From:
ASSESSMENT OF SPECIES DIVERSITY IN THE MIXEDWOOD PLAINS ECOZONE
MAMMALS
Andrew B. T. Smith Department of Zoology
University of Toronto
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Donald A. Smith Department of Biology Carleton University
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Ontario and Quebec were totally covered with ice during the last glaciation. Deglaciation
was followed by gradual post-glacial repopulation of these two provinces (and others)
by mammals from source areas in the United States. Thus most range expansions were from south to north east of the Great Lakes.
The mammalian fauna of the Mixedwood Plains Ecozone has been steadily changing since
deglaciation about 10 000 years ago. During this period a succession of species
assemblages has moved through this ecozone as the climate warmed. Several of the
larger mammal species known from this area became extinct during this period of change.
These included giant beavers, woolly mammoths, mastodons and species of
deer and bison (Harington, 1989). Throughout this period there have been steady,
gradual changes in the biodiversity of the Mixedwood Plains Ecozone, but the most rapid changes
have occurred over the last 300 years.
The best sources of information
on the ranges of the mammals of the Ontario and Quebec parts of this ecozone
are Peterson (1966) for both parts; Dobbyn (1994) and Peterson (1957) for
Ontario; and Prescott and Richard (1982) for Quebec. Currently in the
Mixedwood Plains Ecozone there are about 59 species of mammals in 44 genera
and 16 families. This does not include four species recorded in this
ecozone, but not established as part of its mammal fauna. An Evening Bat
(Nycticeius humeralis) accidently occurred in the Lake Erie Lowland
Ecoregion once. Black Rats (Rattus rattus), Coypus (Myocaster
coypus), and Domestic Ferrets (Mustela putorius) have all been
introduced but have not persisted. Although the species richness of mammals
has increased since European settlement, biodiversity has decreased in the
Mixedwood Plains Ecozone through the reduction in population size of many
ecologically important species and the complete disappearance of others.
Wolverines, Cougars and Wapiti have all been extirpated from this ecozone.
Many species of mammals have been extirpated from much of their former
ranges in this ecozone because of destruction of forest habitat,
over-harvesting of pelts by fur trappers, over-hunting, and persecution of
predators. Southwestern Ontario is an area of special concern because of
the permanent conversion of most forests to agricultural land; this has
resulted in a dramatic decrease in mammalian biodiversity. The loss of some
native species has been coupled with increases in several new species
through range expansion or direct introduction from other ecozones. The new
species are typically generalists that have adapted to living in disturbed
habitats.
Our knowledge of the status of mammal populations in the Mixedwood Plains Ecozone
is nowhere near complete. The status and complete distribution are known for only
a few species monitored today because of their economic importance. The status
of a few other species has been examined by the Committee on the Status of Endangered
Wildlife in Canada (COSEWIC); its status designations will be mentioned later in the
species accounts. Monitoring programs should be established to determine the status of
ecologically important species for proper biodiversity assessments of this ecozone.
Many small mammals such as shrews, moles, bats, squirrels, mice, and voles could easily
be monitored with existing techniques. Larger mammals would be more difficult to
monitor but there are effective methods available. Large mammalian predator populations
should be monitored as indicators of ecosystem health. Historically in the Mixedwood
Plains Ecozone predator populations have declined most dramatically because of human
disturbances.
The mammals of the Mixedwood Plains Ecozone can be divided into five groups based
on their overall ranges. One group of 14 species has a 'northern distribution' (Fig.MM-1.1);
these species are found mainly in the boreal ecozones and adjacent montane
ecozones of North America. The Mixedwood Plains Ecozone represents the most southern
part of their ranges in eastern Canada. The second group consists of 10 species
with a 'southern distribution' (Fig.MM-1.2); these species reach or near the most
northern parts of their ranges in this ecozone. This group is found mainly in the eastern
United States in broad-leaved forest habitats. The third group consists of 31 species
with a 'widespread distribution' whose ranges extend over much of North America (Fig.MM-1.3).
The much smaller fourth group contains three species with a 'Mixedwood
Plains Ecozone distribution'. These species have a relatively large proportion of
their ranges within the Mixedwood Plains Ecozone (Fig.MM-1.4). The fifth group
consists of four 'introduced' species. The following species accounts also include
three species that no longer occur in the Mixedwood Plains Ecozone. They are included
because they were recently extirpated as a result of human disturbance.
Order Marsupialia: Family Didelphidae - opossums
Didelphis virginiana southern distribution
The Virginia Opossum is a southern species with a range that has recently expanded
into the Mixedwood Plains Ecozone of Canada. The clearing of forests and maintenance
of agricultural land in southwestern Ontario has benefitted this species. Before
the widespread destruction of the forests of this ecozone the Virginia Opossum did not
occur in eastern Canada.
