The end of April, and a week of really fine weather. The last winter troglodytes were coaxed out of their burrows and found their way to the beaches with frisbees, dogs, picnics, and sunscreen. Temperatures were reported to be in the 60s in some parts of town - practically tropical.
It wasn't that warm near the glacier, but the sunshine made for comfortable basking at Photo Point, while we watched whatever was going on near that corner of the lake. Tiny avalanches on Mt. Bullard created periodic background roars that seemed way out of proportion to the amount of snow released.
Five mountain goats foraged on the far side of Nugget Falls - two solos and a group of three, including a small one presumed to be last year's kid. Eventually they all disappeared into the alders, perhaps they got too hot in the sun.
A robin sang from a small cottonwood, while other robins foraged among the low plants on the sand flats nearby. A male harrier was hunting along the edge of the trees and over the flats, and his approach put the robins to flight. He also spooked up a greater yellowlegs that looped up over the lake, yelling its characteristic three-note call. The gulls perched on The Rock across the lake had claimed nest sites, but periodically sailed out in large white clouds over the water.
Pretty soon, the robins came streaming back and settled down to foraging again. Suddenly, about five of them zoomed in tight formation right over our heads. Four were clearly chasing the fifth bird very aggressively, but the transgression that prompted the chase was not apparent. While this was going on, a couple of American pipits flew in and walked over the sands.
A little later, near the lowest salmon-viewing platform, we found a pair of Barrow's goldeneye diving in the pond. These ducks eat a variety of invertebrates. We know they sometimes nest in the Rec Area and rear their broods on the beaver ponds. They commonly nest in tree cavities, as much as perhaps fifty feet up, producing clutches of 6-10 greenish eggs. Sometimes a second female lays her eggs in the cavity claimed by another bird, leaving her eggs to be tended by the "parasitized" nest owner. Incubation lasts a bit over a month. After incubation begins, the males leave and go off to molt.
Females do all the parental care, as in most ducks. Ducklings from nests high in a tree have an interesting entry into the world - their only choice is to flutter down to the ground, however far away it may be. This challenge is endured by other tree-nesting ducks and by some species of cliff-nesting sea birds. Fortunately, the ducklings are light and fluffy, and don't usually get hard landings. They make their way to a pond, where they are guarded by the female. They have many predators, of course, but some of them will eventually grow up. They take two years to reach maturity.
Although Barrow's goldneyes are basically tree cavity nesters, sometimes they nest in marmot burrows or crevices in cliffs, and they may even use old crow nests or mistletoe clumps up in conifer trees. Nest sites are often near ponds, but sometimes may be hundreds of yards away from water. In some areas, the availability of acceptable nest sites may limit the size of the population.
There were lots of willow catkins in bloom, presenting their pollen on knobby bristles just outside the fuzzy gray "pussywillow". We watched several beautiful bumblebees assiduously collecting pollen. Male willows often start flowering a little earlier than female trees, and so the earliest may miss the chance to father seeds.
Mary F. Willson is a retired professor of ecology.
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