Dickinson Ch11: Ruffed Grouse

I. General Characteristics and Biology

The ruffed grouse is a dedicated quarry for upland bird hunters in the Southern United States.
Males advertise presence by "drumming" in spring, which is an indicator of young forest stands and early-successional communities.
Clinal Variation (Body Weight and Coloration):
- Grouse generally follow Bergmann's rule (northern birds are larger).
- Contradiction: Southern adult males in the Appalachian forests (e.g., North Carolina and Georgia) are often larger (24.1 oz.) than northern counterparts (22.6 oz.).
- Color variations range from light silver-gray to deep red-brown. Red-phase birds dominate the southern edge of the range.

II. Distribution and Population Status

The ruffed grouse is North America's most widely distributed Tetraonid.
The southern boundary of the range extends to northern Georgia and the extreme northern edge of Alabama.
Grouse are generally more common above 1,500 feet elevation in the Southeast.
Southern populations have declined in recent years, particularly in the Southern Appalachian Mountain region.
Warm southern climates are potentially detrimental to grouse distribution.
Historically, widespread logging (19th and 20th centuries) and the abandonment of family farms created dense, young forest habitat, supporting grouse populations.
Today, isolated populations are primarily supported by highly fragmented landscapes.
Unlike northern populations, southern populations do not exhibit the pronounced 10-year periodic population cycles.

III. Food Habits

Southern grouse feed primarily on herbaceous vegetation year-round, with succulent broad-leaf herbs available mid-spring through late fall.
Winter diet relies heavily on succulent herbaceous vegetation, supplemented with fruits (grape, greenbrier, hawthorn) and evergreen broad-leaf plants.
Low quality of winter foods may contribute to lower grouse recruitment and populations in the South.
Chicks feed primarily on insects during their first few weeks of life.

IV. Habitat Requirements

Habitat quality is strongly correlated with stem density and shrub regeneration.
Young forest stands (5–15 years old) are optimal, requiring high densities of woody stems (8,000–10,000 stems/acre) for cover against predators.
Grouse thrive in early successional forest stands often created by tree harvest.
Thermal Protection: Conifers (spruce, fir, red cedar) provide essential thermal protection during prolonged, severe winter weather in the South.
Drumming Sites: Preferred sites are typically large diameter, partially decayed fallen logs, rocks, or elevated perches.
Nesting: Hens require dense, highly structured habitat (shrubs or overgrown agricultural fields).

V. Habitat Management and Silvicultural Options

Ruffed grouse are habitat specialists.
Silvicultural treatments (man-made disturbances) are necessary today, replacing historical disturbances like fire and ice damage.
Required Treatments: Clearcut, seed-tree, and shelterwood regeneration treatments are used to produce the dense stem requirements.
Overstory Removal (Basal Area Reduction): To produce quality regeneration, residual basal areas generally need to be less than 20 sq. ft./acre.
Size of Harvest Unit: Optimal harvest unit size is small and scattered, ranging from 0.25 to 10 acres.
Herbaceous Openings: Maintaining these openings provides forage quality and increases arthropod (protein) sources for chicks.
Conifers: Small planted patches (0.5 acres or less) of Norway spruce or white pine provide critical winter refuge.

VI. Future Trends

Ruffed grouse populations are declining throughout much of their range in the Southern U.S..
Commercial timber harvest has largely replaced fire as the primary agent of forest disturbance.
A significant portion of timberland (70%) in the Southern U.S. is owned by non-industrial private forest (NIPF) owners.
Public land agencies often face public concerns regarding aggressive habitat practices like clearcut regeneration.