Order Insectivora
All species of shrews and moles are important ecologically as consumers of invertebrates.
Stable shrew and mole populations are vital to the regulation of populations of
ground-dwelling invertebrates, some of which are considered forest pests. Some of
these mammals are difficult for an untrained individual to identify. Shrews and moles
are also secretive and spend much of their time underground so monitoring these populations
requires trained individuals using special trapping techniques.
Family Soricidae - shrews
Sorex cinereus widespread distribution
The Cinereous Shrew is a northern species with a range throughout most of Canada and
the northern United States. This is probably one of the most abundant mammals of
the Mixedwood Plains Ecozone. Cinereous Shrews are found in many different habitats
from fields to forests. Their populations within the ecozone are probably stable but
because of a lack of monitoring data it is impossible to be certain.
Sorex fumeus Mixedwood Plains distribution
The Smoky Shrew has a much smaller range than the Cinereous Shrew. The Mixedwood
Plains Ecozone represents a large part of the Smoky Shrew's total range. For that
reason particular importance should be placed on monitoring this species within the
Mixedwood Plains Ecozone. Because the Smoky Shrew is usually found in damp forests, it
is noticeably absent from extreme southwestern Ontario, most of which has been converted
to agricultural land. Very little is known about the ecology and population status
of this shrew.
Sorex hoyi northern distribution
The Pygmy Shrew is a northern species found through much of Canada. Very little is
known of its biology or population status. In the Mixedwood Plains Ecozone the Pygmy
Shrew is found in a variety of habitats and has a sporadic distribution with naturally low population levels. The absence of this shrew from southwestern Ontario may
be attributed to both the destruction of its natural habitats in that area and the
absence of source populations for recolonization from the south.
Sorex palustris northern distribution
The American Water Shrew is another northern species that reaches part of its southern
limit in the Mixedwood Plains Ecozone. This shrew is always found near water and
forest cover. Because of the semi-aquatic nature of this shrew it is very hard to
catch; therefore little is known about its population status. It is likely decreasing
because of the removal of forest especially in southwestern Ontario.
Blarina brevicauda widespread distribution
The Northern Short-tailed Shrew is common in a wide range of habitats in the Mixed
Wood Plains Ecosystem. This shrew occurs across much of eastern North America with
the Mixedwood Plains Ecozone being central to its range. Populations of this species
can reach high densities in some areas and can devastate insect and small-mammal communities
(Peterson, 1966). It is likely that this species maintains a stable population within
the Mixedwood Plains Ecozone.
Cryptotis parva southern distribution
In the Mixedwood Plains Ecozone the Least Shrew is known only from Long Point, Ontario.
It has been suggested that this population of Least Shrews originated from individuals
that rafted across Lake Erie. An investigation of the grassy dune habitats near Lake
Erie might augment our limited knowledge of the Least Shrew in our ecozone, or, on the
other hand, might suggest that the small population there has been extirpated.
Family Talpidae - moles
Parascalops breweri Mixedwood Plains distribution
Because of the Hairy-tailed Mole's (Fig. MM-1.5) limited distribution, the Mixedwood Plains Ecozone
represents a substantial portion of its range. Although the biology and
distribution of this species are poorly known, sandy, dry soil with vegetation cover
seem to be preferred (Peterson, 1966). The maintenance of a stable population of Hairy-tailed
Moles within the Mixedwood Plains Ecozone is probably vital to the success of this
species. Appropriate measures should be taken to monitor its populations within this ecozone.
Scalopus aquaticus southern distribution
The Eastern Mole's Canadian distribution is limited to Essex County in the Lake Erie
Lowland Ecoregion in extreme southwestern Ontario. It is also found across the entire
eastern half of the United States. The preferred sandy soil habitat of this mole
is restricted within the Mixedwood Plains Ecozone. Even though the restricted Canadian
range of the Eastern Mole is spatially insignificant compared to the vast range south
of the border, it's a species meriting special consideration for conserving Canadian
biodiversity. COSEWIC listed Canadian populations of Eastern Moles as vulnerable.
Condylura cristata widespread distribution
The Star-nosed Mole occurs across much of eastern North America including all of the
Mixedwood Plains Ecozone. These moles live in moist bogs, swamps, forests, and meadows
and often forage in water. The Star-nosed Mole is fairly common but the status of the
population is not known because of a lack of monitoring data.
Order Chiroptera
As all bats found in the Mixedwood Plains Ecozone prey entirely on nocturnal and
crepuscular flying insects, they, like shrews and moles, are important ecologically.
Of the eight species of bats found in the Mixedwood Plains Ecozone three are migratory
and five hibernate underground during winter. The migratory species move south out
of this ecozone during the fall so environmental factors in their wintering grounds
may also affect their populations.
