The feral pig is also a major threat to Hawaii's natural ecology.

Other environmental leaders have excluded humans from their conception of the natural ecology.

Many conservation biologists see the struggle to reach some accommodation between the interests of the Plains economy and its natural ecology as critical.

This had little effect on the river's natural ecology.

They believe that natural ecologies, like the free markets, are dynamic and self-adjusting systems.

Agriculture, by definition, involves a disturbance of the natural ecology.

But this was definitely not a natural ecology.

Preserving the island's natural ecology has always been important to its citizens and visitors alike.

Since then, the construction of fish cages has long been a problem for the river's natural ecology.

The natural ecology of Schizosaccharomyces yeasts is not well studied.