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| EASTERN COTTONTAIL | APPALACHIAN | SNOWSHOE HARE |
Lagomorphs
are primitive placental mammals dating to the Paleocene times, about 62
million years ago in Asia. This order includes two families in the world.
The Ochotonidae family includes the pikas in the western US.
Hares and rabbits are in the Leporidae family.
The greatest radiation of species has occurred in North America. Ears, used for defensive purposes, are largest in hares, who
live in open habitats, and smallest in pikas, living in the protected
environment of talus slopes.
Although similar in resemblance to rodents (with substantial evidence indicating they should both be put together in a superordinal group known as Glires), this is more a function of their similar herbaceous life style (convergent evolution) than direct evolutionary relations. In fact, some studies now suggest that lagomorphs are more closely related to artiodactyls (even-toed hoofed mammals) than rodents.
Both rodents and lagomorphs have a pair of large
upper incisors that grow throughout their life, but the lagomorphs have a
smaller pair right behind the first. (In fact, even a third set of
incisors is present in the lagomorphs at birth, but is soon lost.)
One
slight difference exists in that the large incisors in lagomorphs are covered
both front and back by enamel, while only the front of the incisors is covered
by enamel in rodents. A space
exists between the incisors and the remaining cheek teeth. This space (diastema)
is the space occupied by the canine tooth in many mammals. Canine teeth are
absent in rabbits, hares, and all rodents. More significantly (at least to the
rodents), rabbits and hares lack a penis bone (baculum), that is found in
rodents.
Lagomorphs
are herbivores that practice coprophagy, the re-ingestion of fecal droppings.
On first "pass", these soft, green pellets pass through the
digestive system only partially digested. These pellets, rich in protein and B
vitamins, are re-ingested directly from the anus.
After reingestion, the pellets are a drier brownish in nature.
This practice allows the animals to spend relatively little time
exposed to predators while in the field actually feeding.
They consume green vegetation rapidly and then make optimum use of it
in the safety of their cover. This
process is also called "pseudo-rumination", since it is functionally
the same as cows chewing their cud. Coprophagy is also practiced by beaver and
voles and, apparently, by some shrews.
Worldwide, there are only two families, with 13 genera and 81 species in the rather small lagomorph order (Nowak's Walker's Mammals of the World). None were native to Australia.
Five
genera and 20 species are found in North America (including the introduced
European rabbit and European hare), with three species in the
Appalachian region; all in the Leporidae family (Jones).
Rabbits
and hares (leporids) differ in that rabbits give birth to altricial young (naked, closed
eyes, requiring some time in the nest before ready to roam), while hares give
birth to precocial young (born with hair, open eyes and ready to run) and
don't 'make nests.
Correspondingly, less postnatal care is necessary for hares than rabbits
(however, hares have longer gestation periods). Hares are creatures of open habitats and are
specialized for running (up to 40 mph). Rabbits
inhabit more brushy habitats, have shorter legs, and thus, do not run as well.
Rabbits make their fur-lined nests in dense vegetation with smaller
home ranges while hares live in simple depressions in open habitat and
have large home ranges (Wilson says hares prefer rock crevices and caves).
While European rabbits make permanent extensive burrows, our North American rabbits and hares
do not dig burrows (nor do they dig up carrots).
Instead, they make well-concealed shallow "forms" on the
surface. Rabbits and hares will
use burrows of woodchucks and skunks during periods of bad weather, never
venturing far inside. Rabbits
tend to run for cover when threatened, while hares, adapted to a more open
habitat, will opt to out leap and outrun predators.
Rabbits
can be gregarious, while hares are often solitary. In areas with high densities of rabbits, females form
dominance hierarchies, with the dominant females suppressing the reproduction
of subdominants by denying them access to nest sites and by physical
intimidation.
Both
rabbits and hares produce relatively large litters and are prodigious
reproducers, with large populations maintained; supplying a significant food
source for many predators (high fecundity is balanced by high mortality).
This is known as an r-selected strategy. (The
other primary reproductive strategy is k-selected
species which produce low numbers of young but a much greater proportion
of the young enters the breeding populations.) Reproduction is increased by a
phenomenon known as induced ovulation. Basically,
ovulation is induced by copulation (like cats).
