BIOLOGICAL DATA AND HABITAT REQUIREMENTS
WILDLIFE SPECIES: Bonasa umbellus | Ruffed Grouse 



TIMING OF MAJOR LIFE HISTORY EVENTS : 
Mating and Courtship - begins in April with males "drumming" to attract
                       a mate
Nesting - clutch laid about 3 weeks after mating; usually
          8 to 14 eggs over a 15 day period; nests on ground
          near base of tree or stump
Incubation - 23 to 26 days; hatch from late May to early July
Fledgling Age - 8 to 10 weeks; usually only three to four chicks survive
                their first summer
Lifespan - 7 years; 55 percent mortality rate of fall population
           during the winter
Migration - none
[16,17,20]


PREFERRED HABITAT : 
Throughout most of their their range, ruffed grouse prefer pure stands
of quaking aspen or quaking aspen mixed with other hardwoods or
conifers.  Ruffed grouse chicks find protection in dense, young quaking
aspen suckers as early as 1 year after fire or other disturbance [23].
Pole-size quaking aspen stands appear to offer the best breeding habitat
and may support one breeding bird per 3 to 4 acres (1.2-1.6 ha).
Breeding generally does not occur in quaking aspen stands exceeding 25
years of age or with a density less than approximately 2,000 stems per
acre [6].

A study in northern Idaho showed that ruffed grouse chose hardwood areas
more often than coniferous forests during winter and that quaking aspen
was preferred during all seasons [31,34].  Another northern Idaho study
showed that ruffed grouse spent winters on ridges above ravines at an
elevation of 3,500 feet (1,067 m).  Air temperature on these ridges was
warmer than below due to warm air inversion.  Ruffed grouse then moved
into ravines during summer, where temperatures remained cool [24].

In some parts of their range, ruffed grouse use conifer-dominated stands
during winter [17,24,31,34].  Ruffed grouse also use woodland areas in
early seral stages with a high shrub density [27].

Gullion [16] stated that ruffed grouse rarely die more than 5 miles (8.3
km) from where they hatched.  Males usually choose drumming logs within
2,000 feet (610 m) of their brooding range [20].  Females have a home
range of about 100 acres (40.5 ha), while males occupy closer to 10
acres (4 ha) [16,20].



COVER REQUIREMENTS : 
Gullion [20] reported that cover requirements for ruffed grouse can be
met in pure aspen stands if those stands have a mix of age classes and
enough good quality male clones to meet the energy requirements of
ruffed grouse.  Newly regenerated aspen stands provide nesting cover for
up to 10 years, while 10- to 25-year-old aspen are good for
overwintering and breeding.  Stands older than 25 years provide nesting
cover and food [6,30].  Deep snow accumulation, essential for wintering
ruffed grouse, which need to burrough in the snow for protection against
cold and predators, occurs earlier under hardwood than under coniferous
cover [20].

Much of the ruffed grouse habitat requirement studies have been
conducted in Minnesota by Gullion, who reported that the growth form and
tree characteristics are more important to ruffed grouse survival than
tree species [22].  Gullion and Marshall [22] concluded that as the
density of mature pines increases, survival of ruffed grouse decreases.
They also stated that ruffed grouse inhabiting edge communities do not
live as long as those inhabiting uniform habitats.  Ruffed grouse use
hardwoods more heavily in the East, while ruffed grouse in the West will
use coniferous cover [24].  Ruffed grouse in Wisconsin use hardwood
cover between 4 and 7 inches (9.8-17.2 cm) d.b.h.  [10].  Ruffed grouse
here distribute themselves throughout all cover types, except open
habitats.  Pure conifer types are not very important as cover.

Thick ground vegetation is more beneficial to ruffed grouse predators
than to ruffed grouse [18].  For this reason ruffed grouse need a
viewing radius of 50 to 60 feet (15-20 m) at all times.  Drumming logs
need to be 12 to 14 inches (29.5-34.4 cm) above the ground with the same
viewing radius; however, low, dense shrubs and brush need to be within
10 to 12 feet (3.3-4 m) on all sides [20].


FOOD HABITS : 
Quaking aspen is the primary food of ruffed grouse throughout most of
their range.  Quaking aspen buds, catkins, and leaves provide an
abundant and nutritious, year-long food source for ruffed grouse
[6,23].  Vegetative and flower buds are the primary winter and spring
foods of the ruffed grouse.  Ruffed grouse eat 6 times more quaking
aspen buds than buds from all other species combined [23].  It is
estimated that ruffed grouse can consume more than 45 quaking aspen buds
per minute and can satisfy their daily winter food needs in as little as
15 to 20 minutes [6].  

Ruffed grouse also eat the fruits, nuts, twigs, leaves, and flowers of a
variety of shrub, forb, grass, and tree species.  These food species
include willow, elm (Ulmus spp.), hazel, birch (Betula spp.), oak mast,
dogwood (Cornus spp.), huckleberry and blueberry (Vaccinium spp.),
current (Ribes spp.), viburnum (Viburnum spp.), sumac (Ghus spp.),
cherry (Prunus spp.), rose (Rosa spp.), serviceberry (Amelanchier spp.),
greenbriar (Smilax spp.), mountain-laurel (Kalmia latifolia),
wintergreen (Gaultheria procumbens), strawberry (Frageria spp.),
dandelion (Taraxacum spp.), and wild lily-of-the-valley (Maranthemum
canadense) [2,6,7,8,15,21,30,36,37,39,40].  Chicks feed heavily on
insects and other small invertebrates [2,11,40].


PREDATORS : 
Ruffed grouse predators include humans, wolves (Canis lupus), coyotes
(C.  latrans), foxes (Vulpes spp.), cougars (Felis concolor), lynx (F.
lynx), bobcat (Lynx rufus), hawks (Buteoninae), falcons (Falconidae),
owls (Tytonidae), eagles (Strigidae), snakes, skunks and weasels
(Mustelidea), and other small carnivorous mammals [18,20,38].


MANAGEMENT CONSIDERATIONS : 
Gullion has detailed the management of aspen stands to create ruffed
grouse habitat [19,20,21].  He stressed the importance of maintaining
male aspen clones and recommended cutting aspen at 40 to 60 years of
age.  Gullion also recommended slash removal to reduce predator hiding
cover, and provision of four age classes of aspen for nesting, brooding,
and adult overwintering [19].  Perala [30] and Brinkman and Roe [6] have
also listed management strategies for aspen stands.


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Bonasa umbellus | Ruffed Grouse