A large flock of double-crested cormorants has been sojourning on the Bear River at the refuge this fall. While cormorants nest there and are a common sight, the numbers — hundreds — that amassed on the river in one flock are unusual in a state as arid as Utah. Fellow refuge volunteers Lee Shirley and Les Talbot also reported seeing this large flock and the birds’ unusual behavior days after I did.?Cormorants are large, dark water birds known for swimming with only their serpentine heads and necks above the water’s surface, and for perching on partly submerged logs with wings spread. They have a primordial look with glittering, reptilian emerald eyes against bare orange facial skin, black feathers in the adults, and lethal, hooked bills.?The flock was fishing at one of the big river bends along the road eight miles west of the visitor’s center. As the distant flock proceeded downstream toward my position, it became evident that the pale necks and long heads were that of mostly juvenile double-crested cormorants.?The few adults in the crowd stood out strongly due to their black necks, and one adult still showed the breeding plumage of twin crests on either side of its head when it surfaced and shook water from its feathers. I estimated that the flock numbered 150 to 200 birds.?They were systematic in their progress downstream. The birds remained tightly together and zigzagged across the river, which is quite wide and slow at this spot so close to the mouth. As they cut across the current methodically, each bird dived in turn so the whole flock was moving at once. Each surfaced, often with a small, silvery fish, tilted its head and choked down the catch, then swam forward and dived again.?The fish that the flock was catching were relatively small — just three to five inches long. But cormorants are capable of much bigger meals, fish up to 15 inches. Their expandable throat pouches and unique jaw hinging allow them to take in positively porcine-sized portions.?When the flock approached the bank, some signal or leaders’ initiative caused it to change course slowly toward the opposite side, and they cut diagonally downstream again, remaining tightly packed while continuing to fish. They had laid out a dragnet so effective that their systematic plundering of the river’s fish was yielding plenty for all. It didn’t matter that the water was brown and murky; feeding for this flock looked as easy as a herd of swine rooting in a trough.?The mass became audible as the flock closed on the embankment near me. The constant diving coalesced into a sound like roiling, splashy current, and individual birds were calling that guttural, snorty sound for which cormorants are known: The pig grunt.?I do expect to hear songs from birds; I expect to hear chirps, tweets, trills, warbles and hoots. But I don’t expect to hear pig grunts, leading me to believe that a herd of winged pigs was fishing in the Bear River.?The herd became somewhat dispersed during the next trip across and then they began to take off, flapping hard and double-footing the water’s surface to gain lift. That gave me the opportunity to count them. I kept up pretty well with the pig pile until I reached 170, then I realized that that many more must have come from upstream while I was distracted by the grunting. The remaining flock boiled past me and was easily more than I had already tallied, bringing the total to perhaps 400 birds.?They continued downriver flying just over the water. I followed them for a mile through the big curve near the Bear River Club. There, the biomass landed on the water and many birds extended their wings as if they were drying them in typical cormorant fashion. I’ve never seen that, either: Cormorants drying their wings while floating on the water, rather than while perched. I guess that’s another behavioral characteristic that’s not impossible for this bird, like when pigs fly.?

Kristin Purdy can be reached at gobirding@comcast.net.