In both cases, the scentless young are left alone in the nest for the
first few weeks, with the mother nearby feeding, in order to protect them from
predators. The mother only approaches for a short period, often at night, for
nursing and then leaves the young again.
The females (does) are known to grunt or purr while nursing. The males
(bucks) offer no parental care.
Northern
forms frequently have larger litter sizes and shorter gestation length than do
southern ones. This adaptation
takes advantage of the shorter growing season while maximizing the food
resources.
The
phrase, “Mad as a March hare” comes from the springtime mating antics of
female hares, sizing up the courting males.
Females stand up on their hind legs and cuff males in the face and
ears. Female hares and
rabbits are normally larger than males, indicative of the evolution of
selection for combative females.
Regarding
the courtship behavior of lagomorphs, the following describes the snowshoe
hare, “The male snowshoe approached
the female, sniffed her and jumped into the air.
After landing, the male urinated on the female and left.
The male re-approached
the female, and the female jumped into the air twice, after which the male
left. The male returned, jumped
into the air and urinated on the female.
Both snowshoes then went into the bushes, where more jumping occurred.”
Similar courtship behavior is practiced by other hares and rabbits.
In contrast to the case in most mammalian families, female leporids are usually larger than males.
Scat
resembles chocolate M& M’s; dark brown, round and slightly flattened. In
addition to these fecal pellets, soft, greenish pellets are formed that are
only partially digested and will be re-ingested directly from the anus through
the process known as coprophagy, as noted above. Found in groups of 5 to 10.
Rabbit
tracks have four front and rear toes, often with claws showing.
There are 11 genera and 54 species of rabbits and hares in the world (Nowak), with 5 genera and 18 species in North America (Checklist of North American Mammals), of which two species are introduced.
Two
species of rabbits (Sylvilagus) and
one hare (Lepus) exists in the
Appalachian region. These are the eastern and Appalachian cottontails and the
snowshoe hare.
EASTERN
COTTONTAIL (Sylvilagus
floridanus) (forest, hare; from Florida)
Appalachian
Region Distribution:
Throughout.
Continental Range: East of the Rockies and south of Canada
throughout Mexico and Central America. Seven
subspecies have been recognized by W/H, however, Chapman and Feldhamer note
that subspecies are somewhat meaningless, due to the wide transplanting of
this species that has occurred with time.
Abundance: Common.
The widest distribution of all of the cottontails.
The range of this species overlaps that of seven other cottontails and
six species of hares.
Population Density: 2-5 /acre.
Novak reports 4/acre in Maryland. W/H reports up to 9/acre, but normally
much lower. Periodic cycles may have occurred in
historic populations, but recent land use changes has more profound impact on
population densities than any natural functions. Nesting density is habitat-specific. A PA study found nests every 1.5 acres in unkempt orchards, 7
acres apart in hayfields, 13.5 acres in woodlands, and 14 acres required for
nests in pasture lands.
Size and Molt: Head and body 14 -
19 inches; 2 - 3 pounds. Females
slightly larger than males. Two molts.
Mammae: Four pair.
Habitat: Everywhere but wet areas.
Prefers heavy brush. (On the southern and southeastern peripheries of the
region (lower elevations), the swamp and marsh rabbit will inhabit these
areas.)
Active Period: Chiefly crepuscular
to nocturnal, active from early evening to late morning. Spends days resting
in a "form"; a small, scratched-out depression in a clump of grass.
Can be observed "sunbathing" on warm days. Active year-round.
Diet: Herbivorous, green vegetation
in summer, twigs in winter (especially dewberries and blackberries). Easier to
identify what is not eaten by rabbits. Practices coprophagy (see Order
Lagomorpha above).
Home Range: 2 ½ to 5 acres is
normal, with a range from 1 to10 acres (depending on populations, habitat
quality, season and sex, with the male having a slightly larger range).
