White-throated Sparrow

Here's a White-throated Sparrow I met last April. When I saw this picture this morning, my 1st thought was that April might not be a good time to find these birds in New Jersey:

  1. Although there are a lot of these birds that spend the winter in New Jersey, but they (mostly) migrate further north to breed.
  2. Some of our White-throated Sparrows had probably already migrated north, and even if all of them hadn't done so, they ought to be less frequently spotted by now.
So I was a little surprised to see that sightings of these sparrows actually peaks in April. (This link demonstrates the idea.) What's going on? I think I know:
  1. Some (maybe even most) of the White-throated Sparrows that wintered here probably have migrated north by this time.
  2. But even more White-throated Sparrows who spent the winter further south are probably migrating through New Jersey this time of the year, more than making up for the losses of our winter residents.
  3. Migrating birds probably don't know all the best places to eat and hide, so they have to move around more, making it more likely that they're spotted.
Anyway, that's my theory. 😀
April 20, 2023 at the Plainsboro Preserve
Photo 272674186, (c) jpviolette, some rights reserved (CC BY-NC)


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