Hey guys, welcome back! We got ourselves another warbler today, one that can be very difficult to ID. First off, yes, this little guy is, in fact, a warbler. I know it doesn’t look like one, but trust me, they aren’t all tiny (mostly)yellow birds that flit about high in trees! As it’s name suggests, this warbler actually looks similar to a thrush, with its brown color and heavily streaked belly. The Louisiana Waterthrush’s habits aren’t un-similar to those of some shorebirds, particularly Solitary or Spotted Sandpipers.
Now, you might be thinking “hey, if most warblers are brightly colored birds that don’t act like sandpipers, how is this bird so hard to ID?” Well, there’s another waterthrush, the Northern Waterthrush, and as you can see here, they’re damn near identical. There are a couple tricks to help out though. These tricks, however, are generalities. Each individual can vary slightly, making it very tough. The Louisiana typically has a larger beak (but the odds of being able to tell this in the field are essentially zero, so let’s skip this one), whiter “eyebrow”, pinker legs, and less spots on the throat (directly under the bill.) The “eyebrow” trick is the one most people look to first, but the difference between “slightly off-white” and “light yellow” can be difficult at best! ID is trickier during migration, as the two share similar habitats. On their breeding grounds, however, they don’t overlap as much, with Louisiana Waterthrushes preferring faster moving streams to slow, boggy water. They also both dip their tails, so in this case that trait isn’t a great indicator of what you’re looking at.
The waterthrush debate is particularly hot in Central Park I’ve witnessed very experienced birders come close to full on argument over which waterthrush they were looking at! I always kept my opinions to myself, unless asked, and even then, I wouldn’t speak in absolutes for fear of sparking more… heated debates. The Waterthrush debate isn’t so hot in Canada, as the Northern breeds up there in summer, while the Louisiana rarely makes it that far north.
Well, it’s summer, and around here that means lots and lots of swallows. Come back next time when we get to our first swallow species, the Northern Rough-winged Swallow! (what a mouthful) See you all then!