I think the solution to the decline of a birds is
a $100 bounty on every house cat found outdoors.

Cats are the Number 1 Threat to Birds

Predation by domestic cats is the number-one direct, human-caused threat to birds in the United States and Canada.

In the United States alone, outdoor cats kill approximately 2.4 billion birds every year. Although this number may seem unbelievable, it represents the combined impact of tens of millions of outdoor cats. Each outdoor cat plays a part.