Rusty Blackbird

During the breeding season the Rusty Blackbird is a secretive denizen of shrubby wetlands in northern New Hampshire and generally requires a little effort to find. They are much easier to see in migration, when they sometimes join flocks of other blackbirds to forage in agricultural fields and wetland edges. In the fall they have molted into the brownish plumage from whence they get their name. Over the winter the brown edges wear off to reveal the black (male) or gray (female) base colors the birds wear through the breeding season. At all times of year they sport piercing yellow eyes, a feature shared with the far more common – and significantly larger – Common Grackle.

The Rusty Blackbird is one of the most rapidly declining songbirds in North America, with some estimates placing current numbers at less than 10% of those in the 1970s. Reasons for this decline are still poorly understood, but one leading culprit is habitat loss during the non-breeding season. In winter and migration Rusties prefer wooded swamps and wet thickets, and much of this habitat in the southeastern United States has been converted to agriculture. There is also speculation that this species has been an inadvertent victim of programs to control blackbirds (usually by poisoning) during the winter.

There are threats on the northern breeding grounds as well. Some research suggests that birds are more productive in wetlands not adjacent to timber harvests, possibly because of increased predation pressure. These same habitat changes may also result in increased populations of competitors such as Red-winged Blackbirds and grackles in Rusty Blackbird habitat. Climate change has the potential to alter wetlands through both drying and flooding, making it harder for Rusty Blackbirds to forage. Many of these threats are the subject of ongoing research efforts, including some in New Hampshire, that hope to identify future actions that can reverse or stabilize declines.