Wild Species 2005: chapter 11

Mammals

Mammal - Any warm-blooded animal of the vertebrate class Mammalia, members of which are characterized by the possession of mammary glands and a four-chambered heart, including human beings, carnivores, ungulates, rodents, whales, etc. - The Canadian Oxford Dictionary.

Photo of two moose standing in water among grasses and shrubs
Photo: Moose (Alces alces) © B. T. Aniskowicz-Fowler

Quick facts

  • There are more than 5000 known species of mammals, divided into 26 orders. The rodents are the largest order of mammals in the world, both in terms of number of species, and number of individuals.
  • A total of 218 species of mammal have been found in Canada, including 169 species ranked in the provinces and territories and 49 ranked in the ocean regions.
  • Since Wild Species 2000, three terrestrial mammals and one marine mammal have been added to the species list. All four additions were due to genetic analyses of existing species.
  • The majority of mammal species have Canada ranks of Secure (64%), but 11% have Canada ranks of Sensitive, 6% have Canada ranks of At Risk and 5% have Canada ranks of May Be At Risk.
  • Of the 210 species that were ranked in both 2000 and 2005, the majority (81%) have retained the rank they were given in 2000. Of the 40 species whose Canada rank has changed, 18% have changed to a Canada rank with a reduced level of risk, 25% have changed to a Canada rank with an increased level of risk and 57% have moved into or out of the Undetermined, Not Assessed or Accidental categories. The majority of these changes were due to new or updated COSEWIC assessments (40%).
  • The world's largest mammal is the Blue Whale, which can grow up to 25 m long and weigh up to 100 tonnes.

Background

From the Atlantic Walrus (Odobenus rosmarus) of the frozen Arctic, to the American Bison (Bos bison) of the prairies, to the Red Squirrel (Tamiasciurus hudsonicus) in your backyard or local park, mammals are a familiar and diverse group found throughout Canada. Mammals are able to endure Canada's varied and sometimes harsh climate because they are warm-blooded (endothermic). This means that mammals are able to keep their core body temperature stable, despite outside temperature fluctuations. Mammals are believed to have evolved from a group of reptiles, called the synapsids, more than 200 million years ago, slightly before the dinosaurs appeared on earth. Since the disappearance of the dinosaurs, about 65 million years ago, mammals have spread and diversified to reach their present, global distribution.

One of the defining characteristics of mammals is the possession of hair, from the short, velvety hair of the Townsend's Mole (Scapanus townsendii), to the thick, shaggy coat of the Muskox (Ovibos moschatus). The most important function of hair is to provide insulation from the cold. For example, the hair of the Arctic Fox (Vulpes lagopus) provides such efficient insulation that they can remain active even at temperatures below -50 °C! Some mammals loose their hair as adults, so they use other methods of insulation. For example, Cetaceans (whales, dolphins and porpoises) which loose their hair soon after birth, are insulated by a thick layer of blubber. Other important uses of hair include camouflage (e.g. the white, winter coat of the Snowshoe Hare, Lepus americanus) and communication (e.g. the White-tailed Deer, Odocoileus virginianus, uses its white tail to flash a danger signal as it runs from a predator). There are two main types of hair, underfur and guardfur, each with its own function. The thick, soft underfur traps a layer of warm air to insulate the body, while the guardfur acts to protect the underfur. The long, soft underfur of the Muskox is one of the most luxurious and expensive natural fibres in the world.

All female mammals possess mammary glands, which produce milk to feed their young. Milk is rich in proteins and fat, and provides the young with the nutrients and energy they need to develop and grow. While they depend on their mother for milk, the young develop social behaviours and learn about their environment, including which foods are good to eat and how to find them. Some mammals, such as the Caribou (Rangifer tarandus), give birth to precocial young, which are well developed and can run almost immediately after birth. Young Caribou stagger to their feet less than an hour after birth, and can run fast enough to keep up with the herd within the first day or two of life. In contrast, altricial young are born helpless, often blind, and with very limited mobility. For example, Eastern Grey Squirrels (Sciurus carolinensis) are born naked and toothless, and their eyes and ears are scarcely visible. It takes over a month before their eyes begin to open, and almost two months before they venture outside the nest.