The specific techniques required to monitor bat populations would have to be performed
by specially trained individuals. Special training and experience are also needed
to identify bats to species. Because of the complexities of monitoring bat populations
there are very few quantitative data on the status of bat populations within this
ecozone.
Family Vespertilionidae - common or vesper bats
Myotis leibii Mixedwood Plains distribution
The Eastern Small-footed Bat has a relatively small distribution. A high proportion
of this distribution falls within the Mixedwood Plains Ecozone. Little is known
about its biology or population status. Its absence from extreme southwestern Ontario
may be due to the removal of forests from this area as well as the absence of underground
hibernation sites. As this ecozone represents a large part of the total range of
Eastern Small-footed Bats, extra emphasis should be placed on the monitoring and
conservation of this species within this ecozone.
Myotis lucifugus widespread distribution
The Little Brown Bat (Fig. MM-2, Fig. MM-3, Fig. MM-4) is found in much of North America, including the entire Mixedwood
Plains Ecozone. This is one of the most common and best studied bats of
our area. But like all other bats, its overall population status is unknown.
Myotis septentrionalis widespread distribution
The Northern Long-eared Bat is found through much of eastern North America including
the Mixedwood Plains Ecozone. This bat is relatively uncommon and little is known
of its biology although it seems to be found more frequently in heavily forested
areas. The absence of this bat from extreme southwestern Ontario may be due to the removal
of forests in this area and absence of hibernation sites.
Lasionycteris noctivagans widespread distribution
The Silver-haired Bat is a migratory species found over most of North America including
all of the Mixedwood Plains Ecozone. Although this bat is often described as solitary,
maternity colonies of females and young have been found in hollow trees, including one
in the Manitoulin-Lake Simcoe Ecoregion of this ecozone. This species lives
in forested areas along streams and lakes. Like the other bats of this ecozone virtually
nothing is known of its abundance or population status.
Pipistrellus subflavus southern distribution
The Eastern Pipistrelle almost reaches its northern limit of distribution in the Mixedwood
Plains Ecozone. This bat occurs throughout most of the eastern United States and
Mexico. It is usually found near water and forest edges but may avoid large tracts of
unbroken forest (Kurta, 1995). In the Mixedwood Plains Ecozone this bat is most
abundant on the north shores of Lake Erie and Lake Ontario (Dobbyn, 1994).
Eptesicus fuscus widespread distribution
The Big Brown Bat is found all over North and Central America except north of the
boreal forest. This may be the most common bat in the Mixedwood Plains Ecozone because
it occurs in open habitats including agricultural and urban areas (van Zyll de Jong,
1985). Because it is not common in heavily forested areas it is likely that the Big
Brown Bat population has increased over levels present before the destruction of
most of the forests in this ecozone.
Lasiurus borealis widespread distribution
The Red Bat is a migratory species found in the Mixedwood Plains Ecozone for only
half of the year. It is also found in much of the United States and Central America.
The Red Bat is a solitary species found in forested areas near water (Peterson,
1966).
Lasiurus cinereus widespread distribution
The Hoary Bat is another migratory species found in the Mixedwood Plains Ecozone for
only half of the year. This species occurs throughout most of North America and
down to South America. It too is a solitary species found in forested areas near
water (Peterson, 1966).
Order Lagomorpha: Family Leporidae - rabbits and hares
These lagomorphs are more widely recognized than most small to medium-sized mammals
because they are larger in size and often active during the day. They are very important
ecologically as abundant consumers of ground vegetation. Lagomorphs are also key prey
items for many carnivores especially foxes, Coyotes, large weasels, and native
cats. Of the three species found in the Mixedwood Plains Ecozone only one was present
before European settlement. That species is the Snowshoe Hare (Lepus americanus)
which has probably declined because of habitat destruction while being replaced
by two new species which prefer open, disturbed habitat. The loss of large mammalian
predators due to over-harvesting and habitat destruction has undoubtedly benefitted
all lagomorphs within this ecozone. Because these lagomorphs are such important links
in the natural food chains of the Mixedwood Plains Ecozone, monitoring populations
would be critical to estimating future trends in biodiversity of this ecozone.
Sylvilagus floridanus southern distribution
The Eastern Cottontail (Fig. MM-5, Fig. MM-6), the only rabbit in this ecozone, is found throughout most
of the United States and into the Mixedwood Plains Ecozone where it just about reaches
its northern limit. This rabbit is typically found in disturbed areas including
open forest, forest edges, agricultural land, and urban areas. The Eastern Cottontail
may have occurred in the Mixedwood Plains Ecozone sporadically long before European
settlement, but they expanded within this ecozone permanently about 1860 (Dobbyn,
1994). Since then range expansion and population increase of this species have been observed
across the Mixedwood Plains Ecozone. Obviously this species has benefitted from
the destruction of most of the forests and the decrease in many large predators in
this ecozone.
