The final week of CHIP spring migration monitoring has brought some varied weather to the station. The last of the neotropical migrants have been trickling through and many local breeding species began nest building and courting. Captures have slowed down greatly, with days averaging only 20 birds. Although the majority of birds caught are our common breeders such as Yellow Warblers, Least Flycatchers, American Robins and White-crowned Sparrows, we have been fortunate to capture some less common local species, such as this male Lazuli Bunting. Photos do little justice to their aqua-marine blue plumage, which is unlike any other species in North America.
Another treat was this female Black-and-white Warbler! This species migrates readily through CHIP, although we rarely catch many during spring. These birds are easily identified by their contrasting black and white stripes, as well as their nuthatch-like creeping on branches and trees.
With Yellow Warblers being one of the most common species around the station, yellow is a prevalent color flittering among the trees! This week brought the arrival of another bright bird, the American Goldfinch! These beautiful black and yellow birds can be seen and heard all around CHIP, and most are seen chasing or flocking above in the trees. Note the molt limit in the greater covers and compare the left wing tertials to the right.
Although the nets are sized to target smaller docile passerines for banding at CHIP, occasionally larger, more aggressive species are captured. A surprise was awaiting us in the net, as a Common Grackle had managed to stay in the net long enough for extraction. These big and powerful blackbirds produce beautiful iridescence in their feathers, and contrast nicely with their black body plumage.
We were fortunate enough to catch two Pine Siskins within the same net run which allowed us to compare the differences in flight feathers for aging purposes. The bird on the left (second year) shows lighter coloration on the primaries, secondaries, and tertials, as well as lacks the white edging that is present on the bird on the right (after second year).
Finally, our quiz bird for the period. A nest we have kept watch on over the spring has produced some fledglings!