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Status: Population size: 22 million Photo by Cornell Laboratory of Ornithology.

Dickcissel
(Spiza americana)

This species was on the 2002 WatchList, but is not on the 2007 WatchList. Please refer to http://web1.audubon.org/science/species/watchlist/techReport.php for information on the 2007 WatchList.

Named for the distinctive, incessant song of males, Dickcissel is a characteristic bird of the farmlands of the Great Plains. The exact location of this bird's breeding efforts can be very erratic from year to year, as it appears to wander somewhat in response to rainfall and habitat conditions. During the winter, Dickcissels gather in huge flocks on the llanos of Venezuela, where they feed on rice and sorghum. Dickcissel's reputation as an agricultural pest in Venezuela, combined with its propensity for forming enormous foraging and roosting flocks there, leaves it very susceptible to poisoning and other eradication efforts.

Identification
Dickcissel is a stocky, sparrow-sized bird with a heavy bill and a short tail. The adult male has a gray head with a yellow eyebrow, a pale crescent below the eye, and a white chin and mustache. The center of the breast is lemon-yellow, which contrasts sharply with a black V on the upper chest. The upperparts are brown, with black stripes on the back and a rusty patch on the shoulder. The bill is blue-gray. The female has similar patterns, but without the bright yellow and black of the male. Females and immatures can resemble House Sparrows, but have a sharply-defined ear patch, a blue-gray bill, and some streaking on the flanks. Female Bobolinks have striped crowns and spiky tails.

Distribution and Population Trends
Although this species once nested as far east as the Atlantic Coast, Dickcissel is now primarily a bird of the American Midwest. It can be found breeding from northern Texas and Louisiana northward through the Great Plains to southern Manitoba and Saskatchewan. The species' typical breeding range also stretches eastward to Georgia, Tennessee, Kentucky, Ohio, and southern Ontario. Dickcissel is often very erratic in its breeding distribution--one year it might nest in large numbers in an area, while the next year, it might be totally absent from the same spot. These fluctuations are believed to be in response to rainfall and habitat conditions. The Bonny Lake State Park IBA in eastern Colorado is an Audubon IBA that regularly hosts breeding Dickcissel; in some years there are up to fifty breeding pairs at this IBA. The primary wintering grounds for Dickcissel are found in northern South America, although the species can also be found occasionally in Central America, and a few individuals overwinter in northeastern North America.

Since the 1920s, Dickcissel has begun to reoccupy, at least in small numbers, its former breeding range in the Atlantic Coast states. Overall, though, this species has recently exhibited population declines.

Ecology
Dickcissel nests in grasslands, meadows, savanna, and hay fields. Its nest is a bulky, loose cup of woven grass and leaves, usually placed in a grassy field. Males arrive at breeding territories about a week before females, and may have more than one mate. Females are responsible for nest building and incubation, usually of a clutch of four eggs. Young birds fledge a week to ten days after hatching, but are not capable of flight until a few days after leaving the nest. The diet of breeding adults is 70% insects and 30% seeds, while for young birds, it is the reverse: 70% seeds and 30% insects. Outside of the breeding season, Dickcissels feed mostly on seeds, including weed seeds and cultivated grains. Dickcissels migrate in flocks, sometimes gathering into groups of several hundred birds, and on their wintering grounds in the llanos of Venezuela, they are extremely gregarious, forming flocks that can number over one million birds.

Threats
The major threat to Dickcissel comes from its wintering grounds in Venezuela. Because of the species' propensity for gathering in enormous flocks and feeding on cultivated plants such as rice and sorghum, it can be a serious agricultural pest for Venezuelan farmers, who have sometimes taken to trying to poison flocks. Dickcissel flocks in Venezuela can number over a million birds, meaning that the wintering population can become highly concentrated at certain favored roosting sites. A single "successful" poisoning event of a large flock of roosting birds could significantly reduce the world population of Dickcissel.

On its North American breeding grounds, Dickcissel faces several additional threats: cowbird parasitism, the destruction of nests and nestlings by mowing machines, and loss of habitat due to changing agricultural practices and succession.

Conservation
In response to the threat to Dickcissel on its South American wintering grounds, a number of conservation groups, including Venezuela Audubon , have established an agreement with Venezuelan farmer's associations to develop a management plan for the species.

To monitor the passage of Dickcissels returning to the their breeding grounds in North America, the U.S. Fish and Wildlife Service has supported a pilot project by ornithologist William R. Evans to record the number of nocturnal flight notes given by Dickcissels as they pass over automated acoustic monitoring stations at high schools in the Rio Grande Valley of south Texas.

What Can You Do?
Audubon's Important Bird Area program is a vital tool for the conservation of Dickcissel as well as other species. To learn more about the Important Bird Areas program and how you can help, visit: http://www.audubon.org/bird/iba/.

To learn more about the Dickcissel Night Flight Call Monitoring project in south Texas, visit: http://www.oldbird.org/index.htm.

References
Ehrlich, P.R., D.S. Dobkin, and D. Wheye. The Birder's Handbook: a Field Guide to the Natural History of North American Birds. New York: Simon & Schuster, 1988.

Elphick, C., J.B. Dunning, Jr. and D.A. Sibley. The Sibley Guide to Bird Life and Behavior. New York: Knopf, 2001.

Farrand, John, Jr. The Audubon Society Master Guide to Birding. New York: Knopf, 1983.

Kaufman, Kenn. Lives of North American Birds. Boston: Houghton Mifflin, 1996.