Lepus americanus northern distribution
The Snowshoe Hare (Fig. MM-7) is the only lagomorph that occurred in the Mixedwood Plains Ecozone
before European settlement. It is also found across most of the boreal forests of
Canada. Unlike the other two lagomorphs found in this ecozone the Snowshoe Hare
prefers heavily forested habitats away from human disturbance. Coniferous forests, especially
White Cedar swamps, are where they occur in our ecozone. The removal of most forests
from the Mixedwood Plains Ecozone has resulted in declining populations and range of this species.
Lepus europaeus introduced
The European Hare was introduced to North America near Brantford, Ontario in 1912
(Dobbyn, 1994). The European Hare prefers cultivated fields and disturbed areas;
this allowed it to expand its range and population through most unforested parts
of the Mixedwood Plains Ecozone in Ontario. Owing to the lack of monitoring data
the status of its population within the Mixedwood Plains Ecozone is unknown.
Order Rodentia
Rodents are the most diverse group of mammals in the Mixedwood Plains Ecozone with
20 species in 17 genera and five families. Most rodents are small but abundant and
therefore represent a large percentage of the mammal biomass in all terrestrial habitats within this ecozone. Rodents usually consume plant matter but many also prey on
invertebrates. They are preyed upon by foxes, Coyotes, mustelids, hawks, and owls.
Rodents are important links in food webs and have major impacts on the entire ecosystem. Because of their diversity, ecological importance, and abundance in all terrestrial
habitats, rodents are an important group to monitor in an assessment of biodiversity
for any ecozone.
Family Sciuridae - squirrels
Squirrels represent a widely recognized group of small mammals owing to the diurnal
habits and high visibility of most species.
Tamias striatus widespread distribution
The Eastern Chipmunk is found in most of eastern North America including the Mixedwood
Plains Ecozone. This species is common in most dry forest and bushy habitats across
the ecozone. Although the population of Eastern Chipmunks has probably decreased
since European settlement with its preferred mature maple-beech habitat in this ecozone,
it seems to have adapted to some human disturbance and to maintain a stable population.
Marmota monax widespread distribution
The Woodchuck occurs across much of the eastern United States and Canada including
the Mixedwood Plains Ecozone. It prefers open habitat and has increased as the native
forests were destroyed in this ecozone. The elimination of most large predators
through over-harvesting and habitat destruction has also undoubtedly benefitted this species
of ground-dwelling squirrel. The Woodchuck is abundant throughout the Mixedwood
Plains Ecozone.
Sciurus carolinensis southern distribution
The Eastern Gray Squirrel occurs in the eastern United States and almost reaches its
northern limit of distribution in the Mixedwood Plains Ecozone. The pelage
colour is variable, with the two main morphs being gray (Fig. MM-8) and black (Fig. MM-9). The black morph
is more common than the gray in the northern part of its range in Ontario and southwestern
Quebec. This squirrel occurs anywhere where there are broad-leaved trees including
in cities. A range expansion northward has been observed over the past century.
The Eastern Gray Squirrel has apparently benefitted from human alterations to the Mixedwood
Plains Ecozone.
Sciurus niger introduced
The Fox Squirrel was introduced from the eastern United States to Pelee Island in
Lake Erie. This isolated population is of little importance to the biodiversity
of the Mixedwood Plains Ecozone. COSEWIC has declared it 'not at risk'.
Tamiasciurus hudsonicus northern distribution
The American Red Squirrel (Fig. MM-10) occurs over most of northern North America including the
Mixedwood Plains Ecozone. This squirrel can be found anywhere there are coniferous
trees, even including many urban areas. Although the American Red Squirrel is abundant
and seems to have a stable population in this ecozone it is unknown what the population
levels were in the past.
Glaucomys sabrinus northern distribution
The Northern Flying Squirrel occurs in most boreal and adjacent montane regions of
North America south of the treeline. The Mixedwood Plains Ecozone represents the
most southern part of its eastern range other than in the Appalachian Mountains.
Over most of its range it prefers coniferous forests. The population status of these nocturnal
squirrels is unknown because of a lack of monitoring data. Its population levels
may be affected by the population of the more southerly ranging Glaucomys volans.
Long- term monitoring would provide information on the dynamics of these two species.
