Question: Policy vs. Conservation

Addressing a scientific audience, I pose a question. How does your research influence or impact policy making and conservation? Does it actually contribute?
There is a growing idea in conservation science that we cannot completely comprehend the complexities of the natural environment. The demand for ecosystem based approaches to conservation and management is increasing, but as ecologists are we actually able to justify and deliver the answers being sought by our governments, and do these governments actually understand what we've done? What is the value of small scale, petri dish experiments in the bigger picture compared to large scale field manipulations, in terms of conservation (there is no doubt as to the value of small scale experiments for understanding ecology from a mechanistic approach)? Can our models truly be applied in realistic scenarios? Is biodiversity an appropriate indicator for the need for conservation, or should this type of research be focussed more towards ecosystem functioning and ecosystem services?
I am just curious about your opinions on these questions...