Bad Photos of Ugly Birds, Part III

[I should note that a good portion of the Bobolink section of "Bad Photos of Ugly Birds" series was originally written for an article that appeared in a shorter version in Black Swamp Bird Observatory's publication Dendroica sometime around 2006 or 2007. Here is a list of sources that I've taken some of the information from for these posts. All of these are available via libraries or the internet:

Sources:

Birds of the Toledo Area. Ohio Biological Survey. Columbus, Ohio.

The Bobolink. Fall 2004 issue.

Campbell, Lou. 1968. Birds of the Toledo Area. The Toledo Blade Company. Toledo, Ohio.

Johnsgard, Paul. A. 2001. Prairie Birds: Fragile Splendor on the Great Plains. University Press of Kansas. Lawrence, Kansas.

Martin, S. G., and T. A. Gavin. 1995. Bobolink (Dolichonyx oryzivorus). In The Birds of North America, No. 176 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists’ Union, Washington, D.C. (also available via subscription to The Birds of North America, online version).

Peterjohn, Bruce, G. 2001. The Birds of Ohio. The Wooster Book Company. Wooster, Ohio.

Pettingill, Olin Sewall, Jr. 1983. Winter of the Bobolink. Audubon 85(3): 102–109.

Sibley, David, Chris Elphick, John B. Dunning, Jr. 2001. The Sibley Guide to Bird Life and Behavior. Alfred E. Knopf. New York.]

Part III:

By mid-July, molting adult Bobolinks take on a motley, harlequin-like appearance and are a crazy quilt of yellow pin feathers, fresh buff-yellows, faded browns and blacks, and speckled whites. Female molt is similar, though it doesn’t seem at a casual glance to be as dramatic as that of males, given that alternate-plumaged females are more subdued in color to begin with.

Bobolinks actually never entirely lose their tails, but they do molt their tail feathers in rapid succession, leaving them with stubby tails until the replacement feathers are fully grown. The female in the photo below is replacing her middle rects:

(Adult female Bobolink. 17 July 2004)

The next photos are of birds that are often called juveniles by observers. But they’re both adults.

The Bobolink in the top photo shows fresh tertials and wings, though the tail is yet to grow out fully. The lower bird has fresh wings, but, again, the tail feathers have not fully grown out. Either birds could be confused for "tail-less" hatch year birds, fresh out of the nest. Both birds were photographed on 25 July 2004.

During the molting period, Bobolinks form mixed flocks of males, females, and young birds. Toward the end of the molting process in early-August, these flocks become very “flighty” and spend a great deal of time flying to and from different parts of the field, their tell-tale metallic “pink-pink” calls serving as the best way to track them as they bound here and there through the grass. While Bobolinks in juvenal plumage are just as distinctive in their own way as adult male and female Bobolinks in alternate or breeding plumage, juvenile birds molt into their first basic plumage shortly after leaving the nest. The gorgeous, lemon-yellow underparts, cinnamon stippled flanks and upper breast, and scalloped upperparts of juvenile Bobolinks are rather quickly exchanged for a plumage that is very similar to the basic or “nonbreeding” adult plumage. (Photos of Bobolinks in true juvenal plumage are hard to come by).

(Hatch-year Bobolink in juvenal plumage. It will soon begin a molt of its own, into a more "adult-like" basic or "nonbreeding" plumage. 3 July 2004)

Once they molt, it is difficult to separate hatch-year birds from adults when all the birds are in basic plumage. Though in the hand, it is rather easy to do so, in large part because hatch-year Bobolinks in basic plumage retain their juvenal wing and tail feathers, whereas adults go through a complete molt and have fresh wings and tails in late-summer and fall.

Adult Bobolink near the completion of his or her molt, 3 August 2004. The tail feathers are still a little uneven.

Part IV and conclusion to come . . .