Glaucomys volans southern distribution
The Southern Flying Squirrel is found throughout the eastern United States and reaches
almost the northern part of its distribution in the Mixedwood Plains Ecozone. The
preferred habitat of this squirrel is deciduous forests. Because the two flying
squirrel species are difficult to distinguish without training, observational data are
scarce, but the Southern Flying Squirrel appears to have recently expanded its range
northward in Ontario and southern Quebec. Population monitoring by trained individuals
would reveal the population and distribution status of the flying squirrels. COSEWIC
listed populations of Southern Flying Squirrels as vulnerable in Canada.
Family Castoridae - beavers
Castor canadensis widespread distribution
The North American Beaver is found virtually everywhere in North America including
the Mixedwood Plains Ecozone. Beavers prefer forested areas with slow-moving water.
After the destruction of this habitat they no longer occur in extreme southwestern
Ontario (Dobbyn, 1994). Extensive habitat destruction and over-harvesting of beavers
almost caused their extirpation from this ecozone about a century ago. Management
of their populations including the prevention of further over-exploitation allowed
them to recover to the relatively high levels they are at today.
Family Muridae - rats, mice, and voles
Although they are not as easily seen as some other mammals, these rodents are by far
the most abundant of mammals in their habitats within the Mixedwood Plains Ecozone.
Population levels are comparable only to those of some of the shrews. It is therefore important to study the population dynamics of these species to interpret some of
the changes in biodiversity within an ecozone.
Peromyscus leucopus southern distribution
The White-footed Mouse is found across the eastern and central United States and reaches
almost the northern edge of its eastern distribution in the Mixedwood Plains Ecozone.
This mouse is most common in broad-leaved forests and is abundant across the entire ecozone. The White-footed Mouse is very closely related to Peromyscus maniculatus,
the Deer Mouse, which can co- exist in the same forest. Distinguishing between
these two species is difficult and must be done by trained individuals who must capture
them and make measurements and critical observations. Although this species is abundant its population status is unknown because of the lack of data and difficulty in
identification.
Peromyscus maniculatus widespread distribution
The Deer Mouse is found through much of North America including the Mixedwood Plains
Ecozone. Two subspecies of Deer Mice live in this ecozone, P. m. bairdii
in the grassland of the Lake Erie Lowland Ecoregion and P. m. gracilis
in the forests of the rest of the ecozone. Although this species is abundant across
the Mixedwood Plains Ecozone, its population status is unknown. It is possible that
Deer Mouse populations in forests are affected by populations of closely related
White-footed Mice but because of the difficulty in identification and a lack of data this
is unknown.
Clethrionomys gapperi northern distribution
The Southern Red-backed Vole is found throughout boreal and adjacent montane areas
of North America including part of the Mixedwood Plains Ecozone where it reaches
its southern limit in Canada. This species occurs in moist coniferous and mixed
forests. Although the Southern Red-backed Vole can be very abundant in this ecozone its population
status is unknown.
Microtus pennsylvanicus widespread distribution
The Meadow Vole is found throughout most of North America except the extreme southern
United States. This vole is abundant throughout the meadows and open areas of the
Mixedwood Plains Ecozone. It has benefitted from the destruction of most of the
forest habitats within this ecozone and has probably increased in population size over
the past few centuries.
Pitymys pinetorum southern distribution
The Woodland Vole ranges across most of the eastern United States and reaches the
northern tip of its distribution in the Mixedwood Plains Ecozone. Within this ecozone
the Woodland Vole is found only in part of the Lake Erie Lowland Ecoregion in Ontario
and in the St-Laurent Lowlands Ecoregion of southern Quebec just north of the border
with Vermont. This vole seems to prefer mature broad-leaved forest habitat, which
has been almost entirely destroyed in the Mixedwood Plains Ecozone. It is very likely
that Woodland Vole distribution and population size have decreased in this ecozone in
historic times along with their native habitat. Monitoring the small populations
isolated in small forest remnants would be highly recommended for a biodiversity
assessment of this ecozone.
Ondatra zibethicus widespread distribution
The Muskrat is found throughout most of North America including the Mixedwood Plains
Ecozone. They are found in ponds, streams, lakes, and marshes with aquatic vegetation.
The population of Muskrats in this ecozone seems to be stable even though it continues to be trapped heavily for pelts.
Synaptomys cooperi widespread distribution
Although the Southern Bog Lemming is found throughout the central part of eastern
North America, the Mixedwood Plains Ecozone is in the centre of its distribution.
The habitat of this lemming is in bogs, meadows, and forests with deep litter -
either damp or dry. This species is uncommon in this ecozone especially relative to the abundance
of other species in this family. Owing to the lack of monitoring data on this species
very little is known of its population status and habitat requirements in the Mixedwood Plains Ecozone. Populations have likely declined due to habitat destruction
and possibly competition with Meadow Voles (Kurta, 1995).
