Antarctic Ozone Layer is Healing

Scientists at MIT and elsewhere have identified the "first fingerprints of healing" of the Antarctic ozone layer.

The team found that the September ozone hole has shrunk by more than 4 million square kilometers -- about half the area of the contiguous United States -- since 2000, when ozone depletion was at its peak. The team also showed for the first time that this recovery has slowed somewhat at times, due to the effects of volcanic eruptions from year to year. Overall, however, the ozone hole appears to be on a healing path.

The ozone hole was first discovered using ground-based data that began in the 1950s. Around the mid-1980s, scientists from the British Antarctic survey noticed that the October total ozone was dropping. From then on, scientists worldwide typically tracked ozone depletion using October measurements of Antarctic ozone.

Ozone is sensitive not just to chlorine, but also to temperature and sunlight. Chlorine eats away at ozone, but only if light is present and if the atmosphere is cold enough to create polar stratospheric clouds on which chlorine chemistry can occur -- a relationship that Solomon was first to characterize in 1986. Measurements have shown that ozone depletion starts each year in late August, as Antarctica emerges from its dark winter, and the hole is fully formed by early October.

The researchers tracked the yearly opening of the Antarctic ozone hole in the month of September, from 2000 to 2015. They analyzed ozone measurements taken from weather balloons and satellites, as well as satellite measurements of sulfur dioxide emitted by volcanoes, which can also enhance ozone depletion. And, they tracked meteorological changes, such as temperature and wind, which can shift the ozone hole back and forth.

They then compared their yearly September ozone measurements with model simulations that predict ozone levels based on the amount of chlorine that scientists have estimated to be present in the atmosphere from year to year. The researchers found that the ozone hole has declined compared to its peak size in 2000, shrinking by more than 4 million square kilometers by 2015. They further found that this decline matched the model's predictions, and that more than half the shrinkage was due solely to the reduction in atmospheric chlorine.

Stray bear trapped near Kalakkad

Even as forest personnel are in search of a stray bear that was spotted near Moolaikkaraipatti in the district last Saturday, a male sloth bear that was creating panic among farmers after it strayed into the farmlands close to the Western Ghats near Kalakkad was caged in the early hours on Thursday.

The animal, which reportedly sustained injuries in a bid to escape from the cage, was released in the Sengaltheri area of Kalakkad Division of Kalakkad–Mundanthurai Tiger Reserve by noon.

The bear, reportedly from the Western Ghats, had entered the farm in search of food and water a couple of weeks ago and remained in the orchards close to Kalakkad. On noticing the movement of the animal, a farmer, Ramesh of Pillaikulam, filed a complaint with forest officials.

After securing permission from the field director, KMTR, A. Venkatesh, the officials placed a cage in the farm. The bear was caged around 3 a.m. at Pillaikulam.

The three-year-old animal had a bleeding injury on its snout and thighs, which it might have sustained while trying to escape from the steel enclosure.

A villager alleged that the forest personnel took it to the Sengaltheri area to free it without treating it.

However, forest authorities said an antiseptic cream was applied on the injury though the bear was aggressive.

The animal apparently sustained injuries on its snout and thighs while trying to escape from the enclosure.

Taken from The Hindu

Kolkata: Discovery of predator fish that resembles an alligator concerns experts

Experts are concerned about the discovery of a predatory fish that can grow up to eight feet from Subhas Sarovar in Kolkata’s eastern fringe of Beliaghata as it can destroy local ecosystem and biodiversity.

A local angler, Shibu Mondol, caught a 3.5-feet long Alligator Gar – a fish that resembles an alligator with long sharp teeth and equally predatory instincts and sometimes known to attack humans – two months ago.

Biodiversity experts, ecologists and anglers say the fish could kill almost every other fish in the lake. The prehistoric relatives of this mega fish inhabited many parts of the world, but today gars live only in North and Central America. Of the seven known species, the Alligator Gar is the largest.

 “It is a highly carnivorous fish. It not only kills other fishes but there are reports of it attacking humans too. The fish’s egg is also poisonous. It has no natural enemies and hence can become invasive in no time destroying the local ecosystem and biodiversity,” Mathe Rajeev Mathew, expert member of the National Biodiversity Authority and the Telangana State Biodiversity Board, said.

Alligator Gar has already become a nuisance in Telangana and Andhra Pradesh and reports of the fish spreading fast and becoming invasive in water bodies of Tamil Nadu are also pouring in. In 2015, an Alligator Gar was caught from a well in Dadar in Mumbai.

A group of experts has been called in to tackle the menace.

