Humans harnessing of technology and targeting adult rather than juvenile prey makes us SUPER PREDATORS, causing extinctions, shrinkage in size of remaining prey animals and disrupting the global food chain................"It’s frightening but true ,,,,,Our planet is now in the midst of its sixth mass extinction of plants and animals — the sixth wave of extinctions in the past half-billion years".............. "We’re currently experiencing the worst spate of species die-offs since the loss of the dinosaurs 65 million years ago"................. "Although extinction is a natural phenomenon, it occurs at a natural “background” rate of about one to five species per year"............ "Scientists estimate we’re now losing species at 1,000 to 10,000 times the background rate, with literally dozens going extinct every day".............. I"t could be a scary future indeed, with as many as 30 to 50 percent of all species possibly heading toward extinction by mid-century

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Are humans unsustainable 'super predators'? 

Want to see what science now calls the world's "super predator"? Look in the mirror.

Research published today in the journal Science by a team led by Dr. Chris Darimont, the Hakai-Raincoast professor of geography at the University of Victoria, reveals new insight behind widespread wildlife extinctions, shrinking fish sizes and disruptions to global food chains.

"These are extreme outcomes that non-human predators seldom impose," Darimont's team writes in the article titled "The Unique Ecology of Human Predators."

"Our wickedly efficient killing technology, global economic systems and resource management that prioritize short-term benefits to humanity have given rise to the human super predator," says Darimont, also science director for the Raincoast Conservation Foundation. "Our impacts are as extreme as our behaviour and the planet bears the burden of our predatory dominance."

The team's global analysis indicates that humans typically exploit adult fish populations at 14 times the rate of marine predators. Humans hunt and kill large land carnivores such as bears, wolves and lions at nine times the rate that these predatory animals kill each other in the wild.

Humanity also departs fundamentally from predation in nature by targeting adult quarry. "Whereas predators primarily target the juveniles or 'reproductive interest' of populations, humans draw down the 'reproductive capital' by exploiting adult prey," says co-author Dr. Tom Reimchen, biology professor at UVic. Reimchen originally formulated these ideas during long-term research on freshwater fish and their predators at a remote lake on Haida Gwaii, an archipelago on the northern coast of British Columbia.
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THE EXTINCTION CRISIS

It’s frightening but true: Our planet is now in the midst of its sixth mass extinction of plants and animals — the sixth wave of extinctions in the past half-billion years. We’re currently experiencing the worst spate of species die-offs since the loss of the dinosaurs 65 million years ago. Although extinction is a natural phenomenon, it occurs at a natural “background” rate of about one to five species per year. Scientists estimate we’re now losing species at 1,000 to 10,000 times the background rate, with literally dozens going extinct every day [1]. It could be a scary future indeed, with as many as 30 to 50 percent of all species possibly heading toward extinction by mid-century [2].

Unlike past mass extinctions, caused by events like asteroid strikes, volcanic eruptions, and natural climate shifts, the current crisis is almost entirely caused by us — humans. In fact, 99 percent of currently threatened species are at risk from human activities, primarily those driving habitat loss, introduction of exotic species, and global warming [3]. Because the rate of change in our biosphere is increasing, and because every species’ extinction potentially leads to the extinction of others bound to that species in a complex ecological web, numbers of extinctions are likely to snowball in the coming decades as ecosystems unravel.

Species diversity ensures ecosystem resilience, giving ecological communities the scope they need to withstand stress. Thus while conservationists often justifiably focus their efforts on species-rich ecosystems like rainforests and coral reefs — which have a lot to lose — a comprehensive strategy for saving biodiversity must also include habitat types with fewer species, like grasslands, tundra, and polar seas — for which any loss could be irreversibly devastating. And while much concern over extinction focuses on globally lost species, most of biodiversity’s benefits take place at a local level, and conserving local populations is the only way to ensure genetic diversity critical for a species’ long-term survival.

In the past 500 years, we know of approximately 1,000 species that have gone extinct, from the woodland bison of West Virginia and Arizona’s Merriam’s elk to the Rocky Mountain grasshopper, passenger pigeon and Puerto Rico’s Culebra parrot — but this doesn’t account for thousands of species that disappeared before scientists had a chance to describe them [4]. Nobody really knows how many species are in danger of becoming extinct. Noted conservation scientist David Wilcove estimates that there are 14,000 to 35,000 endangered species in the United States, which is 7 to 18 percent of U.S. flora and fauna. The IUCN has assessed roughly 3 percent of described species and identified 16,928 species worldwide as being threatened with extinction, or roughly 38 percent of those assessed. In its latest four-year endangered species assessment, the IUCN reports that the world won’t meet a goal of reversing the extinction trend toward species depletion by 2010 [5].

What’s clear is that many thousands of species are at risk of disappearing forever in the coming decades.

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