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Welcome to FLAP Canada’s Bird Migration Tracker: an open window into the world of birds as they fly through the Great Lakes region. Like a pollution index or pollen count, the Bird Migration Tracker is an outreach tool designed to monitor bird migration traffic and to alert us when the concentration of birds in the region is at its highest. It is during these peak traffic periods when the Bird Migration Tracker alerts us to importance of turning off lights at night and applying Bird Safe® markers to windows during the day. If you encounter a dead or injured bird that has collided with a window, please make sure to report this collision by using the FLAP Mapper.

The weather forecast and wind map help predict when weather conditions are most favorable for bird migration. When weather conditions are suitable, the Nexrad radar system can capture bird migration in real time as they fly through the Great Lakes region. The Tracker is most useful during bird migration seasons: mid-March to June in the Spring and mid-August to November in the Fall.

The Wind and Weather Beneath Their Wings

Birds instinct to migrate is often influenced by sudden shifts in temperature, amount of available daylight and moon phases, and when strong tail winds are present. With steady south winds in the Spring and north winds in the Fall, songbirds will use less energy enabling them to travel greater distances during their migrations.

When birds are confronted with sudden precipitation and/or foggy conditions they fly at lower altitudes. They are known to land when approaching inclement weather as they can detect storms by sight, smell, sound, humidity and pressure. This is when lit buildings, communication towers and light beams directed into the night sky become a threat to their safety.

Tracking Bird Migration on Weather Radar

Radar technology allows us to experience the mystique of bird migration at night. It also serves as a useful tool for the study of bird migration patterns and behaviours, as well as alerting us to any changes in those patterns and behaviors.

FLAP Canada's Bird Migration Intensity Alert

Interpreting the Bird Migration Alert Index

How Radar Works

Radar is essentially a tracking system that is used to detect the location, speed, direction and altitude of an object. The two main components of a radar system include a transmitter that emits pulses of energy into the atmosphere at regular intervals, and a receiver that captures any reflected radar energy. Radar energy gets reflected when it “bumps” into a solid object in the atmosphere. The larger the solid object, the higher the value of the reflected energy; for example, a raindrop produces a higher reflected energy value than a unit of drizzle, and a bird produces a higher reflected energy value than an insect.

Radar operates in two modes: Clear Air Mode and Precipitation Mode. When there is no significant precipitation detected within the range of the radar, it is switched into Clear Air Mode. In Clear Air Mode, the radar’s antenna spins more slowly which dramatically increases the sensitivity and resolution of the radar. Bird, bat and insect migrations are detected using Clear Air Mode. The radar images of these migration echoes provide valuable information for biological research.

Radar Image of Bird Migration

This animated picture illustrates a series of radar images from a heavy night of bird migration through Toronto, Canada. The more you use the Bird Migration Tracker the easier it will be for you to make the distinction of what are birds vs. what is weather such as precipitation on the radar screen.

Step Outside and Experience Migration

On a clear night and when wind direction is favourable; we can see radar images of birds migrating through the Great Lakes region from sundown to sunup. These are ideal conditions as birds will be flying at high altitudes and therefore are less likely to be drawn into lit environments. It is on these nights we encourage you to step outside and listen to the countless distant peeps and chirps of birds overhead. If you look closely enough, you can even see the silhouettes of birds passing over the light of the moon. Tens of thousands of birds from dozens of species can be detected flying over our city as we sleep. The Bird Migration Tracker is designed to educate, inspire and perhaps motivate you to help protect these birds for future generations to come!

Enjoy using the Bird Migration Tracker, and by all means share your excitement with others. Be sure to check out FLAP Canada’s tweets with updates on what is happening to birds on the ground and in the air and how we are helping to prevent the loss of bird species.

Click here to visit the FLAP Bird Migration Tracker.