“This is the first time that this species has been caught in the city. We would like to send a team and collect the specimen. We would also try to explore the lake to check if their population has proliferated and how big is the threat,” KC Gopi, a fish expert of the Zoological Survey of India, said.

Experts say they are usually smuggled into the country to be reared in aquariums. But when the fish starts gaining size and kills other fish, owners often release them in the local water bodies.

“We have had a similar experience with another aquarium fish called the Crocodile fish while working in East Kolkata Wetlands. They are bought by aquarium keepers and then released into wild when they grow big. Crocodile fish are now found in almost every pond and lake in Kolkata and are destroying the local biodiversity,” Dipayan Dey, who heads the city based NGO South Asian Forum for Environment, said.

Mondol – the person who caught the fish - gave a scary account of how he caught the fish as it tried to attack him and snap his finger. Mondol is a member of the West Bengal Angler’s Association and fishes regularly in Subhas Sarovar.

“Unlike a Rohu or Katla fish, which usually tries to drag the rope deep into the pond after it is hooked, this fish was lying idle in the water like a tortoise. When I started pulling it out of the water, I was shocked to see the alligator-like snout. I screamed and local residents soon rushed to the spot. The fish after being pulled out not only made a dart to bite me but also killed a Katla fish which I caught earlier,” Mondol said.

The Alligator Gar that Mondol caught weighed more than five kilos.

One of Mondol’s friends killed the fish and ate its meat that tasted sour. Mondol, however, managed to retain the skin and head and is drying to preserve it.

“We couldn’t cut the fish with a knife. It was so hard that it had to be hacked with an axe,” Mondol said.

Severe water stress likely in Asia by 2050

Economic and population growth on top of climate change could lead to serious water shortages across a broad swath of Asia by the year 2050, a newly published study has found. The study deploys detailed modeling to produce what the researchers believe is a full range of scenarios involving water availability and use in the future.

 

Source: MIT

Antarctic Birds can Recognize Individual Humans

Brown skuas in Antarctica can discriminate individual people, even though they normally do not see many people around. Scientists studied brown skuas living in Antarctica.

We have heard of crows, mockingbirds and magpies recognizing individual people. These birds live among people, so it may be natural that they learn to differentiate people. But what about the animals that live in remote areas? Can anyone one of them can do the same?

Scientists in South Korea studied brown skuas living in Antarctica and reported that these birds too recognize people who had previously accessed against the skuas living in Antarctica and reported that these birds too recognize people who had previously accused the nests to measure their eggs and nestlings. 

The research team performed a series of experiments. The researchers checked the nests once a week to monitor the breeding status and the skuas attacked at closer distances with repeated visits of the researchers. to test if the birds specifically distinguish the researchers who visited the nests from those who did not, a pair of humans consisting of nest intruder and neutral human approached to the nests and walked towards the opposite directions. All seven skua pairs followed and tried to attack the nest intruder but never followd the neutral human.

Source: Animal Cognition

Decline of Early Crocodile Helped the Early Marine Turtle

Marine turtles experienced an evolutionary windfall thanks to a mass extinction of crcodyliforms around 145 million years ago. 

Crocodyliforms comprise modern crocodiles and alligators and their ancient ancestors, which were major predators that thrived on Earth millions of years ago. They evolved into a variety of species including smaller  ones that lived on land through to mega-sized sea-swimming species that were up to 12 metres long. However, around 145 million years ago crocodyliforms, along with many other species, experienced a severe decline -- an extinction event during a period between two epochs known as the Jurassic/Cretaceous boundary. 

During this boundary up to 80 percent of species on land and in marine environments were wiped out . This decline was primarily due to a drop in sea level, which led to a closing off of shallow marine environments such as lagoons and coastal swamps. These were the homes and primary hunting grounds for may crocodyliforms. The decimation of many marine crocodyliforms may also have laid the way for their ecological replacement by other large predatory groups such as modern shark species  and new types of plesiosaurs. Plesiosaurs were long-necked, fat-bodied and small headed ocean-going creature with fins, which later went extinct around 66 million years ago.

Other factors that contributed to the decline of marine crocodyliforms included a change in the chemistry of ocean water with increased sulphur toxicity and a depletion of oxygen. While primitive crocodilyform species on land also suffered major declines, the remaining species diversified into new groups such as  the new extinct notosuchians, which were much smaller in size at around 1.5 metres in length. Eusuchians also came to prominence after the extinction which led to today's crocodiles.

For this research work the researchers analyzed almost 1,200 crocodyliforms fossil records.