Rattus norvegicus introduced
The Norway Rat was introduced to North America about 1775 and since has spread across
the continent to most places with human settlements, including the Mixedwood Plains
Ecozone (Kurta, 1995). This species is only found associated with human settlement,
not in 'natural' habitats. Were Norway Rats ever to invade the latter and to compete
with native species, they could potentially have a negative impact on the biodiversity
of this ecozone.
Mus musculus introduced
The House Mouse was introduced to North America by early European settlers and has
spread across the continent to most places with human settlements, including the
Mixedwood Plains Ecozone. This species, like the Norway Rat, is found mainly in
areas of human settlement now but potentially could have a negative impact on the
biodiversity of this ecozone.
Family Dipodidae - jumping mice
The jumping mice are not as diverse or abundant as the murids in the Mixedwood Plains
Ecozone but they are an important part of the natural ecosystems of this area. These
rodents are hibernators and relatively good burrowers and use these abilities to
exploit different niches than other small rodents in this area.
Zapus hudsonius widespread distribution
The Meadow Jumping Mouse is found through the boreal regions of Canada and much of
eastern North America, including the Mixedwood Plains Ecozone. This species is
most common in moist meadows but is also found in a variety of other habitats. The
Meadow Jumping Mouse seems to have a stable population in this ecozone but this is uncertain
because of a lack of monitoring data.
Napaeozapus insignis northern distribution
The Woodland Jumping Mouse inhabits the Boreal Shield and Atlantic Maritime Ecozones
and adjacent montane areas of eastern North America. The Mixedwood Plains Ecozone
is the southern tip of the part of this range in Ontario. This species is found
in mature forests near water and has probably decreased in historic times owing to habitat
destruction. The current status of the population seems to be stable but this is
uncertain because of a lack of monitoring data.
Family Erethizontidae - New World porcupines
Erethizon dorsatum widespread distribution
The Porcupine (Fig. MM-11) is found through much of North America including the Mixedwood Plains
Ecozone. This species lives in forests, particularly coniferous forests. Porcupines
have been extirpated from most of southwestern Ontario because of habitat destruction. Although Porcupines are still common in many areas, they seem to be sensitive to
deforestation and cannot live in small, isolated woodlots. Monitoring of this species
would be recommended in a biodiversity assessment of the Mixedwood Plains Ecozone.
Order Carnivora
Carnivores represent the second most diverse order of mammals in the Mixedwood Plains
Ecozone with 16 species in 11 genera and five families present today. Many of these
carnivores are relatively large and prey upon other living animals so they typically need large home ranges and have low population densities. A few species of carnivores
have adapted to live in disturbed areas and have benefitted from the destruction
of most of the habitats native to this ecozone, but most species have decreased dramatically. Most of the native carnivores in the Mixedwood Plains Ecozone have been extirpated
from some or all of their former ranges. Many carnivores in this ecozone are economically
valuable to the fur trade. Moreover, carnivores are ecologically important because they can influence the abundance of other vertebrates. A healthy carnivore
population can help to prevent herbivore population explosions where levels increase
until all the available vegetation has been consumed and the habitats are badly damaged. This type of system was present before the destruction of most native habitats
and human persecution and over-harvesting of carnivore pelts began. Today several
species of carnivores are missing; this negatively affects the ecosystems and therefore
biodiversity in the Mixedwood Plains Ecozone. Some carnivores are important reservoirs
of rabies in this Ecozone.
Family Canidae - foxes, wolves, and allies
Canis latrans widespread distribution
The Coyote (Fig. MM-12) is found throughout most of North America including the Mixedwood Plains
Ecozone. This species was historically found in the prairies but has greatly extended
its range eastward and southward, reaching this ecozone in the early 1900s (Peterson, 1966). The Coyote is found in disturbed habitats such as agricultural land and
clearcuts. It is closely related to Canis lupus
and domestic dogs and is known to hybridize with both. The recent population and
distribution increase of the Coyote is still in a state of flux so monitoring programs
of this and related species should begin as soon as possible to document this change.
Canis lupus northern distribution
The Gray Wolf is found throughout most of Canada and reaches the southern part of
its distribution in the Mixedwood Plains Ecozone. This species was probably once
common in the Mixedwood Plains Ecozone and found throughout North America but it
has been extirpated from most of its former range including most of this ecozone. Destruction
of habitat and persecution by humans have resulted in the almost complete disappearance
of the Gray Wolf. Now the Gray Wolf can be found in the Mixedwood Plains Ecozone
only along the northern edge. Population monitoring and conservation programs are
strongly recommended for this ecologically and aesthetically important but disappearing
native species.
Vulpes vulpes widespread distribution
The Red Fox is found across most of North America including the Mixedwood Plains Ecozone.