Some of Canada's most distinctive mammals are those that live in the Arctic tundra, including the Polar Bear (Ursus maritimus), Arctic Fox, Caribou, Muskox, and several different types of lemming. While some of these mammals, such as the Caribou, migrate south during the winter, many are resident on the tundra year round. Arctic mammals show many adaptations to the extreme cold, including thick fur coats and high metabolic rates. Several Arctic mammals, such as the Muskox and Polar Bear have evolved a large size and compact shape, to reduce heat loss. Small mammals, such as the Northern Bog Lemming (Synaptomys borealis) spend the winter under the snow. Deep snow acts as an insulating layer, protecting the lemmings from extreme surface temperatures. Many Arctic mammals keep their extremities at temperatures close to freezing while their core body temperature does not fluctuate. For example, the temperature of a Caribou's legs can be as much as 100C cooler than its core body temperature. This is accomplished by a special arrangement of blood vessels that allow the warmth of the blood being pumped to the extremities to heat the blood returning to the core (this system is called counter-current heat exchange). Only one Arctic mammal, the Arctic Ground Squirrel (Spermophilus parryii), undergoes true hibernation, during which its body temperature drops far below normal.

Status of knowledge in Canada

In general, mammals in Canada have been well-studied, and the basic biology and physiology, distribution and ecology of many mammal species are well understood. In recent years, technological advances including satellite telemetry and new genetic tools have been used to further improve knowledge of Canadian mammals. However, there remain challenges that make studying mammals in the wild difficult, including nocturnal or secretive behaviour, remote distribution, difficulty in handling wild mammals and the vast distances covered by some large mammals. In addition, many marine mammals can be difficult to study due to the long time spent under water, and the short time spent at the surface.

A major focus of mammalogy in Canada has been studies of large mammals, such as Caribou, Wapiti (also known as elk, Cervus canadensis) and Polar Bears. Large mammals are important to study because of their economic value, potential for conflict with humans and their importance in the ecosystems in which they live. For example, recent research in Banff National Park has shown that by controlling the Wapiti population, Grey Wolves (Canis lupus) have an indirect impact on the local vegetation structure and bird communities. In areas of high Grey Wolf density, there are fewer Wapiti, more regenerating vegetation, more warblers and fewer sparrows. Studies like this demonstrate the importance of large mammals in shaping their local ecosystems.

Tracking mammals at sea is a difficult task, and can limit research on deep-sea marine mammals, but new technology, including satellite tracking, satellite remote sensing and acoustic remote sensing, is helping to improve knowledge in this area. For example, Blue Whale (Balaenoptera musculus) migration and habitat use has been followed using acoustic and satellite remote sensing, allowing continuous, large-scale, spatial and temporal tracking of Blue Whale movements for the first time.

In general, mammals that are not considered economically or culturally important (such as shrews, family Soricidae), have not been studied as well as large, charismatic or economically important mammals, like the Polar Bear or Caribou. For example, bats (order Chiroptera) are generally less well-studied and less well understood than many other mammal groups, and the distribution, ecology and life history of some bats in Canada is still poorly known. However, new studies are starting to close this gap. For example, recent surveys in Nova Scotia discovered Canada's first known breeding colony of Eastern Pipistrelles (Pipistrellus subflavus). Other recent bat studies have focussed on habitat use, echolocation, diet and thermal ecology of bats.

Richness and diversity in Canada

There are nine orders of mammals in Canada, of which the rodents (Order Rodentia), with 71 species, is by far the most species rich. Of Canada's 218 mammal species, 169 are ranked only in the provinces and territories and 49 are ranked only in the ocean regions (Figure 2-10-i, Tables 2-10-i and 2-10-ii).

British Columbia (118 species, Table 2-10-i) has the highest species richness of mammals in Canada, due primarily to high numbers of insectivores (Order Insectivora) and bats (Order Chiroptera) found in the province.

The majority of Canada's 49 species of marine mammals are found in the Atlantic Ocean Region (32 species) or the Pacific Ocean Region (30 species, Table 2-10-i). Twenty-three species are found in more than one ocean region.

Species spotlight - Northern Long-eared Myotis, Myotis septentrionalis

The Northern Long-eared Myotis, Myotis septentrionalis, is a medium-sized bat found in all the provinces and territories except Nunavut. Like all Canada's bats, the Northern Long-eared Myotis is nocturnal; during the day it roosts under the peeling bark of decaying trees and at night it hunts for insects. The Northern Long-eared Myotis uses two main hunting techniques; catching insects that are resting on trees and bushes (gleaning) and catching insects in flight (hawking). In both cases, the Northern Long-eared Myotis uses echolocation to detect its prey. These bats are active only during the warmer months of the year (approximately April to September). During the rest of the year, they hibernate in caves or abandoned mines where the humidity is high and the temperature hovers just above freezing.

