Autumn can be an amazing season for birding, but it can also be a very dangerous one for birds, whether they are year-round residents of the same area or if they are embarking on outstanding fall migrations. By recognizing the different threats birds face at this time of year, birders can work to make the season safer for all their feathered friends.

How Autumn Threatens Birds

Fall is a seaon of change, and those changes can be dangerous to birds, including…

• Loss of Food: While harvests may be bountiful, the seeds, nuts, and fruits of the season are not being renewed the longer autumn stretches, and birds have fewer food sources to rely on when they need more energy for travel.
• Rotten Food: Though birds may not care about the taste of their food, rotten windfall fruit can ferment and cause drunk-like effects for birds that indulge. Similarly, rotten spilled grain can harbor fungus that can be fatal to birds.
• Habitat Loss: Development projects that may have eliminated habitat during the summer months means less habitat is available for birds to use in the autumn when they are on the move through unfamiliar territories.
• Shelter Loss: Many people prune trees or rake leaves in autumn, but this can deprive birds of essential shelter just as the weather is changing and they need shelter the most.
• Landmark Changes: Birds use a variety of geographical landmarks as part of their migration navigation. When landmarks are changed, such as new construction or changes to agricultural fields, birds can get disoriented and lost.

• Light: Changing light levels and both the moon and stars aid in bird migration. Severe light pollution along migration flyways can disorient birds and turn them away from where they need to go.
• Halloween Decorations: Filmy cobwebs are popular Halloween decorations, but they can become tangle hazards for birds when they are strung across trees and shrubbery where birds might roost in autumn.
• Storms: Sudden autumn storms can be severe with winds, rain, and even blizzards in northern areas that can be devastating to birds. Not only can birds get disoriented, but such storms can be fatal if the birds aren’t able to find adequate shelter.
• Predators: Just as birds change their diets to get ready for migration and cache food for the coming winter, other predators may be hunting more frequently as they build up body fat reserves, and birds can be a prey target in autumn.
• Glass: As birds are migrating, reflections of nearby trees and shrubs in glass panes create the illusion of more habitat when really birds will hit the glass, making them more vulnerable to nearby predators or causing fatal injuries.

How You Can Help

Despite the threats birds face in fall, it’s easy for birders to take steps to help them overcome each hazard and survive the season without difficulty.

• Keep feeders full with high-fat, calorie-dense foods like suet, nyjer, black oil sunflower seed, nuts, and nectar to provide rich and reliable food sources throughout the season.
• Let flowers go to seed and leave some fruits and berries on bushes for birds to take advantage of in autumn. They will remember the resources and return each year for the bounty.
• When windfall fruit begins to rot, clean it up and dispose of it properly. Even as weather gets cooler, feeders should still be kept clean to be safe for hungry birds.
• Avoid pruning in autumn if at all possible, or use pruned branches to create a brush pile so birds and other wildlife have shelter through the fall and winter months.
• Leave those leaves! Minimize raking and let birds scratch through leaf litter in search of seeds, nuts, insects, grubs, and other choice tidbits.

• Turn off exterior lights on porches, fencelines, decks, garages, and outbuildings, and shield strong indoor lights by closing curtains or shades so birds can navigate more easily in the dark.
• Support local “lights out” programs in metropolitan and suburban areas, particularly along migration corridors, so birds aren’t disoriented and exhausted by light pollution.
• Do not use outdoor cobweb or similar decorations that could present tangle hazards for birds, and minimize how long any decorations may be up and obscuring valuable shelter.
• Put up roost boxes for fall and winter use, or convert bird houses for off-season use after nesting birds have raised their broods and moved along.
• Always keep cats indoors and ensure birds have adequate shelter to hide from any hungry predators, including raccoons and similar wildlife that might be hungry in autumn.
• Use decals, reflective tape, string, or other obstructions to break up glass reflections so birds can more easily see and avoid the hazardous surfaces.

Autumn is a beautiful season for birding, but the threats of the season can be very ugly to birds. By understanding these threats, we can all more easily take steps to keep birds safe and enjoy every day of autumn.