anonsally: lies:anonsally:Okay, @lies, I have another birdwatching puzzle for you! Today I went for…




Okay, @lies, I have another birdwatching puzzle for you! Today I went for a little walk in Tilden Regional Park with my parents. At one point I saw something flitting around from branch to branch in the bushes. With some patience, I managed to get a better look–at first it just seemed to be tiny, brown, and fluffy, but then I saw that it had some yellow on it–the face was yellow, just around the beak (the beak was orange) and there might’ve been a little yellow on the wings. It was visited and possibly fed by a yellower bird with a black cap who I didn’t get as good a look at. I think it might have been a fledgling Wilson’s warbler being fed by a parent? It had the look of a juvenile bird–still some downy bits. But I don’t think I’d ever seen a Wilson’s warbler in person before, and I’m not confident about this. Thoughts?

Circumstantial evidence: someone else on eBird did see Wilson’s warblers in that park today (on the other hand, it’s a very large park so they might not have been in that part of it). Also, I don’t think it was a lesser goldfinch (that being the other yellow bird with a black cap that I’m familiar with), because I see those all the time and I think I would’ve recognised it, plus the beak seemed too thin and the pictures of juvenile lesser goldfinches on the internet looked really different from this one.

Yeah, I think you’ve got it: a fledgling Wilson’s Warbler being visited and fed by its parent. There are a lot of juvenile birds around right now, and they can be tricky to identify due to their less-distinctive and less-often-seen plumages. But a distinctive-looking parent visiting them is usually a giveaway, and even seen briefly the other bird you describe seems very likely to be a Wilson’s warbler.

I’m not positive, but I think Tilden Regional Park might be named after Bill Tilden, the late entomologist who wrote a much-cited study on the insect associates of coyote brush. I’d like to visit it some day, not only to see the birds but also to check out the galls and assorted other bugs on the coyote brush there.

More about Tilden is in this article:

Yay! Thank you for the sanity check. I had never seen a juvenile warbler of any sort (at least not that I knew of at the time) or a Wilson’s warbler of any age, so that’s kind of exciting!

Tilden Regional Park is actually named after Charles Lee Tilden, who was a Bay Area attorney/businessman who helped create, and served on the board of directors of, the East Bay Regional Park District around the 1930s. I wonder if he is related to the entomologist?

Good to know that it’s a different Tilden. I guess Bill is more important to me, but not necessarily to the people who name parks.

Reposted from

Leave a Reply

You must be logged in to post a comment.