The nocturnal and secretive behaviour of the Northern Long-eared Myotis make this species difficult to study, but new technology is increasing the ability of scientists to investigate bat habitat use. For example, researchers can set up microphones in different habitats to record the sounds made by feeding bats. Since different species of bats make different sounds, computer programs can analyse the recordings and find out which species are feeding in which habitat type. In addition, by capturing bats and attaching tiny radiotransmitters, researchers can find out exactly which trees bats prefer to roost in. Results from these studies show that mature forest habitat, with large decaying coniferous and deciduous trees is important for these bats. This kind of information helps foresters and wildlife mangers make informed decisions about which types of habitat should be conserved to support healthy bat populations. Leaving individual mature deciduous and coniferous trees as well as patches of intact mature forest in harvested landscapes may help support Northern Long-eared Myotis populations. In turn, bats can help to control outbreaks of forest pests, such as Spruce Budworm (Choristoneura fumiferana).

The Northern Long-eared Myotis is more common in eastern and central Canada (ranked Secure or Sensitive) than in western and northern Canada (ranked May Be At Risk or Undetermined). This is due its preference for mature mixed wood forest, which is more widely available in eastern Canada, as well as the availability of suitable hibernation sites and climate. Due to its large range in Canada, Northern Long-eared Myotis has a Canada General Status Rank (Canada rank) of Secure. This has changed from Sensitive in 2000, due to a combination of new information and a process change.

Species spotlight - Northern Bottlenose Whale, Hyperoodon ampullatus

The Northern Bottlenose Whale, Hyperoodon ampullatus, is named for its dolphin-like beak and prominent 'egg-head' forehead, which is particularly large in adult males. They are found in the northern Atlantic Ocean, where they favour deep, cool water. Northern Bottlenose Whales are very sociable animals, and live in small groups, or pods. Males are larger than females and can reach up to 10 m in length, and weigh up to 7.5 tonnes! In males, the lower jaw of the beak holds two small teeth, but the female has no teeth at all. Northern Bottlenose Whales dive up to 1000 m in depth for as long as 70 minutes, searching for their favourite food of squid (genus Gonatus).

Two distinct populations of Northern Bottlenose Whales are found in Canada; one off the northern Labrador coast, within the Eastern Arctic Oceanic Region (Davis Strait population) and another off the southeast coast of Nova Scotia, within the Atlantic Oceanic Region (Scotian Shelf population). The Soctian Shelf population lives within an underwater canyon called The Gully. This population of about 130 animals has a unique migratory strategy and life history compared to other bottlenose whale populations.

Northern Bottlenose Whales were hunted for centuries for their spermaceti oil, which was used to make high quality lubricating oil and candles. Bottlenose whales were easy prey for whale hunters because they are attracted to boats by their intense curiosity. Pod-members are extremely protective of injured or distressed companions, so whalers were often able to harvest the majority of the pod, before the remaining members dived for safety. By the mid 1970's global populations of Northern Bottlenose Whales were reduced to vulnerable levels. In 1973 commercial hunting ceased and in 1977 the species was classified as a protected species by the International Whaling Committee, but global populations of Northern Bottlenose Whales have not yet fully recovered. In Canada, the Davis Strait population is currently assessed as Not At Risk by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), but the Scotian Shelf population was assessed by COSEWIC as Endangered (2002), and is now protected under Canada's Species At Risk Act.

Fortunately for researchers, the Northern Bottlenose Whale's sociable nature has made the study of its biology and behaviours relatively easy, since observers are able to approach the whales without disturbing them. The Gully, home of the Scotian Shelf population of Northern Bottlenose Whales, is a Marine Protected Area, but is surrounded by oil and gas discoveries and is close to trans-Atlantic shipping routes. Recent research in this area has attempted to determine the effects of human activities on the whales, including commercial shipping, fishing activity, and the offshore oil and gas industry. The Northern Bottlenose Whale has a Canada rank of Sensitive; this has not changed since Wild Species 2000.

Species spotlight - Common Grey Fox, Urocyon cinereoargenteus

Common Grey Foxes, Urocyon cinereoargenteus, are the only member of the dog family (family Canidae) in Canada with the ability to climb trees! This small fox has short legs and long, strong back claws that allow it to scramble up tree trunks to escape from predators or look for food, such as fruit, birds and rodents. On the ground, Common Grey Foxes also eat rabbits and other small mammals. Slightly smaller and greyer in colour that the Red Fox, Common Grey Foxes are native to Ontario and have also been recorded in Quebec, Manitoba and Alberta.

