birds in north america

Birds in North America are getting smaller because of climate change
A study of nearly 40 years on tens of thousands of birds killed by flying high-rise buildings in Chicago (USA) found that their size diminishes over time due to climate change.
Half a century, North America alone lost 3 billion birds
Scientists say the number of birds in the US and Canada has dropped by an astounding 29%, or nearly 3 billion, since 1970. This is a sign of the birth crisis. Thailand is