosquito over others. Flowing water is dammed up, deliberately and inadvertently, and pools. Because it is no longer taken up and transpired by trees, the water table rises closer to the forest floor, which can create more swampy areas. 

As agriculture replaces forest, "re-growth of low lying vegetation provides a much more suitable environment" for the mosquitoes that carry the malaria parasite, Vittor says. 

Ulet Ifansasti/Getty Images
A man sleeps inside a mosquito net in his home in West Papua, Indonesia.

The link between deforestation and increases in malaria has been known for some time, but research in the last two decades has filled in many of the details. Much of the work has been done in Peru, where in one region in the 1990s cases of malaria went from 600 per year to 120,000, just after a road was built into virgin forest and people began clearing land for farms. 

The cascade of human-induced ecological changes dramatically reduces mosquito diversity. "The species that survive and become dominant, for reasons that are not well understood, almost always transmit malaria better than the species that had been most abundant in the intact forests," write Eric Chivian and Aaron Bernstein, public health experts at Harvard Medical School, in their book How Our Health Depends on Biodiversity. "This has been observed essentially everywhere malaria occurs." 

Mosquitoes can adapt fairly quickly to environmental change. In response to a push to use bed nets to prevent nighttime bites in malaria-prone regions of the world, for example, researchers are seeing a change in the time of day mosquitoes bite — many now target their human quarry in the hours before bed. 

A study by Vittor and others found that one malaria-carrying mosquito species, Anopheles darlingi, in a deforested area in Peru was radically different than its cousins in intact forests; the Anopheles darlingi in deforested areas bit 278 times more frequently than in an intact forest, according to a study published in the American Journal of Tropical Medicine and Hygiene in 2006. 

"In the forest, we found almost no breeding whatsoever, and no biting by the adult mosquitoes," Vittor said. That’s probably because the ecology of the deforested landscape — short vegetation and deep water — favored their breeding, and they need human blood to grow their eggs. 

The types of mosquitoes that do well in this radically altered ecosystem are more "vector competent," which means their systems are particularly good at manufacturing a lot of the pathogen that causes malaria. A study in Brazil, published in the Journal of Emerging Infectious Diseases in 2010, found that clearing four percent of the forest resulted in a nearly 50-percent increase in human malaria cases. 

The ecology of the viruses in deforested areas is different. As forests are cut down, numerous new boundaries, or edges, are created between deforested areas and forest. A mosquito called Aedes africanus, a host of the yellow fever and Chikungaya viruses, often lives in this edge habitat and bites people working or living nearby. Other primates, which are also reservoirs for the pathogens, gather in the borders of these different ecosystems, providing an ongoing source of virus for the insects. 

Insects are not the only way that deforestation can exacerbate infectious diseases. For some unknown reason, the species of snails that can better adapt to warm open areas that occur after a forest is cut down are better hosts for parasites called flatworms, some of which cause schistosomiasis, a disease which damages human organs. 

Scientists are concerned that these outbreaks exacerbated by human alteration of landscapes could cause the next pandemic. The Roman Empire once stretched from Scotland to Africa and lasted for more than 400 years. No one knows exactly why the empire collapsed, but one contributing factor may have been malaria. A mass grave of babies from that era, excavated in the 1990s, found, through DNA analysis, that many of them had died from malaria, according to a study published in 2001 in the journal Ancient Biomolecules. Some researchers speculate that the malaria outbreak may have been exacerbated by deforestation in Rome’s surrounding Tiber River Valley to supply timber to the growing city. 

Once a disease has left a forested region, it can travel in human beings, crossing the world in a matter of hours by airplane before the person even shows symptoms. How well it does in its new homes depends on several factors. 
One piece of the puzzle is to know what pathogens might come out of the forest in the future.
Once Zika traveled to Brazil from Africa, for example, it flourished because Aedes aegyptimosquitoes hang out around people and love to lay their eggs in small containers of water. Many people in Brazil's large slums store water in buckets, and standing water also collects in tarps, old tires, and trash. 

A key question about the Zika virus is whether it will enter the primate populations in South America, which means it might become a permanent resident and an ongoing source of infection. "Is it going to set up shop there?" asks Vittor. "We don't know." 

Mosquitoes aren't the only creatures that bring fever out of the forest. Angolan free-tailed bats were believed to harbor the Ebola virus that broke out and killed more than 11,000 people last year. And AIDS, which has killed more than 25 million people worldwide, came from people eating bush meat, likely chimpanzees. 

A wild card in this disease scenario is the rapidly changing climate. If spring comes early, mosquitoes hatch earlier and summer populations are larger. In Southeast Asia, the spike in temperatures during El Niño weather cycles correlates with dengue fever outbreaks, because the warmer weather allows mosquitoes to breed faster and expand the population, which spreads the virus further, according to a study last year in the Proceedings of the National Academy of Sciences

Part of the solution is to recognize and understand these connections and teach people that keeping nature intact has protective effects. And where people do cut down forests or build roads, numerous steps can be taken to lessen the chance of mosquito-borne disease outbreaks — education campaigns, more clinics, health training, and medical monitoring. 