Source: Biological Science

Lion Escaped from the National Park

A lion named Sylvester, escaped from a South African National Park. Helicopters will be used to track down the three year old animal, which may be put down as a result of his repeated breakouts from Karoo National Park in the South of the country. The same lion escaped from the park previously, that was happened in 2015.

A signal from Sylvester's tracking collar which was fitted after his last escape, showed he was outside the park on this Sunday and by Monday he was 20 km from the park's fenced boundary, in  a mountainous area not easily accessibe by foot. 

He has already killed cow. 

During his last escape,  he roamed 300 km from the park, killing 30 animals over three weeks before being shot by a tranquilizer dart fired from a helicopter. At the time, wildlife officials said he had been forced out of the park by older lions.

Lions were re-introduced to Karoo National Park, western Cape province, in 2010 after an absence of almost 170 years. The last Wild lion in the area was shot in 1842.

Human carbon release rate is unprecedentedd in the past 66 million years of Earth's history

Researchers look at changes of Earth's temperature and atmospheric carbon dioxide (CO2) since the end of the age of the dinosaurs. Their findings suggest humans are releasing carbon about 10 times faster than during any event in the past 66 million years.

The earliest instrumental records of Earth's climate, as measured by thermometers and other tools, start in the 1850s. To look further back in time, scientists investigate air bubbles trapped in ice cores, which expands the window to less than a million years. But to study Earth's history over tens to hundreds of millions of years, researchers examine the chemical and biological signatures of deep sea sediment archives.

Source: Nature Geo-science

Greenland melting tied to Shrinking Arctic Sea Ice

Ice of the arctic sea is vanishing, the weather systems over Greenland is dogged and the far-flung surface ice melting on the massive island.These dramatic trends and global sea-level rise are linked according to the study. 

During Greenland summers, melting Arctic sea ice favors stronger and more frequent blocking-high pressure systems, which spin clockwise, stay largely in place and can block cold, dry Canadian air from reaching the island. The highs tend to enhance the flow of warm, moist air over Greenland, contributing to incresed extreme heat events and surface ice melting, according to the study.

Source: Journal of Climate

Pandas hear more than we do

A new study may help conservationists understand this potential for human activitiws to distrub giant pandas in native habitats. Using captive pandas, conservation scientists worked with animal care specialists to determine pandas' range of hearing sensitivity, discovering that that they can detect sound into the ultrasonic range. Because giant pandas depend in large part on information transmitted through vocalizations for reprodictive success, noise from human activities in or near forest areas could be disruptive.

Source: Zoological Society of San Diego

First Contact with rare Sumatran Rhino in Indonesia's Borneo

The critically endangered rhino was caught in a pit trap this month in East Kalimantan province in an area close to mining operations and plantations where the WWF said it was struggling to survive. 

The female animal, thought to be aged around sic, is now in a temporary enclosure and will later be airlifted by helicopter to a safer habitat on Borneo.
The contact with the rhino comes after environmentalists discovered in 2013 that the Sumatran rhino was not extinct on Indonesian Borneo - as had long been though - when hidden cameras captured images of the animals.

Borneo is the world's third-largest island and is shared between Indonesia, Malaysia and Brunei.
No doubt this is a very important discovery as this rhinos are critically endangered. This discovery is very useful for the conservation of this species.

Source: TOI

International Trade Damages Tropical Nature

According to a new research report, tropical countries incur annual economic losses totaling US$1.7 trillion through destruction of ecosystem services. Countries in the tropics are among the largest global exporters of key agricultural commodities such as oil palm, rice, soybean, sugarcane and cassava.

Environment

The biophysical environment is the biotic and abiotic surrounding of an organism or population, and consequently includes the factors that have an influence in their survival, development and evolution. The biophysical environment can vary in scale from microscopic environment and the terrestrial environment. The number of biophysical environments is countless, given that each living organism has its own environment.

The term environment is often used as a short form for the biophysical environment, e.g. the UK's Environment Agency. The expression "the environment often refers to a singular global environment in relation to humanity."

Ecology

Ecology is the scientific analysis and study of interactions among organisms and their environment. It is an interdisciplinary field that includes biology, geography and Earth science. Ecology includes the study of interactions organisms have with each other, other organism, and with abiotic components of their environment. Topics of interest to ecologists include the diversity, distribution, amount (biomass), and number (population) of particular organism, as well as co-operation and competitive between organisms, both within and among ecosystems.Ecosystems are composed of dynamically interacting parts including organisms, the communities, nutrient cycling, and various niche construction activities, regulate the  flux of energy and matter through an environment. These processes are sustained by organisms with specific life history traits, and the variety of organisms is called biodiversity. Biodiversity, which refers to the varieties of species, genes and ecosystems, enhances certain ecosystem services.

