TORONTO - Ontario's environmental watchdog is raising the alarm about the use of neonicotinoid pesticides, which have been linked to deaths of bees.

Environmental Commissioner Gord Miller says declines in honey bee populations may be a warning sign of a larger ecological problem, and says the pesticides are persistent in soil and water and highly mobile within ecosystems.

In his annual report, Miller also calls on the government to ban logging in Algonquin Park, the only one of the 339 provincial parks where timber harvesting is allowed.

The commissioner says the Environment Ministry must do more to resolve what he calls the health crisis at a First Nation near Sarnia, which receives millions of kilograms of air pollution from the nearby petro-chemical complex known as "chemical valley."

He calls the situation a "historic failure," and says it's "truly shameful" that a promised review of the cumulative effects of air pollution on the Aamjiwnaang First Nation still isn't done after five years.

Miller also slams the Liberal government's efforts to control urban sprawl in the Greater Golden Horseshoe from Niagara to Toronto, saying allowing low density projects only puts pressure on municipalities to open more lands for development.