The Brown Thrasher is one of three birds that are common throughout much of the US belonging to the Mimidae family of birds. As you will note they are all good at mimicry. The Mockingbird is more common in the mid-south and on down to the gulf and Mexican border. The Catbird gives out single notes in it’s songs. And while the Brown Thrasher uses doublets, the Mockingbird will repeat phrases three or more times. They are all good singers, but the Mockingbird is the undisputed champ.
The Brown Thrasher normally reaches the Midwest in April and the male will sing loudly from high perches announcing his territorial claims and trying to attract a mate. When nesting ensues, they become much more secretive. He will still sing, but much softer and from sheltered areas, and is harder to observe. Their nest looks similar to their close cousins and is well hidden in dense cover. They use fine twigs lining the nest with rootlets. Thrashers defend a territory of two to ten acres, remaining close together for several weeks, before nest building begins.
The nest may be built on the ground or up to fifteen feet above the ground in a dense area. Both parents build the nest, but the female seems to do most of the shaping. She will lay from three to six eggs, while the average seems to be four or five. Both parents incubate, but the male is more nervous on the nest. He will spook quickly, while the female sits tight until the last minute flushing. In twelve to fourteen days the young will hatch and will remain in the nest from nine to twelve days. They are fed by both parents and this continues into the fledgling phase. If there is time for a second brood, the male assumes all feeding duties and she will proceed to attend to the second nest. If not, each parent takes it’s share of the young and may even move from the original territory. They are very defensive of the young and will even attack humans if they deem it necessary. The young will have a gray iris in their eyes, while the adults are a bright yellow. Their migration from our area is normally September or October.
Contributed by Mr. Weir Nelson of Wildlife Habitat, Cedar Rapids, Iowa