Common Grey Foxes have an intriguing history in Canada. Archaeological records from the villages of Aboriginal Peoples indicate that in the past, Common Grey Foxes were almost as abundant as Red Foxes in southern Ontario. However, the records of European settlers make no mention of this unusual species. In fact it wasn't until early in the 1890s that Common Grey Foxes were reported first in Quebec, and then in Ontario. No one is certain what caused Common Grey Foxes to disappear from Ontario for more than 300 years, or why they have become re-established over the past 100 years. However, it has been suggested that warmer temperatures in recent years have allowed northern populations, like those in southern Ontario, to survive and increase. Today, the only place in Canada where Common Grey Foxes are known to breed is Pelee Island in southern Ontario. Records of Common Grey Foxes in other parts of Ontario and in southern Manitoba are probably single individuals that have travelled across the border from the United States, where Common Grey Foxes remain widespread.

Due to its small range and small population size in Canada, and because its forested habitat is under threat from human development, Common Grey Fox has a Canada rank of At Risk. This rank has changed from Not Assessed in Wild Species 2000, due to an updated COSEWIC status assessment of Threatened.

Results of assessmentFooetnote1

The majority of mammals have Canada ranks of Secure (64%, 139 species, Figures 2-10-1 and 2-10-ii, Table 2-10-i). However, 11% have Canada ranks of Sensitive (25 species), 6% have Canada ranks of At Risk (13 species), 5% have Canada ranks of May Be At Risk (10 species), and a total of 1% have Canada ranks of Extirpated (one species, Black-footed Ferret, Mustela nigripes) and Extinct (one species, Sea Mink, Mustela macrodon). In addition, 5% of mammal species have Canada ranks of Exotic (11 species), 5% have Canada ranks of Undetermined (11 species), and 3% have Canada ranks of Accidental (seven species).

Compared to terrestrial and freshwater mammals, a lower proportion of marine mammals have Canada ranks of Secure (terrestrial and freshwater mammals: 70% vs. marine mammals: 43%, Figure 2-10-iii, Table 2-10-ii), May Be At Risk (6% vs. 0%) and Exotic (7% vs. 0%), whereas a relatively high proportion of marine mammal species have Canada ranks of At Risk (terrestrial and freshwater mammals: 5% vs. marine mammals: 10%), Sensitive (9% vs. 18%), Undetermined (2 % vs. 16%), and Accidental (1% vs. 10%).

Figure 2-10-i: Summary of the species richness and 2005 general status ranks of mammals in Canada.
bar chart (see long description below)
Long description for Figure 2-10-i

Figure 2-10-i compares general status ranks of mammal species across Canada. In Canada as a whole there was 1 extirpated, 1 extinct, 13 at risk, 10 may be at risk, 25 sensitive, 139 secure, 11 undetermined, 11 exotic, and 7 accidental mammal species for a total of 218 species. Broken down by region: In the Yukon there was 1 species at risk, 8 may be at risk, 8 sensitive, 40 secure, 6 undetermined, and 2 exotic for a total of 65 species. In the Northwest Territories there was 1 species at risk, 1 may be at risk, 6 sensitive, 42 secure, 14 undetermined, and 1 accidental for a total of 65 species. In Nunavut there were 6 sensitive, 19 secure, and 11 undetermined species for a total of 36 species. In British Columbia there was 1 extirpated, 5 at risk, 13 may be at risk, 6 sensitive, 78 secure, 1 undetermined, 1 not assessed, 12 exotic and 1 accidental species for a total of 118 species. In Alberta there was 1 extirpated, 4 at risk, 5 may be at risk, 13 sensitive, 56 secure, 6 undetermined, 8 exotic and 2 accidental species for a total of 95 species. In Saskatchewan there were 2 extirpated, 6 at risk, 2 may be at risk, 17 sensitive, 47 secure, 3 undetermined, 2 not assessed, 5 exotic and 1 accidental species for a total of 85 species. In Manitoba there were 4 extirpated, 2 at risk, 3 may be at risk, 15 sensitive, 54 secure, 2 undetermined, 4 exotic and 1 accidental species for a total of 85 species. In Ontario there were 3 at risk, 2 may be at risk, 9 sensitive, 52 secure, 4 undetermined, 1 not assessed, 7 exotic and 3 accidental species for a total of 81 species. In Quebec there was 1 extirpated, 2 at risk, 5 may be at risk, 9 sensitive, 49 secure, 1 not assessed, 6 exotic and 2 accidental species for a total of 75 species. In New Brunswick there were 3 extirpated, 1 at risk, 2 may be at risk, 4 sensitive, 36 secure, 6 undetermined, and 4 exotic species for a total of 56 species. In Nova Scotia there were 2 extirpated, 3 at risk, 7 sensitive, 33 secure, 5 undetermined, 8 exotic and 1 accidental species for a total of 59 species. In Prince Edward Island there were 5 extirpated, 1 sensitive, 21 secure, 3 undetermined, 4 exotic and 1 accidental species for a total of 35 species. In Newfoundland and Labrador there was 1 at risk, 5 sensitive, 28 secure, 3 undetermined, 5 exotic, and 3 accidental species for a total of 45 species. In the Pacific Ocean Region there were 8 at risk, 3 sensitive, 8 secure, 7 undetermined, and 4 accidental species for a total of 30 species. In the Eastern Arctic Ocean there were 4 sensitive, 4 secure and 2 undetermined species for a total of 10 species.

