Tundra: Plants & Animals - Natural History of Ontario (Lecture 3)
The Tundra is very windy, because it is level and flat. It has the coldest wind-chill factor
(coldest wind-chill in North America). The wind blows abrasive particles; clay and slit (the
two smallest particles) deposits range from 5-75m thick. Water collects on top of these
deposits. Tyrell Sea, the water that collected on top of these deposits. The sea is gone today
because the land rebounded (rised again). This water area now remains making a wet area
known as the Hudson Bay Lowlands. The sea stopped there because of the elevation from
the Canadian Shield (highlands). Tundra is flat, poor drainage, ponds, and fresh water.
This is good habitat for; Northern diver ducks. This includes Scaup
and Scoters (White Wing Scoter, Surf Scoter, Black Scoter). There is
also a large number of geese; including Canada Goose, and Snow
Geese (there are two forms the Blue morph and White morph).
Swans are also in the Tundra; the Tundra Swan (native species).
Why are there more geese now then in the past? – there is now crop land so this large area
of food supply is now available to make more nutrients available so more offspring can be
produced per female.
Geese have negative effects on the Tundra; (1) they eat the tubers of plants, transforming
the top layer of the Tundra, (2) their droppings contain nitrogen (adding nitrogen to the
ecosystem – changing the chemistry of the tundra zone and thus creating a
shift in the plant community).
White Snow Goose morph: the orange pattern on the face is due to digging
These birds are not there throughout the year, as when the
temperature drops it freezes the water. There are no turtles or
salamanders, but there are frogs, 2 species; the Wood Frog and the
Chorus Frog (they are freeze tolerant). They survive because there
is a lot of still water.
Half of Canada’s rivers drain into the Hudson Bay
Why are these rivers flowing North into the Hudson Bay instead of South? – the height of the
land is a divider; water blow it flows south (Atlantic Water Shed) and water above flows
north (Artic Water Shed) into the Hudson Bay (named so because this is where the water
from the rivers is flowing into).
Due to the freshwater input the Hudson Bay has 1/3 Salinity of the Ocean. Due to this the
water freezes during winter (because of the low salinity). This is another reason why the
birds leave the Tundra during winter.
Even though the salinity is low, many fish and plants are unable to tolerate the salt.
Sea ducks such as Eiders (King Eider and the Common Eider) nest along the Hudson Bay
(they feed in salt water). Loons also nest along the coast of the Hudson Bay, there are three
species (the Common Loon, Red-Throated Loon and the Pacific Loon). Loons eat salt water