Sunday 22 March 2015

Mass extinction

Buzzing off! 1 in 10 wild bees faces extinction in Europe, study warns


Reuters / Mike Blake

RT,
21 March, 2015

Nearly 10 percent of some 2,000 species of European wild bees face extinction, says a recent study, adding that the drivers behind such a mass disappearance of nature’s top pollinators include the use of insecticides, fertilizers, and climate change.

Overall, 9.2 percent of bees are considered threatened in Europe, while at the EU-27 level, 9.1 percent are threatened with extinction,” says a new report published as a part of the IUCN (International Union for Conservation of Nature) European Red List of Bees project.

The study, co-funded by the European Commission, gives information about 1,965 wild bee species in Europe, including their status, distribution and the dangers they face.

Distribution of threatened bees in Europe. (image from http://ec.europa.eu)
Distribution of threatened bees in Europe. (image from http://ec.europa.eu)

The main threats to bee survival are connected with modern agriculture, says the report, adding that these hazards include intensive arable farming, livestock farming and the continued presence of commercial timber plantations. Climate change may also contribute to mass bee extinction.

READ MORE: Scientists confirm: Pesticides kill America's honey bees

Bees “are threatened with extinction in Europe mainly due to habitat loss as a result of agriculture intensification (e.g., changes in agricultural practices including the use of pesticides and fertilizers), urban development, increased frequency of fires and climate change,” says the study.

Also herbicides can also negatively affect bee diversity, as they “can reduce the availability of flowers on which bees depend and delay the flowering, so the timing between the period when food is most needed by pollinators and food availability is disrupted.”

Our quality of life – and our future – depends on the many services that nature provides for free. Pollination is one of these services, so it is very worrying to learn that some of our top pollinators [bees] are at risk!” said Karmenu Vella, European Commissioner for Environment, Maritime Affairs and Fisheries.

If we don’t address the reasons behind this decline in wild bees, and act urgently to stop it, we could pay a very heavy price indeed,” he dded.

READ MORE: 5,000 bees chilled, shaved and microchipped in Australian study to prevent killer diseases

Major threats to bees in Europe. (image from http://ec.europa.eu)
Major threats to bees in Europe. (image from http://ec.europa.eu)

Knowledge about wild bees in Europe is “incomplete, as we are faced with an alarming lack of expertise and resources,” says Jean-Christophe ViĆ©, deputy director of the IUCN Global Species Programme.

Bees play an essential role in the pollination of our crops. We must urgently invest in further research in order to provide the best possible recommendations on how to reverse their decline,” he said.

READ MORE: 'Beemageddon' delayed: Bumblebee reemergence puzzles scientists
According to the report, every year bees provide crop pollination worth €153 billion globally and €22 billion in Europe.

Population trends of European bees. (image from http://ec.europa.eu)
Population trends of European bees. (image from http://ec.europa.eu)

In terms of global agricultural production volumes, 35 percent comes from crops that depend on pollinators, mainly insects. Out of the 124 main crops grown for global human consumption, 87 (70 percent) require insect pollination for seed production.”



World’s forests are fragmenting into tiny patches – risking mass extinctions
David Edwards
Lecturer of Conservation Science at University of Sheffield


21 March, 2015


A dam in Indonesia splits the forest in two. Bagus Indohono / EPA

Much of the Earth was once cloaked in vast forests, from the subarctic snowforests to the Amazon and Congo basins. As humankind colonised the far corners of our planet, we cleared large areas to harvest wood, make way for farmland, and build towns and cities.

The loss of forest has wrought dramatic consequences for biodiversity and is the primary driver of the global extinction crisis. I work in Borneo where huge expanses of tropical forest are cleared to make way for palm oil plantations. The biological cost is the replacement of some 150 forest bird species with a few tens of farmland species. But forest is also frequently retained inside or at the edges of oil palm plantations, and this is a pattern that is replicated globally.

The problem, according to new research published in Science Advances, is that the vast majority of remaining forests are fragmented. In other words, remaining forests are increasingly isolated from other forests by a sea of transformed lands, and they are found in ever-smaller sized patches. The shockwaves of loss thus extend far beyond the footprint of deforestation.


Accessible forests

 
The great outdoors? Only the blue areas are more than 1km from the edge of the forest. Joe Sexton/Danxia Song


The team, led by Nick Haddad from North Carolina State University, used the world’s first high-resolution satellite map of tree cover to measure how isolated remaining forests are from a non-forest edge. Edges are created by a plethora of deforesting activities, from roads to cattle pastures and oil wells, as well as by rivers.
They found that more than 70% of remaining forest is within just 1km (about 0.6 miles) of an edge, while a 100 metre stroll from an edge would enable you to reach 20% of global forests.

Comparing across regions, the patterns they find are even starker. In Europe and the US, the vast majority of forest is within 1km of an edge – some of the most “remote” areas in these regions are a stones throw from human activity. “Getting away from it all” has never been more challenging.

If you want remote forests on a large scale you’ll have to head to the Amazon, the Congo, or to a lesser degree, central and far eastern Russia, central Borneo and Papua New Guinea.


Biodiversity reduced


These findings wouldn’t be cause for alarm if wildlife, forests, and the services that they provide humankind such as carbon storage and water, were unaffected by fragmentation. However, by drawing together scientific evidence from seven long-term fragmentation experiments, Haddad and colleagues show that fragmentation reduces biodiversity by up to 75%. This exacerbates the extinction risk of millions of forest species, many of which we still don’t know much about.


