The plan will allocate $252 million over the next five years for projects across the country and about $100 million of that will go to the Nature Conservancy of Canada to secure ecologically sensitive lands.
"As we respond to the conservation challenges of today, we believe it's important that all Canadians, urban and suburban as well as rural, share the vision and the experience of a healthy environment," Harper said while in the village of New Maryland, N.B., near Fredericton.
"Our national conservation plan will therefore support initiatives to make it easier for urban Canadians to connect with nature and it is our hope that as they enjoy, appreciate and understand this great land just as their forebears did, they will be drawn to work together for its conservation."
The plan also includes $37 million to strengthen marine and coastal conservation and $3.2 million to develop a national inventory of conserved areas. The government said $50 million would go toward restoring wetlands.
NDP environment critic Megan Leslie accused the Conservatives of pretending to be concerned about the environment and engaging in a public relations exercise.
"This is the same Conservative government that gutted environmental assessment laws, the same Conservative government that took away the protection of fish habitat," she said. "Their track record really undermines anything that they purport they're going to do."
Leslie also said it wasn't clear if the plan includes any new money or just a reannouncement of funds. In fact, she said the announcement was so devoid of details that she couldn't say whether it contained anything positive at all.
"We don't have a document in our hand, we just have the prime minister standing behind a podium," she said.
The federal Conservatives promised during the 2011 election campaign and again in last year's throne speech to establish a national conservation plan.
Harper also said the oft-mentioned plan complements proposed 2020 biodiversity goals and targets.
But Eric Hebert-Daly, national executive director of the Canadian Parks and Wilderness Society, said the government hasn't been clear how it intends to protect 10 per cent of its marine ecosystems and 17 per cent of its land within the next six years.
"This obviously sounds like it might be a step forward," he said. "We don't actually have the details on how this will play itself out."
Hebert-Daly said the conservation plan lacks mention of money for national parks and scientific monitoring, but he was pleased with the investment in marine conservation, particularly if it means the establishment of a network of protected areas.
"That would be fantastic and long-needed news," he said.
John Lounds, president of the Nature Conservancy of Canada, said his organization will work with local groups and communities across the country for matching funds for projects across Canada.
"A lot of the land that's important from a conservation standpoint is in private hands," he said. "The reason it's that way is that those people have been taking care of it over many, many years. So what we do is work with them to figure it out how we do that for the long term."
He said the new plan builds on a plan in place for the last six years.
"There's some new elements to this conservation plan that weren't part of the last," he said. "There's a wetlands restoration program and there are also other private initiatives. So when you look at the whole package, it is very similar and probably more than was done before."
— With files from Melanie Patten in Halifax.
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