Several years ago, I was invited to attend a bioblitz in southern Missouri on one of the few prairies remaining in our state. For those that do not know what a bio blitz is; it is an annual event usually hosted by environmental-minded groups to inventory the plant and animal life found on a prairie or other natural area. For this particular blitz I was there as the “expert” entomologist. I am far from an expert, but I am not one to turn down an opportunity to hang out with a group of like-minded people with something to teach me. The prairie is a wonderous place with so much diversity in plant, bird, and insect life. One of first things I began to notice were these beautiful birds perched on fence posts in various spots around the prairie. They resembled meadowlarks but were much smaller. They were too colorful and big to be sparrows and since I had never seen one before I wasn’t sure what they were. Soon I had an ID from one of the bird experts in attendance.
This beautiful little bird was a Dickcissel, originally, they were referred to as black throated buntings. Scientists have had an exceedingly difficult time classifying these birds and they have undergone several classifications over the years before finally landing in their current group classification of Cardenolide. Males are very colorful and somewhat resemble meadowlarks with their black collar and yellow breast. Females on the other hand are muted in coloration by comparison and look more like sparrows. Both sexes have a yellow line above their eye, a rusty patch on their wings and a light-colored conical bill that very much resembles the bill on a cardinal. Which is one of the reasons they are currently classified in the same family group as cardinals. Although as more information is learned about them, this could likely change. The dickcissel gets its name from the call they make while in flight. It can vary some in the syllables as well as the intensity, but it usually goes something like this “dick-dick-dickcissel-cissel.” This unmistakable call helps ornithologist identify them during nighttime migration events and allows for monitoring of population densities.
They are a common sight throughout the Midwest during the late spring and summer months. These birds migrate back into the United States late in May or early June, which is much later than most birds returning to their breeding grounds. Dickcissels nest near the ground and typically build their nests in grassy meadows, prairies, or other tall grass areas. Males may have as many as six mates, although two or three is typical. Males will vigorously guard their territory from rival males. While the males are busy puffing out their chest and chasing off the competition, the females are looking for suitable sites to build their nest and lay their eggs. Once the eggs hatch the female will rear them to full fledglings on her own. After the young leave the nest, they go their separate ways. Unlike many bird species that mate for life, the dickcissel is a polygamist and will have multiple mates and a whole new set of mates the following year. Young bachelor males often do not get the chance to mate, but they will have the opportunity next season.
In their winter range they may be a pest to grain farmers because of their habit of forming large flocks and feeding on the grain seeds. Early in fall these birds begin forming loose flocks that gradually grow in number by mid to late fall. It is common for a flock heading south to contain millions of birds. It is this tendency to congregate in such large flocks that causes so much trouble for grain farmers in their overwintering sites. They head south to Southern Mexico, Central America and Northern South America where Venezuela is especially plagued with these birds and have traditionally used poisons and other methods of ridding themselves of these birds. Fortunately, various bird groups and other environmental groups have done an excellent job of educating farmers in these areas on other methods to scare of a hungry flock of these birds. In the Midwest breeding grounds, dickcissels face 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. Additionally, the use of pesticides kills off the insect population they depend on while rearing young. With the increase in wind turbines, we are also seeing an increase in deaths during migration events when birds fly too close to the spinning blades. The wintering population of these birds 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. Currently the estimated population is at twenty-seven million, which sounds like a lot of dickcissels, but we all known how quickly that can change…. just think about the Carolina parakeet or the passenger pigeon that historically numbered in the millions and are now extinct.
Formerly common in farming regions of the eastern states, especially on the Atlantic coastal plain, the dickcissel disappeared from that region by the middle of the last century and is now most numerous in the Midwest. It appears in small numbers on the East Coast during the fall migration and on occasion will visit winter feeding stations, often with house sparrows.
Since my initial introduction to the dickcissel on the prairie that weekend in southern Missouri, I have become more cognizant of the species around me and frequently notice the dickcissel on our farm. They are always a welcome sight in the summer as they sit on the fence posts singing “dick-dick-dickcissel-cissel.”
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