Another piece of the puzzle is to know what pathogens the world might be up against in the future as they come out of the forest. Ecohealth Alliance is cataloging wildlife-borne viruses in wild places where there is new encroachment into undisturbed nature and health care is poor or non-existent. The goal is to better understand how these viruses might spread and to potentially develop vaccines. 

"If we could deal with the trade in wildlife and deforestation we wouldn't need to stop an outbreak," like Zika or Ebola, said Daszak, the organization’s president. "We would have already dealt with it." 


Friday, February 26, 2016

"Moose, Wolves and Coyotes have lived together in complex predator-prey relationships for thousands of years".............. "The ministry itself notes, “predation rates on moose by wolves tend to increase in tandem with moose numbers"............ "This naturally regulates the density of the moose population and is ultimately beneficial to moose and the ecosystems they rely on"..................So why then is the Ontario Ministry of Natural Resources seeking to allow Wolves and Coyotes to be killed adjacent to Algonquin Park when so much scientific research showed it so important to ban this very hunting paradigm so as to allow the Eastern Wolf population to remain stable ?.................Politics not science at play.......Rather than acknowledge that warming temperatures and land use alteration is adversely impacting Moose populations, easier for "those in charge" to say, "LOOK, we are doing something, We kill the Wolves that eat the Moose".........."Aren't we great?"----NOT!

Ontario should stop scapegoating wolves

A government plan to weaken regulations for hunting wolves and coyotes would do little for the moose populations it’s meant to protect

By all accounts, eastern wolves (one of which is pictured here) and coyotes are difficult if not impossible to distinguish in the field.
By all accounts, eastern wolves (one of which is pictured here) and coyotes are difficult if not impossible to distinguish in the field.
A canine predator that travels in packs in remote areas of North America is called a wolf. Most people know this, yet by all accounts the Ontario Ministry of Natural Resources and Forestry (MNRF) seems to think it’s a goat — a scapegoat.
A plan to weaken regulations for hunting wolves and coyotes in Northern Ontario treats these predators as scapegoats, with the MNRF claiming the changes will help reduce declines in the moose population. Yet moose, wolves and coyotes have lived together in complex predator-prey relationships for thousands of years. The ministry itself notes, “Predation rates on moose by wolves tend to increase in tandem with moose numbers. This naturally regulates the density of the moose population and is ultimately beneficial to moose and the ecosystems they rely on.”
Wolves and other predators occupy an important niche in nature. Science is clear that our zest for killing such animals has resulted in significant unintended consequences and ecosystem damage. For example, removing predators can cause deer populations to increase, leading to changes in natural vegetation patterns and increased disease transmission.
A recent report by the Raincoast Conservation Foundation describes humans as “super-predators” and cautions that “although grizzlies, wolves, and cougars occasionally kill one another, it’s rare. They have not evolved as prey. More enlightened wildlife management would recognize that this reality can make carnivore hunting risky business.”
The MNRF claims the new proposal will have neutral results, yet it may well harm a species at risk, the eastern wolf. The proposed changes would apply to an area abutting Algonquin Park and adjacent townships where, to protect the eastern wolf, hunting wolves and coyotes is not permitted. By all accounts, eastern wolves and coyotes are difficult if not impossible to distinguish in the field. In effect, it would be open season on eastern wolves when they venture outside the protected zone.
Most appalling is the fact that scientists, including scientists on the ministry’s own team, agree that wolf and coyote control is not a long-term solution to address declines in prey populations.
MNRF background information states that removing just a few wolves from each pack will not decrease overall predation on moose and that only wiping out wolf packs in their entirety will achieve this. (Pack eradication is most often done by aerial killing or poisoning — thankfully these options aren’t on the table.)
There are many uncertainties around the causes of recent moose declines. Climate change might be playing a role, as might disease (often exacerbated by climate change). One thing is clear, though: hunting by humans is having the most significant impact on moose populations, with ever more moose being killed as hunting-related technology improves.
Citizens throughout Ontario are left wondering what is going on. Why is a ministry responsible for protecting Ontario’s rich biodiversity putting wildlife at risk? Why is a province that advocates tolerance and diversity fanning the age-old flames of intolerance against predators, and advancing harm to the native biodiversity of Ontario?
This regulation has not yet been passed. There’s still time for the province to abandon the proposal and base its policy and approaches to wildlife management on science. If the MNRF wants to please hunters by making it easier for them to kill predators, with less oversight, it should be clear that this is the motivation for the proposed regulation. To suggest that it is to help moose populations is simply senseless.
Rachel Plotkin is the Ontario Science Projects Manager at the David Suzuki Foundation. Anne Bell is the Director of Conservation and Education at Ontario Nature.