As a faunal region, southeastern Canada may be said to include, a strip from the Great Lakes to the Atlantic including the southern parts of Ontario and Quebec and the Maritime Provinces. It includes those portions of the Alleghenian and Carolinian life zones which have been mapped in Canada, as well as the southern portion of the Canadian life zone. It is the region most altered by the hand of man, both in effect upon habitat and, more directly, upon the animals themselves.
Many of the animals of the northern forest are occasionally found in this transition zone. The moose is found in Nova Scotia, New Brunswick and Quebec, so also is the black bear and wolf. The large mammal which characterizes the region, however, is undoubtedly the white tailed deer (Odocoileus virginianus). It is not an inhabitant of the dense coniferous forest but rather of the cutover areas, forest borders and partially cleared areas. Deer are not so plentiful in Southern Ontario as they were during the period of early settlement when they fed on the second growth of the settlers clearings and formed an important source of meat. There are still many, however, in the swamps and wooded areas. They thrive in the "Near North" or border area of the Shield. Algonquin Park, which is a protected area, has a very high density of deer population. Nova Scotia, with an area of 20,000 square miles, has one of the greatest deer populations of the whole region. An annual kill of 30,000 is estimated to be only 20% of the total population. Here it is quite evident that deer and moose come into competition for food and the moose are losing ground in spite of their slightly higher reach for browse. In Algonquin Park a browse line is quite evident on white cedar and it is impossible to find a white cedar seedling in the southern part of the park. There are no cedars in Nova Scotia where studies in the Chignecto and Liscomb Game Sanctuaries have established that the important food plants are birches, red maple, mountain maple (Acer spicatum), poplars, withe-rod (Viburnum cassinoides), hazel, red-berried elder (Sambucus pubens), wild cherry and balsam fir.
The cottontail rabbit (Sylvilagus floridanus) was probably not indigenous but since its appearance has spread throughout Southern Ontario. The European hare or jack rabbit (Lepus europaeus) has likewise spread over the same area since its introduction in 1912. Small rodents worth mention are the muskrat, black squirrel (Sciurus carolinensis) and woodchuck (Marmota monax). The latter tends to take possession of old pastures, especially on sandy and gravelly soils, and may even invade cultivated fields where its burrows and spoil heaps are an unmitigated nuisance. Field mice and other small rodents also abound. The skunk (Mephitis mephitis), raccoon (Procyon lotor), red fox, bobcat (Lynx rufus), mink and weasel are found in various parts of the region.
Among the upland game birds are ruffed grouse (Bonasa umbellus) and bobwhite (Colinus virginianus), the prairie chicken (Tympanuchus cupido) on Manitoulin Island, and the introduced pheasant (Phasianus colchicus). The sea coast, the Great Lakes and many smaller lakes are frequented by gulls among which the herring gull (Larus argentatus) and ring-billed gull (L. delawarensis) are the most common. Among the many other birds which might be mentioned are the cardinal (Richmondena cardinalis), catbird (Dumtella carolinensis), robin (Turdus migratorius), whip-poor-will (Antrastomus vociferus), bobolink (Dolichonyx orizivorus), meadowlark (Sturnella magma), redwinged blackbird (Agilaeus phoenicius) and mourning dove (Zenaidura macrouna). Two introduced nuisances are the English sparrow (Passer domesticus) and the starling (Sturnus vulgaris).
The waters of Eastern Canada contain many species of fish, some of them valued by both anglers and commercial fishermen. The king of them all, probably, is the Atlantic salmon (Salmo salar) which formerly entered all rivers draining to the Atlantic, including the streams flowing into Lake Ontario. Its range is now greatly restricted. A landlocked form, the ouananiche is found in some Quebec lakes. All the species mentioned in the Boreal zone are found here and some others including the sturgeon (Acipenser rubicundus), the muskellunge (Esox obriensis), the small-mouthed black bass (Micropterus dolomieu) and the brook trout (Salvelinus fontinalis).