The parade is underway and you don’t want to miss it, because once it’s gone, it won’t be coming by again for another six or seven months. It is not the coming of colder weather that sends the birds south, that it reserved for the realm of human ‘snowbirds’. Rather, birds are responding to the shortening daylight and the reduction in food supplies (insects and flower nectar in particular). But this is all the more reason for us to keep our bird feeders well stocked.
Migration is a risky business and there are millions of birds that have just hatched this past spring and summer and they are at the greatest risk for survival. Threats range from human structures (cell towers and skyscrapers) to weather, to predators (such as domestic cats and raptors). It takes a great deal of energy to fly the thousands of miles many will cover during their return south, and so they are stopping wherever food supplies are good to build up fat that can be burned during flight.
The many varieties of warblers are mostly insect eaters and one good source of food and energy during this time is suet. These blocks of concentrated energy can contain fats, berries, nuts or seeds, depending on the type you choose. We have seen warblers at our suet feeders in both spring and fall, especially on the colder days. They may not be in their bright breeding plumage at this time, but it is still a delight to see them.
Yellow-rumped warblers and a pine warbler at the suet feeder
Radar image of birds in migration on September 2, 2015
Besides providing food, there are a number of things you can do to help birds during this autumn migration season.
In recent years science has allowed us to witness this massive movement of birds through radar images. Songbirds generally take to the air around sunset, and as they do, they rise up in the atmosphere through the radar beams, creating these circles of intensity of material in the air. They look like flowers blooming on the radar if you do a loop between sunset and about an hour after sunset. The biggest clue is that these patterns are circular. Weather tends to be oblong. Also, weather tends to move across a radar screen, while these are simply blooming circles of radar.
If you look at different weather patterns, you will see that these radar “blooms” disappear ahead of, and behind storm cells that are moving through an area, as the birds take cover and don’t migrate through the storm cells. In the morning, these circles shrink in color and size as the birds come down out of the atmosphere to the ground to rest for the day.
Keep those bird seed and suet feeders filled and wish your feathered visitors safe travels.