What is a ';wildlife corridor'; and why is there controversy over their use?

What is a corridor, advantages and especially disadvantages. When is a time when a corridor might be a ';bad'; idea? What are implications of connecting a ';sink'; to a reserve network?What is a ';wildlife corridor'; and why is there controversy over their use?
A wildlife corridor is a stretch of land (relatively long and narrow) that wildlife uses to get from one place to another. It might connect feedin and nesting grounds, for example. It can also be a stretch of land that connects one population to another.





Problems arise when developers and urban planners plunk a road down across the corridor and defend it by saying, ';But we're only taking 10% of the habitat.'; Unfortunately, that is sometimes enough to separate the population from a vital resource.