In the continent that ducks live are in different parts like: Africa, North America, etc.
No.
Air, food, water.
Mallard ducks live in a variety of climates, but are mainly found in wetland/moderate climate.
The Mallard duck is the ancestral precursor to all domestic ducks except Muscovy ducks. The white ("Long Island duckling"), type of farm pond duck descended from and can still interbreed with mallard ducks. Although the domestic ducks are usually significantly larger, feral ducks often revert to mallard characteristics after a few generations. The mallard is the essential "type O" duck that dominates the duck gene pool. They're native only to the Americas but because of introduction they have been established on every continent except Antarctica. Mexican Ducks and Hawaiian Ducks are also mallard hybrids, and ornithological scientists now generally agree that all Black Ducks in existence are now carrying mallard DNA. They hang out with the white ducks, and vice versa, because they're "cousins" and share the same habits and characteristics in feeding, breeding, and nesting.
If the result you want is a mallard, yes. If mallards can just breed with other ducks, yes, a mallard duck can breed other breed ducks.
Mallard ducks are not capable of changing gender. There is no known species of duck that is capable of that.
Mallard ducks were never introduced. Mallards were the first duck ever on planet Earth.
in every type of wet lands exept for bogs
from an egg
Yes.
yes they do
Foxes, and raccoons eat young mallard ducks. Snapping turtles will also eat them. Mallard duck eggs are eaten by snakes, and crows.