Can hummingbirds remember the people who feed them?

Hummingbirds can remember the people who feed them. Is this possible?

Alexander Skutch, who has conducted decades of bird research in Costa Rica, wrote in his book “The Life of the Hummingbird” that after years of close observation, he believes that hummingbirds indeed can remember the people who feed them. When a hummingbird comes to your window in the spring and looks inside as if expecting you to feed it, it’s easy to think that this is the same individual you fed last summer. It very well might be, but without marking the individuals, we can’t be entirely sure.

Systematically studying hummingbirds, which are tiny birds, is more challenging than studying larger birds because only a few people are certified to band hummingbirds, and the bands suitable for their size are so small that they must be recaptured to read the information. Marking hummingbirds with colored markers might affect how other hummingbirds react to the marked individual, interfering with their normal social interactions and behaviors, and currently, there are no definitive studies on this. So, although our guess might be correct, it has not yet been scientifically proven.