The dickcissel is omnivorous and, during the summer breeding months, feeds on a range of seeds and invertebrates (2) (3). Seeds are either foraged for on the ground or plucked directly from the plant whilst perched on a plant stem. The outer covering of the seed is then removed before being eaten (2). On migration and during the winter, the dickcissel is highly gregarious and forms flocks, some of which are so large they may contain between 10 and 30 percent of the global population. During this time the dickcissel is described as being ‘granivorous’ as its diet consists mainly of seeds, often from food crops (2).
The breeding season for the dickcissel varies depending on location, but usually begins in May or June. The male dickcissel will defend a territory that contains both suitable nesting and foraging areas, and will vigorously chase away any intruding males (2). Males with territories containing the best nest sites will attract more females (2).
The female alone is responsible for selecting the nest site, building the nest and then brooding and raising the young. The dickcissel’s nest is usually placed slightly above the ground, in dense vegetation, and consists of a bulky cup woven out of weed and grass stems (2) (3). A clutch of 3 to 6 pale blue eggs is laid and is incubated for around 12 to 13 days. The young dickcissels are fed on a variety of invertebrates and leave the nest at around eight to ten days old (2).