Shrublands

Wildlife that rely on shrublands and grasslands are often considered “conservation reliant” species, meaning that without active habitat management they are likely to decline or even disappear from much of their ranges. Historically, many of these species were rare or absent in New Hampshire before European settlement. Grasslands were quite rare, and even those that resulted from beaver or Native American activity were too small to support grassland specialists. Most of the latter colonized the state during the peak land-clearing era in the 1800s, when vast swaths of forest were converted to farmland.

Shrubland birds have always been here, albeit in lower numbers. Many are adapted to small forest disturbances caused by fire, wind, or ice storms, and colonize such openings readily. They probably reached peak abundance in the mid-1900s as abandoned agricultural lands began to revert to forest. Thus the declines we see in towhees, thrashers, and similar species may predate the start of the Breeding Bird Survey in the 1960s, and losses of shrubland habitats have continued unabated.

The question often facing conservation biologists is some variant of “how many early successional species are needed” in a particular landscape. To restore towhee or Bobolink populations to 1970 levels might require extensive clearing of now-forested land, which could be harmful to forest birds. Some shrubland and forest birds can coexist, but usually in more complex habitats like pine barrens. Although declining, most shrubland species remain common, and a more feasible strategy may be to stabilize populations rather than trying to restore them to a larger portion of the landscape. For grassland birds, where habitat creation is unlikely, the best we can do is work towards maintaining existing habitats where we can, and be prepared for further declines. From a species perspective, it is more cost effective to conserve these declining species in the Midwest and Great Plains where they remain relatively common.