Table 2-10-i: Summary of the 2005 general status ranks of mammal species in Canada.
Rank CA YT NT NU BC AB SK MB ON QC NB NS PE NL PAC EAO WAO ATL
Extirpated 1 0 0 0 1 1 2 4 0 1 3 2 5 0 0 0 0 1
Extinct 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
At risk 13 1 1 0 5 4 6 2 3 2 1 3 0 1 8 0 0 0
May be at risk 10 8 1 0 13 5 2 3 2 5 2 0 0 0 0 0 0 0
Sensitive 25 8 6 6 6 13 17 15 9 9 4 7 1 5 3 4 1 5
Secure 139 40 42 19 78 56 47 54 52 49 36 33 21 28 5 4 3 14
Undetermined 11 6 14 11 1 6 3 2 4 0 6 5 3 3 7 2 1 3
Not assessed 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
Exotic 11 2 0 0 12 8 5 4 7 6 4 8 4 5 0 0 0 0
Accidental 7 0 1 0 1 2 1 1 3 1 0 1 1 3 4 0 5 5
Total 218 65 65 36 118 95 85 85 81 75 56 59 35 45 30 10 10 32

 

Figure 2-10-iii: Comparison of the 2005 Canada General Status Ranks (Canada ranks) of mammals, by habitat.
bar chart (see long description below)
Long description for Figure 2-10-iii

Figure 2-10-iii compares the status ranks of mammals in Canada by habitat. Terrestrial and freshwater mammals were found to be 1% extirpated, 5% at risk, 6% may be at risk, 9% sensitive, 70% secure, 2% undetermined, 7% exotic, and 1% accidental species. Marine mammals were found to be 2% extinct, 10% at risk, 18% sensitive, 43% secure, 16% undetermined and 10% accidental species.

 

Table 2-10-ii: Summary of the 2005 general status ranks of mammals in Canada, by habitat. a
Number Rank Terrestrial and
freshwater mammals
Marine
Mammals
0.1 Extirpated 1 0
0.2 Extinct 0 1
1 At risk 8 5
2 May be at risk 10 0
3 Sensitive 16 9
4 Secure 118 21
5 Undetermined 3 8
7 Exotic 11 0
8 Accidental 2 5
Total - 169 49

a In Wild species 2000, species assessment results were presented as the proportion of resident species ('resident species' excludes species with Canada ranks of Extirpated, Extinct and Accidental). In this report, we have used the more straightforward method of presenting results as a proportion of total species richness. Therefore, proportions given in the 'Results of assessment' sub-sections cannot be directly compared to results given in the text of Wild Species 2000. To compare results for terrestrial and freshwater mammals directly between the text of Wild Species 2000 and this report please use the following figures, which represent the 2000 results as a proportion of total species richness: Total species richness: 167 species; Extinct/Extirpated: 1%, At Risk: 3%, May Be At Risk: 5%, Sensitive: 14%, Secure: 65%, Undetermined: 4%, Not Assessed: 1%, Exotic: 7%, Accidental: 1%. For marine mammals: Total species richness: 48 species; Extinct/Extirpated: 2%, At Risk: 6%, May Be At Risk: 0%, Sensitive: 10%, Secure: 65%, Undetermined: 8%, Not Assessed: 4%, Exotic: 0%, Accidental: 4%.

Comparison with Wild Species 2000

Since Wild Species 2000, taxonomic changes have been made to four groups of species, due to new genetic analyses; Eastern Wolf (Canis lycaon) is now ranked separately from Grey Wolf (Canis lupus), Maritime Shrew (Sorex maritimensis) is now ranked separately from Long-tailed Shrew (Sorex dispar), Eastern Heather Vole (Phenacomys ungava) is now ranked separately from Western Heather Vole (Phenacomys intermedius), and North Pacific Right Whale (Eubalaena japonica) is now ranked separately from North Atlantic Right Whale (Eubalaena glacialis). In addition, Nutria (Myocastor coypus), ranked Exotic in 2000, has been removed from the national list.