Ecology is not synonymous with environment, environmentalism, natural history or environmental science. It is closely related to evolutionary biology, genetics and ethology. An important focus for ecologists to improve the understanding of how biodiversity affects ecological function. Ecologists seek to explain:

• Life processes, interactions and adaptations
• The movement of materials and energy through living communities
• The successional development of ecosystems
• The abundance and distribution of organisms and biodiversity in the context of the environment

 Ecology is a human science as well. There are many practical applications of ecology in conservation biology, wetland management, natural resource management (agroecology, agriculture, forestry, agroforestry, fisheries), city planning  (urbari ecology), community health, economics, basic and applied science, and human social interaction (human ecology). 

The word 'Ecology' was coined in 1866 by the German scientist Ernst Haeckel.

Extinct Bats Species Discovered in Hawaiian Land

The Hawaiian Islands have long been thought to support just one endemic land mammal in the archipelago's brief geological history, the Hawaiian hoary bat. But  new fossils evidence indicates that a second, very different species of bat lived alongside the hoary bat for thousands of years before going to extinct shortly after human arrived the Islands. The researchers describes the bat whose remains were first discovered in a lava tube more than 30 years ago.

Source: American Museum of Natural History

Most Big Animals Tried Grass but Many Switched Diet or Extinct

As grasses grew more common in Africa, most major mammal group tried grazing on them at times during the past four million years, but some of the animals went extinct or switched back to browsing on trees and shrubs.

Sky Diving Spiders found in S America

Scientists have discovered a type of nocturnal hunting spider in South America, that is able steer while falling. The spider, from the genus Selenops, is the only arachnid that is able to do this. They manoeuvre by spreading their legs in order to use lift and drag to steer themselves towards the tree when they fall. If they fall upside down, they are able to right themselves in midair.

World Without Humans

Researchers have provided the first estimate of how the mammal diversity world map would look like if modern man had never existed. Then most of northern Europe would probably now be home to not only wolves, Eurasian elk and bears, but also animals such as elephants and rhinoceroses.

Researches have based their estimates on the distribution of each species according to its ecology, bio-geography and the current natural environmental template. "Northern Europe is far from the only place in which humans have reduced the diversity of mammals", said Jens-Christian Svenning, from the Department if Bioscience, Aarhus University in Denmark. The current world map of mammal diversity shows that Africa is the only place with a high diversity of large mammals.

However, the world map shows far greater distribution of high large-mammal diversity across most of the world,with particularly high levels in North and South America.

"Most safaris today take place in Africa, but under natural circumstances, as many or even more large animals would no doubt have existed in other places such as Texas and region around northern Argentina-Southern Brazil", said lead author Soren Faurby.

World Without Us 

Ladybird colors reveal their toxicity

For one of Britain's best-loved and colorful group of insects, ladybirds, the brightness of their color reveals the extent of their toxicity to predators, according to new research. Although red ladybirds with black spots are most familiar, ladybirds are a diverse group of species and come in many different colors and patterns, from yellow and orange to even camouflaged browns. 

Lina María Arenas, a PhD student at the Centre for Ecology and Conservation at the University of Exeter and from the University of Cambridge said: "Ladybird beetles are one of the most cherished and charismatic insects, being both beautifully colored and a friend to every gardener. Our study shows that not only does ladybird color reveal how toxic they are to predators, but also that birds understand the signals that the ladybirds are giving. Birds are less likely to attack more conspicuous ladybirds."

Although red ladybirds with black spots are most familiar, ladybirds are a diverse group of species and come in many different colors and patterns, from yellow and orange to even camouflaged browns. The bright coloration of different ladybird species acts as a warning signal, telling potential predators to beware of the foul smelling, poisonous chemicals they use for defence.

The researchers measured toxicity using a biological assay, by counting the number of dead Daphnia -- tiny crustaceans -- in water containing the different ladybird toxins. The results show that five common ladybird species each have different levels of toxic defence. Those species with the most colorful and conspicuous colors against the natural vegetation where they live are also the most toxic.

Dr Martin Stevens from the University of Exeter said: "Our results tell us that the ladybirds present 'honest' signals to predators, because their color reveals how well defended they are.

"Relatively inconspicuous species, such as the larch ladybird, have low levels of defence and place more emphasis on avoiding being seen, whereas, more conspicuous and colorful species, such as the 2-spot ladybird, openly flaunt their strong defences to predators like birds."