This species can be found in many different types of habitats except large tracts
of mature forest. The Red Fox is very common throughout this ecozone and has benefitted from the destruction of most of the native habitat here. The population is
stable and possibly increasing.
Urocyon cinereoargenteus southern distribution
The Gray Fox is found throughout much of the United States and reaches the northern
tip of its distribution in the Mixedwood Plains Ecozone. This fox prefers forested
areas and was extirpated from this ecozone from the time of European settlement until
the 1930s (Peterson, 1966). Although the range is slowly expanding into southern Ontario
and extreme southern Quebec from the south, the Gray Fox is very uncommon and has
been designated as rare on the Ontario status list (Dobbyn, 1994), and as vulnerable in Ontario
and Quebec by COSEWIC.
Family Ursidae - bears
Ursus americanus widespread distribution
The American Black Bear (Fig. MM-13) occurs throughout much of non-arctic Canada and the United
States including the Mixedwood Plains Ecozone. This species prefers forested areas
and was once common throughout most of North America. Destruction of its habitat
and the continued over-hunting by humans are the main causes of its decline. This species
has been extirpated from much of this ecozone especially where forests have been
permanently removed. Population monitoring and conservation programs are strongly
recommended for the Black Bear.
Family Procyonidae - raccoons
Procyon lotor widespread distribution
The Northern Raccoon (Fig. MM-14) is found throughout much of North America including the Mixedwood
Plains Ecozone. This species is omnivorous and lives in many different habitats
including urban areas. The Raccoon population is increasing in this ecozone as it
adapts to human disturbance. This abundant carnivore should be monitored as the population
seems to be rapidly changing.
Family Mustelidae - weasels and allies
Martes americana northern distribution
The American Marten is found throughout the boreal forest and some adjacent montane
areas in the west; it occurs in the northern edge of the Mixedwood Plains Ecozone
where it reaches part of its southern limit. This weasel prefers large tracts of
coniferous forests but also inhabits mixed forests. The American Marten once ranged across
the entire Mixedwood Plains Ecozone but has been extirpated from almost all of it
because of deforestation and over-harvesting of pelts. The American Marten has disappeared from many areas where the rodents it eats are still abundant. Population monitoring
and conservation programs for the American Marten are highly recommended for this
economically and ecologically important carnivore.
Martes pennanti northern distribution
The Fisher has a distribution and habitat requirements similar to those of the American
Marten. The Fisher has been extirpated from much of the Mixedwood Plains Ecozone
for the same reasons as the American Marten and similar population monitoring and
conservation programs are recommended.
Mustela erminea northern distribution
The Ermine (Fig. MM-15) is found across most of Canada including the Mixedwood Plains
Ecozone . It is found mainly in forested habitat and tundra. Ermine
populations have probably declined because of habitat destruction but
they are still regularly found in most of the ecozone. Distinguishing
this species from the Long-tailed Weasel (Mustela frenata) can
be difficult for an untrained individual.
Mustela frenata widespread distribution
The Long-tailed Weasel is distributed throughout the United States and some southern
parts of Canada including the Mixedwood Plains Ecozone. This species, although more
tolerant of disturbed habitats, is less abundant than the Ermine in this ecozone.
The dynamics between Long-tailed Weasel and Ermine populations are not clear but warrant
future research.
Mustela vison widespread distribution
The American Mink occurs through much of North America including the Mixedwood Plains
Ecozone. Minks are always found near lakes, rivers, streams, marshes, or the seashore,
even in disturbed areas. This species seems to have a stable population in the Mixedwood
Plains Ecozone.
Gulo gulo northern distribution
The Wolverine was once found throughout Canada and in some of the northern United
States but today it occurs only in northern and western Canada and the northwestern
United States. Wolverines were extirpated from the Mixedwood Plains Ecozone shortly
after European settlement because of habitat destruction and human persecution. The Wolverine
can be found in many types of undisturbed habitats but little else is known about
the biology of this disappearing species.
Taxidea taxus widespread distribution
The American Badger occurs through much of western North America and reaches its eastern
limit in the Lake Erie Lowland Ecoregion of the Mixedwood Plains Ecozone. Badgers
are found in open grasslands and agricultural land, but it is unknown whether they
inhabited the remnant prairie in extreme southwestern Ontario before European settlement.
Even if they did, their small range in this ecozone likely increased eastward after
the forests were destroyed for agriculture. COSEWIC has declared their small population
in Ontario as 'not at risk.'
Mephitis mephitis widespread distribution
The Striped Skunk occurs throughout much of North America except the extreme north.
This species inhabits semi-open and open areas both urban and rural and is abundant
throughout the Mixedwood Plains Ecozone. Skunks have benefitted from the clearing
of the forests in this ecozone and have undoubtedly increased as a result.
