You'll have to cut and pate as my ability to drop in a link seems to be lacking today...

Smithsonian article: http://www.smithsonianmag.com/ist/?n...ill-180948154/

Biological Conservation report: http://www.sciencedirect.com/science...06320713003522

This article has links to 2 studies, one lists the results of the 2009 US Fish and Wildlife report, the other is a by someone else, but more recent : http://www.birdwatchingdaily.com/blo...rms-last-year/

Here is the link to the Abstract by K. Shawn Smallwood, MAR 2013, full article requires membership: http://onlinelibrary.wiley.com/doi/1...b.260/abstract

Why is everyone so lazy that they need to be spoon fed this? Is your Google-Fu that weak?

I'm not posting for one side or the other, just to show if one wants data, it is out there. I guess whomever reads any of this will need to determine if they are "reliable" sources or not.