Ranges for males are the largest in the main breeding period of late
spring-early summer, while females have the smallest range at this same
time. Dominant males have the largest ranges. Ranges are generally smaller in spring
(before breeding) and
winter reflecting lush vegetation and severe limiting weather. Not being territorial, ranges
of individuals often overlap (up to 50% for males and 25% for females in
spring), especially in winter, when they tend to concentrate in areas offering
the best combination of food and cover. Chapman and Feldhamer report
females have little or no overlap of home ranges during breeding season.
Social Structure: Solitary, generally
not territorial, except for females in the immediate vicinity of a nest.
Males
have a dominance hierarchy in which the most dominant have more aggressive
encounters with other males and do most of the mating. Dominance hierarchy of
males allows the strongest males to fertilize more females than subordinates
and also minimizes fighting. Most aggressive behavior is exhibited between the
dominant male and the individual immediately below it in social status.
Females have a less rigid hierarchy. Females exhibit dominance over males except during estrus.
Life Cycle: Breeds throughout the
growing season (from February through September) with three to five litters per
year (can be up to 7 litters in warmer seasons) with an average of 5 per litter (can be as
many as 12). Throughout its North American range, litter size increases with
latitude (from 3 to 5) and gestation period of about 28 days. The female comes into estrus
immediately after giving birth (post-partum estrus and pregnancy).
Like all cottontails, they are synchronous breeders (all members of a
population tend to breed at the same time).
After four to five weeks, the altricial young are weaned and leave the nest and the
mother gives birth again. Thus, the mother is pregnant most of the season.
45%
mortality of newborns within the first month, with 80% mortality by the end of
the first year. In our Appalachian
region, most females and virtually all males will not breed until the
following spring. Up to half of the
newborn female young will breed their first season in the southern states.
Usually, about 80 - 85% of the cottontail population are juveniles. Life span of two years is reached by only 25 % of adults.
Nest: North American rabbits don't
dig or live in
"rabbit holes", as some slower European species do, although they will
occasionally utilize groundhog holes.
Other places of shelter include brush piles. Nesting
is done in well-hid surface depressions, or “forms”.
This elaborate nest is more of a slanting hole; six to seven inches
long, five inches wide, four to five inches deep, lined with grass and then
covered with the mother’s hair. Newborn
are covered with nest material during the day while the mother feeds nearby.
The mother returns to the nest at night to feed the young.
She does not actually reside in the nest; she merely crouches above it, and
the babies climb to the top of the nest to nurse. They will use underground dens of woodchucks as a temporary home, especially
during winter storms.
Tracks: The normal hopping pace
produces the well-known "Y" form, with the front two feet forming
the stem of the "Y" and the larger rear feet landing in front
forming the two top sides. Usually, the snowshoe hare does not overlap the
range of the eastern Cottontail. Normally will make straddle trails 4-5
inches wide.
Scat: Similar in shape to "M
& M’s"; about 3/8" in diameter.
One rabbit may void 250 to 500 pellets in a day.
Remarks:
The eastern cottontail can jump 10 to 15 feet. They can often be differentiated from the Appalachian
cottontail (next listing) by a white spot on its forehead, whereas, the
Appalachian cottontail often has a black spot between the ears.
Urinating on the partner is a part of the mating ritual. Rabbits
are r-selected, exhibiting massive births with few surviving to
adulthood versus k-selected, which
emphasizes few young with high percentage making adulthood.
Valued as the most important game species in many parts of the eastern US, the eastern cottontail can be infected with the disease
tularemia, a bacterial disease that can be transmitted to man handling the
rabbit with open cuts.
In flight, will stay in its known range, often circling in a large loop back to its original site and often jump sideways to break their scent trail.
Many millions of rabbits are killed each year.
APPALACHIAN
COTTONTAIL (Sylvilagus
obscurus) (forest, hare; obscure)
Appalachian
Region Distribution:
Throughout higher elevations from PA to GA.
Continental
Range: Same. The type locality is
Dolly Sods, WV. No subspecies
are described. It is postulated that unbroken woods, rather than high
elevation, delineates the distribution of the Appalachian cottontail.
See remarks for a detailed WVA range.
Abundance: Uncertain, never
abundant, but declining due to deforestation.
