This video from Arkansas in the USA is called Importance of Bird Conservation.
From daily The Guardian in Britain:
Some rarer birds have grown in number over last 30 years due to conservation efforts while some well known species have fallen
Sunday 2 November 2014 16.08 GMT
Bird populations across Europe have decreased by over 420 million in the past 30 years, according to a study that brings together the results of scientific surveys in 25 countries. While some rarer species have seen an increase in numbers due to concerted conservation efforts, more common species across Europe are facing a steep decline.
Some of the birds that have suffered the most alarming declines are the most well known species including the house sparrow which has fallen in number by 147m or 62%, the starling (53%) and skylark (46%).
The study looked at 144 species across Europe between 1980 and 2009. Dividing the species up into four groups, from extremely rare to most common, analysts found that a small number of common species declined by over 350 million –over 80% of the total population decline of birds in that time period overall. Rarer birds, in contrast, increased by over 21,000 in the same time period.
The results indicate that efforts at conserving rarer species seem to be having an impact but may be too narrow an approach, possibly at the expense of more common species.
“The focus up to this point has very much been on conserving rare species,” says the lead author, Richard Inger, from the University of Exeter. “That’s what it should be, in many ways, but the issue there is that if you’re not careful, you can spend all of your conservation dollars on just protecting the rare things. You can take your eye off the ball, if you will.”