Of the 210 species that were ranked in both 2000 and 2005, the majority retain the same Canada rank they were given in 2000 (81%, 170 species). However, 3% have changed to a Canada rank with a reduced level of risk (seven species), 5% have changed to a Canada rank with an increased level of risk (ten species) and 11% have been moved into or out of the Undetermined, Not Assessed or Accidental categories (23 species). The majority of these changes were due to new or updated COSEWIC assessments (40%, 16 changes, Table 2-10-iii), or changes in process1 (35%, 14 changes). In addition, 13% of changes were due to new or improved information (five changes), 8% of changes were due to a combination of new or updated information and changes in process (three changes), 3% of changes were due to a combination of biological change and new or improved information (one changes) and 3% were due to biological change in species population size, distribution, trends or threats (one species). Changes in Canada rank have not led to substantial changes in the proportion of species ranked in each category (Table 2-10-iv).

Table 2-10-iii: Species summary of Canada General Status Rank (Canada rank) changes, for individual mammal species, between Wild Species 2000 and Wild Species 2005.
2005 Canada
rank
2000 Canada
rank
English name Scientific name Reason for
changea
At Risk May be at risk Ord's Kangaroo Rat Dipodomys ordii C
At Risk Sensitive American Bison Bos bison C
At Risk Sensitive Blue Whale Balaenoptera
musculus
C
At Risk Secure Northern Fur Seal Callorhinus ursinus C
At Risk Undetermined Common Grey Fox Urocyon
cinereoargenteus
C
May be at
risk
Sensitive Great Basin Pocket
Mouse
Perognathus parvus B
May be at
risk
Sensitive Black-tailed Prairie
Dog
Cynomys ludovicianus C
May be at
risk
Undetermined Western Harvest
Mouse
Reithrodontomys
megalotis
P
Sensitive At Risk Bowhead Whale Balaena mysticetus C
Sensitive Secure Atlantic Walrus Odobenus rosmarus C
Sensitive Secure Gray Whale Eschrichtius robustus C
Sensitive Secure Narwhal Monodon monoceros C
Sensitive Secure Northern Sea Lion Eumetopias jubatus C
Sensitive Undetermined Harbour Porpoise Phocoena phocoena C
Secure Sensitive Pronghorn Antilocapra americana B/I
Secure Sensitive Cascade-mantled
Ground Squirrel
Spermophilus
saturatus
I
Secure Sensitive Eastern Red Bat Lasiurus borealis P
Secure Sensitive Northern Long-eared
Myotis
Myotis septentrionalis P
Secure Sensitive Humpback Whale Megaptera
novaeangliae
C
Secure Sensitive Southern Flying
Squirrel
Glaucomys volans C
Secure Undetermined Northern Collared
Lemming
Dicrostonyx
groenlandicus
I
Secure Undetermined Prairie Vole Microtus ochrogaster P/I
Secure Undetermined Richardson's Collared
Lemming
Dicrostonyx
richardsoni
P/I
Secure Undetermined Harbour Seal Phoca vitulina P
Secure Undetermined Thirteen-lined Ground
Squirrel
Spermophilus
tridecemlineatus
P
Secure Not Assessed Minke Whale Balaenoptera
acutorostrata
C
Undetermined May be at risk Western Red Bat Lasiurus blossevillii I
Undetermined Sensitive Ogilvie Mountain
Collared Lemming
Dicrostonyx
nunatakensis
I
Undetermined Secure Baird's Beaked
Whale
Berardius bairdii P
Undetermined Secure Barrenground Shrew Sorex ugyunak P
Undetermined Secure False Killer Whale Pseudorca crassidens P
Undetermined Secure Hubb's Beaked
Whale
Mesoplodon
carlhubbsi
P
Undetermined Secure Risso's Dolphin Grampus griseus P
Undetermined Secure Short-finned Pilot
Whale
Globicephala
macrorhynchus
P
Undetermined Secure Stejneger's Beaked
Whale
Mesoplodon
stejnegeri
P
Undetermined Not Assessed Sei Whale Balaenoptera borealis C
Exotic Not Assessed Feral Dog Canis familiaris P
Accidental Secure Pygmy Sperm Whale Kogia breviceps P
Accidental Secure Striped Dolphin Stenella coeruleoalba P
Accidental Undetermined Dwarf Sperm Whale Kogia simus P/I

a C: change due to new COSEWIC assessment. P: change due to procedural change. I: change due to improved knowledge of the species. B: change due to biological change in species' population size, distribution or threats.

