加拿大開採油砂礦 數億鳥兒受威脅

Exploitation of Canada's tar sands, the world's largest proven oil reserves outside Saudi Arabia, is damaging forest and wetland habitats in Canada's northern boreal forest, new research shows. The oil sands development could claim more than 160 million boreal birds, the peer-reviewed study predicts.

The report is the joint product of research by the Pembina Institute, a nonprofit research organization with offices across Canada, the Seattle-based Boreal Songbird Initiative, and the Natural Resources Defense Council, a U.S. national research and advocacy group.

The report, "Danger in the Nursery," says that almost all the world's biggest oil companies are involved in tar sands extraction in an area of northeastern Alberta, which supports at least 292 species of breeding birds.

Many of the most abundant songbirds and waterbirds of the Americas also breed in the "bird nursery" of the boreal forest, and are already suffering declines because of logging, and degradation of their migration staging sites in addition to the risks posed by tar sands development.

Site preparation for strip mining of the tar sands requires draining lakes and wetlands, diverting streams and rivers, clearcutting forests, and removing all vegetation. Hydraulic shovels and trucks are used to dig as deep as 100 meters into the earth.

The report's lead author, Dr. Jeff Wells, is senior scientist for the Boreal Songbird Initiative. "Strip mining is projected to destroy up to 300,000 hectares of boreal forests and wetlands. But more than 80 percent of established tar sands reserves are too deep for recovery via strip-mining and must instead be extracted using in-situ drilling techniques that need a dense network of roads, pipelines, compressor stations and energy generation facilities, which will eventually destroy more habitat than strip mining."

Among globally threatened species are the rusty blackbird, Euphagus carolinus, and Sprague's pipit, Anthus spragueii, both Vulnerable, and the olive-sided flycatcher, Contopus cooperi, which is classed as Near Threatened.

The only wild, migratory population of the Endangered whooping crane, Grus americana, nests at Wood Buffalo National Park to the north, and migrates over the tar sands region, occasionally stopping over at boreal wetlands.

"Canada's boreal forest is an incredibly important area for many breeding neotropical migrant birds, and contains numerous Important Bird Areas", said John Cecil, national IBA program director for the National Audubon Society. "The report details impacts to at least five IBAs, among numerous other impacts."

The term tar sands refers to thick oil called bitumen that is mixed in with sand, clay, and water. The mining, extracting and upgrading it into synthetic crude produces greenhouse gas pollution. Producing one barrel of synthetic crude oil generates three times the greenhouse gas emissions of a barrel of conventional oil.

Tailings ponds filled with toxic mining waste present a high risk to migrating waterbirds, since they remain open when natural water bodies are frozen. In April last year, around 500 ducks died after landing on a tailings pond near a tar sands operation in northern Alberta.

Tailings ponds filled with toxic mining waste present a high risk to migrating waterbirds, since they remain open when natural water bodies are frozen. In April last year, around 500 ducks died after landing on a tailings pond near a tar sands operation in northern Alberta.