A candidate for designation as
federal endangered species.
Population Density: Unknown
Size and Molt: Head and body 14 - 16"; 1 ½ - 2 ½ pounds. Females are slightly larger than males. One
molt, unlike the Eastern Cottontail.
Mammae: Four pair.
Habitat: Dense forests and thickets
at high elevations, especially birch/red maple forests, hemlock and
rhododendron areas within oak-hickory forests, blueberries, mountain laurel
and coniferous forests. Has a noted preference for six to seven year old clear
cuts and old overgrown farmsteads and pockets of heath-conifer habitat.
More specialized than eastern cottontail.
Active Period: Active from
early evening to late morning (nocturnal).
Diet: Less varied than eastern
cottontail, although some studies conclude that dietary preferences are nearly
identical. The only cottontail
that feeds extensively on conifer needles.
Home Range: ½ to 1 ½ acre.
Social Structure: Exhibits both
solitary and social behaviors. They
groom and dust alone, but vocalize amongst themselves and may establish
hierarchies.
Life Cycle: Three to six litters
with an average of four per litter per year, starting in March to
September. Gestation of 28 days.
Altricial young. Like all
cottontails, they are synchronous breeders (all members of a population tend
to breed at the same time). WV
studies show 18% of females bred in the first year, while males were not able
to breed until the following season. Life
span of 3 - 4 years.
Nest: Similar to eastern
cottontail.
Tracks: Similar to Eastern
Cottontail.
Scat: Similar in shape to "M
& M’s"; about 3/8" in diameter.
Remarks:
W/H and NAS calls this the Allegheny cottontail.
Smaller than the eastern cottontail, commonly with a black patch
between the ears, which are shorter and rounder than the eastern cottontail
and a greater amount of black on the back. Unlike the eastern cottontail, the
Appalachian cottontail undergoes only one late summer molt.
A WVA
DNR staff member says the Appalachian cottontail is abundant in clear cuts of
higher elevations in WVA, including Dolly Sods and Spruce Knob.
They love dense heath protection. (Mentioned Mower tract, clear cut
15 years ago, now thick with 8' spruce and thick with Appalachian
cottontails.)
Hybridization
occurs with the eastern cottontail and New England cottontail at overlapping
ranges. The New England cottontail (Sylvilagus
transitionalis) has recently been split from the Appalachian cottontail
(1992). Although they both have very similar mountain habitat, they are
allopatric (don't live in same area), so interbreeding cannot be tested. When
captured, the Appalachian cottontail is more aggressive than the eastern
cottontail. However, in the wild, it is the eastern cottontail that
out-competes the smaller and less aggressive Appalachian cottontail. The New
England cottontail is restricted to boreal habitat in Maine, New Hampshire,
Vermont, Massachusetts, Connecticut, Rhode Island and New York as far west as
the Hudson River.
SNOWSHOE
HARE (Lepus
americanus) (hare; from America)
Appalachian
Region Distribution:
Confined to the higher elevations of the Appalachians as far south as the
Allegheny mountain range into TN in disjunct populations (no
documentation of these recorded in the Smokies, although some authors indicate
that it was a former resident). See remarks for details of distribution.
In 1989, 26 hares trapped in West Virginia were released with radio collars in
the Laurel fork region of Highland County of Virginia. Twenty-four survived an
average of 23.8 days post release. They were lost primarily to
predation. They are not known in Maryland or North Carolina.
Continental Range:
Throughout Canada, extending south along the Rockies and Appalachians.
Four subspecies are recognized.
Abundance: Somewhat common
in good habitat, but decreasing in numbers due to deforestation and increase
in white-tailed deer population (reducing available habitat and competition
for food). Captured Canadian hares have been released in VA and MD, although
apparently not very successfully. In MD, no individuals have been
taken in the last 30 years. See remarks below for the status of
the snowshoe population in WV and VA.
Population Density: 1-5/acre.
