Lowest Bird Abundance at FeederWatch Sites in Ten Years

We often receive inquiries from participants asking, “where have all the birds gone?” and telling us that bird counts seem lower than in the past. Typically, these observations are localized and don’t reflect a wider trend, but in the 2023-24 FeederWatch season, average counts across the board were lower than in the recent past. That season the average number of birds per checklist was 37 individuals. For many participants, that is a lot of birds! But comparing that average to the FeederWatch average over the previous 10 years provides perspective. The 37 birds per checklist average was the lowest average since at least 2013.

Exactly why average bird counts were lower isn’t clear. The averages don’t control for the amount of time participants watched their sites or the experience of the participants this season compared to past seasons, which could account for at least some of the differences. An unseasonably mild winter in many parts of the U.S. and Canada may have allowed many birds to find natural food more easily, for example. Nevertheless, the lower counts could indicate that birds are declining broadly, which would be a worrying pattern.

Bird populations normally fluctuate from one season to the next and from one year to the next. Researchers have determined that the number of birds in North America has declined by nearly 30% in the last 50 years (read article from Autumn 2019 Living Bird), but for feeder birds, which are doing better overall than non-feeder birds, the declines have been gradual. If you are seeing a sudden, dramatic drop in bird numbers, most likely the cause is either local or seasonal. Although it’s impossible for us to know the cause of each specific increase and decline, there are several common causes for bird population fluctuations.

• The most common cause for a dramatic drop in all bird species at a feeder is the arrival of a predator, such as a hawk (often impossible to see) or a cat.
• Habitat changes frequently affect bird numbers. If there has been any change in your neighborhood–such as trees being cut down, new houses being built, or different crops being planted on nearby fields–that could be the reason you are seeing more or less birds.
• Natural food supplies–such as pinecones, berries, seeds, and insects–fluctuate from year to year, causing birds to shift ranges to take advantage of food surpluses or to compensate for food shortages.
• Weather fluctuations often cause birds to shift ranges, especially in winter, and in mild conditions birds often find plenty of natural foods that they choose over what’s available at feeders.
• Seed freshness can impact how many birds come to feeders. Seed allowed to stay in a feeder for more than a week can grow stale or moldy, especially in warm, damp conditions. Be sure to empty, clean, and refill feeders frequently. And some seeds, like nyjer seed, grow stale quickly even when kept dry. Avoid using seed that’s more than a year old.

To see what birds FeederWatch participants are reporting in your region or to see trend maps for different species based on FeederWatch reports, visit the Explore section of our web site.