Submarine Mergansers of the Sierra
- This past weekend found me back in the mountains, in the Echo Lake area above and to the West of South Lake Tahoe. The Sierra is always a treat this time of year. The weather is crisp, the aspen leaves are yellow, and the mushrooms have a last gasp of growth before the snows fall. But it takes rain to make mushrooms, and the duff underfoot was potato chip crunchy. Normally I can rely upon the local birds to fill in the gap, but somehow even they were reluctant to cooperate.
After trudging through the woods and finding next to nothing fungal, it was with relief that I spotted a foraging dipper, on the placid waters of the upper Truckee River where it flowed under Hwy. 50. I had never seen one forage while surface swimming before. This bird paddled along the surface of the water, with his head submerged, as he flowed along with the current. He soon tired of this, and dipped along the rocky shore, as he picked at tidbits, and flashed his white-feathered eyelids. I watched him from my vantage point on the opposite bank, and he paid me no mind. Or maybe all that dip and flash was for my benefit! While I watched the dipper, a kingfisher rattled past, just to let me know that there were at least two birds in the Sierra that day.
Giving up on mushrooms, my husband David and I drove down to Taylor Creek in South Lake Tahoe, to view the spawning, land-locked Kokanee salmon. Despite the hordes of fish-watching people that crowded the bridge, and streams of marathon runners that slipped through the crowd (nothing like the solitude of the mountains!), there was a small flock of pale orange-crested common mergansers just below us. These birds were unusually tolerant of a close human presence. Since the salmon seemed almost as large as the birds, I found it difficult to believe that the mergansers were hoping for a super-sized meal. Surely they were after smaller prey? A half dozen of these fish-loving ducks floated placidly on the water, while the red and green bodies of the salmon clustered beneath them.
Suddenly, the mergansers started swimming like maniacs, plowing along just under the surface, and making wakes like a submarine, with their bodies and heads submerged but still afloat. It was quite a spectacle, but none of the birds seemed to actually catch anything. Were they just displaying to each other? I was still convinced that they were after smaller prey, since the creek is also full of minnows and sunfish.
I crept along the stream-bank, and fought my way through tangles of willow and aspen, to try and get a closer look and a video of their odd behavior. As I stood half-concealed along the bank, up popped a merganser with a fat salmon in his bill! It was at least half of the bird’s length, but down the hatch it went. With prey this size, there was no need for a second fish. Out of the water he came, to sit upon a log and begin the laborious process of digestion. Although the merganser made mincemeat of my prey-size theory, what fun to watch the seemingly impossible made possible.