A Bird’s Point of View: Fall Migration

Bird perched on a shrub branch.

Birds Have a Lot to Endure

The end of summer brings comforting, familiar feelings like the vibrant colours of autumn leaves, the sweet smell of pumpkin treats and crisp, dewy fall mornings.

While this may be so for humans, for a migratory bird, nothing could be further from the truth! The fall season is a very busy time filled with stress and danger. Many breeding birds in the Credit River Watershed are migratory, meaning they spend the winter in the United States, Mexico or even Central and South America.

Preparing for Migration

Before a bird’s migration journey begins, it must replace its old feathers with new ones, a process known as molting. Feathers are non-living tissue, like our fingernails and must be replaced when they get too worn or damaged. Molting is an exhaustive and stressful process, however birds must molt their feathers to ensure they will be strong enough for the long trip south. The molting process can take several weeks.

In late summer or early fall, American Goldfinches undergoing molt have a much scruffier appearance. Photo credit: Rodney Campbell, Flickr CreativeCommons

Risks During Migration

For small birds weighing only a few grams such as bay-breasted warbler, ruby-crowned kinglet and winter wren, the long flight to their winter retreat is difficult enough without the additional risks associated with predators, buildings and extreme weather.

Birds are particularly susceptible during migration. Two of the leading causes of bird mortality in Canada are:

  • Predation from introduced predators, such as house cats.
  • Collisions with building windows.

Additional factors such as habitat loss along migration routes and extreme weather events further worsen the challenges faced by migratory birds.

Once a bird arrives safely on its wintering grounds, it must secure a territory to acquire food and avoid local predators, such as snakes and even monkeys.

Bird perched on tree branch.
A bay-breasted warbler foraging in a hemlock tree during fall migration. Photo credit: Zach Kahn

How You Can Help Migratory Birds

Here are some simple things you can do to help migratory birds:

  • Turn your lights off at night during peak migration periods, including September through November and May through June. Birds are attracted to and disoriented by light. By turning off your lights, it helps birds to safely proceed with their migratory journeys.
  • Apply visual markers on your windows to lower the chances of window strikes.
  • Leave house cats and other pets, indoors or keep them on a leash when outdoors.
  • Create habitats for migrating birds in your yard by planting trees and/or install habitat structures .
Drawings from a marker on a window.
Window markers can be bird collision tape, decals and even unique drawings like this one… Benthics!

When you see a bird this fall, stop and take a moment to think about its journey. It’s amazing what such small animals are capable of! Learn more about birding in the Credit River Watershed.

Do you have questions about birds? Connect with us on Facebook, Twitter and LinkedIn.

By Zachary Kahn, Specialist, Watershed Monitoring

Comments (3)

  1. When do hummingbirds migrate south and when do they return to our area? Maybe the hot weather has changed their habits but they seem to have disappeared sometime in August this year. Also, the same with the orioles.???

    1. Credit Valley Conservation

      Hi Roy, typically, Ruby-throated hummingbirds and both Oriole species (Baltimore and Orchard) begin arriving in southern Ontario in early-May. Hummingbirds begin migrating south in August and are usually gone by early-October, while Orioles also begin leaving in August but are usually gone by early-September. The exact timing can change slightly year to year, and there are always a few early and late individuals in each season!

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