Table 2-10-iv: Comparison of the Canada General Status Ranks (Canada ranks) of mammal species in Wild Species 2000 and Wild Species 2005.
Canada rank Number and
percentage of
species in each
rank in Wild
Species 2000
Number and
percentage of
species in each
rank in Wild
Species 2005
Summary
of change
Reason(s)
for change(s)
Extirpated/Extinct 2 (1%) - a - -
Extinct - a 1 (<1%) - -
Extirpated - a 1 (<1%) - -
At Risk 8 (4%) 13 (6%) Change in taxonomy b,
COSEWIC assessment c
May be at risk 9 (4%) 10 (5%) COSEWIC assessment c,
Biological change d,
Procedural change e,
Improved knowledge f
Sensitive 29 (13%) 25 (11%) Change in taxonomyb,
COSEWIC assessment c,
Biological change d,
Procedural change e,
Improved knowledge f,
Combination of new
information and biological
change g
Secure 139 (65%) 139 (64%) Change in taxonomyb,
COSEWIC assessment c,
Procedural change e,
Improved knowledge f,
Combination of new
information and biological
change g, Combination of
procedural change and new
information h
Undetermined 10 (5%) 11 (5%) COSEWIC assessment c,
Procedural change e,
Improved knowledge f,
Combination of procedural
change and new information
h
Not Assessed 3 (1%) 0 COSEWIC assessment c,
Improved knowledge f
Exotic 11 (5%) 11 (5%) Improved knowledge f
Accidental 4 (2%) 7 (3%) Procedural change e,
Combination of procedural
change and new information
h

a The single category of Extinct/extirpated in Wild Species 2000, was replaced with two separate
categories in 2005; Extinct and Extirpated. See the Background section for details.

b A change in taxonomy has resulted in a species being added to the national list.

c A formal COSEWIC assessment has been conducted, and used as evidence for a change in
rank. A biological change (i.e. a change in species population, distribution or threats) since 2000
is not suggested.

d A biological change (i.e. a change in species population, distribution or threats) has lead to a
change in rank.

e A different process has been used for assigning ranks, leading to a change in the Canada rank.

f New information has been collected or brought to light, and used as evidence for a change in
rank. A biological change (i.e. a change in species population, distribution or threats) since 2000
is not suggested.

g A combination of new information and biological change (i.e. a change in species population,
distribution or threats) has lead to a change in rank.

h A combination of new information and a change in the procedure for assigning Canada ranks
has led to a change in rank.

Key to symbols: ↑Number of species in this category has increased. ↓Number of species in this category has decreased. ↔ An equal number of species have been added and removed from this category; no net change. = No species have been added or removed from this category.

Threats to mammals in Canada

Mammals are a large and varied group, and the threats facing them are similarly varied. Habitat loss, fragmentation and degradation are important threats for many mammal species, especially large mammals, habitat specialists and mammals whose range overlaps areas of dense human habitation. Other threats to Canadian mammals include overexploitation, disease, exotic species, hybridization and climate change. In addition, lack of information on mammals such as bats and shrews make it difficult to detect or reverse population declines.

Marine mammals typically face a different set of threats to freshwater and terrestrial mammals. In particular, human activities at sea can often be harmful to marine mammals. Two of the greatest threats are entanglements with fishing gear and collisions with boats. In addition, from petroleum activity, such as seismic exploration, and commercial ship traffic may cause physical damage to marine mammal hearing or interfere with their feeding, migration or communication. Commercial ship traffic is responsible for much of the noise pollution found in the world's oceans today. Considerable work remains to be completed to explore these impacts more fully.

Exposure of marine mammals to pollutants has been much publicised. For example, the resident Killer Whales (Orcinus orca) of the Pacific coast are among the most contaminated marine mammals in the world. Marine mammals are vulnerable to pollutants for several reasons including their position at, or close to, the top of the food chain, and their long life cycles. Marine mammals generally do not metabolise pollutants well. Instead they are stored in the blubber, from where they can be passed to the young during suckling, or to predators, including humans. Marine mammals with high levels of contamination can face reduced survival and suppression of the immune system leading to increased rates of disease. However, it if difficult to make direct links between high levels of contamination and population declines.

Conclusion

Compared to terrestrial and freshwater mammals, the proportion of marine mammals ranked Secure is low, and the proportion of marine mammals with Canada ranks of At Risk, Sensitive or Undetermined is high. This reflects both the increased risks faced by marine mammals, as well how much more we need to learn about marine ecosystems and the species that live there.

This updated general status assessment of mammals allowed the general status national mammal lists to be updated with the latest scientific knowledge. Although the Canada ranks of X18% of mammal species were altered, the overall proportion of mammal species in each of the general status categories has not changed substantially since 2000.

