May 22 is the earliest date on which I have seen the young, and by August 1 they are full grown. At this time they are remarkably tame, allowing an approach to within a few yards and then, if alarmed, swimming to the middle of the lake, rather than taking wing. This fearlessness is characteristic until the shooting season opens in September, when they soon become wary. At this time, the birds rise from the water as one approaches, but almost invariably circle about the lake several times and then fly towards anyone standing on the shore, thus affording an easy Shot. By the last week in October, when the common Golden-eye, Redhead and Scaups are returning from the north, the last of the Barrow Golden-eyes have left.
The feeding habits of the two species of Golden-eye are identical. Both species are greatly attracted by the small crawfish lurking under large stones in shallow water. While hunting these shellfish, the ducks work rapidly along the shore, diving every few minutes, to probe under the edges of the large stones. They invariably try to submerge even if the water is not deep enough to cover their backs, and I have never seen them dipping as Redheads and Seaups frequently do. One can follow the Golden-eye's movements as it encircles the large stones, by the commotion on the surface and by frequent glimpses of the duck's back. In shallow water, the birds remain below frown fifteen to twenty seconds, the crawfish being brought to the surface to be swallowed. By the end of winter the feathers on the forehead are generally worn off, through much rubbing against stones in this manner of foraging. When feeding in deep water, over the beds of Potamogeton they stay in the same place until satisfied. In such places the small snails and erustaeea that attach themselves to the atems of Potamogeton form their chief food, but little vegetable matter being taken beyond what is eaten with the shells. The small shellfish are swallowed while the birds are below the surface of the water, unlike the procedure followed with the larger crawfish. Their stay under water is of fairly uniform duration, ranging from fifty to fifty-five seconds. At the beginning of the dive the tail is raised and spread-to its full extent.
As far as I have been able to observe, there is no difference in the flight of the two species of Golden-eye. Both have the same clumsy way of rising, and of flying close to the surface before attaining any speed; once under way they travel swiftly, and one's attention is held by the distinctive, musical whistle of their wings. Both the Barrow Golden-eye and the American Golden-eye are less gregarious than others of our ducks with the exception of the mergansers. I have never seen the Barrow Golden-eye in large flocks except in the mating season. When feeding, two or three birds together are the rule, and five or six the maximum number noted. It is difficult to distinguish the young of our two species of Golden-eye. The only constant difference is in the shape of the bill. In comparison with americana the bill of islandica is shorter, deeper at the base and more sharply narrowing towards the tip. The nail is wider at the front, projects farther over the tip of the bill, and is slightly raised above the bill, forming a noticeable lump. These differences arc more apparent in the freshly killed birds than they are in dried study specimens. The black bar across the speculum, generally described as a diagnostic feature, is of little use in identifying young birds. I have seen young males of islandica with immaculate speculums, and several of americana with noticeable bars crossing this tract.
Okanagan Landing, Brilish Columbia, Canada, December 5, 1917.
