Every year millions of birds migrate from the tropics to the Northern US and Canada to breed during the short summer season. The plentiful insects allow for their young to grow up quick and strong enough to fly back south with them in fall. The undeniable benefits to migration are clear but to every action there in an equal and opposite reaction. In this case, millions of birds leave the tropics, but many will die on the journey to and from the breeding grounds. Let’s take a brief look at some of the top causes of bird mortality:
* Numbers are based on chart from Sibleysguides.com. Data is from 2003
- Windows – Approximately 980 million birds per years *
- Cats- Approximately 500 million per year *
- High tension wires and communication infrastructure- between 5 and 50 million per year. Number is hard to estimate. *
- Cars- Approximately 60 million per year. *
- Pesticides- Approximately 72 million *
There are any number of other ways birds end up dead but the problems listed above are the ones that can either be prevented or mitigated by people. Many of these deaths can be prevented by simple keeping cats inside and pulling blinds when you aren’t in a room. By inventing new ways of reducing bird mortality, we can assure that migration and birding can go on for many years to . come.
* Numbers are based on chart from Sibleysguides.com. Data is from 2003