Modified cameras that are sensitive to ultraviolet light were used to photograph the ladybirds, allowing the researchers to use special modelling and image analysis techniques to analyse how each species would appear to predatory birds, which have very different color vision to humans.

To test how likely each species was to be attacked, artificial versions of each ladybird species were presented to wild birds. The birds were able to recognise the differences in coloration between the prey, and were least likely to attack the brighter, more conspicuous ladybird species.

The study is the first to comprehensively show that the level of colorfulness and conspicuousness of different species with warning signals reveals how toxic they are, and that in turn more toxic and colorful species are less likely to be attacked in the wild.

This story is taken from Science Daily

Recovering predators create new wildlife management challenges

A new study examines recovering predator populations along the West Coast of the United States and in the Greater Yellowstone ecosystem, and the conflicts surrounding them. 

The study by scientists from NOAA Fisheries' Northwest Fisheries Science Center and the University of Washington examines recovering predator populations along the West Coast of the United States and in the Greater Yellowstone ecosystem, and the conflicts surrounding them. The study was published in the journal Conservation Letters.
In the Pacific Northwest, for example, California sea lions that have increased under the Marine Mammal Protection Act have increasingly preyed on endangered salmon. Wolves reintroduced to Yellowstone in 1995 have since cut into elk herds, reducing human hunting opportunities.
"Increases in predators can be seen as successful in terms of efforts to recover depleted species, but may come at a cost to other recovery efforts or harvest of the predators' prey," said Eric Ward, a NOAA Fisheries biologist and coauthor of the paper.
The scientists describe three types of conflicts that can emerge as predators rebound under the protection of the Endangered Species Act and Marine Mammal Protection Act:

• Increased competition with humans for the same prey. For instance, sea lions eating fish also pursued by anglers and wolves preying on livestock and reducing elk numbers.
• Predators consuming protected or at-risk prey species, such as sea lions eating salmon and grizzlies consuming Yellowstone cutthroat trout.
• Protected predators competing with each other for prey. For example, sea lions consuming the same fish as killer whales, with wolves and grizzly bears also preying on the same species.

Pacific Northwest waters include many such conflicts, largely because many top predators such as sea lions, elephant seals and several whales are increasing in number and prey upon salmon, steelhead, rockfish and other fish protected by the Endangered Species Act.
Conservation conflicts have also emerged elsewhere: On California's San Clemente Island, a threatened island fox species preys on an endangered shrike, while protected golden eagles prey on both the fox and the shrike. Also in the Pacific Northwest, protected barred owls are moving into forest habitat long important to threatened spotted owls and double-crested cormorants, like sea lions, have been targeted for culling to reduce predation on Columbia River salmon.
The scientists call for improved monitoring and modeling to better anticipate interactions between predators and prey, and assess whether steps to manage predators may be warranted. Where conflicts continue, the scientists suggest developing multi-species recovery plans that consider the tradeoffs between increasing predators and other protected species.
"Predators such as bears, wolves and whales are charismatic creatures often seen as bellwethers of ecosystem health," said Kristin Marshall, a postdoctoral researcher at NOAA Fisheries who completed graduate research in Yellowstone and lead author of the paper. "We're fortunate to have places such as Yellowstone and the Northeast Pacific where they can recover, but in protecting one species you have to be thinking ahead to account for cascading effects that may impact other species too."
The ESA and MMPA do recognize larger ecosystem needs. For instance, the first purpose of the ESA is "to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved," and the MMPA seeks to "maintain the health and stability of the marine ecosystem." Both NOAA Fisheries and public land managers in the Yellowstone region are increasingly pursuing ecosystem-based management with those goals in mind. Research has also found ecological benefits from the reintroduction of wolves in Yellowstone.
Both the ESA and MMPA also provide safety valves by allowing limited control of recovering predators to manage their impacts under certain circumstances.
NOAA Fisheries has authorized states under the MMPA to remove sea lions known to be preying on endangered salmon, for instance. An "experimental" designation under the ESA allowed for removal of wolves that attacked livestock, although wolves are no longer listed as endangered in Montana and Idaho and are now subject to hunting.
But the scientists note that resolving conflicts by culling predators may itself have unintended consequences and will face public and legal opposition that may limit management options.
"Thirty years ago scientists predicted that increases in predator populations would cause more of these conflicts to emerge," Ward said. "We've largely seen these predictions come true, and there's no indication of these conflicts decreasing."

This story is taken from Science Daily