Mergansers, the Ducks with the Wrong Beak
Okay, so this is the last duck lesson before we move into raptors, and I saved mergansers for the end on purpose, because they're the one that makes people say "wait, that's a duck?"
They don't look like they belong in the duck family at all. Everything we've talked about so far, the mallards, the teal, the goldeneye and bufflehead, they all have that flat, wide duck bill you'd draw if somebody handed you a crayon and said "draw a duck." Mergansers don't. They have a long, thin, serrated bill, almost like a saw, and it looks borrowed off some other bird entirely. That's the whole lesson today. Wrong beak, right duck.
Why the beak is different
Ducks eat different things depending on the species, and the bill tells you how. The dabblers have those wide flat bills for straining plants and little bits of food out of shallow water. The divers we talked about last time have shorter, sturdier bills for cracking open mollusks.
Mergansers are fish eaters, mostly. That serrated bill is built to grab a slippery fish and not let go, kind of like a bread knife with a job to do. Once you know that, the bill stops looking weird and starts making sense. It's not a design flaw. It's a different tool for a different meal.
What to look for on the water
Three mergansers you're likely to see around here in winter:
Common merganser. The big one. Males are mostly white with a dark green head that can look black in bad light, which out on the lake at 8am is most of the time, so don't lean on color. Females and immature birds have a rusty, ragged-looking head, almost like they've got bad hair, with a sharp line where the rust color meets the white throat. That head shape and that line are what I look for before I even think about color.
Hooded merganser. Smaller, and the male has this fan-shaped white patch on his head that he can raise or flatten like a little hood, hence the name. When it's up it's unmistakable. When it's down he looks almost plain, so give him a minute, he'll probably show it off eventually.
Red-breasted merganser. Less common on our local water but you'll sometimes get one. Shaggier crest than the common merganser, looks a little wild-haired even when it's not trying to impress anybody.
Behavior-wise, watch how they move on the water. Mergansers dive a lot, like the goldeneye and bufflehead, but they also tend to swim low with just the head and neck up, kind of stretched out and alert-looking, scanning. It's a different posture than a mallard sitting high and round on the surface. Shape and posture again, same as always. I keep coming back to it because it keeps being true.
A practical thing to try at home
You don't need the lake for this part. Pull up photos of a mallard bill and a merganser bill side by side, doesn't matter where, library computer, your phone, whatever you've got. Just look at the shape for a minute before you ever go looking for the bird itself. It sounds like a small thing but it changes what your eye catches out on the water. I did this with a stack of photocopies from the library that first winter, sitting at the kitchen table, and it made an actual difference the next time out.
That's the opinion I'll state plainly here: learn shape before you worry about color, every single time, because the light out there lies to you constantly and the shape never does.
A quick aside about gear, since we're near the end of the course
I still tell people not to overthink binoculars. Mine were on sale at the sporting goods store four years ago and they've been fine this whole time. Speaking of which, my first winter out with a pair, I had them on completely the wrong setting the entire first hour and just figured that was how blurry birds were supposed to look through binoculars. Alan finally took a turn looking through them and started laughing at me. A stranger walking by on the trail saw what was going on and showed me the little focus dial, no judgment at all, just walked over and fixed my life in about four seconds. That's birding for you. People are kind about the dumb stuff. If your binoculars seem broken, they're probably not. Check the dial before you assume the worst.
One real caution here, nothing dramatic: if you're out on the ice edge trying to get a closer look at diving ducks, mind your footing. The shoreline ice this time of year is not always as solid as it looks, and a merganser is not worth wet boots or worse. Stay back, let the binoculars do the getting closer.
Before next time
See if you can find a merganser and just watch the bill do its thing for a minute before you worry about naming the species. Next time we're leaving the water behind and starting on raptors, which is where I get a little bit obsessed, so come rested.