Densities in
the Appalachians are probably highest in early succession forest stages after
fires and clear cuttings. The Appalachian region populations do not tend to exhibit the cyclic nature
found in more boreal habitats. Stephenson suggests that the cyclic
nature of the northern populations is a result of the extensive uniform
vegetation of aspen, alder and spruce found in the north, dictating a uniform
foraging habit among the hares. The broken forests, thus diverse
vegetation of the Appalachians, results in varied food sources of our hare
populations, thus eliminating any mass population effects. (Canadian
populations exhibit 6 to 13 year
population cycles, averaging ten years. An Alberta study has found population densities ranging from
.1/acre in low years to 4/acre in high years during a 16-year period. Nowak
reports a northwestern Canadian study that found a range from 6/square mile to
3,380/square mile, and even 10,400/square mile. These cyclic patterns have been explained as an interaction between
hares and their food supply, followed by a hare-predator interaction.
Specifically, when the shortage of vegetation ultimately causes a
population crash, the predators reduce the populations below the level
dictated by limiting vegetation alone, increasing the drop of hare numbers.)
Size and Molt: Head and body
13.5 - 18.5 inches; 2.2
- 5.0 pounds,
averaging 2.8 pounds.
Females are slightly larger than males. The
only lagomorph that changes pelage color.
Two molts, with the winter molt taking 70 to 90 days beginning in
October and being complete
in December; the spring molt being complete in May. Not only a defensive aid,
the hollow white hairs, without the pigment melanin, have more air spaces
within the hairs and thus has greater insulation. Snowshoe hares' white winter pelage has 27% better insulative
qualities than the summer brown coat. The
molts are triggered by day length. Populations of a subspecies of L.
americanus (oregonus and washingtonii) in the Pacific Northwest,
where snow does not generally cover the ground, do not turn white in winter.
Some melanistic hares in the Adirondack Mountains remain black all
year.
Mammae: Three pair.
Habitat: This is a forest species,
never far from dense woods, including swamps and thickets. Prefers coniferous
forests. Often found in dense second growth beech/birch/maple forests and young
spruce stands of WV. Rhododendron
and mountain laurel thickets are its habitat in the southern mountains.
Active Period: Largely nocturnal and
crepuscular. Active
year-round. Sits in "form" during the day, located in bushes, or
under logs or stumps.
Diet: Herbaceous plants in summer,
twigs in winter. Maurice Brooks (1955) found snowshoe hares prefer southern
highbush cranberry, but also fed on rosebay rhododendron, red spruce, and
hemlock in West Virginia. Unlike most lagomorphs, Brooks also found that
the snowshoe hare is fond of meat and
will eat carrion, especially in winter (he found two feeding on a deer
carcass). Apparently, occasionally a nuisance to trappers by stealing
bait. Diet closely corresponds to that of
white-tailed deer, with direct competition likely in times of high pops/low
food resources. Hares
practice coprophagy, ingesting soft, mucus-covered pellets directly from the
anus, high in proteins and Vitamin B.
Home Range: 15 - 25 acres,
dependent on population density and vegetative cover.
A male’s territory typically overlaps that of several females and may
or may not be larger than the females home range. A
Montana report finds an overall home range of about 25 acres for males and 19 acres for
females and a Colorado/Utah study found 20 acres for both sexes.
Social Structure: Solitary, but
will tolerate others in feeding areas.
Novak reports that this hare is social, with several adults often living in
close proximity and sharing the same forms. Novak further states as many
as 25 hares have been seen in a clearing at night. Known
to exhibit elaborate courtship behavior during the breeding season, including
much fighting between both bucks and between bucks and perspective doe mates.
