Updated: Mar 22
The Logo for the Pennsylvania Breeding Bird Blitz for Conservation includes a Ruffed Grouse which is of course the Pennsylvania State Bird. It is also contains the letter B which does triple duty in representing the words "Breeding Bird Blitz," the number 4 which represnts the word "for," and the letter C which represents the word "Conservation." More information on the Ruffed Grouse which is a bird of conservation concern in PA follows below. Sources for the following include the PA Game Commission, Eastern Grouse Working Group, and Ruffed Grouse Society.
Ruffed grouse populations have declined by at least 50% throughout the Eastern U.S. since the turn of the century. Loss of young forests across the landscape is the primary driver of this decline. Climate change, increasing predation, changing land use that fragments habitat, and mortality from West Nile Virus are also contributing factors.
Grouse use different-aged stands for different reasons in different seasons. Forest openings with downed logs and scattered saplings make excellent brood habitat. Dense sapling thickets are used for drumming and courting. Mature forest often is used for winter cover, nesting, and feeding on nuts, twigs, buds, and fruit.
For nearly a century, Pennsylvania has been losing young forests resulting in the steep decline of habitat needed for two of the three critical life requirements for grouse: brood rearing and courting. In response, grouse populations have steadily declined, shifted northward, and become ever-more restricted to localized areas of suitable habitat.
The most recent Partners in Flight Conservation Assessment identifies Bird Conservation Region 28 (which includes most of Pennsylvania), as having a threat level score of 4, indicating a severe deterioration in the future suitability of conditions which is expected to significantly affect a majority of the population. Additionally, the Ruffed Grouse is listed on the Pennsylvania Species of Greatest Conservation Need, which estimates that the young forest acreage that supports the grouse population is 12 to 14 percent below what is needed.
Loss of young forests impact not only grouse but also forest health, forest resilience, and the entire suite of Species of Greatest Conservation Need that rely upon young forests. Declining grouse populations are an urgent indicator of the plight of other species which use young forests during critical life stages, including many we class as "mature forest" species.
In some areas, suitable habitat remains unoccupied because it is too isolated to be re-colonized. In many areas that continue to hold grouse, population persistence is severely compromised because reproduction and immigration do not outpace mortality. In areas of high-quality habitat, grouse may still occur at high densities, and habitat remains key to population recovery. Monitoring by the Pennsylvania Game Commission suggests that populations in regions of high-quality habitat experience West Nile Virus related declines but recover more quickly than those in regions of marginal and fragmented habitat.