Further information

Banfield, A. W. F. 1977. The mammals of Canada. University of Toronto Press, Toronto, Ontario. 438 pp

Cetacean Research & Rescue Unit. Bottlenose whale (Hyperoodon ampullatus). (Accessed November 3, 2005).

Fisheries and Oceans Canada. 2006. Observatoire du Saint-Laurent/St. Lawrence Observatory. Marine mammal research. (Accessed February 10, 2006).

Fisheries and Oceans Canada. 2005. Arctic marine mammal ecology and assessment research section. (Accessed February 10, 2006).

Fisheries and Oceans Canada. 2005. Cetacean research program. (Accessed February 10, 2006).

Fisheries and Oceans Canada. 2004. Aquatic species at risk - Killer Whale, Northeast Pacific transient population. (Accessed 16 January, 2006).

Fisheries and Oceans Canada. 2004. Aquatic species at risk - Northern Bottlenose Whale, Scotian Shelf population. (Accessed November 3, 2005).

Forsyth, A. 1985. Mammals of the Canadian wild. Camden House, Camden East, Ontario. 351 pp Gaskin, D. E. 1972. Whales, dolphins and seals. Heinemann educational books, Auckland. 200 pp

Hebridean Whale and Dolphin Trust. Northern Bottlenose Whale, Hyperoodon ampullatus. (Accessed November 3, 2005).

Jansa, S. 1999. Urocyon cinereoargenteus. Animal Diversity Web. (Accessed January 16, 2006).

MarineBio.org. 2005. Northern bottlenose whale - Hyperoodon ampullatus. (Accessed November 3, 2005).

Ollendorff, J. 2002. Myotis septentrionalis. Animal Diversity Web. (Accessed January 16, 2006).

Savage, A. and Savage, C. 1981. Wild mammals of western Canada. Western Producer Prairie Book, Saskatoon, Saskatchewan. 209 pp

References

Barber, K. (Ed). 1998. The Canadian Oxford Dictionary. Oxford University Press. Toronto, Oxford, New York. 1707 pp

Broders, H. G. and Forbes, G. J. 2004. Interspecific and intersexual variation in roost-site selection of northern long-eared and little brown bats in the Greater Fundy National Park ecosystem. Journal of Wildlife Management 68(3):602-610

Broders, H. G., Quinn, G. M., and Forbes, G. J. 2003 Species status, and the spatial and temporal patterns of activity of bats in southwest Nova Scotia, Canada. Northeastern Naturalist: 10(4):383-398

Burtenshaw, J. C., Oleson, E. M., Hildebrand, J. A., McDonald, M. A., Andrew, R. K., Howe, B. M. and Mercer, J. A. 2004. Acoustic and satellite remote sensing of blue whale seasonality and habitat in the Northeast Pacific. Deep-Sea Research II 51:967-986

Caceres, M. C. and Pybus, M. J. 1997. Status of the northern long-eared bat (Myotis septentrionalis) in Alberta. Alberta Environmental Protection, Wildlife Management Division, Wildlife Status Report No. 3, Edmonton, Alberta. 19 pp

COSEWIC. 2002. COSEWIC assessment and update status report on the grey fox Urocyon cinereoargenteus interior in Canada. Committee on the Status of Endangered Wildlife in Canada, Ottawa, Canada. vi + 32 pp

COSEWIC. 2002. COSEWIC assessment and update status report on the northern bottlenose whale Hyperoodon ampullatus (Scotian shelf population) in Canada. Committee on the Status of Endangered Wildlife in Canada, Ottawa, Canada. vi + 22 pp

Fuller, T. K. and Cypher, B. L. 2004. Grey Fox, Urocyon cinereoargenteus. In Sillero-Zubiri, C., Hoffmann, M. and Macdonald, D.W. (eds). 2004. Canids: Foxes, wolves, jackals and dogs. Status survey and conservation action plan. IUCN/SSC Canid Specialist Group. Gland, Switzerland and Cambridge, UK. x + 430 pp

Hebblewhite, M., White, C. A., Nietvelt, C. G., McKenzie, J. A., Hurd, T. E., Fryxell, J. M., Bayley, S. E. and Paquet, P. C. 2005. Human activity mediates a trophic cascade caused by wolves. Ecology 86(8):2135-2144

Jung, T. S., Thompson, I. D. and Titman, R. D. 2004. Roost site selection by forest-dwelling male Myotis in central Ontario, Canada. Forest Ecology and Management 202:325-335

Patriquin, K. J. and Barclay, R. M. R. 2003. Foraging by bats in cleared, thinned and unharvested boreal forest. Journal of Applied Ecology 40:646-657

Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: