Ruffed grouse

The weight of a grouse is about 1½ pounds, their body length is 15½ to 19 inches, and their wingspread is 22 to 25 inches. The bird’s plumage is rich brown sprinkled with white and black above, and white with horizontal dark brown bars on the breast and undersides. The tail is brown and has a wide, black band between two narrower grayish bands. The name “ruffed” comes from a ruff of iridescent black feathers that almost completely encircles the neck

Two interesting color phases occur. Gray phase or ”silver” birds have gray in place of brown in the tail; “cinnamon” grouse have rust-colored feathers with a chestnut—rather than black—ruff and tail band.

Males (drummers) differ from females (hens) in several ways. Males weigh a little more than females, and they have more prominent ruffs, which are erected during courtship display. The hen has a shorter tail, and the solid black tail band is generally grainy, fuzzy or broken on the center two feathers. This is often the case with first-year males as well. An adult drummer’s band is uniform and continuous across all tail feathers. Adult grouse molt once each year from July into September. During this time, grouse may be hard to find as they seek thick protective cover. Flight feathers are replaced gradually in order to maintain flight, though many or all of the long tail feathers may be dropped at once.

Grouse are found throughout Pennsylvania in suitable habitat and are year-round residents. Adults in good habitat rarely range more than a few hundred yards a day unless pressed by predators or hunters; in fact, the same bird may be flushed from the same area in the woods several days in a row. Poor habitats, like mature forests, force grouse to range further afield in search of food, which increases their predation risk in the open understory of a mature forest.

Grouse eat many types of food. In the summer, they consume insects (which are rich in protein), blackberries, blueberries and other wild fruits. In fall, when insects are scarce, they feed almost exclusively on acorns, beechnuts, cherries, wild grapes, crabapples, hawthorn and dogwood fruits, and various buds and leaves. Buds form the basis of the grouse’s winter diet: aspen, birch, beech, maple, cherry and apple buds are favored. Throughout winter and early spring, ferns, green leaves and other evergreen food are eaten until other foods become plentiful. Grouse do well in areas without visible water sources, obtaining moisture from their diet.

Like most birds, grouse have keen eyesight and hearing. At one time, they were not nearly as wary as they are today; early settlers killed them with sticks and stones. Today you may surprise a grouse bathing in the dust on a back road, in a sandy spot of earth, or in the debris around a rotting stump. Dust bathing may stimulate feather growth in young grouse, maintain adult plumage or rid birds of external parasites.

Grouse shelter beneath conifers during stormy weather and roost in conifers and hardwoods. They may spend winter nights in a ‘snow roost’ hidden beneath the surface, sometimes flying directly into a soft snowbank at dusk. Grouse are usually loners, although groups of birds are sometimes found together in the fall and winter. In winter, grouse feet develop a comb-like fringe along the edge of each toe that helps them cling to icy branches provides extra gripping power when walking on crusted snow.

Grouse walk more than they fly. Although a grouse flush is thunderous and powerful, they cannot fly long distances. Top flight speed is 20 to 35 mph. After this rapid take-off, it then locks its wings and glides to safer territory, usually traveling less than 100 yards. During mating season—March and April— male grouse attract females by drumming. With tail fanned, the male stands on a large, prominent log or rock and beats the air sharply with his wings. The rush of air created by his wingbeats sounds much like drumming. The drumming starts slowly and increases in speed, until the individual thudding beats merge into a fast, steady whir. Males also fight and display for females; displaying males fan their tails, erect their ruffs to encircle their heads, then hiss and drag their wingtips along the ground

A mated hen picks a secluded nesting site, usually at the base of a tree or under a fallen log, and lays 6 to 16 white or buff eggs in a leaf-lined depression in the ground. The hen may re-nest if nest destruction occurs. The incubation period is approximately 24 days. The male does not help the female incubate eggs or brood young.

Chicks are precocial and the hen will usually lead them away from the nest within 24 hours of hatching. Chicks develop rapidly. Within their first week, chicks are capable of low buzzy flight. At three weeks, they can fly well. By autumn they look and act like adults. In early fall, birds of the year may exhibit a strange period of restlessness known as the “fall shuffle” or “crazy flight.” During this time, young grouse take off in undirected flight and may be killed when they crash into trees, fences, windows and walls. The fall shuffle may serve to scatter broods, and mix the genetics in a population. Juvenile mortality is high. Studies indicate more than three quarters of all chicks die within 35 days of hatching – the majority die from predation or exposure within the first week. Among adults, annual survival is roughly 50 percent, and relatively few live to be two years of age.

Habitat is the most important factor affecting the size of Pennsylvania’s grouse population. Healthy young forests provide multiple benefits to ruffed grouse. Forests less than 20 years old offer abundant food in all seasons, protection from predators, and safe spaces during severe weather. Recent data indicates that grouse populations recover more quickly from West Nile virus losses in areas of high-quality and highly-abundant habitat. These healthy young forests support many other declining game and non-game species and managing young forests furthers the Game Commission’s goal of managing healthy and resilient forests for future Pennsylvanians.