'ecological niches' is a correct and usable term in written English.
You could use it in a sentence such as: "Habitat destruction is a major threat to species that have unique ecological niches."
They occupied several ecological niches and grew to large sizes.
Their ecological niches are therefore wide open for occupation.
Monotremes are very highly modified for their particular ecological niches.
The rest tend to stay in their cages or cling to their ecological niches.
"They filter the water and provide all kinds of ecological niches for other organisms.
Spinae might have multiple functions depending on ecological niches where the spinae covered cells live.
These distinctive animals occupy a range of ecological niches worldwide virtually anywhere there is vegetation.
Soberόn, J. & Peterson, A. T. Interpretation of models of fundamental ecological niches and species'distributional areas.
Origins of bacterial diversity through horizontal genetic transfer and adaptation to new ecological niches.
Willing to spot dangers or opportunities in new ecological niches in the environment.
Peterson, A. T., Soberón, J. & Sánchez-Cordero, V. Conservatism of ecological niches in evolutionary time.
