Like so many others, I’ve spent more time this past year watching birds than I may ever have. Watching birds, whether in the wild or from your windows is the perfect socially-distanced, stay-close-to-home activity.

One of my favorite bird-watching spots is the Staghorn Sumac (Rhus typhina) tree outside my office window. The tree sits above the bird feeders so there is a constant coming and going of birds. The clusters of red, fuzzy berries formed this year still cling to the tree and are a source of food for winter birds. I knew this weedy-looking tree had wildlife benefits. But who specifically did it benefit, I wondered?

So I started a list of all the birds that visit the tree. I have 18 bird species on the list so far. I soon discovered it wasn’t enough to see a bird on the sumac and put it on the list. I wanted to know what they were doing there. Some, like the European House Sparrows were just perching there. Others, including Blue Jays, American Robins, European Starlings, and Northern Cardinals were perching there and eating the berries. So, my list became two — one list for eating and one list for perching. And the eating list took some work.

Evidence of an American Robin eating Sumac. Photo by Jeff Tome.

Some birds were put on the eating list very quickly. A flock of over a dozen American Robins moved in for an afternoon. Red berries were literally flying as they worked to fill their stomachs. Blue Jays sit in the tree for long moments, picking at the berries. Often, they get one in their mouth then tip their head up and look like they are working hard to swallow, their head and throat bouncing up and down a little. Perhaps this is what it looks like when a Blue Jay is storing something in their gular pouch — a spot in their upper throat used to carry food. Where they carry it to is another question.

Black-capped Chickadee is one that took time to get on the eating list. A common visitor at the bird feeders, it made sense that chickadees would also be common at the sumac that towered above. But when it came to eating the sumac berries, I couldn’t be sure. Chickadees hop around, quickly, almost frantically, from cluster to cluster pecking. It appeared like it was looking for something inside the cluster. But what? If I were an insect, perhaps a pupating larva, these clusters of berries would be a snug spot to curl up in for the winter. Fueled by curiosity, I went outside and pulled a cluster of berries apart. There were no insects inside but there was a lot of frass, otherwise known as insect poop. So perhaps the chickadee was looking for insects after all.

These detailed observations may seem to some like a frivolous exercise, or worse, a waste of time. But watching the birds at the sumac has caused me to think a lot about evidence. To support what we think is true, we need information. Facts. Proof. But how do we get it?

I started with a question and found the answers through my observations. I was curious as to what birds benefit from this tree. It wasn’t enough to see a bird in the tree and add it to the list of birds that use the tree. Birds will perch on so many things — telephone wires, roofs, sign posts — and there are so many other bushes and trees around, providing a place to perch hardly seemed like a critical service. But food was a critical support so I kept track of who was eating the berries. To add a bird to my eating list, I decided my evidence was seeing a berry in the bird’s mouth.

European Starling eating Staghorn Sumac berries. Photo by Jeff Tome.

Pecking at the clusters was not enough evidence to show the bird was eating it. Like the chickadee, the bird pecking at the berries could have been looking for insects, not berries for lunch. I’ve witnessed Downy Woodpeckers and Northern Flickers, both well-known insect eaters, do the same thing. Eventually, I saw all three eat berries. But at first, I wasn’t sure. I needed evidence.

Sometimes we accept something as fact and then learn more, causing us to adjust what we know to be true. White-breasted Nuthatch is on my sumac list. At first, I added it to the eating list because that’s what I thought I saw. It was sitting just next to a cluster of berries pecking at something by its feet. I assumed it was a berry but couldn’t tell. However, it flew away and came back with a safflower seed from the bird feeder. It placed it on the same spot — a divot where there once was a leaf or branch — and used its beak to open the shell of the seed. Since then, I have watched nuthatches repeat that behavior in different places along the tree. They seem to prefer, to the point where two birds will fight over it, a spot in the center of the tree where two large branches veer off. But I have not seen them eat berries.

There are things we want to be true but there is little evidence to support it. I really wanted to put Eastern Phoebe and Gray Catbirds on the eating list. Mostly insect eaters, they also eat fruits and seeds. But I never saw them eat a berry. But does it mean that because I never saw it, it doesn’t happen?

Our knowing is not limited to only what we witness. Humans have been sharing their experiences since, well, we’ve been human. There is a great body of knowledge available to us. There are things that we, as people, have accepted as true. My very ability to identify and put names to the birds I am watching is due to this accepted way of making sense of the world. I have looked up the eating habits of these two birds.

But to use these sources of information, we must trust them. What I trust may be different than what someone else trusts. How often do we think about that trust? Is there evidence to support what the source claims? Is that evidence strong or weak? And once we accept a source as trustworthy, is that true forever or do we need to reevaluate all the time?

Our discoveries often lead to more questions than when we started. For example, perhaps my observations of phoebes are related to the condition of the berries. All of my additions to the eating list have been entered between the months of December through March so far. Are sumac berries like turnips and other winter vegetables? Do they taste better after a hard frost? At that point, phoebes and catbirds are long gone for winter grounds much warmer than here.

I would be foolish to admit I know all there is to know even about this simple topic. So, I have learned to use the language of uncertainty. I ask myself, “How do I know this is true?” I try to clarify my opinion, my ideas, and the facts by saying “I think” or “I know.” Saying “I don’t know” is not as hard as it once was. Or “I don’t know… yet,” leaving room for future growth and discovery. As I write this, I just watched a White-breasted Nuthatch hide a safflower seed inside the berry cluster. Is that what other birds are looking for? Perhaps. One thing I find to be true is the more you know, the more you don’t know. And if you think you know all the answers, maybe you just haven’t looked at something enough.

Audubon Community Nature Center builds and nurtures connections between people and nature. ACNC is located just east of Route 62 between Warren and Jamestown. The trails are still open from dawn to dusk as is Liberty, the Bald Eagle. The Nature Center is partially open, including restrooms, the Blue Heron Gift Shop, and some exhibits. More information can be found online at or by calling (716) 569-2345.

Katie Finch is a Nature Educator at ACNC.