Lontra canadensis widespread distribution
The North American River Otter occurs in much of North America including the Mixedwood
Plains Ecozone. This species is highly adapted for an aquatic life and is always
found near lakes, ponds, rivers, streams and oceans. Otters fare poorly in areas
of human disturbance and have become extirpated from southwestern Ontario because of
habitat loss, over-harvesting, and pollution. Monitoring otter populations is recommended
as a biological indicator of the health of aquatic ecosystems.
Family Felidae - cats
Felis concolor widespread distribution
Although the Cougar or Mountain Lion historically occurred throughout the United States
and southern Canada including the Mixedwood Plains Ecozone, its natural distribution
has been greatly reduced. Cougars were extirpated from the Mixedwood Plains Ecozone
over 150 years ago because of habitat destruction and human persecution. The Wapiti
(Cervus elaphus) was probably a major prey item for the Cougar in this ecozone
so their extirpations could probably be linked together. COSEWIC listed eastern
populations of Cougars as endangered.
Lynx canadensis northern distribution
The Canada Lynx is found throughout all of boreal Canada and adjacent montane areas
of the western United States. This species has been extirpated from much of the
southern part of its range including most of the Mixedwood Plains Ecozone. The Canada
Lynx is found in large areas of undisturbed coniferous forest usually where Snowshoe
Hares also occur. The Canada Lynx has decreased along with the Snowshoe Hare in
this ecozone because of habitat destruction and over-harvesting. Population monitoring
and conservation programs are needed for this declining species. Nevertheless, COSEWIC
declared the Canada Lynx as 'not at risk' throughout Canada.
Lynx rufus widespread distribution
The Bobcat occurs throughout most of the United States and some of southern Canada
including part of the Mixedwood Plains Ecozone. This species is found in forested
habitats and is adaptable to some human disturbance. The Bobcat population has been
extirpated from most of this ecozone because of habitat loss and over-harvesting of
pelts. Population monitoring and conservation programs are needed for this possibly
declining species.
Order Artiodactyla: Family Cervidae - deer and allies
Cervus elaphus widespread distribution
The Wapiti (Fig. MM-16) was once found across much of central North America including the Mixedwood
Plains Ecozone. Only small populations still exist today in western North America.
Wapiti were extirpated from this ecozone by habitat destruction and over- hunting
by 1850 (Peterson, 1966). The eastern race C. e. canadensis
is now extinct.
Odocoileus virginianus widespread distribution
The White-tailed Deer (Fig. MM-17) occurs throughout most of the United States and southern Canada
including the Mixedwood Plains Ecozone. This species is found in agricultural land
and other disturbed habitats as well as in forests, especially secondary ones. The
clearing of most of the original forest in this ecozone along with the extirpation
of all natural predators benefitted this species. Populations have been increasing
and the range has been expanding northward since European settlement.
Alces alces northern distribution
The Moose (Fig. MM-18) occurs throughout boreal Canada and in adjacent montane areas in the northern
United States. Moose entered the Mixedwood Plains Ecozone after deglaciation by
moving north around the east end of Lake Ontario from the United States (Peterson,
1957). This species has been extirpated from most of its former range therein because
of forest destruction and over-hunting. It is usually found in coniferous forests
near lakes or streams. Because of the Moose's economic importance, its biology is
well known. A brain parasite found in White-tailed Deer can be harmful to Moose. The
spread of White-tailed Deer northward has therefore been detrimental to Moose populations.
REFERENCES
Dobbyn, J.S. 1994. Atlas of the Mammals of Ontario. Federation of Ontario Naturalists,
Don Mills, Ontario.
Harington, C.R. 1989. Ice-Age Fossils and Vanished Vertebrates. pp. 156-164 in
Legacy: The Natural History of Ontario (ed. J.B. Theberge). McClelland & Stewart Inc., Toronto.
Kurta, A. 1995. Mammals of the Great Lakes Region. Fitzhenry & Whiteside Limited,
Markham, Ontario.
Peterson, R.L. 1957. Changes in the Mammalian Fauna of Ontario. pp. 43-58 in
Changes in the Fauna of Ontario (ed. F.A. Urquhart). University of Toronto Press
for Division of Zoology and Palaeontology, Royal Ontario Museum.
Peterson, R.L. 1966. The Mammals of Eastern Canada. Oxford University Press, Toronto.
Prescott, J. et P. Richard. 1982. Mammifères du Québec et de l'est du Canada. Éditions
France-Amérique, Montréal. 2 volumes.
van Zyll de Jong, C.G. 1985. Handbook of Canadian Mammals. Vol. 2. Bats. National
Museums of Canada, Ottawa.
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