Development pressures are a leading cause of habitat destruction and biodiversity loss within and around National Wildlife Areas and Migratory Bird Sanctuaries. Urban sprawl is encroaching on many of these sites in British Columbia, Ontario, Quebec and the Maritime provinces. The northward expansion of forestry and oil and gas development is destroying and fragmenting northern ecosystems.

In addition, exotic (non-native) species are frequently introduced by new operations and housing tracts, competing with and displacing native wildlife, and increased public access —in particular poachers and people driving off-highway vehicles into fields and woods — significantly disturb wildlife.

Three cases of development pressure:

Hydro dams and the Richardson Lake Migratory Bird Sanctuary in Alberta
Alberta’s Richardson Lake Migratory Bird Sanctuary forms part of the Peace Athabasca Delta, an internationally recognized wetland and one of the largest freshwater deltas in the world. The construction of two upstream hydroelectric dams has disrupted the delta’s water levels causing a great reduction in its ability to support wildlife, like the black terns that inhabit the area.

Cranberry farm operations impact New Brunswick’s Portobello Creek National Wildlife Area
New Brunswick’s Portobello Creek National Wildlife Area protects part of the largest wetland complex in Atlantic Canada. Unfortunately, large-scale commercial cranberry facilities on adjacent private lands are fragmenting and contaminating the wetland. So far these facilities have resulted in the clearing of forests, the changing of seasonal flooding and hydrology patterns, and the silting of the adjacent Portobello River. When 30,000 acres of adjacent, privately owned wetlands came up for sale, the federal government lacked the resources to purchase the land. It was purchased privately for logging and is now being clear-cut.

Oil and gas development in Kendall Island Migratory Bird Sanctuary
Companies are pressing the federal government to develop petroleum reserves in the Kendall Island Migratory Bird Sanctuary in the Northwest Territories.

Recently, the Cheviot Mine has become a major concern to Nature Canada:

Proposed open-pit coal mine development next to Jasper National Park threatens grizzlies
The federal government has authorized mining activities that will result in the destruction of the habitat for grizzlies and thousands of migratory birds despite serious concerns from conservation groups from across the country and federal government officials.

Environmental groups assert that the project has changed significantly since it was first proposed in 1996 and that a new environmental assessment is required.