For undisturbed forest, head to Congo’s blue zone. Joe Sexton/Danxia Song

Forest species struggle to survive at edges because these places are brighter, windier, and hotter than forest interiors. Edges become choked by rampant vines and invaded by disturbance-tolerant, parasitic or invasive species that outcompete the denizens of dark forest interiors. In Borneo, for example, small forest patches house bird communities that are far more similar to those found in the surrounding oil palm than to those of larger forest tracts.

The survival of large, carbon-rich trees – the building blocks of any intact forest ecosystem – is reduced in smaller and more isolated forest fragments. These patches thus fail to maintain viable populations, which over time are doomed – an “extinction debt” yet to be paid.


Curassows hate deforestation. fPat Murray, CC BY

With so much global forest in close proximity to humans, larger forest animals such as chimpanzees, gorillas, tapirs or curassow birds are being hunted to extinction in individual areas. This shifts animal communities within the forest fragments to one dominated by small-bodied species. Further, hunters are willing to penetrate forests for several kilometres from edges in search of game, effectively making the truly wild global forest estate yet smaller.


Difficult management decisions


The insidious effects of fragmentation mean that the top conservation priority must be preventing further incursions into dwindling wildernesses. By preventing the first cut we can help to prevent global fragmentation and the further loss of biodiversity.

Of course, we should not ignore fragmented regions. Some of these, including the Brazilian Atlantic forest, Tropical Andes and Himalayas, share a toxic mix of hyperdiversity, endemic species with tiny ranges, and severe fragmentation. The critically-endangered Munchique wood-wren, for instance, exists only in a handful of peaks in the Colombian Andes, but these are now isolated from each other by cattle pastures and roads. Here we must seek to restore forest cover and improve connectivity between larger fragments if we are to prevent extinctions.


Large patches of the Amazon remain, but Brazil’s Atlantic forest is rarely more than 1km from an edge. Clinton Jenkins

However, the rapid expansion of human populations, greed, and meat consumption mean that more forest is likely to be lost, even if farm yield and efficiency can be improved to help bridge gaps between current and future demand. The difficult question is where should this expansion happen? Given the severe degradation of small and isolated fragments, perhaps conversion could target some of these patches, coupled with wilderness protection and expansion.


Forest fragmentation in the Peak District. Dan Cook, CC BY-SA

Next time I visit my local National Park – the highly fragmented Peak District – I will spare a thought for the species that are being harmed by their habitats being broken up into ever smaller chunks. There are no easy answers to the problems of fragmentation, but our forests urgently need a global management plan


Warmer Pacific waters, other factors may be harming marine life



18 March, 2015

Record-high sea-surface temperatures in the Gulf of Alaska and die-offs of sea lions and seabirds on the West Coast are raising concerns about changing conditions in the Pacific.

A report released this week by the U.S. National Oceanic and Atmospheric Administration (NOAA) says a massive “warm blob” of water that is up to 3 C higher than average is spreading south from Alaska. That, together with other environmental factors, could make the ocean less productive for many species, including salmon.

The changes are occurring in addition to an El Nino event that developed in the Pacific this winter, and which brought warmer water north from the equatorial Pacific. The warm waters in Alaska developed about one year ago.

We are seeing unprecedented changes in the environment,” Toby Garfield, director of the environmental research division at the U.S. Southwest Fisheries Science Center said in a statement.

The report states that, in addition to higher sea-surface temperatures, there have also been weaker upwellings of cold currents. Those upwellings bring nutrients up from deeper ocean levels, enriching the base of the marine food web.

The NOAA report states that last summer and fall, the weights of California sea lion pups were below average in some rookeries, and many pups died, apparently from starvation.

That trend has continued into winter, along with strandings of dead pups. It is possible that another UME [unusual mortality event] will be declared soon in 2015,” the report states.

The NOAA report also says that Cassin’s auklets, especially juveniles, have been dying in large numbers.

Many dead auklets appear emaciated. Cassin’s auklets prey on zooplankton, and this die-off may be a leading indication of suboptimal feeding conditions,” the report states.

Dr. David Bradley, B.C. program manager of Bird Studies Canada, said Wednesday there is “definitely a spike in [marine bird] casualties in B.C. this winter.”

But he said “it’s a big mystery” as to why the birds have been dying and he is waiting to see whether U.S. researchers can confirm a correlation between marine-bird deaths and warmer sea-surface temperatures.

Dr. Richard Beamish, an emeritus scientist with the Department of Fisheries and Oceans, said the NOAA study suggests a significant shift of oceanic conditions is taking place.

Some of us, me in particular, believe there are these major climate, ocean events which we’ve been calling regimes,” he said. “We had a major regime shift in ’77 and then in ’89, probably another around 1998 … and since they [are] occurring roughly every 10 years … most of us have been expecting we’d see a change.”

Dr. Beamish said regime shifts can have a dramatic impact on salmon production, causing stocks to crash.

But some fish species thrive under warmer conditions, and fish rarely seen off the West Coast can become plentiful.

We could have a bizarre season, perhaps with tuna up as far as Alaska,” he said.

Aaron Hill, executive director of Watershed Watch Salmon Society, said the changes are worrying.

It’s certainly concerning, because there are a number of factors in addition to this that are conspiring against B.C. salmon populations,” he said, noting low snowpacks this winter will lead to reduced river levels. “If we get another hot summer on top of that, it will be really bad [for spawning salmon].”

Mr. Hill urged government to restrict commercial catch levels this year.

I’d like to see [Fisheries and Oceans] take a more precautionary approach to salmon populations under these conditions,” he said. “They are basing management decisions on the assumption we have a certain level of productivity in our salmon populations. But with these environmental conditions right now, that seems like a brash assumption.”



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