Any place where their food (mostly fish) is abundant and there is a place with few predators to hunt while they reproduce. The biggest predators of most penguins are like killer whales - in the water. With that in mind, on top of the fact that penguins have evolved to stay warm in cold climates, penguins have a comfortable niche in the arctic and antarctic.
Carnivore
A niche is the role that an organism plays in it's environment, so when finding the niche of the African penguin you have to consider, where it sits in the food web, it eats and limits the population of small fish such as pilchards, anchovies, horse mackerel, and sardines. It is a food source for sharks and fur seals, so without the penguin, these animals would become on the decline too. Therefore the African penguin Niche is to balance out the Marine Habitat.
The niche, or ecological role of the Emperor penguin is that they eat fish.
the emperor penguin doesnt have a set niche it normally lives in the sea in cold climates, but when its time to mate they move to the matting grounds and mate, after the baby penguins are born the penguins move back to the sea again but befor the penguin is hatched the father sits on the egg when the mother penguin is out getting food.
It eats krill and provides food for leapord seals and killer whales. (those are its predators)
A penguin is an aquatic hunter usually in Antarctic waters. This is a broad description of the niche of a 'generic' penguin. You can add details as you wish. You could define which species of penguin whose niche you are describing, the types of fish they hunt, that they are amphibious, that they are prey for leopard seals, etc.
niche
is a niche
A niche is an organism's way of life within an ecosystem. This differs from a habitat, which is only the place where an organism lives.
The niche is blank.
A niche is a job
In most uses, "niche" is a noun. Nouns refer to a person, place, or thing. A niche is a thing. However, there are occasions when "niche" gets used as an adjective. In the phrase "niche marketing," "niche" modifies :marketing," so it's an adjective in that usage.