Females have been known to be injured by the overly-excited kicking and biting
of the testosterone-laden males. Premating activities include both sexes jumping while urinating on its
mate. (Note information presented in discussion of the Leporidae family
above)
Life Cycle: In this study area, on
the southern limits of the range, two to three
litters, with three per litter being common. Breeding
begins in March with broods occurring from April to August. Higher numbers
of litters (3) and young per litter, averaging 6.5 in Michigan, are found in the
central portion of the hare’s range. Numbers of litters at the
northern limits of the range are smaller (2), but litter size increases (4-5). First
litters of newly mature females are the smallest. It has
been found that largest litters result after winters of greatest snows,
presumably due to the increased depth allowing the hares to reach higher for the younger
green nutritious branches. Females are
seasonally polyestrous, with a gestation
period of 36 days. Precocial young (born active and alert, fully haired
with open eyes) are able to hop on their first day, and are weaned in 25 to 28
days. Mothers are characterized
by postpartum estrus and are often impregnated within a day after giving birth. Until weaned, the "leverets" hide separately (on their
own, or by the mother; depends on who you read)
during the day, returning to the nest in the evening for one nursing, which
only lasts for 5 - 10 minutes. Young
Lepus usually do not breed within their first calendar year of
life. Life span of 3 - 5 years, although probably not more than 15% survive
to breed during more than one season.
Dens/Nest: Snowshoe hare do not dig or occupy burrows, relying on their
speed to escape danger. Nor do they make nests, even for birthing; rather, depressions (forms) are made. Sits in thickets during the
day.
Tracks: Hindprints 4-5"
long. Straddle about 6". Like a large rabbit, with
the rear feet placed just in front of the front feet. Normally, the front feet
will be oriented in a diagonal manner, while squirrels will have their front
feet aligned straight; perpendicular to it’s direction of travel. Has a well
worn system of trails in it's range. Many other animals use these trails,
especially in winter when the snow is hard packed from the hare's travels.
Scat: Similar in shape to "M
& M’s"; about 1/2" in diameter.
Remarks: One of the smallest of the hares, and the only eastern hare, also called the varying hare. Larger than the cottontails, with much larger hind feet, adapted for running on snow. Hares will run in circles when frightened, returning to the original site. Known to leap 12 feet at a bound and run at 30 mph. Known to take "dust baths".
Populations in the Pacific Northwest, where snow does not generally cover the ground, do not turn white in winter.
Populations seem to be declining in the southern Appalachians.
Pennsylvania has snowshoe hare populations limited to the state's mountainous regions, with the exception of the SW PA Appalachian plateau, where it is rare. It's habitat is ridges and slopes of mountain laurel, rhododendron and hemlock.
West
Virginia has a disjunct population, restricted to spruce and northern hardwood
forests above 3,000 feet. Snowshoe hare
range in the Allegheny Mountains of West Virginia generally extends north to
the vicinity of Mt. Storm Lake, Grant County; to the east
the range follows the main Allegheny Mountain to the south in the vicinity of
U.S. Route 250; to the west, starting as far south as Cold Knob in Greenbrier
County, following the west side of the higher elevations of the Elk River,
Greenbrier River, Williams River, and Cheat River Watersheds in Pocahontas,
Randolph, and Tucker Counties. Seems well established in
all high elevation areas of snow cover and brush.
Will be found in snow covered spots when snow cover is limited.
Summer range is the same. Habitat
varies from open to very closed.
In
Virginia, historic habitat closely coincided with the red spruce forests, now
depleted. Current habitat is
second growth birch/red maple forests with a significant and dense shrub
layer. Such habitats are
declining as secondary growth woods are maturing, limiting the shrub layer. Audubon and Bachman were unsuccessful in their attempts to
confirm the existence of snowshoe hare in VA in 1846. Efforts in the 1960’s and 70’s to introduce nonnative hares
from New Brunswick were, fortunately, unsuccessful.
Beginning in 1989, a restocking program using native hares from WVA
introduced 26 hares to the Laurel Fork area in the GW National Forest.
Apparently, none survived, due to predation by bobcats and other
predators. By 1991, no more than a few dozen hares existed in a 15 square mile
area in northwestern Highland County.
At that time, it was acknowledged that habitat management is urgent and
critical for snowshoe hare in Virginia. It
was also acknowledged (in 1991) that, even with a crash program to improve
habitat, the snowshoe hare probably will disappear from Virginia in the next
decade.
The
mating behavior of the snowshoe hare is unique in that hares will jump in
front of prospective mates and commonly urinate on their partners during
premating activities.
Between 200,000 and 400,000 hares are killed annually by hunters in Michigan alone, with any one years' harvest reflecting the population level.